DEVELOPMENTAL HISTORY OF THE HOWELL ANTICLINE Thesis for the Degree of M. S. MICHIGAN STATE UNIVERSITY RANDY MAX PARIS 1977 ,. w \1 3 R cu A“ n )\ 3., I «E I m L .n... .D "II +t I S .r; C .w n U 7&0 km p.» MW 3 \ . , -~ 7. {3}-) IN '7’: p I (,UU " ABSTRACT DEVEIDPMEN‘I‘AL HIS'IDRY OF THE m1. ANTICIME By Randy Max Paris The Howell Anticline is the nost prominent of Michigan's many northeast-southeast trending anticlines. located along a major zone of basement weakness the Howell Anticline has responded to the regional tectonic forces which have affected the Michigan Basin. During late Salina tine the northeast block of this fault zone subsided as tension and gravity acted as the dominant regional forces. later as compression- al forces began to be felt throughout the region accanpanying the Appalachian Orogeny the Howell Fault zone reacted with uplift along the northeastern block resulting in a pattern of en echelon, faulted, asymmtrical anticlines that reflect sinple shear wrench fault mechanics. Hydrocarbons accumulation occurred within fractured carbonates in linear trends associated with the fault zone. Projecting this nodel into the central Michigan Basin area opens up the possibility of deeper produc- tion beneath the many northwest trending anticlines which have been the heyday of Michigan oil and gas production. DEVELOPMENTAL HISTORY OF THE HOWELL.ANTICLINE Randy Max Paris .A THESIS Suhnitted to Michigan State University in partial fulfillment of the requirenents for the degree of .MASTER.OF SCIENCE Department of Geology 1977 The author wishes to thank Dr. C. E. Prouty, Chairman of the (hidance Oarmittee, for his advice and help during preparation of this study. 'Ihanks is also extended to Dr. J. H. Fisher and Dr. J. Trow for their advice and review of the thais. Anoteof gratituie isexterdedtotlnseofdeoilarflgas industry of Michigan who provided information and materials that were used in the preparation of the thesis: the Michigan Geological Survey, Hunt Energy Corporation, and nest especially my father and Panhandle Eastern Pipeline Oarpany. Special gratitude is given to my wife Nancy, whose love and patience trade this effort worthwhile. ii 'IRBIEOFCGVTE‘N'I‘S Page E a 3 11 13 15 a e- ISGAGIS................... 30 Regional 30 HowellArea............... 32 W CI" DEVEIDPWI‘AL HIS'IOM. . . . . . . . . . . 49 OIL AND GAS PKDLL'I'ICN . . . . . . . . . . . . . . 56 WICNS. . . . . . . . . . . . . . . . . . 62 BIBLICERAPHY . . . . . . . . . . . . . . . . . 64 mm. C O O O I O O O O O O O O O O O O C 70 iii Figure 15. 16. 17. 18. LIST OF FIGJRE‘S Location of Study Area Within Michigan . . . . . LocationMap............... Major Structural Trends in the Michigan Basin . . . . Aeranagnetic Map of the Southern Peninsula of Michigan . Bouguer Gravity Ananaly Map of the Southern Peninsula of Michigan Stratigraphic Chart . . . . . . . . . . Structure Cross Section Across Howell Field. . . . . Structure Cross Section Across Fowlerville Field . . . Structure Cross Section Along Strike of the Howell Fault WW I O I O O I O O O O O O O O O O 0 Regional Tectonic Setting of the Michigan Basin . . . Niagara Structure Map . . . . . . . . . . . . Dundee Structure Map . . . . . . . . . . . . UpperCincinnatian-UnitS-ISOpach. . . . . . mstored Stratigraphic Cross Section Across Howell Field, mm“ wira G O C O O O O O O O O O O O O DundeetoSalinaGIsopach.......... Restored Stratigraphic Cross Section Across Haven Field, DatumBellShale.............. BellShaleIsopach............. iv 12 16 17 18 22 24 25 34 36 37 4O 41 42 45 Figure 19. 20. 21. 22. Berea-BedfordIsopach........... Structural Features Resulting Frcm Simple Shear Wrench Progression of Axial Plane Rotation During Sinple Shear Defornetion............... Possible Migration Path of Hydrocarbons Along Fault Plane Page 48 51 53 60 INI'KDDUCI‘ICN Lying nearly along the northwest diagonal of Livingston County in southeastern Michigan, the Howell Anticline is one of Michigan's Host prominent linear features (Figs. 1, la). It is a part of a system of anticlines beginning with the Northville Anticline in Wayne and Washtenaw Counties which strike northwest through Livingston County, which Newcatbe (1933) designated the I-bwell-Omsso Anticline. Addi- tional drilling will nest likely extend this feature thrmgh Shiawasse County and into Gratiot County, but current well control limits this extensiontoanuchbroaderregionaltypeof stuiyratherthanalocal study such as this. The anticlines along this trend are nortlmterly plunging and are roughly sub-parallel structures which Ells (1969) has termed the Washtenaw Anticlinoriun. Covered by a blanket of glacial till ranging between 40 and 350 feet in thickness, the Howell Anticline is not discernable fron a surface study. 'Ihe discovery of the anticline may have been in the 1920's whenitwas recognized thattheSaginaw fometionwasmtcontimms across the area (in Kilbourne, 1947). Newconbe (1933) in an extensive stuiy of Michigan geology defined the Howell-Owosso Anticline with a structure map on the Berea Sandstone. He suggested and presented evidence of an en echelon series of faults along the southwest flank of the structure with a total vertical displacement, throw, of as nuch as 1000 feet on the Berea Sandstone. Keck (1938) did sane early LII! 37. £1.10. CAI... it‘ll (Ill Figure 1. location of Study Area Within Michigan 30-0 8&4 89-! 8'04 an. out I2E RSI R45 R55 Figure la. location lap Location of fields and cross-section lines RTE 4 geophysical work in the area by conducting a resistivity survey. His results slowed the Saginaw was offlapped along the sides of the struc- ture, with Goldwater shale exposed higher up on the anticline. Kil- bourne, (1947) , with more well control than was available to Newocnbe, drew a structure nap on the Dundee formation again shoving faulting along the sthhwest flank. Cohee and landes (1958) noted that the crest of the Dundee structure did not directly overlie the crest of the Niagara structure of the Howell Anticline. Hinze and Merritt (1969) noted that the Howell feature was on top of a Mid-Michigan gravity and negnetic high. Checkley (1968) conducted a field study of the North- ville Field connected the Northville anticline with the Howell Anticline as being a part of the same structure. Ells (1969) used the control provided by the sixty-nine wells of the Howell Storage Field to yield good definition of the structure dovn to the Niagara formation in the region of Howell. Since Ells' work, there has been additional drilling near Fovlerville in Livingston County. The purpose of this study is to cmduct a broader study of the Howell Anticline, exterriing the structure mrthward to include the Fowlerville Field arrl to the southeast to catch the northern terminus of the Northville Field. It is hoped that this stuily will illustrate the developmental history of the Howell Anticline fron the late Ordovician (Cincinnatian) to Recent. It is further the purpose to construct a possible nodel, based on the Howell Anticline, to explain the many mrthwest-soatheast striking anticlines of the central Michigan Basin area (Fig. 2) . \ b \ ,. ' "'""‘_/ muuuonul - Cold-«ow .uu . . Duo-u. M"- -0. home. _.... w — 10500:. loo.:no h 'Mh' 11“. a - IKIII MIC. -— - Figure 2. A\OIII .- 5 'i‘\ 1‘ ovuu [fun-nun ou' l uuu u ..\ \o ‘ I . E ‘ C ' . ‘ \guvm : “‘0” \ ‘ [Lt-OI... n W Major Structural Trends in the Michigan Basin (colpiled by Prouty, 1971) 6 Previous Work 'Ihe Howell Anticline is the most prominent of this trend of northwest-southeast striking anticlines in the central Michigan Basin area. Pirtle (1932) attributed this fold pattern to trends of struc- tural weakness in the Precambrian basement rocks. He further stated that the folds were due to vertical forces during the early history of the basin with continued deformation following horizontal conpression during middle Mississippian time. Deep seated basement faults were believed by Newwconbe (1933) to control the localization of the many en echelon folds of the Michigan Basin. He felt that these structures were the effect of shearing due to noverents along deeply buried faults in the basement complex. 'I'nese faults were along lines of basarent weakness developed during Keween- awan time, according to Newconbe. The principal folding of the anti- clinal trends occurred during the late Devonian with subsequent trove- ment during later periods accentuating the structures. The force that formed the anticlines is attributed to "growing stresses forcasting the Appalachian Revolution" (Newcorbe, 1933) . Kirkham (1937) believed the Michigan Basin was the result of a shifting of large magma bodies fron one area of the earth's crust to another. During this novatent the Precambrian surface becane marked by joint systems, faults, rifts, and shear zones creating zones of weakness along which vertical forces could later act. Step faults along these lines within the Michigan Basin resulted in the subparallel anticlinal trerris. The doninant positive structures are the cores of old Precambrian nomtains according to lockett (1947). The principal movenent was 7 subsidence of the basin. The weight of the sediments from these noun- tains provided the mechanism of subsidence. During the Paleozoic, three sides remained stable as the area of the Ontario Sag continued to subside resulting in a system of fractures in the basement. Conti- mied sediuentation caused differential subsidence with preference on the basinward side of these lines of weakness. lockett attributed the mid-basin anticlinal trends to this subsidence. Kilbourne (1947) concluded that the area of the Howell Anticline was a local low until Goldwater time. At the beginning of Goldwater time nomal faulting along old lines of weakness in the basement rocks resulted in uplift of the northeast side of the fault and the corung into existance of the Howell Anticline. Cohee and landes (1958) believed that the Michigan Basin underwent its greatest episode of subsidence during the late Silurian, with downwerping during Salina, Bass Islands, and Detroit River times. They further stated that the najor structural deformation of the Basin occurred during late Mississippian and pre-Pennsylvania times. This episode of deformation formed the structural traps in Michigan. Hinze and mrritt (1969) noted that the vertical magnetic intensity nap (Fig. 3) and the Bouguer gravity anonaly (Fig. 4) map closely parallels the northwesterly trend of the mid-basin anticlines soith of 40°30'N lattitude. Of particular interest is that the Howell Anticline is very closely associated with the Mid-Michigan gravity and magnetic High. 'Ihey attributed this close allignnent of trends of intrabasin structures and geophysical anomalies to lines of weakness in the basanent omplex that are associated with a rift zone filled with basalts delineated by the Mid-Michigan gravity and magnetic anonalies. '- u an! , or. . o . - 0 ”out“ .1 Donn-0d d W . lieu“. sm- Idnnlt' . I”. "m M"; an..." “OI“! I” PM 0' man My um. W 0! land m Sutton hot-uh » (6‘ .' ~ ~_. 00" Ilolluo . Cutout Damn! I. I..." Figure3. AermagneticMapoftheSoithernPeninsulaofMidiigan ' Y 5 , noun mun noun on - 5 3 . . mum nun-u . . . . ' - - - ' ’ ' ' o0 m' w, 'omn-ou ow cannon-U. u Ioloonfly. on»... W by Ooologlool “no, mun». Io to! lotonl ( Cootoot lotouoI ‘ “ll. Mlmuflwuomuotlt In“)... I" o! 3..." o! Ioooofluuoo I. “dun“ 0! Ilwloloo. Ito 3mm ooonouou ulov to tho Uotoofloool 0mm “III“ «I o toot “out, o! 2.01am- ' I O I I N ”I... f ........... ”'1‘. ,_ n ' x INDIANA a' Figure 4. Bouguer Gravity Anomly Map (frtm Hinze, 1963) 10 The structures are then due to rejuvination of these basement features during later episodes of the Basin history. Hinze's gravity and magnetic maps also reflect the slight change fron doninately northwest- southeast to north-south in the northern area of Southern Michigan that Newconbe (1933) had noted earlier in the shallower Paleozoic rocks. Hinze and Merritt (1969) attributed the formation of the Michigan Basin to isostatic sinking as the crust readjusted to added mass of basic material in the basement corplex. Their work is based on regional gravity and magnetic surveys of the lower penninsula of Michigan. They further associated the Michigan Basin with the lake azperior Basin, the Michigan gravity and magnetic high being related to the Mid-Contirent Gravity High along which the lake Superior Graben fouled. Ells (1969) in a study of the Howell Anticline discounted the presence of a fault along the west side of the structure. Ells described the Howell Structure as a "series of linear, sorewhat off-set anticlines". He attributed folding of the structure to minor faulting of deeper horizons, beneath the Trenton-Black River, along the west flank with possible accentuaticn of the structure on the Dundee forma- tion by solution and renoval of the thick Saline salts fron the flank of the structure. Ells then described the Washtenaw Anticlinorium, of which the Howell Anticline is a part, as a structure controlled by raster fault blocks in the basement rocks. Mast of the novement occurred during late Mississippian (Meramecian) time though minor novement could have begun as early as late Ordovician. He further mted the similarity between the central basin Dundee structures and the Howell Anticline as being along the same doninant structural trend 11 and probably controlled by basement rocks. Fisher (1969) associated the Howell Anticline with faulting. According to Fisher the major period of basin subsidence occurred during Salina time. The major episode of folding in the central basin area is late Mississippian. Methods and Procedures 'Ihree structural cross-sections were constructed fron gamma-ray neutron logs. There are two dip cross-sections and one strike cross- section. The cross-sections serve the dual purpose of introducing the log characteristics upon which the formation tops were picked and to present a quick visual picture of the Howell Anticline. 'Iwwo restored stratigraphic cross-sections were also constructed , again to present a quick visual presentation of the paleo-structure at the tine the upper- nost units were deposited. 'Ihe interpretive study incorporated fornetion tops based on necha- nical log picks. Where these nechanical 1093 were unavailable, State printed sanple logs were used for taps . For-nation tops used were Trenton, Utica, Cicinnatian, Rachester, Brown Niagara, Salina G, Dundee, Bell, Traverse Formation, Antrim, Berea, Sunbury, and Coldwwater, as nailed on the Michigan Stratigraphic Chart (Fig. 5) . The tops were based on lithologic characteristics of the gamma-ray and resistivity curves on the nechanical logs. Well cuttings were eJ-camined in several selected wells to check for concurrence of my sample interpretations and the interpretations of the State geologists. 'Iwo structure maps and six isopach maps were constructed fron these data. Figure 5. Michigan Stratigraphic Chart ~00h&O‘- “Ia-o-D‘h—oow wddumdu—dafi Ir...- ~d‘.-d~u_o~ mm ”an“ “'1 Butt-0 huh_ _.— in”. .:.- ~-——- -— ——-— --.———- Q... -o b.‘ Wk I—A‘ .lhh (“I ._....__. -d in (an..- h.’. H. ~-*-..- but hd~~--Oh loo-huh —. .00- ~—‘ ‘—~ H“.—— —--—&0& fl... 0-.— _onoo- hhh n:— “B .I. *Iofl" outfit-ion _--- —-oo- ~d|fiu .- O-QIW .__-_ . _.--m—- bun-nib! _ (A... I“.- n- I In. o|t~u_—I'h-—_- _-Ih w-‘ in... *9... .__'—~— .’ "..- I..- “Q Hd*h_ —-p loo-Go. ......o~ ~hh’v goo—r... -. _._.-oo-- '-_,-Oh '--_ . -_”_O —_—h-. -hd‘h~OQ-—v~~hbd ~¢~l~mfi_~—-O- -o_~~-~h~—u-l -b—h ~‘CO— STRATIGRAPHY General Section Group and formation names used in this study are based on the stratigraphic chart (Fig . 5) . Formation contacts were based on work done by the Michigan Basin Geological Society (Fisher, et a1, 1969) . 'Ihese publications were used to maintain consistancy with generally accepted nomenclature and formational boundaries. Previous work done by others as regional studies on the variois units were also incor- porated to observe changes in lithology, whether it would be a regional gradation or a local lithologic change in the proximity of the Hoell Anticline. Newwhart (1976) described the Trenton as a brown fossiliferous limestone wwhich grades into a dolomite in Western Michigan. The Trenton, inmanyplaces, iscappedbyathindolonite. lnthe easternpartofthe Michigan Basin the Trenton limestone is dolomitized along linear trends associated with faults. Nurmi (1972) described the Utica and the upper Cincinnatian shale unit, his Unit 5. Nurmu's Unit 6, the upper most Cincinnatian is absent in southeastern Michigan. The Utica is a dark colored shale, generally darkest near the base grading lighter towards the tip of the unit. Unit 5 consists of interbedded carbonates, which are argillaceois limestones near the central Basin area grading to dolomites near the Basin margins; and greenish grey shales near the center of the Basin 13 14 which grade to green and red shales near the Basin margins. Potter (1975) described the Clinton Group. The lower part is the Clinton restricted, a tan to gray dolomite which becomes split to the southwest by a thin grey dolomitic shale streak. The Clinton is over- lain by the Rochester Shale, a thin grey dolonitic shale. In southern Michigan the Rochester is a good marker bed at the base of the Niagara. Mesollela, et al, (1974) have described the Niagara and Salina Units. The Niagara is a light colored dolomite at the base. Throughout the Basin it is overlain by a thin brown dolomite often referred to as the Brown Niagaran. The Salina A-l Evaporite is a salt near the center of the Basin which grades into an anhydrite near the Basin margins. The A—l Carbmate is a dark brown, very carbonaceous, highly laminated carbonate. The algal laminations of this carbonate have led to it being termed a "poker-chip shale". The A—Z Evaporite is also an anhydrite near the Basin margins and a salt at the Basin center. The salt also grades upward to an anhydrite, which in turn grades into the overlying A-2 Carbonate. The A-2 Carbonate is a brown to grey carbonate which, inplaces ishighly laminatedbyalgalmounds. TheCandGunits are described by Fisher, et a1, (1969) . The C-shale is a green-grey shale, somewhat calcareous. The G-Unit is a thin, dark grey, generally anhydritic , dolomitic shale . The Lucas, upper Detroit River, is an interbedded evaporite and dolomite sequence (Majedi, 1969) , the dolomites being brown to tan and the evaporites being salt confined to the central Basin grading to anhydrites near the Basin Margins. According to Bloomer (1969) the Dundee is a buff to brown to grey finely crystalline limestone, the central Basin, western, and .IPEIIIII‘IIIIIII 15 soitmestern areas are a dolomite. He notes a breccia zone in the upper part of the Dundee. The Dundee is overlain by the dark grey to black calcareous Bell shale. The Bell is less argillaceous and more cal- careous at the base. Asseez (1967) described the lower Mississippian section. The Antrim is a black, pyritic, radioactive shale, though Asseez does note some color variations within the Antrim. The Bedford is a blue- grey shale, with sand and silt stringers. The Berea is an interbedded sandstone, shale sequence; both are grey in color. Overlying this is the black carbonaceous Sunbury Shale. Howell Section General descriptions of only those portions of the stratigraphic coltmn covered by this study are given below. The rationale for differentiating the units is given along with the descriptions. Refer to the structure cross-sections (Figs. 6, 7, or 8) for log character- istics of the various units. The Brazos-Kizer well in section 14 TZN R4E was used as the standard section. Descriptions are as follows: Trenton: limestone, brown; finely crystalline to dense, grades to thin brown dolomite near top; sharp break away from shale marker on logs Utica: grey-greenish grey, limey shale, occasionally becoming shaley limestone; top of Utica is fairly difficult to pick, as it grades into a calcareous shale above; the pick is made on this change to a more calcareois shale as the gamma-ray and neutron curve begin to move out from the shale line Upper Cincinnatian: red and green silty shale; the upper Cincinna- tian was picked as the first shale below the Manitoulin Dolomite; it is not a clean shale, getting many limestone stringers mixed in with it; this unit was relatively lighter colored ranging from red to green soft, silty shale; around A PATRTCK KLEWSCHMIDT I 28752 NW NW NW l7-2N—SE _W N __-.,_~_.______A-_- __ J‘JCTTQ‘L MARSHALL BRAZOS KIZE 25 SW SW NE M- 2N-4E L «g; A, R 868 0/ ._. «L/ PEPL ! WILSON-BUSH ETSELL T l6067 26758 SE NW NE NE !2-2N-4E 5-2N—5E PEPL L T ‘r ”1”,»va ‘ / 7/, Al MOBIL HESSHORE 27986 NE NW NE H-BN-SE A Y / / / e? L / Figure 6. 3 / ( LN» L Structure Cross Section Across Howell Field TY W ‘‘‘‘‘ ~ ~ _, \ as R“ a. - “__i U ‘ _ _ —“w _“K7_ 3‘ \\\ ‘QEDF _ V ¥ 7— r VAv—H— r ‘ A < \\ OR \\ \ « (2:. A V\\\\ MELJTL \ F ' at] \\l\ ”Wu: J ‘21 \\\ cowwnep I {I _\‘\\ \ ? \\‘ \’ a 4‘?" \ 1} L L d //<: ’ :4 ‘3! [RAVERSE 757/ Q /" .3 g; V, L(;,_ , fixfin 1 A LIYN. V i usage i LL '/"/ (f \\\ \‘ [7/ . \V \\ \ %/ \) r. 1/ i/ BELL ‘\\ . I y > L» ’ ‘ 'N L L AM" I ; . , DUNDEE I / ‘ _ .::~ "_'_"__“M_‘~_-‘m A- k - < L / \ \ _ _ _ , “ i; T_::_ 5’2; ‘—"’ ' ' " ‘W" ‘Tnmwzsv‘““fi{’:;g' «HERB ,. H’L/ " 2 A 2 ” BEREA-BEOFORD ‘1' I g 2 ‘242 E V W _ ‘ ~§ “ -E~‘~xrh i l, LUCAs g ’E _‘_~ ~ _ _~\—', A b ' I ' 7/ § 1 . 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HUSKEGON DEVELOPMENT 09 0. “5325733: j “cw“ scare u 06 3 NE NW re COOL oi oi I 28499 ' M 28739 SW ”-3”- SWNW :2 55-4N-3E T5-3N- g ( ~ ‘\ - " 7 .- ‘ -. , ~_,-. ' ‘ ‘\.., ‘ ‘Nj/22 \fl“\‘ N 7‘ /’L , COL Duran . _ j; ANTRTM K\ T \ \ \ 2 . ___y I r, 7_ H , V K TPAVEPSE‘ 7 .1 W W \E T L A \ L E \ \L \L \ \L \ _/ L A Mull--- L T T -rMW-W~-J\/rr {T “ ='! L ,L L U f .i L L L I: ‘5 L L L l L L L Le...» peru- m .rvrlux/ _________.l___ / / ,/ / L l / L / LIL L A L V.M J L DUNDEE - 2 22 2 _“‘~ .. 4 2‘2:- LUCAS I :3: 30‘ N H IT II 1 My . e! H ‘1 Vi‘ i h. 'V IhY ’1 in n T d ‘1 Wu I' uw—~——._ < 4 a _‘ ‘ \\‘_\\\ “\\-‘\ \K. M L 4.? l 2 - . E VADO 272" ~ - , Q'T ‘— , F 7‘ ~.__ -._. 4F \\‘\ fie; ,_‘\<“ ~ \ .C‘RBONF\ \,l\ ~ «5: ,\ _\__ “—e \_ \WW / 0—. n: ”/4 , 1‘ ;.\ CS!B%/,WW H: mAOAFE A _. x "’1 '22, 7/ podL.) I / f / Figure 7. Structure Cross Section Across Fowlerville Field OEVL “'pr . - WSKEOON neurons!” 0' 0' _ u u r roman!!!" "too- Dtvum N o! "W9?! xuuuuw .1 oi "no” 0.6206: 25:07 KLEIN I sgnn}‘ zew9‘ 3: no u: 5* SE 2900! y " so NE NE - 7-2N-56 I! so 3: “E “E 20 in as '2'2~22C 22-¢~.3: P 3* 35 coo-"II , A ‘1”\7».-_7\ . 77 / 'I \ \ RF ‘N / \ L I I I I I I I I M N“ I L; J / / / \ \ \ \ \ v N / I I I I I l 1 I i 8ka fl AV ”Iii“. _, 1Q‘V \\ \ f \I \ | ‘I. I ‘- I. I (M4 222‘ __ I ‘.q{ .‘-4 “/7 g V (’_/‘4 A ‘1‘ _ h n < ‘ _ »______—_————4e+L-_—!_.—l '[..—‘.L' V .__-.—. .....r ‘ 1 . . _ . . . _ H I ’//‘ // /' 7 \ j / ant - ‘ V _.- ‘ I / .2. I .7 I I I I I l ‘ I I ‘ I II I I ""1 I \ \ \ \ I \ I I I I I I 03 — I W“ 222 ouunn _, _ NC” I I #f I A T / 2 \ \ \ \ I fi 8 E \ \ \ \ \ \ 2W'MM VWWW ' I Y “‘“HWWM f‘“’-I- I ’T‘ | I I I I I I / / 222’ 222“ , snvnwu 2 \ . 7 30-: anc I I I I I I I I * r-A/ “‘4’ H“—- ' \— L, \ \ I _ L La ‘ I [p >-\\\\ \ 1‘ / // 2‘ *1 ‘\ 0‘35 ISLA~09 ‘ ,/’ 4/ ’ ’/, /" / 2;\ ‘ ,/ I / 2 ,/ § > \I‘ /’ r. 2\ 22;- i :T2 2% fi ‘ -—_ i y _ } ‘L // F K —\ _ ‘ q i ~——. ‘ _‘_ _ I \\\ f- \ \ “A 2"f~ravrek\"’¥q4‘&w I I I I 4 2\‘2 I“ \ \ \ \ . ’"W W I I q (“W‘vmr‘rop fume...“ /, / / , / I A Y . ‘\ \ \ "LANE” .V ‘1‘ ,. l 4 Y m-«a h. .» r , I I I I I I I I I I I \\ ‘WiNW/n . p “"00“” on! " 2 * ' ~-_ 7» l-f (“'0 . 7 _,.4‘4' ,}\- L*\‘\\ ‘-\_ 2 ' 2 / "‘6" l \ l Alt 4/, \? L~>i\ ‘ e \2 , g—I (And‘ 2' 22‘ 2‘ 222\\“ 222 \\\ \ r-\ > r A g > \ ‘\ ' ' /__H , , 2 \ \ c . / g2 ' .; :\\ t -' r" 7/ " “"” //"'/ \JR ‘ a e. ._ \ _.—/,2 2/ ‘\ I / .i 4 ’7 2/ “ \\ I Figure 8. Structure Cross Section Along Strike of the Howell Fault System l9 Livingston County the base of this unit was picked as the return to the underlying carbonate; log picks are based on the increased gamma-ray response lying between the low gamma-ray curve of carbonates Rochester: this unit was used primarily as the base of the Niagara; it is a very thin green to grey shale; it has a good shale break on the log both from the underlying Clinton Dolomite and the overlying Niagara; marked by an increased gamma-ray response Niagara: white, light grey to blue-grey dolomite; finely crystal— line with infrequent streaks of pink dolcmite; in some wells it is very slightly shaley; it grades upward into the Brown Niagara (Guelph) which is brown and finely crystalline (the Brown Niagara is the reef facies of the Niagara); off the Howell structure it is generally dense and tight, over the structure the porosity is intercry- stalline (a fresh break will absorb water almost like a sandstone) to vuggy-sane being fairly large (1/2"), but more camonly pinhole porosity; the Niagara has good log definition being in contact with the overlying anhydrite; in the area of Ingham County this definition is lost where the A-l Anhydrite is absent due to pinacle reef build up; in this situation the A-l Carbonate and upper Brwn Niagara were grouped together as undifferentiated Carbonate A-l Anhydrite: anhydrite, white to grey; absent over reef buildups, also pinches out southward as it does not cover the massive reef in Washtenaw County; sharp peak of low response on curves A-l Carbonate: brown dolanite, very carbonaceous; algal laminations give the unit a "poker-chip" characteristic which has led it to be described as "shaley"; porosity is again limited to the region of the fault zone and it also is character- istic as the sample appears finely crystalline when dry but disintegrates to a very sandy texture when acid is applied; log definition is a sharp increase in curve response from the overlying evaporite A-2 Evaporite: good clean salt at base with many thin dolomite stringers; grades upward into an anhydrite; the whole unit becomes anhydrite as it thins southward, lapping onto the massive reef; log character is very distinguishable as a drop on neutron curves A-2 Carbonate: brown, carbonaceous, finely crystalline dolomite; care must be taken to avoid a limestone stringer in the overlying B-unit, otherwise log definition is good Salina "C-Unit": grey, dolomitic shale; good shale break on log curves, thin limestone streak near the center of the unit 20 Salina "Gr-Unit": thin grey to dark grey shale to shaley dolomite unit; in samples it is picked as the change from brown shale or dolanite in the overlying Bass Islands to grey in the Salina G; on the gamma-ray log it is more easily distinguished as a good shale break on the gamma-ray curve frcm tie overlying Bass Island Detroit River: picked as the first upward oocurance of anhydrite in a light brown limestone; very easy pick of FDC logs as the curve kicks out demarking a very dense unit; neutron peaks follow a similar pattern as do resistivity peaks Durriee: light brown to brown limestone, crystalline; the log characteristic is almost as good as the Utica-Trenton contact being a very sharp break away frcm tle shale marker of the overlying Bell shale; low uniform gamma-ray curve, with associated high neutron readings Bell: grey calcareous shale, develops a very limey streak in it which thickenswestwardtomrd InghamCounty; towardthe east the contact with the overlying Traverse is sharp on the log upon return to a carbonate; as the calcareous streak thickens care must be taken to maintain a consistant pick Traverse: the Traverse Group is an alternating grey to brown limestone and grey to brown shale unit with much gradation between tie two extremes; quite fossiliferous; tre last strong radioactive kick of the overlying Antrim is used astletopcftheTraverseonthe logs Antrim: black shale, pyritic; very high gamma-ray response on logs Bedford: grey shale, satewhat silty; much lower gamma-ray response than Antrim Berea: grey sandstone, contains shale stringers; contact with overlying Sunbury is very sharp on the 1093 Sunbury: thin dark brown-black shale; very high radioactive peak on the gamma-ray log STRUCTURE Regional Framework The Michigan Basin is a gravity sag basin of the Central Interior region on the North American Continent (Fig. 9). To the northwest, mrth, ard northeast tie Michigan Basin is bounded by the North American Shield consisting of an exposed Precambrian igneous and metamorphic calplex. A ring of arcles, the Algonquin Arch to tie east, the Findlay and Kankakee limbs of the Cincinnati Arch to the southeast and southwest respectively, ani the Wisconsin Arch to the west... carplete tte relative- ly low relief border of the Basin. The Grantham Sag and Logansport Sag provided inlets to the Basin during different epochs of the Basin's history. Within the Michigan Basin there is a strong trend of rortl'lwest- southeast trending anticlines (Fig. 2). The most praminant of trese is the Howell Anticline. The Northville Anticlire is part of tie same system as the Howell Anticline. Ells (1969) has termed this system the Washtenaw Anticlinorium. 'I'ne anas-anroe Anticline, a large faulted structure, terminates in Livingston County, strikes northwesterly through Washtenaw County, turns, and strikes south through Bbmoe County to join the Bowling Green fault system of Ohio. The Albion-Scipio Oil Field is a third northwesterly striking fault system in southern Michigan (Ells 1962, Merritt 1968). The Howell Anticline has been mapped in several regional studies. Syrjamaki (1977) showed shear faults along the Howell Anticline and a 21 22 pt». . MICHIGAN BASIN \\\\ mama-man. “x w m a 7m u; u _.+.... mama-du- —+—qu~h‘ ‘ 1111-"? 'd.h~uumm ..../ Duh m .7». Inlay.“ W." l/ hum“? “a,” In.“ In”, mum-cu. “Him “Manama-Q 01-h. In w w [Outhouliu Figure 9. Regional 'Iectonic Setting of the Michigan Basin (from Ells, 1969) 23 subparallel structure to the southwest in his Prairie Du Chein study. Seyler (1975) on his regional Trenton structure depicted the Howell Anticline as faulted along the southwest flank by a single continuous fault zone beginning in TSN RZE and dying out in the south of TZN RSE. He did not fault the area of Green Oak or Northville Fields. The fault was named by Fisher (personal communication, 1977) on his Niagara structure, while 13115 (1969) believed tie structure was not a faulted feature but rather an asymmetrical anticline with a steeply dipping southwest flank. Majedi (1969) concurred with a fault zone along the soithwest flank on his Detroit River structure map. Bloomer (1969) chose not to draw the anticline as a faulted feature thoigh he recog- nized that the Howell Anticline could well be faulted along the south- west flank. Asseez (1967) considered this a faulted system and depicts it as such on his lower Mississippian structure maps. In order to show the Howell Anticlire ad the Northville Anticline as a continuous trend, the writer has included the northern terminus of the Northville Anti- cline. The Northville Field itself is not included in this study, tIerefore, reference to Checkley (1968) is made when referring to that structure. The Howell Structure The present structural configuration of the Howell Anticline is shown by a set of three structural cross-sections (Figs. 6, 7, and 8) and mo contoured structure maps, Niagara (Fig. 10) and Dundee (Fig. 11). The two structure maps show the offset of structure with progression upward through the sedimentary column. The Howell Anticline most likely underwent its major uplift during the Mississippian or early R'7E RESE RESE R‘IE R555 R235 LI. , air. a HOWELL ANTICLINE LIWNGSTON COUNTY MKHHGAN MAGARA STRUCTURE CONTOUR INTERVAL = IOO' ' 4AMLES SCALE RPARE APRM_I977 IC FIGURE fie \\ I Ila—«Q! R77E RPARB HOWELL ANTICLINE LIVINGSTON COUNTY MICHIGAN DUNDEE STRUCTURE INTERVAL=IOO' I" - 4 MILES I977 CONTOUR SCALE- APRK RESE R5E§ HGURE H R<3E _ n _ LI: m l . RESE REZE 26 Pennsylvanian as the baserent responded to tectonic compression from the east as a harbinger of the oncoming Appalachian Orogeny. Regional dip on the Niagara (Fig. 10) Formation is approximately 100 feet per mile, slightly more than 1 degree to the north-northeast. 'Ihe anticlinal feature in the southwest corner Of the map is the northern terminus of the Lucas-anroe Anticline. On the Niagara, the Howell Anticline is drawn as a series of en echelon faults striking roughly N450W. The system plunges to the northvest. Increased control brings out the en echelon arrangement of the fault system. A regional study which uses only a few wells from each field will allow the fault to be drawn as a rather sinuous single fault. Relief across the Fowlerville Field is nearly 900 feet across the fault line. This represents the greatest amount of structural relief along the length of the Howell Fault zone. Throat on the fault block dies oit both to the northwest, into Shiawassee County, and to the southeast toward Green Oak field where relief across the fault line is less than 100 feet. Green Oak could easily have been drawn as a sharply dipping anticlinal nose with no faulting on its southwest flank. This area was interpreted to be faulted on the southwestern flank of the structure. The fault dies out to the southeast becoming an anticlinal nose. As this study covers only the northwestern terminus of the North- ville Field, Checkley's work of 1968 has been used for structural definition of the Northville Field. He shows the Northville Field to be faulted along the northeast flank. This faulting dies out to the rortl'mest becoming a steeply dipping anticlinal nose along its terminus 27 in this study area. Evidence for interpreting this system as a faulted system of anti- clires is primarily around the Fowlerville Field. Relief between the wells located in section 21 T4N R3E and 28 MN R3E is 756 feet, where the wells are a little under one mile apart. Also between the wells located in section 11 T3N R3E and NElZ T3N R3E the structural relief is 714 feet. The relief between these wells accounts for nearly all of the structural relief on the Niagara across the Fowlerville Field. Further evidence is found in the Helen Sober well located in SW35 T4N R3E. In this well from the lower portion of the Detroit River through the upper part of the Bass Islands (a sequence of 400 feet in rearby wells) is represented by 200 feet on the mechanical log. ‘Ihus, 200 feet are missing and tie log of the interval present is severly jumbled. The well located in NW of 18 T3N R4E also has a missing section of rock units. The A—2 carbonate in this well is missing. A missing section of salt could be accounted for as removal by solution but removal of a carboate perhaps is better explained as a result of faulting. Faulting along the southern flank of the Howell Field is a projection along the strike of this faulting. The pattern of faulting seen along the fault zone from the north- western limit of the map through the Northville Field area is represen- tative of a scissor-type fault motion. A scissor pattern of fault motion would tend to indicate wrench fault mechanics Operating within the basement corplex beneath the Howell Fault zone. As the basement responds to regional tectonic forces, most likely this would be a compressive force from the east due to an early pulse of the Appalachian disturbance, stress will be relieved along ancient zones of weakness. 28 In.Michigan the pattern of basement lines of weakness was probably set prior to the etplacement of the Keweenawan age basalts. 'Ihese basalts were probably intruded along pre-existing lines of weakness (Hinze and Phrritt, 1969; Kellogg, 1971). The Dundee structure (Fig. 11) , like the Niagara structure, shovs an en echelon system of faulted anticlines that strike gererally N450W and plunge basinward. The northern tenminus of the LucaSeMonroe Anticline is again seen in the southwest corner of the map. Structural relief over the fields is generally greater on the Dundee than.on the Niagara. Across the Howell Field the relief is 1279 feet on the Dundee, measured between the well in section 14 TZN R4E and the well in section 35 T3N R3E while the greatest relief on the Niagara was only 509 feet between the well located in section 14 TZN RAE and that in the NE of section 12 TZN RAE. Another noticable feature near the Howell Field is the large depression along the south side of the field. (It is through this area that.Ells (1969) chose to draw his cross section of the Howell Field). The faulting near Fowlerville is considerably more corplex on the Dundee horizon than.on the Niagara horizon. Across the Fewlerville Field the difference in structural relief between the two horizons is not nearly as noticable as across the Howell Field, being about 1100 feet of relief across FOwlerville on the Dundee and 900 feet on the Niagara. The Green Oak Field also exhibits greater structural relief on the Dundee, nearly 600 feet, than on the Niagara, less than 100 feet. The two dip structure cross sections (Figs. 6 and 7) show that the offset of the crest of the Howell Anticline on the Dundee horizon to the 29 northeast of the Niagara crest as noted by COhee and Landes (1958), can be attributed to the fault dipping to the southwest. The result.of the dipping fault plane is that the axial plane of the anticline also dips to the southwest. During uplift, drag along the fault resulted in the beds dipping toward the fault.immediately along the fault zone. The crest, on both the Dundee and Niagara, is therefore not directly adjacent to the fault but is slightly to the northeast of the fault. This drag is also apparent on the Niagara and Dundee structure maps, where it yields the appearance of left lateral motion. On the down thrown side of the fault, drag can also be seen as the beds dip upward toward the fault. A small anticline located in the northeast corner Of T3N RSE also can.be seen. This small anticline is probably a small wrinkle develOped during uplift along the Howell Fault. FUrther discordance of structures between the Niagara and Dundee horizons can be attributed to uneven response of the thick evaporite sections of the Salina and Detroit River Groups to the deformation of the Howell structure. The block along the south flank of the Fowlerville Field tilted, dropping down to the northwest. This block will be seen later to be acting independantly during deformation. Solutio1 and reIoval of the Salina salts will also account for the depression of the south side of the Howell Field. ISOPACHS ional During Cambrian time, Fisher (1969) shows an embayment of the Illinois Cambrian.depocenter in southwestern Michigan. A shallow depocenter of an early Michigan depression also occurs in the south- eastern portion of Ogemaw County. A.Trenton depocenter located near southern Lake Huron is shown by Seyler (1974). Seyler's Trenton basin is elongated toward the east and west. The Utica shale (Nurmi, 1972) is thinnest in western.Michigan, becoIes thicker tovard the east, and reaches a maximum thickness in Lenawee County. Nurmd also notes that the Utica thickens and thins in a pattern reflecting structures which show on Trenton structure maps. This pattern holds true across the Howell Anticline. This would tend to indicate a tOpographic or structural high along the Howell Anticline during deposition of the Utica. Another possible reason could be that these shales responded.more plastically during later uplift of the HOwell Anticline and were "squeezed" or thinned by compaction across the crest of the structure. Nurmi's Unit 5 shows a gentle thickening toward the north.with no reflection of the Howell Anticline. The Clinton thickens considerably northward until it looses defini- tion and grades into the overlying Niagara in the northern part of the southern peninsula according to Potter (1975). He also shows the Rochester shale to be thickest in St. Clair County thinning westward 30 31 until it pinches out near Lake Michigan. This pattern repeats toward the central part of the Michigan Basin where the Rochester is absent. Mesolella, et al, (1974) show a Barrier or Massive Reef complex of the Niagara surrounding the Michigan Basin margins. This Massive Reef attains a maximum thickness of just over 500 feet. Away from the.Massive Reef the Niagara thins very quickly basinward to less than 100 feet thickness in the central Basin area. The Arl Evaporite is thickest in the Basin interior and thins toward the Basin margins. The unit only partially fills in any topographic irregularities of the Niagara surface. The Arl Evaporite wedges out against the flanks of barrier and pinnacle reefs. The Arl Carbonate is also a "reefing" unit being thickest and dolomitized along the Basin margins becoming thinner limestones in the Basin interior. Where the Arl Evaporite is absent the Niagara and Arl Carbonate are grouped as an undifferentiated carbonate. The Ar2 Evaporite is thinnest along the Basin margin, wedging out near the Massive Reef zone, and thickens to just over 1000 feet near the Basin center. The Ar2 carbonate is "non-reefing" being thinnest along the Massive Reef zone and thickest toward the Basin interior. .Mesollela's, et al, work shows an interesting trend of deposition across the area of the Howell Anticline. The Massive Reef facies deposition of the Niagara is not continuous acrosstivingston County. The reef front turns west of Livingston County so that the reef front roughly parallels the strike of the Howell Anticline. The Arl Carbonate also thins roughly along this same line. The Ar2 Carbonate thickens parallel to the thinning Niagara and Arl Carbonate and thicken- ing Ar2 Carbonate indicates a deeper water environment altered the depositional pattern of these units across the area of Livingston County. 32 Majedi (1969) slows a broad lo» entering from the north across Livingston County during Detroit River time. This low is shown by a general thickening of the Detroit River Group toward tle northeast. Isopachs Of the Antrim, Bedford, Berea, and Sunbury by Asseez (1969) show no thickening or thinning of these units to reflect the existanoe of any structure in the area of the HoeIl Anticline during deposition of tlese units. The Antrim shale is thickest in the central Basin region and thins toward the west. The Bedford-Berea sequence is restricted to the eastern half of the lower Peninsula. This sequence is thickest toward eastern Michigan and thins out tmard a line running about rorth-south through the center of the state. Asseez terms the Bedford-Berea a prodelta sequence, with the sands of the Berea being bars and channel fills. Chung (1973) slows the Coldwater Formation to be offlapped on the Howell Anticline. The Coldwater appears to thin gradually toerd the Howell Anticline but it is very difficult to determire whether this Offlap is due to erosion or non-deposition, however, the greater off- lap of the overlying Marshall formation suggests truncation erosion along the post-Marshall disconformity. Howell Area The previous section describing the Hoell Structure depicted the present structural pictm'e of the Hoell Anticline. The Hoell Anticline has rot been a structural high througrout its past. Following is a set of isopach maps: Upper Cincimetian or Unit 5; Salina G to Niagaran; Dirdee to Salina G; Bell, Antrim, and Bedford-Berea. TWO restored stratigraphic cross-sections, one on the Salina G unit and the second 33 on the Bell Shale, also are used to deve10p an understanding of the developrental history of the Howell Anticline. [Mar Cincinnatian: The Upper Cincinnatian (Fig. 12) has the least amount of control. As the picks were made on the basis of log characteristics only those wells which were logged were used. The unit exhibits an uneven depositional pattern. Thickening toward the north and west reflects regional thickening into the basin interior. Nurmi (1972) suggests a period of erosion following deposi- tion of the Upper Cincinnatian. The irregular thickening and thinning seen in areas of thighter control is reflecting an uneven surface which could be attributed to post-depositional erosion of this unit. The Michigan Basin was probably fairly shallow during deposition of the Upper Cincinnatian and the Howell area was quite near the shore line, possibly an intertidal zone. The deposition of red and green shales with thin limestones indicate this type of environment. The red shales were likely deposited in an oxidizing environment, indicating shallow, agitated waters with erough oxygen to oxidize the iron in the clay particles. The green shales may represent slightly deeper water and higher organic content. Deeper water would allow layers of mud to be covered before there is a chance to oxidize the iron. More organic material woqu rob the oxygen during decay of the organic material to produce a reducing environment. The inclusion of limestones in this sequence indicate a fluctuation of water level as determining whether the environment is oxygen rich (oxidizing) or oxygen poor (reducing). The limestone indicates a more stable slightly deeper warm water environment. The whole sequence taken together would indicate II I , , 4.3!: U RPARS ISOPACH sleuES UNIT 5 1977 HOWELL ANTICLINE LIVINGSTON COUNTY MICHIGAN CONTOUR INTERVAL = 5' SCALE APRW Y2 FIGURE 35 an oscillating water level such as would be expected of a tidal flat or intertidal zone. Salina G to Niagara: Figure 13 is an isopach of the Salina Group of Cayugan time. During this time the Michigan Basin was undergoing deposition of thick evap- orites with interlayered carbonates and shales . This interval thickens gradually toward the rortheast until the line of the fault zone along the southwestern flank of the Howell Anticlire. At this line the Salina units thicken from 1300 feet to rearly 1700 feet over a short distance. Beyond the fault zone the units again thicken gradually into the deeper portion of the Michigan Basin. Except for the abrupt thickening across the fault zone, this interval thickens gradually toward the Basin interior. This change in slope of the depositional surface can also be seen in figure 14, the restored stratigraphic cross-section on the Salina G. Going across the fault, the F—Salt Unit thickens most between the Brazos-Kizer well and the Panhandle Eastern-Wilson-Bush well, which are on opposite sides of the fault. This would indicate that the greatest episode of subsidence along the rortheast flank of tie Howell Fault was contetporareous with F—Unit deposition . Fisher (1969) indicates the Salina time to be the major period of subsidence of the Michigan Basin. Figures 13 and 14 would tend to concur that subsidence was greatest during upper Salina time in tre area of Livingston County. Sudden thickening along the rorthwest diagonal of the map indicates that tle fault zone along which the Howell Anticline interforms was active during Cayugan time also. The rortheast block was subsiding during this time. This type of fault activity is termed ,i_¢_ R7E I l ‘ -~+~+~~+~w ‘f ‘ I 3 , I I +_-l- R6E I , _ -4_1,-.,L___ _ R55 R45 HOWELL ANTICLINE LIVINGSTON COUNTY MICHIGAN ISOPACH SALINA Ioo' INTERVAL= CONTOUR I" = 4 MILES SCALE: R PARIS I977 APRIL I3 FIGURE 37 F F' BRAZOS PEPL PEPL MOBIL KIZER I WILSON-BUSH l ITSELL l MESSMORE I 25868 I606? 267” 27986 SW sw NE SE NW NE NE NE NW NE I4 - ZN- 4: I2 ~2N- 4E 6- 2N-5E Il- 3N-5E ...;Jamm_ -_ I? _. twee- 2 . G __.__...———.-—_ -. -.--. . .— F E a ...I ‘ A-z CARaONATc ( I \ I "" -:: \ A-2 EVAPORITE \ ‘4 CARBON": \ NIAGARA -I v on \ x \ m: \ M _- _ _- __ c 'E If)” A l 50 00 10d Figure 14 . Restored Stratigraphic Cross Section Across Howell Field, Datum Salina G 38 growth faulting, wfen fault moverent is contemporaneous with sedimenta- tion, resulting in rapid thickening of the units along the fault line. As tensional forces acted on the Basin during the Silurian the baseIent rocks would readjust themselves along pre-set fracture of fault patterns. The primary moveTent would be vertical readjustment as gravity became the dominant force acting on the baseTent blocks . The Salina G to Niagara map indicates that the northeastern block did respond during the Cayugan epoch by subsiding with the greatest amount of subsidence occurring during deposition of the F-Unit. The anotalous thin area seen in section 7 TZN RSE is caused by solution and reroval of the Salina salts during later uplift of the Howell Region, as suggested by Ells (1969) . Collapse of the overlying beds would account for the depression on the Dundee surface. Lardes (1945) describes collapse of Salina salt caverns near the Straits of Mackinac with resulting brecciation of pre-Dundee beds. He dates this as a pre-Dundee phenoreron. Middle and Upper Silurian time is marked by deposition of alter- nating carbonates, evaporites, and shales within the Michigan Basin. A massive reef surrounding the Basin with patchy pinnacle reef growths or the basinward margin of this massive reef complex, followed by thin basinal limestones characterizes the Niagara. Following deposition of the Niagara, fluctuations in sea level are marked by cycles of evaporite and carbonate deposition through deposition of the A—2 Carbonate. Entrance of fresher waters is severely restricted during deposition of the B—Salt. The Michigan Basin retains gererally restricted until deposition of the lower Bass Islands dolomites. This marks a respite from the cyclical deposition pattern and a general return to more normal marine conditions . 39 Dundee to Salina "G": This map (Fig. 15) shows a general thickening toward the rortheast. Again the sharp tightening of contour lines along tle line of the Howell Fault zore indicates sore subsidence of the rortheast block during deposition of this interval. The restored stratigraphic cross- section (Fig. 16) on the Bell Shale datum shows that the majority of subsidence occurred during deposition of the Detroit River evaporite— carbonate cycle. The general thinning along the Fowlerville Field is probably caused by flowage of the Detroit River evaporites during later uplift. This sliver coincides with the tilted block on the Dundee structure. This block seems to have acted sotewhat independently during deformation . Deposition of the Bass Islands Group marks the end of the shallow restricted evaporite basin. The lower portion of Bass Islands is an anhydritic dolomite which represents a returning to more rormal marine cowditions of the Basin waters. It becotes more of a pure dolomite near the top. Normal marire water environments prevail until after deposition of the sylvania . The interlayered evaporites and carbonates of the Detroit River indicate a return to an evaporite basin. Deposi- tion of the Dundee limestone marks a return to a more Open marine enviroment within the Basin. These conditions prevail until deposi- tion of the Mississippian clastics begin to fill in the Basin. Bell: The Bell Shale isopach (Fig. 17) was drawn with a 2-foot contour interval. This smaller interval could lead to the interpretation of a complex depositional pattern, where in actuality the unit thickens very gently to the northeast with no sudden thickening across the fault ....stlsk E 7 H R NC E w M. N m 0 O I Csmv S L II m CM 2 M I Y S TTGMER N N A W m C U T 4 L 08 . T ETOWIW. So. W C OE TLIIL E OWENAR 6 HWMOCP R LNCSA U D E 5 . R h _ _ HILi " n . r _ l I--I.--I.-4_IL .. _ _ _ E R r n . III+I E i 4 l R 32,4 E 3 R T4N T3N T2N TIN TIS 41 G 6' BRAZOS PEPL PEPL MOBIL KIZER I WILSON-BUSH I ITSELL l MESSMORE I 25860 16067 26758 27986 SW SW NE SE NW NE NE NE NW NE I4- 2N-QE l2-2N-4E 6-2N-SE lI-SN-SE —— — L- L3 DAWN; ; I 5 4%!“ I‘ 42§Iy BELL é;- ounce: LUCAS E J- E SYLV‘NIA I BOIS BLANC L' g BASS ISLANDS ‘/ ‘3“ :3 SALINA c i I a 0-w- i a l 0.. Figure 16. Restored Stratigraphic Cross Section Across Howell Field, Datum Bell Shale ..II'I ISOPACH RPARm CONTOUR INTERVAL: z I"- 4IMLES BELL I977 HOWELL ANTICLINE LIVWCSTON COUNTY MunuGAN SCALE ApRu i7 FIGURE 43 zore. During deposition of tle Bell the rortheastern block is ro longer subsiding though it could still be sorewhat structurally lower. The corplex pattern across the Howell and Fowlerville Fields is partly a matter of control in tle field areas. The increase in calcareousnous of the Bell toward the west across this area would imply the source of clastics for the Bell to be from the East. A shale Lmit will be more coarsely clastic and thicker nearer tle soirce which provides the clastics, the fine clays settling wt in fairly quiet waters . Going away from the source area one would expect fewer clastics and more carbonate material deposited in shallow warm waters. The cotplex pattern of contours across the two gas fields results from closer cmtml. Tl'e Dundee surface upon which the Bell has been deposited is undoubtably more irregular than shown by the scattered control away from these fields. The Dundee surface should owe its irregularity to post-Dundee erosion, as suggested by Newcombe (1933) and Bloorer (1969). With the near proximity to the Michigan Basin edge of this area it would rot take a very dramatic drop in water level or rise along the Findlay Arch to expose this area to erosion. It is also possible, in the Howell area, that the irregularity of tle Dundee surface is in part a reflection of flowage and reroval of Salina and Detroit River evaporites. This suggestion is arrived at by emmining the location and trend of irregularities on the Dundee surface across the separate fields. The thickest Bell in tle Howell area, SE section 7 TZN RSE (Fig. 17) , coincides with the large Dundee depression (Fig. 11), and tle thin Salina interval (Fig. 13). That 44 these stould all coincide favors the thought that retoval of tle Salina salts is responsible for the relief of the Dundee surface in this area. The thin area along the Fowlerville Field (Fig. 17) coincides with the thinning of the Dundee to Salina G interval, and with the tilted block on the Dundee structure. This could be a thin block or sliver which has responded independantly to a gentle corpressive force which has halted the subsidence of tle main rortlern block. The response of this sliver has been a gentle pre-Bell uplift with a subsequent thin- ning of the Bell along this block. The evaporites of tle Detroit River Group could then have responded by flowing away from this zore of deformation with the resulting thin that is seen in this interval. Leaching and flowage of the evaporites of the Salina and Detroit River Groups can partially account for irregularities on the Dundee surface, which are in turn reflected on the Bell iSOpach map as irregular patterns of thick and thins. Antrim: The Antrim shale (Fig. 18) shows gereral thickening towards the rorthwest. This unit is a thick dark grey to black shale. It is very carbonaceous , heavily pyritized and radioactive . A shallow stagnent environent would produce the stagnent waters and reducing conditions which must have prevailed during deposition of tl'e Antrim. Near the southeast correr of tle map the Antrim subcrops beneath the glacial cover. Along tre strike of the Howell fault the unit varies in thick- ness, again perhaps a matter of more well control. If the fault zone was in motion as early as Dundee or Bell time it can be assumed that this motion was continued , trough perhaps episodically, througl'out deposition of the Traverse and Antrim. Cohee 7.55.}: .0. _ 5 7 ISOPACH INTERVAL=IO' 4IMLES RPARe I": I977 ANTRIM CONTOUR HOWELL ANTKHJNE LJVWCSTON COUNTY MKHHGAN SCALE APRm R65 R55 , .LLe I , . ---lL I8. FIGURE 0” 7, IHIr. R45 R35 R25 T5N T4N T3N T2N TIN TIS 46 (1947) suggests that there was notion along the major structural trends as early as Traverse time. The thin along the crest of the Fowlerville Field could indicate that this portion of the fault was high during Antrim time. The area in Green Oak township was also slightly high, structurally, at this time. The Howell Field is surrounded by a thicker deposit of Antrim than the surrounding area. It is quite likely that the early notions of the fault zone were not along a continuous line but were scmemat discon- tinuous. The Howell area would then have been a low or sag along the fault line which had not yet undergone uplift as the Fowlerville and Green Oak sections had, displaying differential mvement along the fault zone. Asseez (1967) sl’nws no strong thinning across the Howell Anticline on his regional Antrim isopach map. The minor relief created by these early novements would not stow on a regional map contoured on a larger interval. Another explanation would be karst development within the Traverse Group. Ells (1969) has suggested that a karst terrain was deve10ped on the Traverse. This might account for the brecciation that Newccube (1933) describes in the Traverse interval of the ‘Iboley well (although fault brecciation can not be ruled out) . Collapse into a cavern would result in brecciation of the overlying material. Karst terrain would also account for the irregular thickening and thinning of the Traverse in this area as noted by Runyan (1976) . As the Antrim was deposited upon this irregular surface the karst topography would be reflected by thickening and thinning of the Antrim. Across the area that Runyan notes his most irregular Traverse interval, the overlying Antrim shows 47 a poor matching of Antrim thicks with Traverse thins. As this irregu- larity of Traverse isopachs is most noticeable along the Howell Anticline, and the overlying deposition patter of the Antrim does not strongly suggest karst development of the Traverse, gentle irregular Hover-ant along the fault plane is suggested as the cause of both the Traverse and Antrim irregularities of thickening and thinning. Berea-Bed ford : This unit (Fig. 19) shows a general thickening to the southeast, tIDugh there is a considerable degree of unevenness of deposition. The extrene irregularities across the Howell and Fowlerville Fields are in part the result of increased control. The uneven surface undoubtably exterfls beyond the field limits but is not observable, owing to sparser control. This unit subcr0ps in the southeast corner of the map, and is offlapped along the northeast block of the Howell Anticline. The subcropping of this unit introduces sane ancmalous tlfinm'ng which was not contoured, as only control points of wells which contained the overlying Sunbury were utilized. Asseez (1967) terms the Berea-Bedford a prodelta sequence in the Michigan Basin. He notes that this prodelta does not extend beyond the eastern half of the lower Perfinsula. The uneven pattern of deposi- tion and the general lithologies of these units within the area of the Howell Anticline inply a progressive deltaic sequence during this time. The thinning across the Howell and Fowlerville Fields suggests that these areas were low-relief structural highs during deposition of the Berea-Bedford sequence. R6E RTE R35 R45 _ R55 20-4 Izcnq 200-1 ZN-Q 24-1 m-d HOWELL ANTICLINE meosron COUNTY MICHIGAN BEREA ‘ BEDFORD ISOPACH comoun INTERVAL . 10' SCALE- s'- 4 MILES APRIL l977 RPARIS FIGURE ‘9 SW OF DEVEIDPMENTAL HISTORY The structural grain of the basement beneath the.Michigan Basin is probably quite carplex. Western Ontario, in the region of the Grenville Front, is marked by a dominantly northeast-southwest structural grain with a northwest-southeast cross pattern within the igneous and metamorphic catplex of the Canadian Shield. The Shield is marked by an eastewest pattern east and north of the Upper Penninsula of Michigan. Southern‘Wisconsin also is marked by an eastdwest structural pattern. The structural grain in southern‘Western Ontario is also eastrwest. Cbntinuation.of these structural patterns of the surrounding areas beneath the Michigan Basin*would result in a complex structural grain within the basement rocks. Hinze and Merritt (1969) have suggested a.dhudnant northwest-southeast trend within the basement of the Michigan Basin, frrm interpretation of their gravity and magnetic surveys. They also suggest the Keweenawan age rifting would follow this (ixninant structural trend of basement weakness, allowing emplacement of thick basalts suggested as the source of the Mid-Michigan gravity and magnetic high. During the20rdovician, deposition within the Michigan Basin changed fioulthe:predcminant cambrian sandstones to a more typical sequence of carbonates and shales. Nurmi (1972) and Seyler (1974), both describe an.early formlof the Michigan Basin during the Ordovician. As deposition of the late Silurian Salina Evaporite cycle began, 49 50 the zones of basanent weakness responded to regional tensional forces and gravity by subsidence of fault blocks. Thickening of the Salina Group rortheast across Livingston County shows that the Howell Fault wasactive at this time with the northeast block subsiding thereby responding to the tens ional and gravitational forces . The northeast block remained structurally low throughout the early Devonian with same continued subsidence during Detroit River time. By Bell tine there was little or no relief across the Howell Fault marking the end of subsidence. Gentle caupressive force is indicated by a small degree of thinning of the Bell Shale implying gentle uplift along the Fowlerville Field. Gentle carpression continues to act on this area until at least Coldwater time. These movements which cul- minated in uplift of the when Anticline can be related to early stage or small displacerent wrench fault tectonics acting on the basement carplex. The present configuration of the Howell Anticline, as depicted on figures 10 and 11, reflects a pattern of structural features (Fig. 20) which can be attributed to wrench fault mechanics. Release of stress along the Howell Fault has resulted in vertical uplift of the northeast block along the fault zone with little lateral offset. Harding (1974) describes the Albion-Scipio oil field trend as a pattern which represents a stage of wrench faulting during which slight left-lateral displacement of the basement carplex beneath the area has occurred. Prouty (1976a, 1976b) has extended the concept of wrench fault tectonics to apply throughout the Michigan Basin and shows a close correlation between the azimuths of linear oil fields and shear patterns related to carpression from a general eastward direction. Thcmas (1974) 51 850% page EH3 “roam 395m Scum mfiuasmmm monoumom Hmuduoaum .om .3de Bondage cannon Em mwusuomum Human 8.85m coeuoono mmmHum Hmucofiuon 3305.5 \ Ag young 33cm 6:83 puma 588cm messaged cowmcou mega p.33 £9893 puma Honcho uwfim :3: can. €82 swung magnum £98“), puma Hmouo ncooom ......V moHomemm / 52 in a study of the structural features of the Williston—Blood creek Basin suggests that this area has been subjected to catpressional sim- ple shear mechanics. According to Thanas the basement beneath the Willistcn-Blood Creek Basin is not an unbroken carpetant neditm, but rather a fairly complexly fractured basenent.which would divert any applied stress along these basement lines of weakness allowing con- pressicnal sinple shear block coupling mechanics to predominate. The.Midhigan Basin basement also can be expected to have a fairly complex structural pattern as suggested by Stockwell (1965) and Hinze and Merritt (1969). Stockwell describes the structural grain of the Canadian Shield. Hinze and Merritt suggest the structural grain beneath the Michigan Basin. During the incipient stages (Thomas 1974; Wilcox, et al, 1973) of a left lateral couple, para-fOIds would develop (Fig. 21a). As the catpression continues, the axes will be rotated counterclockwise (clockwise in a right lateral shear couple), toward the direction of the shear couple (Fig. 21b). With the Albion-Scipio trend to be generally agreed upon as lateral strike-slip novement (Harding, 1974; Fisher, 1969; 3113, 1962), this trend is probably a reflection of deep seated wrench fault tectonics as suggested by Harding; This model, with the modification of being a less intense stage of deformation, can be assumed to apply to the features associated with the Hewell Fault systenu The offset en echelon anticlines of the Howell, Fowlerville, Northville, and Green Oak Fields have axes which are rotated to nearly parallel the general strike of the basement fracture patterns along which the lateral motion of the wrench zone would occur. Faulting along the southwest side may 53 A. Incipient B. Advanced Figure 21 . Progression of Axial Plane Rotation During Simple Shear Deformation (after MS: 1974) Lineament simple shear produces block coupling resulting in parafolds with the associated flank faults and cross- fold tension. Incipient and advanced stages apply to degrees of axis rotation, not degree of wrench motion. 54 have begun as normal faulting with.dips to the southwest and continued with eventual uplift of the northeast block during later stages of this deformation. Cross faults, possibly the shear couples, or pinnate tension fractures, would develop at nearly right angles to the fold axis. Ells (1969) drew such a cross fault on his Niagaran structure. This type of feature would provide channel ways for the solution and removal of the Salina salts on the south side of the Howell Field which resulted in the large depression on the Dundee structure. The small anticline located directly northeast of the Howell Field would then be a smaller para-fold along the en echelon trend, without the attendant faulting. Additional evidence of this being a wrench fault-related system lies with the faulting of the Northville Anticline. Checkley (1968) interprets the Nbrthville as faulted along its northeast flank on both his Niagaran and Trenton structures. With the die out or loss of throw on the Niagara in Green Oak Township being near the location of the pivot point of the fault system, the entire system from Northville Field to Fewlerville Field can be interpreted as a scissor fault. The wrench fault system has not progressed to the stage of lateral offset of facies in this area. (Harding, 1974, suggested leftrlateral offset along the Albion-Scipio wrench fault system.) Kilbourne (1947) does indicate some offset of Coldwater facies but this is based on relatively few'wells. Evidence of considerable left-lateral movement is lacking along the Hewell Fault. Mesolella, et al, (1974) have an extension of basinward facies of the Salina and Niagaran units into livingston county near the Howell Fault systemt This extension is opposite that which would be expected of any significant left-lateral 55 motion, that is, the marginal facies should be extended basinward as you cross the fault zone to reflect left-lateral motion. The extensive offset as suggested by the Bedrock of Michigan geological map would be better explained as erosional offset along regional dip of the north- eastern uplifted block of the Howell Anticline. OIL AND GAS PK)DUCI‘IQ\I* Earliest indications of oil and gas associated with the Howell Anticline were reported by Smith in 1834, (in Newccmbe, 1933) northwest of the city of Howell. later in 1893, lane mentions considerable shows east of Howell. Shows of oil and gas in shallow water wells have been reported since that time to the present. By the early 1930's many Bereaandseveralumdee testshadbeendrilled. Onlyshowswere recorded with no camercial quantities of oil or gas. host of the Berea wells were deep water wells. One well, the Rabb, drilled by Norris and Smith in 1928, had gone into the upper Salina beds. This well was drilled in section 26 of Oohoctah Township. First discovery of significant quantities of gas was in 1935. The Duck lake Oil Oarpany commenced drilling, on the tbPherson farm, NW35 T3N ME, in Septerber 1934, am catpleted the well in March 1935. The well was carpleted open hole with initial production of 478 DCF of gas. The 1930's had a very limited market for natural gas, the primary use being to reinject the gas into oil reservoirs for pressure maintainance, resulting in plugging and abarrloment of this well. In October 1946, Panhandle Eastern Pipeline Company carpleted the mPherson #1 SE35 T3N ME for 8,000 MIF of gas from the Guelph or Brown Niagara dolomite. *Production figures are from Annual Statistical Summary 24, Michigan Oil and Gas Fields 1975, published by the DNR Geology Division, Novetber 1976. 56 57 Development proceeded rapidly thereafter until 1950 when 16 wells were prodtrzing gas and light condensate from the Guelph. (hmulative produc- tion from the field was 23,678,129 LCF of gas before the field was switched to a gas storage reservoir in 1962. Production is from the Guelph, the browm dolomite associated with the reef buildups in the mrthern and southern Niagaran reef play. Ells (1969) suggests the dolomite reservoir might be a low relief reef buildup of Brown Niagara along the crest of the Anticline. This is doubtful as the maximum thickness of Brown Niagara over the Howell Field is 12 feetwhiletteminimummightbe 11 feet. Bothofthesevalues are within the regional "inter-reef" thickness of Broom Niagara for this area. GasandoilhavebeenproducedinNorthville Field. Production cores from the Dundee, Salina-Niagara, and Trenton-Black River. Dis- coveryofNorthvillewas inNovetber 1947wlentheHeath #lmganwas cotpletedasaDundeegaswell. Taggartcotpletedthexehrlin December 1954 to open production of the Salina-Niagara. Earlier, in January, 1954, Taggart had cotpleted the Ieloaster well beginning produc- tion of the Traitor-Black River reservoir . ProductionfromtheDm’deewasmtsignificantexoughtotamlate but came from 4 wells offset from the deeper production. The Salina- Niagara produces 3,794,518 LCF of gas with small amounts of oil from 10 wells. Trenton-Black River production has been the most prolific in Northville yielding 1,075,702 barrels of oil and 14,332,358 [CF of gas from 50 wells. In 1945 Shell drilled the Wilkinson, SW36 T4N R38, as a Niagaran test hole. This well was plugged after straws of gas from the 58 Salina-Niagara and test flows of 280 DCF and 179 MIF of gas and shows of oil from the Dundee. It is interesting to note that this well was drilled on the Dundee crest and just off of the Niagara crest. Humble then drilled the Soule unit #1, NEZ T3N R3E, to record the discovery of the Fowlerville Field in August, 1961. Fowlerville produces from the Salina Arl Carbonate and the Brown Niagara. A.tota1 of 18 wells have produced 1,419 barrels of oil arri 1,848,503 In? of gas. The majority, 1,360,565 MCF of gas and all oil being produced in 1975 after Michigan Consolidated Gas Corpany acquired the field as a shut-in gas reservoir awaiting commercial line tie-ins. Texaco is credited with.disoovery of the Green Oak Field after ootpleting the Kish #1, SW14 TlN R6E, in November, 1967, for 15 barrels of oil per day from the Trenton-Black River dolomites. Shows of gas were reported from the Dundee and Niagara, and a show of oil were reported from the Dundee. This one well field produced 2,836 barrels of oil before being abandoned in 1970. Cheokley (1968) notes that the Dundee production in the Northville Field is offset to the production.fromtthe deeper zones. It is possible that this production is fromlthe:crest of the Dundee structure which is offset to the deeper structures. This pattern.of structural offset is not inoonsistant, as over both the Fowlerville and Howell Fields the Dundee anticlinal crest is to the northeast of the Niagaran anticlinal crest. It is from this pattern of structural offset that the writer has interpreted the dip of the Howell Fault system to be to the south- west near Howell and Fowlerville (Figs. 6 and 7). Hydrocarbon reservoir potential of the Howell Anticline was greatly enhanced by the faulting which acootpanied the folding of the Anticline. 59 Porosity and permeability of the Trexton and Niagaran productim horizons is rather well limited to the fault zone. Away from the fault zonebothTrentonandNiagaranreservoirrocksgradetoadense, tight carbonate. Toward the fault zone porosity and permeability increase becoming intercrystalline to pinhole porosity to occasional vuggy porosity. Intercrystalline and interconnections of porosity give rise to good permeabilities. This reservoir quality, good porosity and permeability, probably developed in response to stress applied during faulting. Pressures associated with the faulting most likely crushed or fractured the morally dense carbonates, formational waters, or artesian waters as suggested by Newtart (1976) and Runyon (1976) , could then enhance porosity while percolating along these fractures develop- ing PinhOle and vuggy porosity. Source material for the Trenton-Black River productim could be the Utica shale. mile this shale is stratigraphically higher than the Trenton reservoir, it is structurally lower near the fault zone. Migratimofhydrocarbmsooildtakeplaoealoigtlefaultzoeto beoore entrapped in the Trentm reservoir (Fig. 22) . ArothersoiroeooildwellbetheTrentmitselfortleBlack-River Shale zone. The Trenton-Black River sequence has several organic rich intervalswl'uchooildactassoiroefortlehydrocarbms (13113, 1962). AsolroefortheNiagaraproductioaissoravtathardertolocate. 'metpperCimimatianisagoodcaIflidatebeingathick shale sequence. Migratiozupwerdofhydrocarbmsaloxgtrefaultzorewould behaltedbytheA-l Exeporitewhiohwoildbe less likelyto fracture and more likely to flow during defamation A closer am! more likely source is thestructurally lowA-l Carboateon thedom thrownblook 60 cmcmwnuu _, _._—_—_—' neuron —"-.'— unca Z;I ! : Figure 22: Possible migratim of hydrocarbons from stratigraphically lowerUticatostneoirallyhiglerTrentmalongafmflt plate. 61 of the fault. The A-l Carbonate is a very organically rich unit, so much so that the algal laminations of this unit have led it to be termed the "poker chip shale". During corpaction the associated heat and pressures would urrilcmbtably be sufficient to generate hydrocarbons. Gas and light condensate could migrate upward along the fault zone and became entrapped in the Niagara dolomite along the upthrown side. The B-Salt of the down thrown block against the A-2 Evaporite (Fig. 6) would act as a barrier to further upward migration and eventual loss of tle hydrocarbons from the Niagara horizon. Tte production of light condensate in the Niagaran and Salina A-l Carbonate in the Howell area indicates that the maturation of hydrocarbons has not progressed to the dry gas stage. In fact it irriioates that the shallow basin rim production is of early stage development of hydrocarbons. Tie central basin region should have potential for deeper production of Silurian age hydrocarbons. Tie association of high pressure gas, tle Gulf-Bateson well drilled in Kawkawlin Field, Bay County, and tie deeper development of Akron Field, Tuscola County, with Salina A-l or Niagaran reservoirs within tle central Michigan Basin region deronstrate this potential for deeper hydrocarbon production in this region. The develogrent of central Basin reservoirs should follow a pattern of wrench fault mechanics responding to simple shear stresses acting upon tle basement as modeled after development of the Howell Anticlire. CDNCLUSIONS Since Newconbe first described the Howell-Owesso Anticline as a faulted structure there has been debate as to whether this feature is a faulted anticline or a steeply dipping asymmetrical anticline. The evidence available to this study indicated that the Howell Anticline is a series of en echelon anticlines faulted along the southwest flank. This fault zone is part of the same system as the Northville Anticline which is faulted along its northeast flank. Together the Howell Fault zore and the Northville Anticlire are a system of faulted parafolds developed in relation to corpressional simple shear wrench fault mechanics acting on basetent lines of weakress beneath this area as stress is applied from the east during the oncoming Appalachian Orogeny of Mississippian time. This same compressional stress is responsible for developing the reservoir qualities of the Howell Anticlire. Fracturing along the fault zone of the normally dense tight carbonates during compression developed the porosity and permeability recessary for the accumulation and sub- sequent economic removal of stored hydrocarbons . It seems reasonable to extend this model of wrench fault mechanics into the central Michigan Basin Area. The many northwest-southeast trending anticlines would occur along minor zores of basement weakness whereas the Howell Fault zone developed along a major zone of basement weakness . 62 63 The Howell Anticline has not always been a structural high. During tle late Silurian the northeast block was downfaulted in response to regional tensional forces and gravity. This area retained structurally low until it underwent uplift during the Mississippian. BIBLIOGRAPHY BIBLICERAPHY Asseez, L. O., 1967, Stratigraphy and Paleogeography of the lower Mis- sissippian Sediments of the Michigan Basin: Unpublished Ph. D. Thesis, Michigan State University. Asseez, L. 0., 1969, Paleogeography of lower Mississippian Rocks of the Michigan Basin: Am. Assoc. Petroleum Geologists Bull., v. 53, H). 127-1350 Babb, C. S., 1969, Geologic Interpretive Study and Data Resource Evaluation of the St. Clair and Macomb Counties, Michigan, Subsur- face, 1969: Unpublished Master's Thesis, Michigan State Univer- sity. Blcoter, A. T., 1969, A Regional Study of the Middle Devonian Dundee Dolomites in the Michigan Basin: Unpublished Master's Ttesis, Michigan State University. Checkley, W. G., 1968, Northville Field: Oil and Gas Symposium, Mich. Basin Geol. Soc. Special Publication, pp. 115-122. (mung, P. K. , 1973, Mississippian Coldwater Formation of the Michigan Basin: Unpublished Ph. D. Thesis, Michigan State University. Cohee, G. V., 1947, Cambrian and Ordovician Rocks in Recent Wells in Southeastern Michigan: Am. Assoc. Petroleum Geologist Bull., v. 31, pp. 293-307. , 1948, Cambrian and Ordovician lbcks in Michigan Basin ani Adjoin- ing Areas: Am. Assoc. Petroleum Geologists Bull., v. 32, pp. 1417- 1448. , and Iandes, K. K., 1958, Oil in the Michigan Basin in Habitat of Oil: Am. Assoc. of Petroleum Geology Symposium, pp. 473-493. , 1965, Geologic History of the Michigan Basin: Journal of Washington Academy Sciences, v. 55, pp. 211-223. Dallmus, K. F., 1958, Mechanics of Basin Evolution ard its Relation to the Habitat of Oil in the Basin - Habitat of Oil: Am. Assoc. Petroleum Geologists Bull., v. 42, pp. 883-931. 65 66 Davey, D. E., 1958, A techanical and Chemical Analysis of tie Middle Devonian Detroit River Group Above the Sylvania in tle Michigan Basin: Unpublished Master's T‘l'esis, Michigan State University. Dice, B. B., 1955, A Quantitative Study of Composite Devonian Litho- facies in the Michigan Basin: Unpublished Master's Thesis, Michigan State University. Ells, G. D., 1962, Structures Associated with the Albion-Scipio Oil Field Trend: Michigan Dept. of Conservation, Geological Survey Division. , 1969, Architecture of the Michigan Basin: Mich. Basin Geol. Soc. Annual Field Excursion, pp. 60-88. , 1967, Michigan's Silurian Oil and Gas Pools: Geol. Surv. Div., DNR, State of Mich., Report of Invest, no. 2, pp. 1-49. Fisher, J. H., 1969, Early Paleozoic History of the Michigan Basin: Mich. Basin Geol. Soc. Annual Field Encoursion, pp. 89-95. , et al, 1969, Stratigraphic Cross-Sections of the Michigan Basin: Michigan Basin Geol. Soc., Special Publication. Fincham, W. J., 1975, The Salina Group of the Southern Part of tie Michigan Basin: Unpublished Master's Thesis, Michigan State University. Gill, D. , 1973, Stratigraphy, Facies, Evolution and Diageresis of Productive Niagaran Guelf Reefs and Cayugan Sabkha Deposits, T’re Belle River Mills Field, Michigan Basin: Unpublished Ph. D. Thesis, University of Michigan. Harding, T. P., 1974, Petroleum Traps Associated with Wrench Faults: Am. Assoc. Petroleum Geologists Bull., v. 58, pp. 1290-1304. Hinze, W. J ., 1963, Regional Gravity and Magnetic Anotaly Maps of the Southern Peninsula of Michigan: Geol. Survey of Mich., Report of Invest., re. 1. and Merritt, D. W., 1969, Basetent Rocks of the Southern Peninsula of Michigan: Mich. Basin Geol. Soc. Annual Field Excursion, pp. 28-59. , Merritt, D. W. and Kellogg, R. L., 1971, Gravity and Aerorag- retic Anotaly Maps of the Southern Peninsula of Michigan: Geol. Survey of Michigan, Report of Invest. , re. 14. Jodry, R. L., 1954, Reflection of Possible Deep Structures by Traverse Group Facies Charges in Western Michigan: Am. Assoc. Petroleum Geologists Bull., v. 41., pp. 2677-2694. Keck, W. G., 1937, Geophysical Measurerents in Livingston County: Mich. Acad. of Sci. Papers, v. 23, pp. 463-476. 67 Kellogg: R. L., 1971, An Areoragnetic Investigation of the Southern Peninsula of Michigan: Unpublished Master's Thesis, Michigan State University. Kilbourne, D. C., 1947, The Origin and Development of the Howell Anticlire in Michigan: Unpublished Master's Thesis, Michigan State University. Landes, K. K., Ehlers, G. M., and Stanley, G. M., 1945, Geology of the Packinac Straits Region: Michigan Geological Survey, Div. Pub. 44, Geol. Ser. 37. , 1948, Structure of Typical American Oil Fields: Am. Assoc. 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R., 1973, Basic Wrench Tectonics: Am. Assoc. Petroleum Geologists Bull., v. 57, no. 1, pp. 74-96. APPENDIX i 3|- $39 ZQUWHVECDE APPENDIX LIST OF WELLS USED FOR ISOPACH AND STRIJCIURECWIOURMPS Permit Nmber Sunbury Berea-Bedford Antrim Traverse Bell mndee Salina G Niagara - in area of Pinnacle Reef A-l Carbonate and Niagara are grouped together as an undifferentiated carbonate Clinton UpperCincinnatian-UnitS-top Upper Cincinnatian - Unit 5 - base Wellretlogged 71 72 nbmn wean IIII ommH IIII nonH hood omo mvm mm mnm nhNNN mnIZHIon 3m mm 3m... no.3. 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Imnmo m 25322 22 omooouoo l'I III 76 eoom ooom ooom ooom omoo meoo oooo omeo eeoo oooo mmoo o3 moo moooo moIzmImo mm 3m oooe oooo oooo oooo moeo mooo oooo omoo mm ooo ooomo moIomIoo 32 E39. ooom oemm mmem moom momo mmoo oooo oooo omoo oomo oomo omo moo moooo moIzmIom 3m 3m oomm mmem omom omom emeo oooo omoo oooo momo oomo momo ox oeo ooooo moIzmIm 32mm mm eoom ooom ooom meoe mmoo oooo omoo oooo ooeo mooo oooo o2 mmo ooooo moIomIm m2 mm moom eoom ooom mooe oooo omoo oooo ooeo mooo oooo oooo omo eooo mmmoo moIzeIo o2 m2 moom oooe oooo omoo oooo mooo eooo oooo oooo o2 meoo omooo mmIzeIoo 323232 mooe eooo emoo oomo oooo mooo oooo mooo 6o omoo moeoo mmIzeIoo mz m2 mm oooe oooe oooo oomo eoeo meoo eoo eoo ooo o2 meo moooo mmIzeIoo 3m 3m mm omoe oooo oooo eooo ooo oem ooe meo moo ooo ooooo moIzeImo 3m mm 32., oooo oooo ooo ooo oom moe omo ooo ox meo ooooo moIzeImo 3m 3m m2 oooo oooo ooo ooo mem oee ooo omo oeo ooo ooooo moIzeImo mm eooe omoe ooom eooo meoo ooo oom omo meo Bo moo eooeo moIzoImo 32 oooo oooo omoo oooo oooo ooo moo ooo ow ooo ooeoo moIzeImo 3m oome omee eooe emoe omoo emmo oomo oooo oooo moo omo oeo ooo oemoo moIzeIoo oz 32 m2 omoe oeeo mooo emoo eooo moo omm mem m2 ooo mmooo onzeIoo 32 xm m2 oeoe oomo omoo oooo ooo omm eom ooe omo oeo ooooo moIzeIoo 3m 3m m2 meom ooom ooom mooe mooo oooo omoo oeoo oomo eooo omoo m3 moo oommo moIzeIoo 3m 3m 3m oome mooe I moeo omoo oeoo ooo oem mom mm ooo oeooo ..ooIzeImo m232 mm. mm o.Im Ho 2 o a m .o. o m m E58 2m 5363 "IIIIIIIIII'IIIIIIIII