The Mangystau Region, in southwestern Kazakhstan, is a region of complex structure resulting from terrane collision and rifting in the Late Paleozoic to Early Triassic. The crustal and upper mantle structure was intensely studied with seismic methods during the 1960's, producing competing interpretations. In 2016, Michigan State University and the Institute of Geophysical Research of Kazakhstan installed 10 broadband seismic stations throughout the region for about 20 days. With the data collected, receiver functions were produced and inverted jointly with surface wave dispersion curves to create shear wave velocity models that estimate the crustal structure. The results are interpreted as a sedimentary basin that is 3 km in North Ustyurt and Central Mangyshlak, and thickening to 5 km in South Mangyshlak. The Permian-Triassic Complex is found throughout all the Mangystau region varying in thickness; 7.5 km in North Ustyurt and Central Mangyshlak, and 4 km in South Mangyshlak. The granitic upper basement thickens from 10 km in North Ustyurt to 13 km in Central Mangyshlak and South Mangyshlak. Since the Moho is not clear in this study, the basaltic lower basement thickness is unknown. Results are in general agreement with prior studies, although some differences exist, perhaps induced by the smoothing parameter during the joint inversion causing sharp boundaries to be smeared in the results. More seismic data is necessary to study this region thoroughly with this inversion method.
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