Sequence development, depositional filling evolution, and prospect forecast in northern Aryskum Depression of South Turgay Basin, Kazakstan

Jurassic to Cretaceous clastic rocks of the South Turgay Basin were deposited in the typical Mesozoic rift basin formed during the late Triassic collision between the Kazakstan and Siberia plates. In this study, we used more than 140 wells and 2400 km2 of 3D seismic data in the northern Aryskum Depression to produce a detailed sequence stratigraphic interpretation of the South Turgay Basin. Guided by sequence stratigraphy, sedimentology, and structural geology, lower Jurassic-lower Cretaceous strata of the northern Aryskum Depression in the South Turgay Basin, Kazakhstan were subdivided into 10 third-order sequences based on geological and geophysical data. Combined with tectonic evolution characteristics, sequence developments in the basin can be divided into four stages: early rift stage (SQ1–SQ3), late rift stage (SQ4–SQ6), fault to depression transition stage (SQ7–SQ8), and depression stage (SQ9–SQ10). Through comprehensive analysis of seismic sequence configuration, sequence stacking pattern, and dep...