The Huimin (惠民) depression is a third-level tectonic element of the Bohai (渤海) Bay basin in eastern China. The central uplift belt is the most important oil and gas accumulation zone in the depression, but the lack of adequate geological studies in the area has greatly hindered exploration and development. In this article, using seismic data, fracture mechanics, and a combination of data on fault growth indices and fault throws, we present an analysis of tectonic activity in the central uplift belt and adjacent regions. The amount of extension is calculated along balanced N-S cross-sections, along with the thickness of strata eroded from the fourth, third, and second members of the Shahejie (沙河街) Formation (Es4-Es2) in the uplift belt, by analyzing porosity and stratigraphic correlations. In addition, uplift features are described, and their timing and processes of formation are analyzed and dis-cussed. The results indicate that strike-slip and extensional tectonic movements coexisted, with the effects of the latter most obvious. The spatial and temporal nature of the extensional move- ments is varied: fault activity during the period Ek-Es4 was the strongest on the northern Ningnan (宁南) fault, and activity in the western part of the area was stronger than that in the east, which in turn was stronger than that in the central region; during Es3-Es2, the strongest fault movements were along the eastern part of the middle Linyi (临邑) fault, and activity in the western part of the area was rela-tively weak, whereas in the mid-west it was the strongest. The extensional movements were a response to the activity of the faults. The sediments in the lower part of the fourth member of the Shahejie For-mation (Es4x) show that Es4 was the time when the central belt first began to be uplifted strongly. Uplift was uneven during the Paleogene: the western part of the area was uplifted continuously, while the mid-eastern area underwent alternating periods of uplift and subsidence. During the Paleogene, a num
