Origin analysis of paleo-overpressure in source rocks based on logging response characteristics: a case study of the Chang 7 member in the Triassic Yanchang formation, Longdong area, Ordos Basin, China

• DOI: 10.3389/feart.2024.1289510
• Publication Date: 2024-02-15T05:34:07Z
• Authors: Kaitong Xu; Yujia Huang; Minggang Tang; Jiahao Wu; Tengfei Ma
• Keywords: Overpressure; Sichuan basin

The identification of the origins source rock palaeo-overpressure based on logging response parameters is frequently influenced by presence organic matter. To accurately identify paleo-overpressure origin rocks and employ an appropriate method for paleo-pressure calculation, this study proposes a quantitative approach to assess influence matter content overpressure analysis. findings demonstrate that in Chang 7 shale leads increase acoustic time difference decrease density. After incorporating multi-component equivalent volume model correction, it evident observed member not attributed undercompaction but rather fluid expansion mechanisms. In conjunction with velocity-density palte method, resulting from hydrocarbon generation. pressure evolution has been reconstructed its origin. distribution characteristics recovered generation exhibit strong correlation reservoir. reliability correction demonstrated. proposed only applicable investigation paleo-pressure, also holds significant implications assessment within organic-rich intervals.