Types and Characteristics of Sedimentary Facies of the Chang 7 Oil Reservoir Group in Heshui Area of the Ordos Basin

Bingni Li; Qinlian Wei; Pengcheng Sang; Liang Chen; Yanxin Bao; Chengqian Tan

doi:10.54691/gyrsr804

Authors

Bingni Li
Qinlian Wei
Pengcheng Sang
Liang Chen
Yanxin Bao
Chengqian Tan

DOI:

https://doi.org/10.54691/gyrsr804

Keywords:

Heshui Area; Chang 7 Oil Reservoir Group; Sedimentary Facies; Gravity Flow Deposits.

Abstract

The Heshui area is located in the Longdong block in the southern part of the Ordos Basin. It is an important exploration and development zone for the Chang 7 oil reservoir group, which is dominated by low-permeability and tight oil reservoirs and has huge resource potential. The Chang 7 oil reservoir group belongs to the Triassic Yanchang Formation (T3y) and is one of the main source rocks and reservoirs in the Ordos Basin. Based on the identification marks of sedimentary facies, as well as the analysis of core samples, comprehensive mud logging data in the study area and previous research results on regional sedimentary facies, this study shows that the Chang 7 oil reservoir group in the Heshui area is mainly composed of channel-type gravity flow deposits, with the development of subfacies types such as near-source channels, far-source channels, bank deposits, front lobes, and semi-deep lake-deep lake.

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