Project Full Name：Formation Mechanisms of High-Quality Marine Shale Reservoirs in Southern Sichuan and Key Technologies for Intelligent Evaluation and Applications

Company：

PetroChina Research Institute of Petroleum Exploration & Development ,

China University of Geosciences, Beijing., 

PetroChina Zhejiang Oilfield Company Exploration and Development Research Institute

Awarded： Exploration & Production Technology

Standard:  International  Advanced Level

Project Number：ECF-2024-SEP-1010

Principal Accomplishers： Shi Zhensheng, Zhou Tianqi, Dong Dazhong, Zhou Changbing, Zhao Qun, Zhao Xinsheng, Qi Ling, Zhao Deng, Li Jiangwei, Gu Xiaomin, Yu Yuanjiang

Key Innovation Points：

Shale gas is a key component ofChina's strategy to increase natural gas reserves and production. Asthe country's first large shale gas field with over one trillion cubic meters ofreserves and annual productionexceeding ten billion cubic meters, the Southern Sichuan shale gas field faces challenges in understandingreservoir characteristics and low-efficiency identification methods, which are crucial to the nation's energysupply. This projeet clarified that the marine shale in Southern Sichuan formed in a transgressive muddyshelf environment, revealing that three types of high-quality reservoirs-sedimentary, diagenetic, andffacture-are controlled by high-firequency sea-level changes, carly diagenetic biogenic quartz dissolution,and hydrocarbon generation-induced fiacture networks. Additionally, it developed intelligent predictiontechnology for identifying high-quality reservoirs in highly mature to over-mature marine shales.

Main Application and Technical Principal： 

This achievement integrates traditional reservoir geology with artilicial intelligence methods.facilitating the discovery oftrillions of cubic meters of proven shale gas reserves in the Changning, WeiyuanYuxi, and Zhaotong regions of Southern Sichuan. It has also accelerated the development of an additiona10 billion cubic meters of shale gas production capacity, The intelligent identification method for highquality shale reservoirs has significantly enhanced the identification rate and success rate of reservoirpredictions. This provides strong technical support for national oil and gas re form, the development of shalegas industry policies and standards, and natural resource planning. The project has also trained a newgeneration of shale gas exploration and development professionals, delivering significant economic andsocial benefits with promising prospects for wider application.

Technology Application： 

The research results of this project have been widely applied in the target evaluation and selection of favorable shale gas zones in the southern Sichuan area, the selection and evaluation of shale gas sweet spots and sweet zones, the preparation of shale gas development plans, and the construction of the discipline of fine-grained reservoir geology.

In terms of target evaluation and selection of favorable shale gas zones, according to the understanding that “sedimentary high-quality reservoirs are distributed in the sedimentary microphase of deep-water depressions”, with the help of the high-quality reservoir intelligent evaluation system developed in this project, and by adopting the single-factor analysis and multi-factor integrated mapping technology and the shale high-quality reservoir prediction and automatic mapping technology, we have pointed out that the upper system of the Chongqing area has developed nearly 2,000 km' of high-quality reservoirs with a resource capacity up to 400x108 km', which is the highest quality reservoir in Chongqing, with a resource capacity up to 400x108 km'. It has pointed out that the upper stratigraphic system in Chongqing has developed nearly 2000 km? and the resource capacity can reach 400x108 km' of high-quality shale reservoir development area, which has been confirmed by the exploration practice.