Reformation of deep clastic reservoirs with different diagenetic intensities by microfractures during late rapid deep burial: Implications from diagenetic physical simulation of Cretaceous Qingshuihe Formation in the southern margin of Junggar Basin, NW China  

作　　者：JIN Jun XIAN Benzhong LIAN Lixia CHEN Sirui WANG Jian LI Jiaqi 

机构地区：[1]Research Institute of Experiment and Detection,PetroChina Xinjiang Oilfield Company,Karamay,Xinjiang 834000,China [2]CNPC Key Laboratory of Conglomerate Reservoir Exploration and Development,Karamay,Xinjiang 834000,China [3]Xinjiang Laboratory of Petroleum Reserves in Conglomerate,Karamay,Xinjiang 834000,China [4]College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China [5]State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China

出　　处：《Petroleum Exploration and Development》2023年第2期346-359,共14页石油勘探与开发（英文版）

基　　金：Supported by the National Natural Scienceof China (41872113,42172109,42172108);National Key R&D Plan Project (2018YFA0702405);Special Science and Technology Program for Strategic Cooperation Between China National Petroleum Corporation and China University of Petroleum (Beijing)(ZLZX2020-02);China University of Petroleum (Beijing) Research Initiation Fund Project (2462020BJRC002,2462020YXZZ020)。

摘　　要：Constrained by the geological burial history of Cretaceous Qingshuihe Formation in the southern margin of Junggar Basin, the diagenetic physical simulation experiment was carried out with the low-mature sandstone samples taken from the outcrop area. Then, coupling with the regional geological data, the reformation of reservoirs with different diagenetic intensities by microfractures and the significance of microfractures for development of high-quality reservoirs were discussed. The results show that the large-scale microfractures were formed in the stage of late rapid deep burial, roughly equivalent to the period when organic acids were filled. The microfractures created good conditions for migration of oil and gas in deep and ultra-deep clastic rocks, and also enabled the transport of organic acids to the reservoirs for ensuing the late continuous dissolution of cements and particles. The existence of matrix pores and microfractures in the reservoirs before the rapid deep burial determined how the microfractures formed during rapid deep burial improved the reservoir quality. If matrix pores and microfractures were more developed and the cementation degree was lower before the rapid deep burial, the microfractures would be more developed and the dissolution degree would be higher during the late rapid deep burial, and so the reservoir quality would be improved more greatly, which can increase the reservoir permeability by up to 55%. If cementation was very strong, but matrix pores were not developed and microfractures existed locally before the rapid deep burial, the microfractures would also be more developed during the late rapid deep burial, which can increase the reservoir permeability by 43%. If cementation was strong, matrix pores were absent, and microfractures were not developed, limited microfractures would be formed during the late rapid deep burial, which can increase the reservoir permeability by only 16%. Formation of large-scale microfractures during late rapid deep burial and promotion of such mic

关 键 词：rapid deep burial MICROFRACTURE physical simulation deep reservoir Cretaceous Qingshuihe Formation Junggar Basin 

分 类 号：P618.13[天文地球—矿床学]