AUTHOR=Hu Zhangming , Hu Mingyi , Xiong Xianyue , Zheng Lijun , Wu Nan , Guang Youhui , Hu Xiaoling , Huang Xin 

TITLE=Geochemical characteristics of the braided river reservoir in block 19 of the sulige gas field

JOURNAL=Frontiers in Energy Research

VOLUME=Volume 11 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2023.1219664

DOI=10.3389/fenrg.2023.1219664

ISSN=2296-598X

ABSTRACT= The research resultsshow that the reservoir lithology in the study area is mainly composed of quartz sandstone, lithic sandstone, and quartzy lithic sandstone, with a porosity of 3%-13% and a permeability of (0.05-0.7)×10 -3 m 2 . It is a low-porosity and low-permeability reservoir; through drilling samples, 32 rock thin-section samples were selected. The pore types of the block reservoir are mainly intragranular dissolved pores and intergranular dissolved pores, accounting for 82.9%. The difference in pore structureThe property is mainly reflected in the size and distribution of the throat, the distribution of physical properties is 6-10%, the gas saturation is 61%, the NMR effective porosity is 7.49%, the permeability is 4.08×10 2 μm 2 , and the physical properties are relatively good; the study area The average thickness of the single braided channel in the lower section of He 8 is 4.7m, the average width of the channel is 963m, and the composite channel is distributed in a potato shape, parallel to the direction of the main flow. The average length of the channel is 2147m; the average width is 844m; As the porosity increases, the efficiency of gas-driven water also increases, and there is a linear positive correlation between porosity and gas-driven water efficiency. With the increase of movable water saturation, the water-air ratio becomes larger, and water production is more serious. In low-amplitude structures and Under low-permeability background conditions, for reservoirs with good local pore structure and physical properties, the water remaining at the bottom of the reservoir or sand body is controlled by the accumulation conditions or the weak structural differentiation after accumulation; the gas and water produced simultaneously in the study area When it comes out, the water production is relatively large, the gas production is less than 2×10 4 m 3 /d, and the water production is more than 10m3/d, which are mainly distributed in the downdip part of the main channel structure or in the island lens-shaped permeable sand bodies trapped by the surrounding tight layers.The research results provide theoretical data support for the exploration and production of the Sulige Gas Field.