From deep basin gas to diagenetic trap—An example from the Yulin Gas Field in the Ordos Basin  

作　　者：ZHANG LiuPing LUO XiaoRong MA XinHua CHEN MengJin WU MingHui 

机构地区：[1]Key Laboratory of Petroleum Resource, Chinese Academy of Sciences, Beijing 100029, China [2]Research Institute of Petroleum Exploration and Development, PetroChina, Beijing 100083, China

出　　处：《Chinese Science Bulletin》2007年第21期2973-2983,共11页

基　　金：Supported by China National Basic Science "973" Project (Grant No. 2003CB214608);the Research Institute of Petroleum Exploration and Develop-ment, PetroChina

摘　　要：In the updip portion of the Yulin Gas Field in the Ordos Basin, there are no any structural, stratigraphic and sedimentary lithologic seals. Using thin-section petrography, ultraviolet fluorescence microscopy, micro-thermometry and Raman microspectrometry, this paper finds out the diagenetic trap and studies the diagenetic history of this field. It was revealed that three phases of diagenesis and hydrocarbon charging happened in late Triassic, late Jurassic and the end of early Cretaceous respectively. In the first two phases, acid geofluid entered the reservoir and caused dissolution and cementation. Although the porosities had been increased, further compaction accompanying re-subsidence resulted in tight sandstone and conglomerates. Till the end of the early Cretaceous, bulk of gas migrated into the tight reservoir. Cementation, however, kept on in the updip portion of this field due to low gas saturation and formed the diagenetic trap. The mechanism for gas accumulation was changed from deep basin gas to diagenetic trap, which offers a sealing condition that can retain gas for much longer time.In the updip portion of the Yulin Gas Field in the Ordos Basin, there are no any structural, straUgraphic and sedimentary lithologic seals. Using thin-section petrography, ultraviolet fluorescence microscopy, micro-thermometry and Raman microspectrometry, this paper finds out the diagenetic trap and studies the diagenetic history of this field. It was revealed that three phases of diagenesis and hydrocarbon charging happened in late Triassic, late Jurassic and the end of early Cretaceous respectively. In the first two phases, acid geofluid entered the reservoir and caused dissolution and cementation. Although the porosities had been increased, further compaction accompanying re-subsidence resulted in tight sandstone and conglomerates. Till the end of the early Cretaceous, bulk of gas migrated into the tight reservoir. Cementation, however, kept on in the updip portion of this field due to low gas saturation and formed the diagenetic trap. The mechanism for gas accumulation was changed from deep basin gas to diagenetic trap, which offers a sealing condition that can retain gas for much longer time.

关 键 词：天然气 气田 储气量 天然气开发 

分 类 号：F416.22[经济管理—产业经济]