Synthetic Geochemical Identification of Oil or Water Layers in Low Permeability Reservoirs——A Case from Jishan Sandbody, Jiyang Depression
详细信息
- 责任者：Liu Junmin (Guangzhou Institute of Geochemistry ; CAS ; Guangzhou 510640 ; China) ; Peng Ping’an
- 刊名：Petroleum Exploration and Development
- 出版年：2007
- 卷期：34(3)
- 关键词：低渗透储集层 ; low permeability reservoirs ; 油水界面 ; oil-water interface ; 济阳坳陷 ; Jiyang Depression
- 页码：p.335-338, 363
- 图表：4 illus., 17 refs.
- 分类号：1003
- issnNo：ISSN1000-0747
- isbnNo：CN11-2360/TE
摘要
Taking the low permeability reservoirs in the Jishan sandbody of Huimin Sag, Jiyang Depression as examples, together with limited data of well tests, the geochemical evaluation method for the reservoirs has been proposed as follows: 1) rock-Eval provides hydrocarbon content information to determine sketchily oil layers, water layers and oil-water layers, and the marginal values of ST are 4.O0 mg/g and 2.00 mg/g respectively; 2) pyro-GC is used as a supplementary tool to identify water layers; and 3) either variation coefficient calculated from the Rock-Eval data or P/DBT parameter from the GCMS data is available to distinguish oil layers from oil-water layers. The variation coefficient values of oil-water layers are more than 0.3 and those of oil layers are less than 0.3. The P/DBT ratios of oil water layers are less than 12.5 and those of oil layers are more than 12.5. The pyrolitie parameter S1/S2 can be used to distinguish genuine and sham harrier beds and evaluate the connectivity of oil columns for reservoirs with fast phase change and many muddy thin beds.