Effectiveness and Filling Characteristics of the Fractures of Cambrian Dolomite Reservoir in the Northern Tarim Basin, China(PDF)
《地球科学与环境学报》[ISSN:1672-6561/CN:61-1423/P]
- Issue:
- 2019年第01期
- Page:
- 40-53
- Research Field:
- 基础地质与矿产地质
- Publishing date:
Info
- Title:
- Effectiveness and Filling Characteristics of the Fractures of Cambrian Dolomite Reservoir in the Northern Tarim Basin, China
- Author(s):
- PENG Jun; LIN Pan; XIA Qing-song; LI Bin; HAN Hao-dong
- 1. School of Geoscience and Technology, Southwest Petroleum University, Chengdu 610500, Sichuan, China；2. Chengdu Center, China Geological Survey, Chengdu 610081, Sichuan, China
- Keywords:
- dolomite reservoir; effectiveness of fracture; filling characteristic of fracture; fluid inclusion; temperature; diagenetic fluid; Cambrian; Tarim Basin
- PACS:
- P618.13
- DOI:
- -
- Abstract:
- The Cambrian dolomite reservoir in Tarim Basin is characterized by old age, deep burial and strong diagenesis, whose primary porosity is almost completely destroyed，and the development of effective fracture is the key to the quality of reservoir. Research on the effectiveness and filling characteristics of the fractures of Cambrian dolomite reservoir in the northern Tarim Basin is based on the core and thin-sections, formation microscanner image (FMI) logging, scanning electron microscope (SEM), cathode luminescence microscope (CLM), electron microprobe and fluid inclusion methods. The results indicate that the fracture is growing in the northern Tarim Basin, in which the fractures in the southern Tianshan area and Tahe area are different in occurrence, linear density, shapes and the filling characteristics. In the southern Tianshan area, the linear density and effectiveness of fractures are lower than those in Tahe area, and the filling minerals are dominated by idiomorphic dolomite and quartz, followed by calcite, gypsum and pyrite. Dolomite-filling is divided into three stages and the corresponding temperature ranges are 70 ℃-90 ℃, 90 ℃-110 ℃ and more than 110 ℃, which are caused by diagenetic fluid in strata; the quartz-filling is divided into two phases, the first is caused by the clay minerals alteration, and the second may be the hydrothermal genesis. Tahe area, in which the linear density and effectiveness of fractures are well and the dissolution develops, is a favorable exploration zone; the filling minerals are made of hydrothermal minerals, which are dominated by calcite and followed by gypsum, saddle dolomite, clay mineral, asphalt, etc., and the barite occurs in the form of metasomatic dolomite. Calcite-filling is four times in Tahe area and the corresponding temperature ranges are 70 ℃-100 ℃, 100 ℃-130 ℃, 130 ℃-180 ℃ and more than 180 ℃, among the first three periods are the genesis of diagenetic fluid in different buried depth, and the last one is caused by high temperature hydrothermal fluid from the lower migration.
Last Update: 2019-01-25