We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Origin and formation mechanism of dolomite in Penglaiba Formation of Yonganba outcrop, Tarim Basin: Evidence from ordering degree and unit cell parameters.
- Authors
Ze-yu WANG; Zhan-feng QIAO; Fang-yi SHOU; Shao-xing MENG; Xue-ju LÜ
- Abstract
There are three types of dolomites in Penglaiba Formation of Yonganba outcrop in the Bachu area of the Tarim Basin. Based on the analysis of the sedimentary context of this area, and the characteristics of dolomite and XRD results, it could be suggested that three types of dolomites represent different sedimentary environments and process. The average ordering degree of powder crystal dolomite is 0.75 and their unit cell parameters deviate from that of ideal dolomite, which means they are the products of lime-muds by both rapid dolomitization in penecontemporaneous stage and recrystallization in shallow burial stage. The average ordering degree of the finemiddle crystal dolomite is 0.79 and their unit cell parameters are close to ideal dolomite, indicating the effects from porous grain limestones with both dolomitization in penecontemporaneous stage and adjustment to burial dolomites during the burial stage. The average ordering degree of coarse crystal dolomite is 0.90 whose unit cell parameters are close to the ideal dolomite, revealing their original rocks are granular limestones influenced by the persistent and sufficient dolomization fluids, with the slower crystallization speed and longer dolomization period. Preservation of pores and formation of effective reservoirs in the fine-middle crystal dolomites were more common than in other two types, because of the disequilibrium dolomitization.
- Subjects
UNIT cell; DOLOMITE; SEDIMENTATION &; deposition
- Publication
Natural Gas Geoscience, 2020, Vol 31, Issue 5, p602
- ISSN
1672-1926
- Publication type
Article
- DOI
10.11764/j.issn.1672-1926.2020.04.010