Laser ablation in situ U-Pb dating and its application to diagenesis-porosity evolution of carbonate reservoirs

论文摘要

Through the development and calibration of a reference material which is 209.8 Ma old using a newly-developed Laser Ablation（LA） Multi-Collector Inductively Coupled Plasma Mass Spectrometry（MC-ICP-MS） technique, we successfully overcome the difficulty in sampling and dating ultra-low U-Pb ancient marine carbonates, which was previously untenable by isotope dilution（ID） methods. We developed the LA-MC-ICP-MS in situ U-Pb dating technique for ancient marine carbonates for the study of diagenesis-porosity evolution history in Sinian Dengying Formation, Sichuan Basin. By systematically dating of dolomitic cements from vugs, matrix pores and fractures, we found that the burial and diagenetic process of dolomite reservoirs in Sinian Dengying Formation was characterized by progressive filling-up of primary pores and epigenic dissolution vugs. The filling of vugs happened in three stages, early Caledonian, late Hercynian-Indosinian and Yanshanian-Himalayan, while the filling of matrix pores mainly took place in early Caledonian. The unfilled residual vugs, pores and fractures constitute the main reservoir sapce. Based on the above knowledge, we established the diagenesis-porosity evolution history of the dolomite reservoir in Sinian Dengying Formation, Sichuan Basin. These findings are highly consistent with the tectonic-burial and basin thermal histories of the study area. Our study confirmed the reliability of this in situ U-Pb dating technique, which provides an effective way for the investigation of diagenesis-porosity evolution history and evaluation of porosity in ancient marine carbonate reservoirs before hydrocarbon migration.

论文目录

• Introduction
• 1. Geological background and sample description
•   1.1. Regional geological background
•   1.2. Sample characteristics and occurrences
• 2. Analysis method
•   2.1. U-Pb dating method and reference material for carbonate minerals
•   2.2. Preparation,testing and data processing of unknown samples
• 3. Case study
• 4. Discussions
•   4.1. Absolute ages of surrounding rocks and vug,pore and fracture fillings
•   4.2. Reconstruction and application of diagenesis-porosity evolution history
• 5. Conclusions

文章来源

类型: 期刊论文

作者: SHEN Anjiang,HU Anping,CHENG Ting,LIANG Feng,PAN Wenqing,FENG Yuexing,ZHAO Jianxin

来源: Petroleum Exploration and Development 2019年06期

年度: 2019

分类: 工程科技Ⅰ辑,基础科学

专业: 地质学,石油天然气工业

单位: Key Laboratory of Carbonate reservoirs, CNPC,PetroChina Hangzhou Research Institute of Geology (HIPG),Radiogenic Isotope Facility, School of Earth and Environmental Sciences, The University of Queensland,Beijing SHRIMP Center, Institute of Geology, Chinese Academy of Geological Sciences (CAGS),Research Institute of Exploration and Development, PetroChina Tarim Oilfield

基金: Suppored by the China National Science and Technology Major Project(2016ZX05004-002)

分类号: P618.13

页码: 1127-1140

总页数: 14

文件大小: 827K

下载量: 7