Diagenetic differences caused by the charging of natural gases with various compositions - a case study on the lower Zhuhai Formation clastic reservoirs in the WC-A sag, the Pearl River Mouth Basin
Diagenetic differences caused by the charging of natural gases with various compositions - a case study on the lower Zhuhai Formation clastic reservoirs in the WC-A sag, the Pearl River Mouth Basin
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不同成分天然气充注引起的成岩差异——以珠江口盆地WC-A凹陷珠海组下部碎屑岩储层为例
DOI：
10.1016/j.marpetgeo.2017.01.004
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发表时间：
2017-03
影响因子：
4.2
通讯作者：
Wei Duan
中科院分区：
文献类型：
--
作者：
Wei Duan
只有为数不多的对比研究探讨了油气运聚过程中不同组分天然气充注所造成的储层成岩差异。定量评价了珠江口盆地WC-A凹陷珠海组下段储层在不同组分天然气充注作用下的成岩变化。所采用的方法包括电子显微镜、扫描电子显微镜、阴极发光、X射线衍射、地层水化学成分分析、稳定同位素分析和流体包裹体测定。结果表明：（1）在大裂缝附近的珠海组下段储层中，富CO2热流体的后期充注促进了矿物的溶解，改变了储层的孔隙度、渗透率、流体pH值和K+、Na+、Mg 2+等离子的含量。这些变化又间接影响了储层中粘土矿物的含量、形态和分布。此外，石英的次生加大作用也得到加强。(2)富CO2热流体的充注导致了强烈的溶解作用，并产生了高含量的胶结物。溶解作用主要发生在流体活动强烈的半开放体系中。从而阻止了渗透率的大幅度下降，形成了中孔-中渗储层。远离大裂缝的储层主要是早期富烃流体充注的。溶蚀作用较弱，生成的胶结物有限。此外，在这种封闭的成岩系统中，溶解产物无法排出。储层渗透率急剧下降，形成低孔低渗储层。
Only a limited number of comparative studies have explored the diagenetic differences of reservoirs caused by the charging of natural gases with different compositions during the migration and accumulation of oil and gas. In this study, we quantitatively assessed the diagenetic variations of the lower Zhuhai Formation reservoirs in the WC-A sag, the Pearl River Mouth Basin, as a result of natural gas charging with different compositions. The employed methods included electron microscopy, scanning electron microscopy, cathode luminescence, X-ray diffraction, chemical composition analysis of formation water, stable isotope analysis, and fluid inclusion determination. The results indicated that: (1) in the lower Zhuhai Formation reservoir that are near the large fractures, the late-charging of CO2-rich thermal fluid promoted the dissolution of minerals, and changed the porosity, permeability, pH value of fluid, and the contents of ions such as K+, Na+, Mg2+ of the reservoirs. These changes, in turn, indirectly affected the content, form, and distribution of clay minerals in the reservoirs. In addition, the secondary enlargement of quartz was enhanced. (2) The charging of CO2-rich thermal fluid caused strong dissolution and produced high contents of cements. The dissolution mainly occurred in a half open system with strong fluid activity. Consequently, the significantly decreasing of permeability was hindered and middle porosity–middle permeability reservoirs were generated. The reservoirs that are far from the large fractures, however, were mainly early charged by the hydrocarbon-rich fluid. The dissolution was weak and the generated cements were limited. In addition, the dissolution products could not be discharged in such closed diagenetic systems. As a result, the permeability of the reservoir was declined sharply and resulted in low porosity–low permeability reservoirs.
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影响因子：
3.5
作者：
J. Ajdukiewicz;R. E. Larese
通讯作者：
J. Ajdukiewicz;R. E. Larese
珠江口盆地白云凹陷裂后断裂活动机制
影响因子：
3
作者：
Zhen Sun;Ziying Xu;Longtao Sun;Xiong Pang;Chengzhi Yan;Yuanping Li;Zhongxian Zhao;Zhangwen Wang;Cuimei Zhang
通讯作者：
Cuimei Zhang
影响因子：
2.7
作者：
P. J. Hawkins
通讯作者：
P. J. Hawkins
影响因子：
1.8
作者：
Dai Jin-xing
通讯作者：
Dai Jin-xing
影响因子：
4.2
作者：
Hang Jiang;X. Pang;Hesheng Shi;Qiuhua Yu;Z. Cao;R. Yu;Di Chen;Z. Long;F. Jiang
通讯作者：
Hang Jiang;X. Pang;Hesheng Shi;Qiuhua Yu;Z. Cao;R. Yu;Di Chen;Z. Long;F. Jiang