火山岩储层微观孔隙结构分类评价——以准噶尔盆地东部西泉地区石炭系火山岩为例

Classification and evaluation of micro pore structure of volcanic rock reservoirs: A case study of the Carboniferous volcanic reservoirs in Xiquan area, eastern Junggar Basin

马尚伟 罗静兰 陈春勇 何贤英 代静静 许学龙 汪冲

Ma Shangwei Luo Jinglan Chen Chunyong He Xianying Dai Jingjing Xu Xuelong Wang Chong

大陆动力学国家重点实验室(西北大学), 西安 710069 2. 中国石油 新疆油田公司 准东采油厂, 新疆 阜康 831511

State Key Laboratory of Continental Dynamics, Northwest University, Xi'an, Shaanxi 710069, China 2. Zhundong Production Plant, Xinjiang Oilfield Company Ltd, PetroChina, Fukang, Xinjiang 831511, China

基于准噶尔盆地西泉地区火山岩储层特征研究较薄弱的现象，通过25口井的岩心观察、铸体薄片、扫描电镜及高压压汞等分析，以产能大小为依据，将火山岩储层分为4类，对火山岩储集空间类型及组合、微观孔隙结构特征进行分类评价。根据研究区火山岩储层面孔率及优势储集空间组合关系：Ⅰ类为气孔+溶蚀扩大孔、溶蚀孔+裂缝型，Ⅱ类为气孔+构造缝（溶蚀缝）型，Ⅲ类为气孔+溶孔型，Ⅳ类为孤立小孔隙型，面孔率依次降低。火山岩储层不同类型微观孔隙结构特征表明：Ⅰ类储层发育大孔隙、粗喉道，为优势储集层；Ⅱ类和Ⅲ类储层发育大—中孔隙，中—细喉道，为较好到中—差储层；Ⅳ类储层发育小孔隙、细喉道，为致密储层。在此基础上，结合测井资料，建立了研究区火山岩储层分类评价标准。

The studies of the characteristics of volcanic reservoirs in Xiquan area of the Junggar Basin are relatively weak. The pore types and pore assemblages as well as the micro pore structural features of the Carboniferous volcanic reservoirs in Xiquan area were classified and evaluated in this paper according to hydrocarbon yield, and also based on the observation and description of cores from 25 drilling wells, and the identification and quantifying of casting thin sections under microscope, measurement of SEM, porosity and permeability and capillary pressure. Four types of volcanic reservoirs were identified based on the thin-section porosity and the superior pore assemblage. The type Ⅰ pore assemblage is the vesicles+enlarged dissolution vesicles and dissolution pores+fractures. The type Ⅱ includes vesicles+structural fractures+dissolution fissures. The type Ⅲ is vesicles+dissolution pores, while only isolated fine pores developed in the type Ⅳ reservoir. The thin-section porosity reduces in turn from the type Ⅰ to the type Ⅳ. Different micropore structure of the volcanic reservoirs indicated that the type Ⅰ is an excellent reservoir with well-developed large pores and coarse throats. The type Ⅱ and type Ⅲ are better to medium favorable reservoirs with developed large to medium pores and medium to fine throats. While the type Ⅳ is a tight reservoir due to its fine pores and fine to micro throats. Finally, a volcanic reservoir classification and evaluation criterion for the study area was established on the basis of the above study and integrated with well logging data.

国家科技重大专项“东西部火山岩储层与鄂尔多斯盆地长7致密砂岩储层成岩演化序列与有利储层评价”（2011ZX05001-002-008）资助。

https://doi.org/10.11781/sysydz201705647