摘要
二连盆地下白垩统烃源岩中普遍发育一套粒度偏细的富凝灰质的复杂岩性段,包括(沉)凝灰岩、凝灰质泥岩及凝灰质砂岩。以阿南凹陷腾格尔组一段为研究对象,通过岩心、薄片、扫描电镜、阴极发光及X衍射矿物分析等手段,讨论凝灰岩及凝灰质岩储层的岩石学特征及成岩作用。研究区凝灰岩主要呈薄层状夹于厚层泥岩中,分布在深湖-半深湖亚相,储层物性较好,以脱玻化孔为主,局部见隐晶、微晶的长英质或白云石充填脱玻孔或粒间孔。沉凝灰岩和凝灰质泥岩主要分布于扇三角洲前缘席状砂远端和滨浅湖亚相,处于中成岩阶段A2亚期,以凝灰质蚀变作用为主,生成的黏土矿物易充填孔隙,导致储层物性较差,以微孔和构造微裂隙为主。凝灰质砂岩主要分布于扇三角洲前缘,处于中成岩阶段A1亚期,溶蚀作用强烈,导致储层物性较好,以长石和方解石胶结物溶孔为主。研究表明,阿南凹陷腾一段的有利储层主要为分布在半深湖-深湖亚相的凝灰岩及扇三角洲前缘的凝灰质砂岩。
The Lower Cretaceous source rocks in most Erlian Basin sags developed a set of tight rocks including tuff, tuffite, tuffaceous mud and sandstones. Here, in the first member of the Tenggeer Formation in the Lower Cretaceous of the Anan Sag, and taking tuffaceous rocks as research objects, the petrologic and diagenetic characteristics of mixed rocks were studied using core observation, microscopy, scanning electron microscopy （SEM）, cathode luminescence （CL） and X-ray diffraction techniques. The results show that the thin lithic tuff, developed in the semi-deep to deep lakes, exhibits strong devitrification with localized occurrences of microcrystalline feldspar, quartz and dolomite. In comparison, the tuffite and tuffaceous mudstone, developed in the sand sheet of fan-delta front and semi-deep to deep lakes, are mainly in the Az mesogenetic stage, characterized by dolomite cementation with strong devitrification in authigenic clay minerals. Its reservoir space is relatively small and composed primarily of developing micropores and structural micro-cracks. Lastly, the tuffaceous sandstone, developed in the sand sheet of fan-delta front, is mainly in the A1 mesogenetic stage and characterized by strong compaction and calcite cementation, followed by dolomite and siliceous cementation. Its reservoir space, containing less primary developing pores, is mainly made of dissolution pores formed by dissolved feldspar fragments and carbonate cements. The semi-deep to deep lacustrine tuff and fan-delta front tuffaceous sandstone, therefore, are the favorable reservoir zones in the Arian Sag.
作者
魏巍
朱筱敏
朱世发
孙书洋
吴健平
王名巍
吕思翰
WEI Wei1'2,ZHU Xiaomin1'2',ZHU Shifa1'2,SUN Shuyang1'2,WU Jianping1,WANG Mingwei3,Lu Sihan4(1. College of Geosciences, China University of Petroleum （ Beijing ）, Beijing 102249, China 2. State Key Laboratory of Petroleum Resource and Prospecting, China ）University of Petroleum （Beijing）, Beijing 102249, China 3. Research Institute of Petroleum Exploration and Development, PetroChina ）Huabei Oilfield Company, Renqiu 062550, China 4. Power Group, No. 3 Oil Production Plant, PetroChina Daqing Oilfield Company, Daqing 163000, Chin)
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2018年第2期147-158,共12页
Earth Science Frontiers
基金
国家自然科学基金项目(41272133)
关键词
凝灰岩
凝灰质岩
成岩作用
腾一段
阿南凹陷
二连盆地
tuff
tuffaceous rock
diagenesis
first member of Tenggeer Formation
Allan Sag
Erlian Basin
