冷家沙三段砂岩成岩序列与孔隙演化

Diagenetic sequences and porosity evolution in the sandstones of the Sha-3 Member of the Lengjia district, Liaohe Basin

笔者以辽河盆地冷家地区冷 94井为例 ,通过铸体薄片、电镜扫描、能谱分析和阴极发光等分析和实验手段 ,对沙三段砂岩的成岩历史、成岩序列与孔隙演化及发展趋势进行研究。指出成岩阶段可划分为同生期→早成岩阶段早期→早成岩阶段晚期→晚成岩阶段早期。孔隙演化主要在压实作用 ,粘土矿物的包膜作用 ,方解石、白云石的胶结作用 ,长石溶蚀作用 ,石英的次生加大和微晶石英的沉淀作用等方面进行了研究 ,阐述并总结了它们互相之间的内在联系。

Exemplified by the Leng 94 well in the Lengjia district, Liaohe Basin, the diagenetic history, diagenetic sequences and porosity evolution and trends are examined on the basis of thin section, SEMP, energy spectrum and cathodoluminescence examination. The diagenetic stages may be divided into: (1) syndiagenesis; (2) early stage of early diagenesis; (3) late stage of early diagenesis, and (4) early stage of late diagenesis. The porosity evolution has been explored here in the aspects such as compaction, coatings of clay minerals, cementation of calcite and dolomite, solution of feldspar, secondary overgrowth of quartz and precipitation of microcrystalline quartz.