松辽盆地砂岩中成岩次生矿物特征

CHARACTERISTICS OF DIAGENETIC SECONDARY MINERALS IN THE SANDSTONE OF THE SONGLIAO BASIN

杨桂芳 卓胜广 滕玉洪 牛奔 鄂俊杰

YANG Gui-fang ZHUO Sheng-guang TENG Yu-hong NIU Ben E Jun-jie

大庆石油学院 秦皇岛分院, 河北秦 皇岛 066000 2. 中海石油有限公司 上海分公司, 上海 200030 3. 中国石油 冀东油田, 河北 唐山 063004

Qinhuangdao Branch, Daqing Petroleum College, Qinhuangdao, Hebei 066000, China 2. Shanghai Branch, CNOOC, Shanghai 200030, China 3. Jidong Oil field, CNPC, Tangshan, Hebei 063004, China

砂岩在成岩过程中,次生矿物多达20余种。次生石英、钠长石、方解石和浊沸石等的形成不同程度地影响了砂岩的储集物性。形成次生石英的SiO2主要来源于碎屑长石的溶解粘土矿物的转化。次生长石与长石的钠长石化过程有关,斜长石钠长石化始于成岩早期,而钾长石的钠长石化则需较高的成岩条件才能进行。次生方解石主要为成岩早期的无机CaCO3沉淀。浊沸石则是晚成岩阶段的稳定矿物,并与成岩晚期钠长石化有关。

During the diagenetic process of sandstone,secondary minerals were up to more than 20 kinds.The formation of secondary quartz,albitite,calcite and laumontite affected the storage physical properties of sandstone in different degrees.The SiO2 forming secondary quartz mainly came from the transformation of dissolved clay mineral in clastic feldspar.Secondary feldspar was related to the albitization process of feldspar,the albitization of plagioclase began at the early stage of diagenesis,and the albitization of K feldspar can only underway under higher diagenetic conditions.Secondary calcite was mainly inorganic CaCO3 deposit in the early stage of diagenesis.Laumontite was stable mineral in the late diagenetic stage,and was related to the albitization in the late stage of diagenesis.

https://doi.org/10.11781/sysydz200206517