摘要
上震旦统灯影组 2段和 3段是四川盆地主要天然气储层之一。在浅色白云岩地层中富含炭化的黑色非叠层石生态系兰细菌白云岩。它既可发育于沉积期和胶结作用期 ,也可发育于表生成岩作用期。沉积期发育的非叠层石生态系兰细菌白云岩呈纹层状产出或围绕颗粒的四周生长。这类兰细菌白云岩的单层厚度从 1mm到 >10 cm不等 ,其总厚度约占灯影组 2段和 3段的 1/ 10左右 ,有时也呈不连续的黑色小点发育于白色叠层石生态系兰细菌白云岩的叠层石、层纹石中。胶结作用期 ,二或三个世代亮晶胶结物交替发育“充填”孔隙。表生成岩作用期 ,黑色的兰细菌主要呈多世代的线状纹层与白色纤维状白云石组成多世代的间互纹层充填在岩溶溶洞、溶沟以及扩溶的裂隙中。非叠层石生态系兰细菌主要形态有球形、椭球形和棒形 ,偶有蘑菇形及其它形状。群体呈现为串珠状、草丛状、分叉树枝状和类似于火山喷发状等等。群体的古生态表现为向上生长、围绕颗粒向四周发散生长、粘结颗粒 ,或向原生粒间孔隙、次生溶洞、溶沟中心向心生长。对现代兰细菌的降解实验佐证所讨论的非叠层石生态系兰细菌是灯影组中烃源岩之一。
Dengying formations 2 and 3 members of upper-Sinian is one of major nature gas reservior in Sichuang basin. In light colour dolostone abound with carbonification blackly non-stromatolite ecologic system cyanobacteria dolostone. It's developed not also in depositional and cementational stage,but also in hypergene diagenetic stage.At the depositional stage, it occure in laminae or surounded the grain growth in all sides.The singel bed thickness of these cyanobacteria dolostones from 1 mm to over 10 cm. And total thickness occupy about 10 percent in 2 and 3 members of Denging formation. Sometimes it show up incontinual small blackly points developed in whitely stromatolite ecologic system cyanobacteria dolostones,suck as stromatalolates, oncolite and others.At the hypergene diagenetic stage,the blackly non-stromatolite ecologic system cyanobactria mainly occurred in many generations linely laminae interbeded with wihite coloure fiber texture dolostone laminae filling the karstic cavity and channel, even in enlargeie dissolived crack.The major sharps of non-stromatolite ecalogic system cyanobactria are sphere,ellipsod and cudgel,occasionally are mushroom,monkhat and others.The colongs presented sharp are string bead,grass cluster,croteh and like the valcanic eruption,etc. All of these sharps show palaeocology of upword groweh or toword the centre of karstic cavity and channel. Degradation in test of modern cyanobactria evidenced that non-stromatolite ecologic system cyanobacteria dolostones is one of hydrocarbon source rock in Dengying formation.
出处
《沉积学报》
CAS
CSCD
北大核心
2003年第1期96-105,共10页
Acta Sedimentologica Sinica
基金
西南石油学院油气藏地质及开发工程国家重点实验室资助项目(编号97PLN10)
