CAJ | 학술논문

鄂西峡口地区在构造上属中扬子台地北缘,发育了一套比较完整的中、上二叠统海相碳酸盐岩沉积.采用微相分析的方法,对中二叠统栖霞组碳酸盐岩的生物组合、微相类型和沉积环境进行了研究,将峡口地区的栖霞组沉积归纳为7种微相:多类型生物碎屑粒泥灰岩、含大壳体有孔虫的生物碎屑粒泥-泥粒灰岩、粗枝藻粒泥-泥粒灰岩、破碎的生物碎屑粒泥灰岩、具定向排列的藻屑-腕足泥粒灰岩、含内碎屑的生物碎屑泥粒灰岩、含原地珊瑚和藻类的生物碎屑泥粒灰岩.碳酸盐岩微相类型的垂向序列指示了峡口地区的栖霞组形成于碳酸盐岩缓坡环境,其底部地层沉积于内缓坡局限海相,中上部地层为内缓坡边缘低能生物丘相与内缓坡开阔海相的交替沉积.
악서협구지구재구조상속중양자태지북연,발육료일투비교완정적중、상이첩통해상탄산염암침적.채용미상분석적방법,대중이첩통서하조탄산염암적생물조합、미상류형화침적배경진행료연구,장협구지구적서하조침적귀납위7충미상:다류형생물쇄설립니회암、함대각체유공충적생물쇄설립니-니립회암、조지조립니-니립회암、파쇄적생물쇄설립니회암、구정향배렬적조설-완족니립회암、함내쇄설적생물쇄설니립회암、함원지산호화조류적생물쇄설니립회암.탄산염암미상류형적수향서렬지시료협구지구적서하조형성우탄산염암완파배경,기저부지층침적우내완파국한해상,중상부지층위내완파변연저능생물구상여내완파개활해상적교체침적.
Xiakou area is located on the north margin of the middle Yangtze platform, where successive middle to upper Permian marine carbonate strata were deposited. By means of carbonate microfacies, this paper conducted analysis on the biotic assemblages, microfacies types and sedimentary environments of the Chihsia Formation in this area. In total, seven types of microfacies were recognized: wackestone with diverse bioclasts, biotic wackestone-packstone with large foraminifers, biotic wackestone-packstone with dasycladacean, wackestone with fragmented bioclasts, biotic packstone with concordant algae and brachiopod shells, biotic packstone with intraclasts, biotic packstone with in-situ corals and algae. The vertical variation of these microfacies indicates that strata of the Chihsia Formation in Xiakou area were mainly deposited in a carbonate ramp environment. The lower part of the formation was deposited in a restricted marine environment of inner ramp, whereas the middle and upper part were formed alternatively in a mud mound environment at the edge of the inner ramp and an open marine environment of the inner ramp.