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川西北地区绵竹汉旺青岩沟、观音崖以及安县雎水剖面三叠纪卡尼期马鞍塘组硅质海绵礁群生长于碳酸盐岩缓坡带,可划分为礁基、礁核、礁翼、礁间沉积等亚相,据内碎屑含量、化石埋葬学特征以及灰泥等基质比例厘定岩相和群落特征。礁灰岩主要为海绵格架岩和钙质微生物凝块岩,附礁生物类型包括有孔虫类、双壳类、棘皮类、介形类、腕足类、粗枝藻类、钙质海绵等。马鞍塘组海绵礁终结之后上覆黑色页岩沉积。晚三叠世卡尼期气候骤变在全球生物圈引发广泛的效应,海平面升降速率相对海绵礁的生长速率较大,加之构造活动频繁,大火山岩省集中爆发以及超级季风盛行,从而导致了硅质海绵礁灭绝。
The Siliceous sponge reefs of the Triassic Carney Period Ma’antang Formation in the Qingyan ditch, Guanyinya and Guanshuiya sections of Mianzhu in Muanzhu, northwestern Sichuan, were grown in the gentle slope zone of carbonate rocks and can be divided into reef base, reef core and reef wing , Reef sediments and other subfacies. The lithofacies and community characteristics were determined according to the content of debris, burial characteristics of fossils and the proportion of matrix such as plaster. The reef limestone is mainly sponge frame rock and calcareous microbial agglomerate. The reef biological types include foraminifera, bivalves, echinoderms, ostracods, brachiopods, rough algae and calcareous sponge. Ma’ansitang sponge reef after the overlying black shale deposition. The Late Triassic Kargari climate change triggered a wide range of effects in the global biosphere. The sea-level rise and fall rates were relatively higher than those of the sponge reefs. In addition, frequent tectonic activities, large volcanic provinces and large-scale outbreaks of super-monsoon events resulted in silicon Sponge reefs extinct.