华南泥盆纪微生物岩和生物礁发育的地质和古生物控制研究

The study will be focused on the microbialite and reefs during the Devonian important environmental and climate changes and major biotic events in South China. By means of geomicrobiologic, carbonate sedimentologic and sedimentary geochemical methods, the development and distribution of the microbialite and reefs and their relationships with other carbonate depositional bodies of the carbonate platform margin and other platform subfacies will be conducted. The effects and controls, from geological factors (e.g., climate, ocean chemistry, sea level change and habitat nutrient variation) and biological factors (predation feeding and competition, photosynthetic symbiotic and nutritional needs between metazoan and microbes, and biodiversity), on the development of the microbialite and reefs in different carbonate platform settings will be addressed. The relation between microbialite growth and biodiversity fluctuations and the relation between microbialite and reefal development will be deciphered. The nutritional gradient mode of microbialite and reefs, the dynamic response of sea level change, the physical and chemical indicators and the interactions and evolutionary adaptation of biologic factors during microbialite and reef thriving and decline will be established. Research results are of great theoretical and practical significance in research on microbial buildups, sequence stratigraphy, the motivation of extinction, paleoenvironmental and paleoclimatic changes, microbial mineralization, hydrocarbon reservoir, ancient cold seep carbonate deposition, and the recovery of the Holocene environmental and climatic changes.

选择华南泥盆纪重要环境和气候变化及重大生物事件时期的微生物岩和生物礁开展研究，通过地质微生物学、碳酸盐沉积学和沉积地球化学研究来确定微生物岩和生物礁在华南泥盆纪碳酸盐台地边缘和台内不同亚相中的发育、分布及与其他碳酸盐沉积体的关系；探讨地质因素（气候、海洋化学、海平面和栖息地养分变化等）和生物因素（后生生物与微生物之间的捕食、取食和竞争、光合共生和营养需求的关系及生物多样性等）对碳酸盐台地不同环境中微生物岩和生物礁发育的影响和控制；阐明微生物岩发育与生物多样性波动及微生物岩与生物礁发育的关系, 建立微生物岩和生物礁的营养梯度模式、海平面变化的动态响应、微生物岩和生物礁繁盛衰退的物理化学指标和生物学因素的相互作用及进化适应。研究成果对微生物岩建隆、层序地层、生物灭绝的动因、古环境和古气候变化、微生物矿化、油气成藏、古冷泉碳酸盐沉积和全新世环境气候变化的恢复等研究都具有重要的理论和实际意义。

课题对华南泥盆纪生物礁和微生物岩进行了大范围的调查和研究。沿着从陆架边缘、经台地向岸的考察路线，重点对广西德保钦甲泥盆纪早期埃姆斯期的点礁、融安泗顶泥盆系上统融县组中的微生物(核形石)灰岩、武宣二塘和象州大乐的泥盆纪生物礁碳酸盐台地沉积、南丹六寨的中晚泥盆纪滩相沉积、贵州独山布寨的中、晚泥盆纪生物礁以及紫云猫营的中、晚泥盆纪生物礁进行了野外详细剖面测量、横向追索、系统取样和综合分析和研究。通过地质微生物学、碳酸盐沉积学和沉积地球化学等研究方法调查和确定了微生物岩和生物礁在华南泥盆纪碳酸盐台地边缘和台内不同亚相中的发育、分布及与其他碳酸盐沉积体的关系; 初步认识了泥盆纪重要环境和气候变化及重大生物事件时期的微生物岩和生物礁的发育形式, 初步分析和探讨了地质因素（气候、海洋化学、海平面和栖息地养分变化等）和古生物因素（后生生物与微生物之间的捕食、取食和竞争、光合共生和营养需求的关系及生物多样性等）对碳酸盐台地不同环境中微生物岩和生物礁发育的影响和控制以及微生物岩发育与生物多样性波动及微生物岩与生物礁发育的关系。