塔中Ⅰ号坡折带上奥陶统成礁背景分析
- 收稿日期:
1900-01-01
- 修回日期:
1900-01-01
- 刊出日期:
2010-06-10
摘要: 自塔中Ⅰ号坡折带上奥陶统良里塔格组发现生物礁滩作为重要储集层后，有关礁的形态和规模一直存在较大的争议。本研究解析该地区礁的古生物组合、古生态结构和沉积环境，以此为基础系统论证生物礁的沉积序列。礁的建造方式可归属于珊瑚骨架礁丘、层孔虫—海绵骨架礁丘、海绵—层孔虫骨架礁丘以及管孔藻—层孔虫骨架礁丘几种生态类型，这些骨架礁丘无论从造礁生物多样性、生态组合特征以及造礁规模，皆不同于前时代的前寒武纪叠层石礁、寒武纪古杯礁、早奥陶世的灰泥丘和托盘海绵礁，而呈现出单个礁体厚度大、发育旋回多之特点，多期礁体的垂向叠加、横向迁移造成礁体叠置连片, 形成了呈条带状展布的大型生物礁群。
Analysis on the Upper Ordovician Reef Formation along the Tazhong Slopebreak
- Institute of Resources and Environment , Southwest Petroleum University, Chengdu610500
- Received Date:
1900-01-01
- Rev Recd Date:
1900-01-01
- Publish Date:
2010-06-10
Abstract: Since the reefs and banks were found as significant reservoirs from the Upper Ordovician Lianglitag Formation, Tazhong Slopebreak I, debate on the reef aspects of morphology, magnitude, etc. still exist. We analy the regional reef biotic components, community structures and sedimentary backgrounds, and furthermore, synthetically interpret the reef sedimentary successions. Reefs are classified as the catalogues of coralframework reef, stromatoporoidlithisid spongia framework reef, lithisid spongia stromatoporoid framework reef, algae stromatoporoid framework reef respectively based on their biotic differentiations. These reefs differ from the former cases such as the stromatolites of the Precambrian, archeaocyathus reefs of the Cambrian, Calathium reefs of the Early Ordovician as well as the carbonate mudmounds of the Early Ordovician ecologically and lithologically, marked by their higher biodiversity, more complex of the ecological characteristics and magnitude. The reefcomplexes are generally more than tens meters showing in the frillcores. Reefs and banks stack horizontally and vertically. Therefore, extensions of the reefs and banks enhance the widespreading of the reefcomplexes along the Slopebreak.
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