摘要
新发现的天津空港埋藏牡蛎礁体和下伏、上覆泥层的沉积学、AMS14C年代学研究显示,厚2.3m的礁体分为3部分,起讫年龄是6170～3980cal BP。5900～4100cal BP的中部,是受全新世冷事件4环境恶化控制的缓慢发育期。礁体的结束,则与冷事件3在时间上大致吻合。根据新的年龄数据,将该礁体的归属重新厘定为Ⅲ-2礁群。探讨礁体主要发育区与新构造活动的关系,表明全新世牡蛎礁平原主要位于海河-宝坻-工部-蓟运河断裂圈闭的北西-南东向区域内。这一认识,进一步从实证角度证实了牡蛎礁形成于渤海湾"湾中之湾"的推测。
The buried Konggang oyster reef,located in the northwestern coast of Bohai Bay,is a newly observed reef.Systematical sampling was carried out in the reef body and the underlying and overlying muddy sediments,respectively.AMS 14C dating shows that the duration of this reef is about 2200a from 6170 to 3980cal BP.The reef,2.3 m thick,can be divided into three parts.Its middle part,5900-4100cal BP,is a slowly-developed stagnant period coinciding with Cold Event 4.The end of the reef development was approximately consistent with Cold event 3.According to the new AMS 14C data,the reef has been reassigned to oyster reef Group III-2.Based on scrutinizing the relationship between the oyster reef development and the neotectonic movement,the authors hold that the Holocene oyster reef plain is mainly constrained by the alignment of Haihe-Baodi-Gongbu-Jiyunhe faults.This recognition has further proved the presumption that the oyster reefs were spatially distributed mainly in the so-called ＂Inner Bay＂ of the Bohai Bay.
出处
《地质通报》
CAS
CSCD
北大核心
2012年第9期1387-1393,共7页
Geological Bulletin of China
基金
国家自然科学基金面上项目<渤海湾西北岸埋藏牡蛎礁古环境重建>(批准号:40872106)
中国地质调查局项目<中国泥质海岸带对全球变化响应的研究与趋势预测>(编号:1212010911069)
天津古海岸与湿地国家级自然保护区处项目<贝壳堤
牡蛎礁新发现与新问题研究>
关键词
埋藏牡蛎礁
年代测定
环境恶化
新构造运动
buried oyster reef； age dating； environmental deterioration； neotectonic movement
