渤海海域渐新统古地磁年代地层柱的建立及其地质意义

A paleomagnetic column of Oligocene chronostratigraphy and its geological significance in Bohai water

渤海海域渐新统顶、底界线及内部地层单元没有实测地质年龄,对其地质年龄的确定只能参考国际年表。利用古地磁测年法确定了渤海海域渐新统地质年龄,建立了与国际古地磁标准年代表的对应关系,首次获得了最完整的渤海海域渐新统古地磁年代地层柱。在此基础之上,开展了渤海海域渐新统沉积速率计算、湖平面变化曲线校正和地层埋藏史分析,从而为该区油气勘探研究提供了新的地质依据。

In Bohai water, the geological ages of O ligocene top, base and its internal units can only be referred to some global geochronologic charts for their lack of the measured data. Therefore, palaeo magnetic dating was used to determine these geo logical ages, and their correlation with Global Palaomagnetic Time Scale was established, resul-ring in the most complete paleomagnetic column of Oligocene ehronostratigraphy in Bohai water for the first time. Based on this paleomagnetic col umn, some important works can be done in Bohai water, including calculating the Oligocene sedi- mentation rate, calibrating the curves of lake-level change and analyzing the burial history, which will provide new geological evidences for hydrocarbon exploration in Bohai water.