对湖北基底构造的探讨

A DISCUSSION ON THE STRUCTURE OF BASEMENT IN HUBEI

以最新航磁编图数据和大量物性参数为依据,采用频率域正则化滤波分离磁性基底异常;磁性基底正反演采用parker公式,获得湖北及邻区前震旦系磁性界面等深图;利用最新重力资料,采用频率域正则化滤波分离莫霍面的布格异常;根据莫霍面等深图和磁性界面等深图,结合其它地球物理资料解释并推断湖北深部地质构造特征。推断结果认为:太古至早元古代构造层在秦岭地槽和扬子准地台均有见及,元古代构造层在湖北分布较广。扬于准地台北缘深部边界在西端和东端均有北移的可能,桐柏—大别隆起,具有独立块体的特征,其构造归属值得进一步研究。

According to the recent data of aeromagnetic compilation and a vast amount of para-meters of physical property, the anomalies of magnetic basement were determinated by canonical filtering of frequency domain. Using Parker formula in the direct and inversed of magnetic basement, we have completed the isobath-map of magnetic interfaces of Presinian in Hubei and its adjacent area. On the basis of recent data of gravity, the Bouguer anomalies of Moho discontinuity were divided by canonical filtering of frequency domain. According to the isobath-maps of Moho-discontinuity and magnetic interface combinated with other geophysical data, we have interpreted the features of deep-seated structure in Hubei below: The structural layer of Archaeozoic-Early Proterozic Era occurred in the both Qinling geocyncline and Yangtze paraplatform. The structural layer of Proterozoic Era distributed in Hubei Province extensively. The deep-seated boundary of North margin of the Yangtze paraplatform has probably displaced toward North at both its East and West ends. The Tongbaishan-Dabieshan uplift possesses the features of an independent mass, and further study of its structural attribution is necessary.