摘要
系统收集并重新处理了华北克拉通中东部的重磁资料,利用处理结果,结合近年来华北克拉通前寒武纪结晶基底构造研究的进展,重新将华北克拉通中东部划分为2个一级重磁异常单元和7个二级重磁异常单元;重点描述了7条分划性断裂的重磁特征,特别指出中国东部重力梯度带正是华北克拉通中部'带的集中表现,而郯庐断裂带和兰考—聊城—盐山—台安—大洼断裂带是燕山期陆内不同刚性块体调整的重要边界,所以也是重磁特征的变异带.据此,对华北克拉通断裂与构造单元的重磁异常特征赋予了新的地质意义.研究表明,华北克拉通现今的地球物理特征能够反映结晶基底构造,其原因是华北克拉通现今构造格局是中新生代构造继承结晶基底构造的结果.
The gavity and magnetic data in the central and eastern North China Craton were collected and re-processed synthetically in this paper. The new-processed results were used to divide the geophysical anomaly units in the North China Craton, combined with its recent Precambrian tectonics research, into two first-order and seven second-order gravity-magnetic anomaly units. Seven border faults of second units in the North China Craton are also described by their gravity and magnetic anomalies. Especially a gavity gradient belt across the eastern China is equivalent to Precambrian Trans-North China Craton Orogen Belt in the North China Craton. However, the Tanlu and the Lankao-Liaocheng-Yanshan-Taian-Dawa faults are not only two important Yanshanian border faults, but also gravity and magnetic anomaly borders between different blocks of the North China Craton. According to these results, we give the linear and regional gravity and magnetic anomalies some new geological interpretations in this paper. This research shows that the current geophysical anomalies in the North China Craton can reflect its tectonic divisions of Precambrian crystalline basement because the current tectonic outline of the North China Craton are derived from Meso-Neozoic tectonic heritage to ancient crystalline basement.
出处
《地球物理学进展》
CSCD
2004年第1期91-100,共10页
Progress in Geophysics
基金
国家自然科学基金(40002015)
国家973项目(19990433)
中国科学院知识创新工程项目(KZCX1-07)联合资助.
关键词
华北板块
基底
构造
重力
磁力
the North China Craton, Basement, tectonics, gravity, magnet
