扬子地块A盆地晚古生代古地磁分析

The Late Paleozoic Paleomagnetic Analysis of A Basin in Yangtze Plate

扬子地块A盆地中生代以来沉积中心经历了弧形迁移,盆地是否发生旋转具有争议。根据古地磁数据计算古纬度表明,该盆地晚二叠世以来主要经历了大规模的北向漂移、南向漂移、快速北向漂移。现有精度古地磁数据分析表明,该盆地中生代以来,相对于欧亚大陆、扬子地块的旋转量都小于误差范围,缺乏有效意义的旋转。盆地中新生代沉积中心的弧形迁移反映了周缘造山带不同时期的构造活动对该盆地沉降及沉积的控制。

Since the Mesozoic,the sedimentary center of A Basin experienced an arc migration,a dispute appeared on if a rotation was induced in the basin.The calculation of palaeolatitude with paleomagnetic data indicated that since the Late Paleozoic,A Basin experienced large scale of drift from the south to north and quick to the north.The data of available accurate paleomagnetic analysis indicated that since the Mesozoic in the basin,the calculation of rotation amount that was relative to the Eurasian continent and Yangtze plate was less than the given error scope,there was no significative rotation.The arcuate migration in sedimentary center of A-Basin reflects the control of tectonic movement of the adjacent orogens from different periods on the subsidence and sediment in the basin.