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通过对中国东部及邻近海域磁异常数据的化极和上延处理,全面分析了不同构造块体和区域深大断裂的磁异常特征和空间展布,并在此基础上,通过计算化极后的磁异常数据的径向平均振幅谱,反演计算出区域居里等温面的深度分布.研究发现磁异常的化极和上延处理有效地增强了区域构造带(大别造山带、郯庐断裂、钓鱼岛隆起等)的边界特征.计算得到的居里等温面深度在19.6～48.9km之间,平均深约31.7km,下扬子地区的苏北盆地和南黄海盆地的居里等温面明显较深,最深可达35km左右,而其周围区域的居里等温面深约25km,表明了下扬子地区的苏北盆地和南黄海盆地在构造演化以及基底岩性和结构上的独特性.从区域上看,沉积盆地(苏北盆地、南黄海盆地、东海陆架盆地)的居里等温面一般较深,而周围隆起区(钓鱼岛隆起、浙闽隆起)的居里等温面一般较浅.在火山活动区(琉球岛弧、济州岛周围)以及沿江绍断裂海域部分居里等温面隆升非常明显,表明来自深部强烈的岩浆或其他地热活动.
By analyzing the magnetic anomalies and the extension of the magnetic anomaly data in the eastern and adjacent areas of China, the magnetic anomalies and spatial distribution of the deep faults in different tectonic blocks and regions are comprehensively analyzed. Based on this, And the depth distribution of the Curie isothermal surface was calculated by inversion.The study shows that the anomaly and upwelling of the magnetic anomaly effectively enhance the regional tectonic belt (Dabie orogen, Tanlu Fault, Diaoyu island uplift, etc. The calculated Curie isothermal depth ranged from 19.6 to 48.9km with an average depth of 31.7km, and the Curie isothermal surface of the Subei basin and the South Yellow Sea basin in the Lower Yangtze region was significantly Deep and deepest up to about 35km, while the Curie isothermal surface of the surrounding area is about 25km deep, which indicates the tectonic evolution and underlying lithology and structural uniqueness of the Subei basin and the southern Yellow Sea basin in the Lower Yangtze region. The Curie isotherms in the sedimentary basins (North Jiangsu Basin, South Yellow Sea Basin and East China Sea Shelf Basin) are generally deep, while the Curie Isothermal Surfaces are generally shallow in the surrounding uplift areas (Diaoyu Island uplift and Zhejiang-Fujian uplift) Activity area( Ryukyu Island arc, around Jeju Island), and part of the Curie isothermal uplift along the Changjiang Shao-Shaohai seafloor, indicating strong magmatic or other geothermal activity from the deep.