Tectonic Characteristics of Su-Lu Segment of the Tan-Lu Fault Zone Derived from RS and Gravity Multi-source Information
利用遥感、重力多源信息研究郯-庐断裂带苏-鲁段构造特征

Tectonic characteristics of Su-Lu segment of the Tan-Lu fault zone were studied in this paper. The method of tectonic geomorphology was used to study tectonic activity and geomorphological features of Su-Lu segment in late Quaternary. Moho depths were inversed using the variable density model. Meanwhile, wavelet multi-scale analytical method was applied to separating gravity fields, and the approximate depth of the field source was calculated by using the power spectrum analytical method. Then inhomogeneous features of crust density along Su-Lu segment were analyzed, and deep tectonic characteristics were studied. Geomorphological features, such as offset streams, fault scarps and linear tectonics, are developed along Su-Lu segment. These phenomena indicate that the Tan-Lu fault zone experienced strong right-lateral strike-slip movement in Late Quaternary. According to the Bouguer gravity field features, Moho depths undulate greatly, and Su-Lu segment cuts through the lithosphere. The uplift of the Moho occurs obviously beneath Linshu and Sihong areas, and the upwelling of high density materials of the upper mantle and asthenosphere occurs along the fault. On the west side of the fault, Moho depths reach 35 km. Su-Lu segment intersects other NW-striking faults. Geological and geophysical characteristics are clear. The density structure displays inhomogenous features laterally along the fault. The Bouguer gravity anomalies produced by the upper crust are correlated with the surface geology and topographic features.