本文利用遥感与重力多源信息对郯庐断裂带苏鲁段构造特征进行了研究.应用构造地貌学方法分析了断裂带晚第四纪构造活动及地貌特征;基于Parker界面反演法,利用变密度模型计算了莫霍面深度;随后采用小波多尺度分析方法对局部重力场进行分离,进而分析研究了苏鲁段地壳密度非均匀性及深部地壳结构.沿苏鲁段断裂带发育的水系错断、断层陡坎、地层错断、线性构造等构造地貌特征,表明了断裂带在晚第四纪经历了明显的右旋逆冲走滑运动.通过对布格重力场的反演分析可知,郯庐断裂带苏鲁段底部莫霍面深度差异比较大,断裂带错断了莫霍面,在临沭及泗洪地区存在强烈的莫霍面隆起与沿断裂带的上地幔与软流层高密度物质上涌现像,西侧莫霍面深度最大达到35 km.苏鲁段断裂带被数条NW向断裂错断,在地表与深部都具有很明显的地质地貌与地球物理场特征.该区地壳介质密度具有显著的非均匀性特征,在中上地壳部位最明显,上地壳断裂带产生的布格重力异常与地表地形及地质地貌特征具有很大的相关性.%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 andtopographic features.
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