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郯庐断裂带的区域重力场呈现宽度较大的线性梯度带特征，在郯城与嘉山间有明显的扭曲。其东侧以正异常为背景，走向北东；西侧以近东西向异常为主，幅度变化较小。该区东侧是磁力低异常区；西侧是正异常区，正异常呈串珠状北北东向分布，可达50OnT。该区深部地震及大地电磁资料显示，具有岩石圈减薄、地幔上涌的特征。郯庐断裂带可分三段，南段是单支，中段是中生代两堑夹一垒的复式地堑，北段是新生代复式半地堑。该断裂从早三叠世至早侏罗世处于统一应力场下且具左行滑移特点，中侏罗世开始各段发育历史各异，晚第三纪又统一于扭压应力场下，并有右旋特征。由于该断裂陡直向深部延伸至地幔岩石圈，成为岩浆的通道，从而提高了渤海湾盆地东部各拗陷的生油岩充分转化成油气的能力，同时有利于深部烃类向上运移并聚集。这是渤海湾盆地东部油气比西部丰富的主要原因。由于郯庐断裂的作用，沂沐裂谷区也是油气勘操的远景区。
The regional gravitational field in the Tan-Lu fault zone shows the characteristics of a linear gradient with a large width, with obvious distortion between Tancheng and Jiashan. On the eastern side, with the positive anomaly as the background, it goes to the north east; the west is characterized by the near east-west anomaly, and its amplitude changes little. The area east of the area is a low magnetic anomaly area; the west is a positive anomaly area, positive anomaly bead north-east distribution, up to 50OnT. The deep earthquakes in the area and the electromagnetic data of the earth show the characteristics of lithospheric thinning and upwelling of the mantle. Tan-Lu fault zone can be divided into three sections, the southern section is a single, the middle section is a double-graben Mesozoic double graben, the northern section of the Cenozoic double half-graben. The fault from the Early Triassic to the Early Jurassic in a unified stress field and a left-slip characteristics of the Middle Jurassic beginning of the development of different segments of history, the late Tertiary and unified in the torsional stress field, And dextral features. Because the fault extends steeply deep into the mantle lithosphere and becomes the passage of magma, it improves the ability of the source rocks of various depressions in the east of Bohai Bay Basin to fully transform into oil and gas, and facilitates the upward migration and accumulation of deep hydrocarbons . This is the main reason why oil and gas in the eastern Bohai Bay Basin is more abundant than the west. Due to the role of Tan-Lu fault, Yi Mu Rift Valley is also a prospective area for oil and gas exploration.