凤凰─茶陵地学断面重力异常机制分析

对凤凰─茶陵地学断面重力异常,根据爆炸地震测深资料,确定密度分层,用变密度水平梯形体构制剖面密度模型,计算理论重力异常和实测布格重力异常吻合较好。根据剖面密度模型,可以合理地解释布格重力异常。并将地壳划分为沉积盖层、变质岩层、麻粒岩层三层结构,分别计算三层的重力效应曲线及上地幔低密度体重力效应曲线。还计算了莫霍面起伏引起的重力异常曲线,分析了引起地壳重力异常的各种因素及特点。

AN ANALYSIS OF MECHANISM OF GRAVITY ANOMALIES ALONG THE FENGHUANG-CHALING GEOSCIENCE SECTION

According to exploration seismic sounding data,density stratification wag fixed forgravity anomalies along the Fenghuang-Chaling geoscieroe section.The section density model wasessablished with the help of variable density horizontal trapezoid body,ac th6 calculated theoretical anomalies are coincideal with the measured Bouguer gravity anomalies.The Bouguer gravity anomalies can be reasonably interpred on the basis of the section density model.The earth crust was divided also sedimentary cover, metamorphic layer aam gramlito layer,with the gravity effect curves of these three layers and the gravity effect curve of the upper mantle low densitybody calculated respectively.In addition,the gravity anomaly curve caused by MOho reliefwas calculated, and various factors aam characteristics that give rise to crustal gravity anomalieswere analysed.