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1986年10月-1987年5月，中国第三次南极考察暨首次环球科学考察的实测重力资料表明，太平洋型活动陆缘重力异常面貌复杂，空间异常变化剧烈，处于极度不均衡状态。用sixx／x法反演了莫氏面深度，利用水层和地壳引起的垂直引力之和与实测的空间异常之差反演了软流层顶界的深度。结果显示，在海沟及其洋侧冷的软流层发生了大规模的沉降，而弧后热的软流层则强烈抬升。在弧沟间隙两侧，软流层这种大规模的差异运动是造成太平洋型活动陆缘强烈构造活动及不均衡状态的主要原因。而大西洋型被动陆缘，以单调的正、负不对称重力异常为主，“地壳的边界效应”在这里表现的较为明显；它缺少大规模的软流层升降运动和其它强烈的构造活动，且已达到均衡状态。
From October 1986 to May 1987, the measured gravimetric data from the Third Antarctic Expedition and the First Global Scientific Expedition in China show that the geomagnetic anomalies in the Pacific Ocean are complex and the spatial anomalies change violently and are in an extremely unbalanced state. The depth of Mohsian surface was inverted by sixx / x method. The difference between the sum of the vertical gravitation induced by water layer and crust and the measured spatial anomalies was used to invert the depth of the top of the asthenosphere. Results show that large-scale subsidence of the cold asthenosphere in the trenches and its oceanic side has occurred, while that of the back-arc heat strongly rises. On both sides of the arc gap, the large-scale differential movement of the asthenosphere is the main reason for the intense tectonic activity and imbalance in the Pacific margin. However, the Atlantic passive passive margin is dominated by monotonous positive and negative asymmetric gravity anomalies. “The crustal boundary effect” is more obvious here; it lacks large-scale hydrodynamic lift and other intense tectonic activities, And has reached equilibrium.