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根据大别山深地震测深剖面的资料， 取得了大别山地区的地壳结构模型． 二维地壳结构显示了碰撞造山带的特征和超高压变质带的深部地球物理证据． 地壳上部的三维速度结构表明： 在２ ｋｍ 深度上速度分布与地表的地质构造明显相关， 在５～１０ ｋｍ 深度上超高压变质带显示相对高速． 布格重力异常的观测资料显示大别山地区有较大范围的负异常． 在由上部地壳引起的布格重力异常中， 超高压变质带则为正异常区． 由于在地震剖面的二维地壳模型中， 造山带的山根仅有４～５ ｋｍ 厚， 且上地幔顶部的速度横向变化不明显， 因此可以认为，观测与计算的布格重力异常不一致的原因主要来自地壳， 至少在中上地壳内应产生负布格重力异常． 超高压变质带中地壳内的物质密度应比周围地区低． 这一较低密度的物质与扬子地壳向北俯冲到１００ ｋｍ 以下的深度， 然后返回地壳的碰撞过程有关．
According to the data of the deep seismic sounding profile of the Dabie Mountains, the crustal structure model of the Dabie Mountain area has been obtained. The 2D crustal structure shows the characteristics of the collision orogenic belt and the deep geophysical evidence of UHP metamorphic belt. The 3D velocity structure in the upper part of the crust shows that the velocity distribution is obviously related to the surface geological structure at a depth of 2 km, and the UHP metamorphic belt shows a relatively high velocity at a depth of 5 to 10 km. The observation data of the Bouguer gravity anomaly show that there are a large range of negative anomalies in the Dabie Mountains. In the Bouguer gravity anomaly caused by the upper crust, the UHP metamorphic zone is a positive anomalous zone. In the two-dimensional crustal model of the seismic section, the mountain roots of the orogenic belt are only 4 ~ 5 km thick and the lateral velocity variations at the top of the upper mantle are not obvious. Therefore, it is considered that the reason for the observed and calculated Bouguer gravity anomalies is mainly From the crust, at least in the middle and upper crust should produce negative Bouguer gravity anomalies. The density of matter in the crust in the UHP metamorphic belt should be lower than that in the surrounding area. This lower-density material is associated with the subduction of the Yangtze crust to a depth below 100 km and back to the crustal collision.