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展示了越南红河断裂带 (RRFZ)的地壳结构、断裂与地震活动表现的主要特征 ,研究结果表明 :(1)红河断裂带的莫霍面的深度在 2 2～ 2 4km与 30～ 32km之间变动 ,倾向北西 ;与之相反 ,此处地壳的结晶面则倾向北东且其在红河新生代拗陷的中部的深度只有 8～ 9km。(2 )在现代 ,红河断裂带受来自北东方向的挤压影响 ,在此断裂带的北东部分明显有强烈的隆升和地震活动。(3)地震震中主要分布于 7～ 2 0km的深度 ,大多数在 10～ 16km的范围内。震中最小深度与最大震级之间的相关函数为lgHmin=0 .2 5Ms- 0 .30(4)红河断裂带的主要孕震断裂为Lo河 ,VinhNinh ,Chay河 ,红河 ,Fansipan及BinhLuc等断裂。在红河断裂带地区 ,最强的地震可达Mmax=5 .5～ 6 .0级 ,而最强烈的地震活动带在Chay河与红河一带地区。(5 )红河断裂带地区区域地震危险性最高的可能在LucYen -YenBai和VietTri-Hanoi地区。
The main characteristics of the crustal structure, fault and seismic activity of the Honghe fault zone (RRFZ) in Vietnam are shown. The results show that: (1) the depth of the Moho in the Honghe fault zone ranges from 2 to 24km and from 30 to 32km On the contrary, the crystalline surface of the crust here tends to the northeast and its depth in the middle of the Red River Cenozoic depression is only 8 ~ 9 km. (2) In modern times, the Honghe fault zone is affected by the compression from the northeast direction, and there is a clear uplift and seismic activity in the northeast part of this fault zone. (3) Earthquake epicenters are mainly distributed in the depth of 7 ~ 20km, most of them are in the range of 10 ~ 16km. The correlation function between the minimum depth of the epicenter and the maximum magnitude is lgHmin = 0.25Ms-0.30. (4) The main seismogenic faults of the Honghe fault zone are Lo, VinhNinh, Chay, Honghe, Fansipan and BinhLuc faults. In the Honghe fault zone, the strongest earthquakes up to Mmax = 5.5 ~ 6.0, and the strongest seismic belt in the Chay River and Honghe area. (5) The areas with the highest risk of earthquakes in Honghe fault zone may be in the areas of LucYen-YenBai and VietTri-Hanoi.