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贝内文托地区是亚平宁孕震带的一部分。该带在历史上和现代都曾经历过大的破坏性地震事件。研究地区位于伊尔皮尼亚断层的北端。该断层在1980年伴随着造成大约3000人伤亡的M_s=6.9正断层地震产生了破裂。本文旨在了解贝内文托地区上地壳的横向非均匀性并试图确定可能发生大地震的断裂段。这一工作受到识别那些由速度异常推断的大断层的岩石非均匀性可反映断裂块存在的启发。这些断裂块在大的破裂间隙中表现不同。本文中,我们利用由地方地震台阵于1991年和1992年记录的背景地震活动来确定贝内文托地区的地壳结构。这些资料提供了一个研究在几次大地震发生之前大的孕震层的构造间断性存在的很好的机会。我们已获得的主要成果是得到了在马泰塞石灰岩地块下边上地壳中两个NW走向的高速层的轮廓。这些高速层被解释成在至少2km深度处向下延伸30～40km的高强度区。这些高速层与历史地震(1688年,1805年)的最大烈度区的对应性表明,这些异常描述了有可能产生M=6.5～7.0的地震的南亚平宁地震带中两个断裂段的范围,根据层析成象结果得出的两个地段与等震区之间的横向偏离可能与横向右旋断层有关。
The Benevento area is part of the Apennine Seismic Belt. The band has experienced devastating earthquake events both in history and in the modern era. The study area is located at the northern end of the Ilpinian fault. The fault ruptured in 1980 with an M_s = 6.9 normal-fault earthquake that killed approximately 3,000 people. The purpose of this paper is to understand the lateral inhomogeneities of the upper crust in the Bayevento region and to try to identify the fault segments where a large earthquake may occur. This work is inspired by the identification of rock inhomogeneities of large faults that are extrapolated from velocity anomalies that can reflect the presence of fault blocks. These fracture blocks behave differently in large fracture gaps. In this paper, we use the background seismic activity recorded by local seismic units in 1991 and 1992 to determine the crustal structure in the Benevento area. These data provide a good opportunity to study the discontinuity of the structure of the large seismogenic layer before several major earthquakes occur. The main result we have obtained is the contour of the two NW-trending high-velocity layers in the crust below the Mateai limestone block. These high-velocity layers are interpreted as high-intensity zones that extend down 30 to 40 km at depths of at least 2 km. The correspondence of these high-velocity layers with the maximum intensity regions of historical earthquakes (1688, 1805) shows that these anomalies describe the extent of two fault segments in the South Apennine Seismic Belt that are likely to produce earthquakes of M = 6.5-7.0 according to The lateral deviations between the two locations and the isoseismic area as a result of tomographic imaging may be related to lateral dextral faults.