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101.
Daniela Di Bucci Bruno Massa Milly Tornaghi Agostino Zuppetta 《Journal of Geodynamics》2006,42(4-5):175-193
The reconstruction of the main structural features of the Southern Apennines (Italy), in correspondence with the focal volume of some strong earthquakes that have affected this chain, can be attempted by analysing reflection seismic lines and deep well logs in comparison with surface geology.For instance, the Calore Valley and its surroundings have been the object of intense hydrocarbon exploration, and a wealth of subsurface data is available. Moreover, this area was affected by the 1688 Sannio earthquake (macroseismic magnitude 7.1), and a new location has recently been proposed for the related causative fault system. The present work defines the structural setting of the Southern Apennine chain in correspondence with this new location, and compares it with similar cases along the Italian peninsula.The analysis was focussed on the reconstruction of deep tectonic units (formed by the buried Apulia carbonate platform succession), which generally correspond to the hypocentral depths of strong earthquakes along the axis of the Southern Apennines. The results show that the Apulia platform succession is affected by three main thrusts, locally accompanied by backthrusts. The top of this succession is relatively shallow: the maximum depth does not exceed 1.8 s TWT (i.e. about 3500 m b.s.l.), while minimum depths occur in correspondence with the ramp anticlines culminations, at 0.5 s TWT (i.e. at about 500 m b.s.l.). Moreover, data suggest that the underlying Paleozoic basement is possibly involved in thrusting.In a regional perspective, extensional seismogenic structures along the axis of the Southern Apennines seem to share some common characteristics. Indeed, they develop (i) in correspondence with an uplifted Paleozoic basement; (ii) at the rear of a set of thrusts that account for the shallow Apulia units; (iii) at the surface, in proximity to the leading edge of a surficial tectonic unit formed by the Apennine carbonate platform succession. The 1688 seismogenic fault system fits in with these common traits. In the light of this, we finally speculate that these common characteristics in the architecture of the chain could provide a key to the location of the major seismicity along the axis of the Southern Apennines and an interpretative model for the identification of possible areas of seismic gap in this part of the Italian peninsula. 相似文献
102.
103.
三维可视化技术在辅助传统地质方法工作的同时,将复杂地质体形态、地质构造情况以三维的形式表现出来,呈现较丰富的的视觉效果。首次把三维可视化技术应用于贵州晴隆锑矿田找矿,有较好效果。 相似文献
104.
核桃坪铅锌铜多金属矿的靶区选择、评价及矿床发现中,由浅入深的物化探工作,在8个综合物化探异常区都找到多金属硫化物矿体,金厂河矿区实现隐伏深部找矿的重大突破。并总结出了一套合理的找矿勘查技术。 相似文献
105.
106.
Hydrodynamic forces on a partly buried cylinder exposed to combined waves and current 总被引:1,自引:0,他引:1
The present study extends the investigations of the hydrodynamic forces on a cylinder, laid on, or partly buried in the bed. They were determined by measuring the pressure distribution on the cylinder surface in the case of steady current, waves and coexisting flow. The pressure distribution around the cylinder was measured by using pressure transducers, which were replaced in the cylinder. Force coefficients were obtained for the ranges of Re=0.8×104–1.5×104, for steady current, low KC numbers (KC<5) for wave alone case and, for current-to-wave velocity RATIO=0, 3, 6 and infinity (current) for coexisting flow. The forces were also determined for the various burial-depth-to-diameter ratios between 0 and 0.7 values of the cylinder. 相似文献
107.
利用二维非均匀介质地震波传播的伪谱和有限差分混合方法,通过数值计算,讨论了松软覆盖层对隐伏断层带围陷波特征的影响.在没有覆盖层的情况下,围陷波振幅和围岩上相比明显增加,持续时间变长.覆盖层造成围岩上地面运动振幅增大,围陷波的部分能量传播到覆盖层中,使得围陷波的能量变小.随着覆盖层厚度增加,围陷波的振幅越来越小,和围岩上... 相似文献
108.
摘要:寒武系为川东南地区油气勘探的主体层位,根据野外露头特征、岩心样本、录井记录、地震概况及测井资料,对寒武系地层的岩性结构剖面进行初步分析,对层序关键界面识别与划分的标志进行详细描述,将其划分为3个三级层序。根据区内层序地层纵横特征,建立了寒武系的层序地层格架,研究了层序格架中海平面变化与岩溶作用的关系,对风化壳特征及储层研究都有重要指导意义。 相似文献
109.
110.
中国岩溶作用产生的大气CO2碳汇的分区计算 总被引:10,自引:9,他引:1
根据中国岩溶碳汇计算的需要,将我国岩溶地区划分为南方岩溶区、北方岩溶区、青藏高原岩溶区和埋藏岩溶区4种类型区,各区的岩溶面积分别为56.48万km2、32.58万km2、55.60万km2和200.1万km2。各区岩溶水的径流模数和岩溶作用强度存在差异,南方岩溶区比其他区的岩溶作用强度明显大得多。以取得的调查监测和统计资料为依据,对4种类型区和中国的岩溶碳汇量进行了重新计算,南方岩溶区、北方岩溶区、青藏高原岩溶区和埋藏岩溶区岩溶碳汇量分别为1909.9万tCO2/a、600.5万tCO2/a、580.1万tCO2/a、608.6万tCO2/a,由此获得中国岩溶碳汇总量为3699.1万tCO2/a。该结果比前人的研究更全面地反映了当前我国岩溶地区碳水钙无机循环产生的大气CO2汇量。 相似文献