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961.
The paper presents the results of multidisciplinary seismic surveys carried out by refraction and reflection methods for compressional and shear waves on Yuzhno-Sakhalinsk mud volcano. A large extinct (approximately 60–70 years ago) volcano was identified near the active volcano, and its structure was studied. It was found that the recognized intermediate fluid-bearing chambers correlate with the distinguished tectonic dislocations. A supposition was made that the mud volcanism is sequentially developed in the northeastern direction and related to the modern tectonics of the Central Sakhalin Fault. 相似文献
962.
963.
多源地学数据包括遥感、地球化学和地球物理数据,介绍了利用多源地学数据进行造山带构造单元划分的方法。遥感数据在确定区域构造边界及活动断层方面的应用非常广泛,遥感影像在解译线形构造即断层方面有非常明显的效果,可以根据不同构造单元的影像差异,区分不同的地质体、线性构造及活动断层,同时用遥感数据叠加三维地形数据分析线性构造可以更加直观地解译线性构造。地球化学数据在确定大的构造边界方面具有一定的指示意义,可以根据水系沉积物的地球化学特点,运用因子分析方法确定大的构造边界。地球物理数据提供的是地质体及构造边界在深部的延伸情况,可以为研究断裂的运动学和动力学特征提供证据。 相似文献
964.
2007年5月由中国地质调查局主管部门建议.选定内蒙古达来庙地区的矿产远景调查项目作为矿产远景调查数据库系统应用的试点项目,全面开展了矿调数据库的建设。根据矿调工作的特点.项目利用数字地质调查系统完成了①地质填图野外数据PRB库;②实际材料图数据库;③地质矿产图空间数据库;④地球化学数据库;⑤地球物理数据库;⑥遥感数据库;⑦综合成果数据库和⑧大比例尺综合图数据库的建设,从而实现了将矿调工作原始资料、成果资料集于数字地质调查系统同一平台下的全部数字化。 相似文献
965.
966.
Vladimir Frid Gady Liskevich Dmitriy Doudkinski Nikolay Korostishevsky 《Environmental Geology》2008,53(7):1503-1508
This paper deals with an employment of electrical resistivity imaging (ERI) for survey of leachate content on the waste disposal
site in Northern Israel. The research consisted of conducting ten ERI lines and drilling investigation wells. Data simulation
used a 2D EarthImager inversion program. Analysis of 2D ERI interpretation results shows that determination of the boundary
between the landfill body bottom intensively saturated with leachates and underlying layers of highly water saturated fat
nonconsolidated clays presents a challenge. However, statistical analysis of ERI data indicates that standard deviation and
confidence interval of a set of resistivity data measured in the landfill body are significantly larger than those in underlying
clays. Moreover, maximum changes of these parameters are found on the boundary between landfill body and underlying soil,
thus reflecting natural differences in scattering of resistivity data measured in these two objects. 相似文献
967.
Salinity mapping of coastal groundwater aquifers using hydrogeochemical and geophysical methods: a case study from north Kelantan,Malaysia 总被引:2,自引:0,他引:2
Integrated hydrogeochemical and geophysical methods were used to study the salinity of groundwater aquifers along the coastal
area of north Kelantan. For the hydrogeochemical investigation, analysis of major ion contents of the groundwater was conducted,
and other chemical parameters such as pH and total dissolved solids were also determined. For the geophysical study, both
geoelectrical resistivity soundings and reflection seismic surveys were conducted to determine the characteristics of the
subsurface and groundwater contained within the aquifers. The pH values range from 6.2 to 6.8, indicating that the groundwater
in the study area is slightly acidic. Low content of chloride suggests that the groundwater in the first aquifer is fresh,
with an average concentration of about 15.8 mg/l and high geoelectrical resistivity (>45 ohm m). On the other hand, the groundwater
in the second aquifer is brackish, with chloride concentration ranging from 500 mg/l to 3,600 mg/l and very low geoelectrical
resistivity (<45 ohm m) as well as high concentration of total dissolved solids (>1,000 mg/l). The groundwater in the third
aquifer is fresh, with chloride concentrations generally ranging from 2 mg/l to 210 mg/l and geoelectrical resistivity of
greater than 45 ohm m. Fresh and saltwater interface in the first aquifer is generally located directly in the area of the
coast, but, for the second aquifer, both hydrogeochemical and geoelectrical resistivity results indicate that the fresh water
and saltwater interface is located as far as 6 km from the beach. The considerable chloride ion content initially suggests
that the salinity of the groundwater in the second aquifer is probably caused by the intrusion of seawater. However, continuous
monitoring of the chloride content of the second aquifer indicated no significant changes with time, from which it can be
inferred that the salinity of the groundwater is not affected by seasonal seawater intrusion. Schoeller diagrams illustrate
that sulphate concentrations of the groundwater of the second aquifer are relatively low compared to those of the recent seawater.
Therefore, this result suggests that the brackish water in the second aquifer is probably from ancient seawater that was trapped
within the sediments for a long period of time, rather than due to direct seawater intrusion. 相似文献
968.
在焦家金矿区地球化学测量的基础上,通过对不同矿化区段地球化学异常结构的因子分析,探讨矿致异常的元素组合特征.认为不同矿化区段公因子都为典型的热液矿床元素组合,其中成矿地段公因子变量数较少且相关性较大,公因子具有很强的代表性,而非矿化地段公因子中则变量相对较多,因子载荷较小;Co,Ni为典型的深源代表组分,仅在矿化地段表现为独立因子,且与主因子表现为明显的负相关;金元素在矿化地段各因子上均具有一定载荷,但集中分布在两个主因子上,而且与As,Hg,Ag,Pb元素的相关性较大,因此F1因子基本代表了矿化公因子的元素组合,是成矿预测最有效的指示标志. 相似文献
969.
970.
论述了新型高密度电阻率影象系统在地质构造勘测中的应用,并通过实例阐述了该系统在隧道勘查中的应用效果。高密度电阻率影象法作为一种无损、快速的探测手段,应该在地质构造特别是隧道勘查中进行推广应用。 相似文献