K-Ar dating of synkinematic illite is increasingly recognized as a central method to constrain the timing of shallow crustal faulting. Methods of efficient sample preparation and quantitative identification of illite polytypes are critical to acquiring K-Ar isotope data for authigenic clays. In this respect, we compared the commonly used clay size separation method through centrifugation with vacuum filtration technology, showing that the former is prone to extract fractions with finer particle ... 相似文献
The landslide hazard is one of the geological hazards in mountainous zone.
Its occurrence is controlled by many factors. To assess the risk level of landslide in Shiwangmiao accurately, intuitionistic fuzzy sets-Topsis model is introduced at first; secondly, the decisive matrix about the intuitionistic fuzzy sets is established, and the index weight coefficients considering the uncertainty of assessment indices are determined by using the Entropy weight method, then the weighed decisive matrix is obtained. Finally, degree of membership at different levels about the landslide is determined based on the ranking sequence of degree of membership, the risk level corresponding to the maximum degree of membership is final assessment level. The conclusions are drawn that accurate rate of risk estimation about landslide hazards is very high based on the intuitionistic fuzzy sets model in comparison with the current specifications, and the method is feasible for the risk assessment of landslide hazards,
so it provides a new method and thoughts to assess the risk level of landslide in future.
Geotechnical and Geological Engineering - The debris flow hazards endanger the life and property safety of the people, so the investigation about the risk level assessment of debris flow has great... 相似文献
<正>The Yushu-Yidun arc magmatic belt has attracted much attention among geologists due to its complete record of the evolutionary process of the Sanjiang tectonic belt in eastern Tethys and its favorable metallogenic conditions.This belt is composed of the Late Triassic volcanicsedimentary rock series,and the Indosinian and Yanshanian granite intrusions.It has long been believed that there are no Jurassic or Cretaceous strata in this area. 相似文献
