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81.
The Eastern Kunlun fault zone (EKLF) is a large left-lateral strike-slip fault, whose slip rate is meaningful to seismic hazard assessment and geodynamics of the Tibetan Plateau. Previous studies suggested that the late Quaternary average slip rate was stable and uniform (10~13 mm/a) in the central and western segment of the EKLF. But there were a few researches of accurate slip rate in the central segment on the EKLF. Therefore, we focused on an offset and well preserved alluvial fan from Xiugou basin, located in the east of Xidatan-Dongdatan, to make it clear. Moreover, we used high-resolution satellite images and digital elevation model extracted from SPOT7 stereo image pairs to restore the offset alluvial fan, and combined terrestrial cosmogenic nuclides method, including 13 quartz-rich samples from this fan surface, 1 quartz-rich sample from the main active channel bed and 1 10Be depth profile from this fan edge to eliminate the 10Be concentration of inheritance accurately, with 1 optically stimulated luminescence sample to obtain the reliable age of this alluvial fan together. Referring to field observations, this alluvial fan was offset left-laterally by (1 862±103) m, and its age is (76.55±3.20)~(106.37±3.38) ka which can be determined through the actual geologic setting and improving chi-square test. Thus, we used the Monte Carlo method to obtain a left-lateral slip rate of (20.3+3.5/-2.3) mm/a with 68% confidence envelopes since the late Pleistocene in the Xiugou basin. As a result, combining with the results of previous studies, the left-lateral slip rate indicated that the obviously decreasing activity transferred from late Pleistocene to Holocene on the central segment of the EKLF. 相似文献
82.
The aim of this paper is to propose a location model of earthquake emergency service depot on the basis of hybrid multi-attribute decision-making method. The advantage of the proposed method is that practical mixed uncertainty of location decision information is considered, and the corresponding factors that affect the location of transfer stations are contained. To solve the location problem, a hybrid multi-attribute decision procedure without information transformation is developed. Besides, a novel weighting method and aggregation process is given. Finally, a numerical example is provided to show the feasibility and validity of the proposed method. 相似文献
83.
Natural Hazards - It is common knowledge that drought is considered one of the most damaging natural disasters in terms of economic costs, societal problems, and ecological impacts. In this study,... 相似文献
84.
S. W. Mao J. M. Li W. Liu Z. C. Wang Z. L. Huang 《Australian Journal of Earth Sciences》2018,65(4):535-555
The Middle Ordovician Kelimoli Formation carbonate reservoirs in the northern Tianhuan area, Ordos Basin, China are main exploration targets. Subsurface core samples, logging, drilling and production data from the area were used to characterise the carbonate reservoir and to construct a genetic model for exploration. The sedimentary facies identified include trough–continental rise, upper–lower slope, platform margin reef-shoal, open platform and evaporation-restricted platform. The slope and platform margin facies are potential zones for high-quality reservoirs. Porosity in the study area comprises intergrain, intercrystal, intragrain and intracrystal pores, fractures and vughs. The Sr/Ba (0.40–4.87) and V/(V + Ni) (0.64–0.97) ratios indicate deposition in a brackish water-dominated environment under reducing conditions, associated with sea-level fluctuations during the deposition of the Kelimoli Formation. The Sr/Ba, V/(V + Ni), 87Sr/86Sr ratios, δ18O values and crystal texture of dolomite samples suggest that meteoric water was involved in the diagenetic fluid in the near-surface depositional environment. Isotopes (δ13C and δ18O) and trace elements (Fe and Mn) allowed the identification of seepage-reflux and mixed-water dolomitisation. The crystal textures of the samples consist of micritic, bioclastic and reefal limestones, and dolomite with gypsum, which were easily dissolved during the early diagenetic stage. The epidiagenetic stage was the key period for the development of high-quality reservoirs because of large-scale bedding-parallel karstification from meteoric water. The reservoir zones, dominated by partially filled and unfilled vughs, and fractures, are favourable exploration targets in the northern Tianhuan area. 相似文献
85.
The aim of this study is to establish a detailed and complete inventory of the landslides triggered by the Mj 7.3 (Mw 7.0) Kumamoto, Japan, earthquake sequence of 15 April 2016 (16 April in JST). Based on high-resolution (0.5–2 m) optical satellite images, we delineated 3,467 individual landslides triggered by the earthquake, occupying an area of about 6.9 km2. Then they were validated by aerial photographs with very high-resolution (better than 0.5 m) and oblique field photos. Of them, 3,460 landslides are distributed in an elliptical area about 6000 km2, with a NE-SW directed 120-km-long long axis and a 60-km-long NW-SE trending short axis. Most of the landslides are shallow, disrupted falls and slides, with a few flow-type slides and rock and soil avalanches. The analysis of correlation between the landslides and several control factors shows the areas of elevation 1000–1200 m, stratum of Q3-Hvf, seismic intensity VIII and VIII+, and peak ground acceleration (PGA) 0.4–0.6 g register the highest landslide abundance. This study also discussed the relationship between the spatial pattern of the landslides and the seismotectonic structure featured by a strike-slip fault with a normal component and the volcanism in the study area. 相似文献
86.
Plant drought tolerance trait is the key parameter in improving the modeling of terrestrial transpiration in arid and semi-arid regions 总被引:1,自引:0,他引:1 下载免费PDF全文
Xintao Liu Xingjie Lu Shulei Zhang Zhongwang Wei Nan Wei Shupeng Zhang Hua Yuan Wei Shangguan Shaofeng Liu Jianfeng Huang Lu Li Xiulan Ye Jinxuan Zhou Wenke Hu Yongjiu Dai 《大气和海洋科学快报》2022,15(1):35-41
陆面过程蒸腾作用的模拟制约着天气,气候降水预测的精确度.近几十年来,为了更好地描述植被蒸腾的水力约束,陆面过程模式发展了基于植物性状的植物水力胁迫方案.然而,我们对于植物性状在蒸腾模拟中的地位仍然缺乏了解,植物性状对蒸腾的重要性仍需进一步量化.本研究利用Morris方法评估植物性状参数在通用陆面模式植物水力胁迫方案(CoLM-P50HS)中的重要性,针对17种植物性状,筛选出最为重要的:耐旱性状(P50),气孔性状,和光合作用性状.在12个FLUXNET站点中,参数的重要性由归一化敏感度来衡量.P50的重要性随着降水的减少而增加,而气孔性状和光合作用性状的重要性则随着降水的减少而减少.在干旱或半干旱地区,P50比气孔性状和光合作用性状更重要,这意味着当植物经常经历干旱时,水力安全策略比植物生长策略更关键.而耐旱性状的巨大变异性进一步暗示了多种植物水力安全策略的共存.忽视P50的变异性可能会对陆面过程模式蒸腾作用的模拟造成严重误差.因此,为了更好地表示植物水力功能的变异性,需要增加对耐旱性状的观测并耦合到陆面模式中. 相似文献
87.
Possible link between new coronavirus variants and atmospheric lightning and seawater intrusion 下载免费PDF全文
自新型冠状病毒肺炎暴发一年多以来,已经对全球产生深远影响.新型冠状病毒肺炎变异毒株的出现使当前疫情发展充满了不确定性.从这方面出发,我们讨论病毒变异与大气因素之间的联系.根据固氮过程和硝酸盐在人体中的转化过程,我们提出了新型冠状病毒肺炎变异毒株的出现或许和闪电以及海水入侵有联系.我们的研究对新型冠状病毒肺炎变异毒株可能的产生原因提供新的观点. 相似文献
89.
Climate Dynamics - Energetic feedbacks play important roles during the El Niño-Southern Oscillation (ENSO). Here we conduct a thorough analysis of the radiative and non-radiative vertical... 相似文献
90.
Interannual variability of the sea surface salinity and its related freshwater flux in the tropical Pacific: A comparison of CMIP5 and CMIP6 下载免费PDF全文
This paper assesses the interannual variabilities of simulated sea surface salinity (SSS) and freshwater flux (FWF) in the tropical Pacific from phases 5 and 6 of the Coupled Model Intercomparison Project (CMIP5 and CMIP6). The authors focus on comparing the simulated SSS and FWF responses to El Niño–Southern Oscillation (ENSO) from two generations of models developed by the same group. The results show that CMIP5 and CMIP6 models can perform well in simulating the spatial distributions of the SSS and FWF responses associated with ENSO, as well as their relationship. It is found that most CMIP6 models have improved in simulating the geographical distribution of the SSS and FWF interannual variability in the tropical Pacific compared to CMIP5 models. In particular, CMIP6 models have corrected the underestimation of the spatial relationship of the FWF and SSS variability with ENSO in the central-western Pacific. In addition, CMIP6 models outperform CMIP5 models in simulating the FWF interannual variability (spatial distribution and intensity) in the tropical Pacific. However, as a whole, CMIP6 models do not show improved skill scores for SSS interannual variability, which is due to their overestimation of the intensity in some models. Large uncertainties exist in simulating the interannual variability of SSS among CMIP5 and CMIP6 models and some improvements with respect to physical processes are needed.摘要通过比较CMIP5和CMIP6来自同一个单位两代模式模拟, 表明CMIP5和CMIP6均能较好地模拟出热带太平洋的海表盐度 (SSS) 和淡水通量 (FWF) 对ENSO响应的分布及其响应间的关系. 与CMIP5模式相比, 大部份CMIP6模式模拟的SSS和FWF年际变化分布均呈现改进, 特别是纠正了较低的中西太平洋SSS和FWF变化的空间关系. 但是, 整体上, CMIP6模式模拟的SSS年际变化技巧没有提高, 与SSS年际变率的强度被高估有关. CMIP5和CMIP6模式模拟SSS的年际变化还存在较大的不确定性, 在物理方面需要改进. 相似文献