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261.
矿床在形成后常被构造改造,但现有三维成矿预测中对其关注较少。笔者选择胶东半岛大尹格庄构造蚀变岩型金矿为研究对象,采用基于不规则三角网(TIN)的构造复原方法还原被断裂错断的矿体与控矿断裂的三维结构,开展复原前后的矿化空间/控矿因素对比分析并实现深边部三维成矿预测。结果表明,构造复原方法消除了断裂和矿体被错断产生的空间距离及倾角变化;复原后的矿化分布具有更强的空间自相关性,被错断区域的矿化分布由分散变为连续。此外,相同参数下,复原后的预测模型比复原前模型具有更高的性能,说明对复原后的矿化分布和控矿指标之间的关联关系表达更加显著。因此,顾及构造改造的三维成矿预测有利于预测结果的准确性,可为大尹格庄矿床深部找矿工作提供可靠参考。 相似文献
262.
The Response of Anomalous Vertically Integrated Moisture Flux Patterns Related to Drought and Flood in Southern China to Sea Surface Temperature Anomaly 下载免费PDF全文
With the extreme drought (flood) event in southern China from July to August in 2022 (1999) as the research object, based on the comprehensive diagnosis and composite analysis on the anomalous drought and flood years from July to August in 1961-2022, it is found that there are significant differences in the characteristics of the vertically integrated moisture flux (VIMF) anomaly circulation pattern and the VIMF convergence (VIMFC) anomaly in southern China in drought and flood years, and the VIMFC, a physical quantity, can be regarded as an indicative physical factor for the "strong signal" of drought and flood in southern China. Specifically, in drought years, the VIMF anomaly in southern China is an anticyclonic circulation pattern and the divergence characteristics of the VIMFC are prominent, while those are opposite in flood years. Based on the SST anomaly in the typical draught year of 2022 in southern China and the SST deviation distribution characteristics of abnormal draught and flood years from 1961 to 2022, five SST high impact areas (i.e., the North Pacific Ocean, Northwest Pacific Ocean, Southwest Pacific Ocean, Indian Ocean, and East Pacific Ocean) are selected via the correlation analysis of VIMFC and the global SST in the preceding months (May and June) and in the study period (July and August) in 1961-2022, and their contributions to drought and flood in southern China are quantified. Our study reveals not only the persistent anomalous variation of SST in the Pacific and the Indian Ocean but also its impact on the pattern of moisture transport. Furthermore, it can be discovered from the positive and negative phase fitting of SST that the SST composite flow field in high impact areas can exhibit two types of anomalous moisture transport structures that are opposite to each other, namely an anticyclonic (cyclonic) circulation pattern anomaly in southern China and the coastal areas of east China. These two types of opposite anomalous moisture transport structures can not only drive the formation of drought (flood) in southern China but also exert its influence on the persistent development of the extreme weather. 相似文献