地质通报
地質通報
지질통보
GEOLOGICAL BULLETIN OF CHINA
2015年
1期
32-44
,共13页
姚鑫%李凌婧%张永双%郭长宝%周能娟
姚鑫%李凌婧%張永雙%郭長寶%週能娟
요흠%리릉청%장영쌍%곽장보%주능연
区域地壳稳定性%青藏高原东缘%龙门山断裂%活动断裂%地质灾害
區域地殼穩定性%青藏高原東緣%龍門山斷裂%活動斷裂%地質災害
구역지각은정성%청장고원동연%룡문산단렬%활동단렬%지질재해
regional crustal stability%eastern margin of Tibetan Plateau%active fault%geo-hazard%earthquake
青藏高原东缘新构造运动复杂而强烈,地震与地质灾害多发,区域地壳稳定性评价工作意义重大。基于地质力学和大陆动力学相互补充的区域地壳稳定性评价理论,选择深部地球物理场、区域构造变形、地震活动、区域构造应力场作为内动力因素,地形地貌、降雨量、河流冲蚀组合计算所产生的地质灾害条件作为外动力因素,地层岩性和活动断裂影响带作为介质因素,进行了区域地壳稳定性评价。结果表明,采用地质要素梯度来反映内动力作用和通过地质环境要素综合分析表现外动力作用是提高评价准确性的有效手段;青藏高原东缘可分为8个构造特征差异显著的一级分区,75个综合因素差别较大的二级分区,653个外动力条件有一定差别的三级分区;总体而言,龙门山断裂、鲜水河断裂和安宁河断裂带构成的Y字型构造格架断裂带附近的地壳稳定性最差,西部次之,东部最好,北部区块较完整,南部复杂破碎。
青藏高原東緣新構造運動複雜而彊烈,地震與地質災害多髮,區域地殼穩定性評價工作意義重大。基于地質力學和大陸動力學相互補充的區域地殼穩定性評價理論,選擇深部地毬物理場、區域構造變形、地震活動、區域構造應力場作為內動力因素,地形地貌、降雨量、河流遲蝕組閤計算所產生的地質災害條件作為外動力因素,地層巖性和活動斷裂影響帶作為介質因素,進行瞭區域地殼穩定性評價。結果錶明,採用地質要素梯度來反映內動力作用和通過地質環境要素綜閤分析錶現外動力作用是提高評價準確性的有效手段;青藏高原東緣可分為8箇構造特徵差異顯著的一級分區,75箇綜閤因素差彆較大的二級分區,653箇外動力條件有一定差彆的三級分區;總體而言,龍門山斷裂、鮮水河斷裂和安寧河斷裂帶構成的Y字型構造格架斷裂帶附近的地殼穩定性最差,西部次之,東部最好,北部區塊較完整,南部複雜破碎。
청장고원동연신구조운동복잡이강렬,지진여지질재해다발,구역지각은정성평개공작의의중대。기우지질역학화대륙동역학상호보충적구역지각은정성평개이론,선택심부지구물리장、구역구조변형、지진활동、구역구조응력장작위내동력인소,지형지모、강우량、하류충식조합계산소산생적지질재해조건작위외동력인소,지층암성화활동단렬영향대작위개질인소,진행료구역지각은정성평개。결과표명,채용지질요소제도래반영내동력작용화통과지질배경요소종합분석표현외동력작용시제고평개준학성적유효수단;청장고원동연가분위8개구조특정차이현저적일급분구,75개종합인소차별교대적이급분구,653개외동력조건유일정차별적삼급분구;총체이언,룡문산단렬、선수하단렬화안저하단렬대구성적Y자형구조격가단렬대부근적지각은정성최차,서부차지,동부최호,북부구괴교완정,남부복잡파쇄。
Eastern margin of the Tibetan Plateau is a sharpen change zone of geomorphology and geology, with complex and strong Neotectonic movement, breeding environment of numerous earthquakes and geo-hazards occurred largely. It is of great significance to carry out Regional Crustal Stability Assessment (RCSA). Using RCSA combined geo-mechanics and continental dynamics theo?ry, this paper selected four types data, deep geophysical fields, regional tectonic deformation, regional tectonic stress fields and seismic activity, as internal dynamic factors, geo-hazard combining with topography, rainfall and river erosion as the external factors, litholo?gy and affecting strip of active fault as the medium factors, then to carry out the RCSA. The results show that: ( 1) it is an effective means to improve the assessment accuracy that using geological elements gradient reflects the internal dynamic action and using com?prehensive analysis of geological environment reflects external dynamic action;(2)evaluation results show that the study area can be divided into eight one-class zonations by tectonic characteristics significantly different, 75 secondary zonations by comprehensive fac?tors differences vary greatly, and 653 three-class zonations by outside dynamic conditions;(3)in brief, fault belts near and/or in the tectonic skeleton, composed mainly with Longmenshan fault, Xianshuihe fault, Anninghe fault, are the worst, followed by the west, the east is best, the north relatively complete, and the southern breaking and complex.