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11.
Changes of Precipitation Infiltration Recharge in the Circumstances of Coal Mining Subsidence in the Shen‐Dong Coal Field,China 总被引：3，自引：0，他引：3
Coal mining subsidence is a universal environmental-geological problem in mining areas. By selecting the Shen-Dong coal mining subsidence area as the research field, this paper studies the changes in precipitation infiltration recharge in the circumstances of coal mining subsidence by means of field geological investigation and laboratory simulation experiments, which is expected to provide a scientific basis for eco-environmental restoration in the mining area. The results indicate that at the unstable stage of subsidence, three types of subsidence in the Shen-Dong mining area have positive effects on the precipitation infiltration recharge, and the type of full-thickness bedrock subsidence has the greatest influence. In the stable stage of subsidence, the precipitation infiltration process after long-term drought and the moisture migration in the aeration zone undergo three different stages: evaporation-infiltration before precipitation, infiltration-upward infiltration-infiltration during precipitation and evaporation-infiltration after precipitation. During a heavy rainfall infiltration process, the wetting front movement in fine sand, coarse sand and dualistic structure of fine-coarse sand consists of two stages: the stage of wetting front movement during precipitation, in which the wetting front movement distance has linear relationship with the depth, and the stage of wetting front movement after precipitation, in which the wetting front movement distance has the power function relationship with the depth. The wetting front movement velocity is influenced by the rainfall amount and the lithology in the aeration zone. However, as the depth increases, the movement velocity will decay exponentially. 相似文献
12.
LI Jianfeng XIA Bin XIA Lianze XU Lifeng LIU Weiliang CAI Zhourong YANG Zhiqing 《《地质学报》英文版》2013,87(6):1603-1616
The wedge shaped Dong Tso ophiolitic block is distributed near the transition point from the western to the middle sub-belt of the Bangong-Nujiang suture zone.The ophiolite is characterized by well-developed cumulate rocks that are mainly composed of cumulate and massive gabbros.In the cumulate gabbros,the adcumulate amphiboles are distributed extensively around the plagioclase and residual pyroxene grains; hence,the rocks are named adcumulate amphibole-gabbro.In this study,the formation age of the ophiolite has been estimated to be 166 ± 4 million years （Ma） by the sensitive high-resolution ion microprobe （SHRIMP） Ⅱ U-Pb isotopic analysis of the zircons from the adcumulate amphibole-gabbro; the 40Ar/39Ar plateau age was estimated to be 148.19 ± 1.53 Ma,which should represent the emplacement time of the ophiolite,by isotopic dating of the pure amphibole mineral from the amphibole-schist.Two different suits of volcanic lavas have been recognized in this work.The purple colored pillow basalts have high TiO2 and P2O5 contents,and are rich in light rare earth elements （LREEs）,large-ion lithospheric elements （LILEs） and high-field-strength elements （HFSEs）,the characteristics that are the typical of the oceanic island basalt （OIB）.On the other hand,other massive basaltic andesites of celadon color are poor in MgO; rich in Fe2O3,LREEs,LILEs,and HFSEs; and especially characterized by negative Nb and Ta anomalies,the properties that establish the andesites as continental arc volcanic rocks.It is concluded that hotspots had developed in the old Dong Tso basin,the oceanic basin that had been developing from middle Jurassic （166 Ma） or even before and emplaced northward in late Jurassic （about 148 Ma）. 相似文献
13.
内蒙古东乌旗宾巴勒查干分布有大面积三叠纪花岗岩,是研究中亚造山带中东部早中生代构造演化的有利地区。在区域地质调查的基础上,利用同位素年代学在该区识别出三叠纪两期侵入岩:中三叠世二长花岗岩类(238~230 Ma)和晚三叠世正长花岗岩类(223~215 Ma)。采用矿物化学、岩石地球化学等方法对两类侵入岩进行了研究:前者中黑云母为镁质黑云母,岩石以高硅、富钾、过铝、钙碱性为特征,稀土元素中轻稀土相对富集、具明显的负Eu异常,微量元素以相对富集大离子亲石元素、具明显的Ba负异常为特征,地球化学特征介于I型和A型花岗岩之间;后者中黑云母由镁质黑云母向铁质黑云母转变,岩石以高硅、富碱、富钾、弱过铝为特征,稀土、微量元素特征与前者相似,但稀土总量相对较低,Eu、Ba的负异常程度更大,属A型花岗岩。二者可能源于年轻幔源组分形成下地壳的部分熔融。结合区域资料分析,研究区三叠纪侵入岩形成于古亚洲洋闭合背景下,中三叠世时可能处于后造山伸展背景,晚三叠世可能为板内构造背景。 相似文献
14.
胶东半岛的地质灾害及防治对策建议 总被引：1，自引：0，他引：1
胶东半岛地处东北亚,是带动山东半岛乃至全省经济超常规、高速度、跨越式发展的"龙头"区域。近年来,随着经济高速发展,在地质环境脆弱地区诱发的地质灾害逐渐加剧。本文分析了胶东半岛地质环境条件及其与地质灾害的相关性,对胶东半岛地震灾害、地面变形灾害、斜坡环境变异灾害、流体灾害等地质灾害的特征、成因、危害及其防治对策进行了系统的分析,并提出了相应的防治对策。 相似文献
15.
东川地质灾害成灾特点及减灾社会化 总被引：3，自引：2，他引：3
云南省昆明市东川区是著名的泥石流多发地区,有灾害性泥石流沟70条、滑坡163个,其它地质灾害主要有地震、地裂、地陷、危岩、水土流失等.灾害非常严重,仅泥石流平均每年注入金沙江1 000×104m3泥沙,东川区的地质灾害有分布地域广泛、类型多样、成灾严重、灾害频发、预防和治理难度大等特点.多年来对危害严重的20多条重点滑坡泥石流沟进行整治并取得明显效果.为加强面上80多条泥石流沟及100多个滑坡的灾害预防和治理,应该以地质灾害主管的国土部门为主,调动各方及群众积极因素,做到主动预防,制定减灾预案群策群防,使减灾社会化,才能最有效地全面控制地质灾害的危害. 相似文献
16.
内蒙古东乌旗阿尔哈达银铅锌矿区地质、物化探特征及其找矿意义 总被引：5，自引：2，他引：5
在内蒙古东乌旗阿尔哈达矿区通过地质、物、化探综合手段进行找矿,取得了良好效果,现已发现3个成矿带,仅在Ⅰ号矿带就发现规模不等的矿体近20个,初步概算银、铅锌资源量已达到中型矿床规模.该矿区的找矿经验对在草原覆盖区开展找矿工作具有指导意义. 相似文献
17.
在内蒙古东乌旗阿尔哈达矿区通过地质、物、化探综合手段进行找矿，取得了良好效果，现已发现3个成矿带，仅在Ⅰ号矿带就发现规模不等的矿体近20个，初步概算银、铅锌资源量已达到中型矿床规模。该矿区的找矿经验对在草原覆盖区开展找矿工作具有指导意义。 相似文献
18.
以Qu ick B ird全色和多光谱影像为数据源,通过波段组合、HIS变换融合使处理后图像达到分辨率高而且接近真彩色,具有良好的识别效果;利用野外采集的6个高精度的GPS地面控制点对影像进行二次多项式几何精校正;利用校正后的影像对东大滩地表破裂带进行了应用性研究,结果表明:在空气稀薄、气候寒冷、野外考察条件极其艰苦的东大滩,通过0.61 m分辨率的Qu ick B ird影像可以较形象、直观、真实地反映东大滩破裂带的几何特征和形态特征。 相似文献
19.
Holocene Saline Sedimentary Record in Tibetan Dong Co (Lake) and Its Significance on Palaeoclimate 总被引：2，自引：0，他引：2
HOLOCENE SALINE SEDIMENTARY RECORD IN TIBETAN DONG CO(LAKE) AND ITS SIGNIFICANCE ON PALAEOCLIMATE 相似文献
20.
1017高地银多金属矿床位于内蒙古自治区东乌珠穆沁旗,矿区大地构造位置处于西伯利亚板块东南缘查干敖包-奥尤特-朝不楞早古生代构造-岩浆岩带东段。石英脉型矿石中流体包裹体研究显示,从成矿早期到主成矿期,流体温度逐渐降低(从404℃~134℃到236℃~121℃),盐度都为中低盐度,由此表明该矿床具有浅成、中低温、中低盐度热液成矿特征。激光拉曼光谱分析显示包裹体气液相成分主要为H2O。矿石硫同位素组成相对均一,δ34S介于3.4‰~8.0‰之间,均值5.35‰,与幔源S的δ34S值(介于-3‰~3.0‰之间)比较,有向沉积硫的明显漂移,表明矿石中硫来源于沉积硫与岩浆硫的混合、平衡作用;矿石硫化物铅同位素比值没有明显的差别,206Pb/204Pb值为18.274 0~18.399 6,207Pb/204Pb值为15.539 9~15.561 6,208Pb/204Pb值为38.036 3~38.177 2,具有钍铅微弱亏损特征,指示矿石中硫化物的铅源主要来自地壳深部的岩浆源区,伴随岩浆及其热液作用,不可避免地混入了部分富放射成因铅的地壳物质。矿石氢氧同位素组成为:δDV-SMOW值介于-103‰~-125‰之间,δ18 OV-SMOW值在6.9‰~13.9‰之间,显示成矿流体中的水来源于岩浆水与大气降水的混合。综合1017高地银多金属矿床的地质特征和流体包裹体、S,Pb,H,O同位素研究认为,该矿床成矿物质来源于深源岩浆和上地壳的混合,成矿流体主要来自岩浆期后热液和大气降水,其成因类型可归于中低温度、中低盐度的岩浆期后热液型银多金属矿床。 相似文献