康定杂岩Rb-Sr、Sm-Nd同位素系统及其意义

通过对康定—冕宁地区出露的英云闪长岩、黑云角闪斜长片麻岩、角闪变粒岩全岩及其中所分离出的角闪石、黑云母、斜长石、钾长石的Rb-Sr、Sm-Nd同位素的系统测定,结合岩石的锆石U-Pb年龄结果,确定这些变质杂岩由于经历了复杂的形成过程与变质历史,Rb-Sr、Sm-Nd同位素体系难以确定其结晶年龄。由单矿物与全岩Rb-Sr、Sm-Nd体系拟合的~700 M a的等时线年龄反映了角闪岩相-高角闪岩相的变质作用年龄。Sm-Nd同位素体系由于在变质作用过程中的部分开放性,很容易给出无意义的较老的混合年龄。康定杂岩结晶后并没有经历麻粒岩相变质作用,区域上所含的麻粒岩透镜体可能是新元古代(773~721 M a)期间由Rod in ia超大陆裂解产生的新生洋壳向扬子克拉通陆块俯冲消减过程的变质产物。俯冲到一定深度后,由于板片被拉断,软流圈上涌导致变质洋壳板片岩石、先前底侵变质的镁铁质岩石及扬子陆块长英质基底岩石发生部分熔融,以镁铁质岩石熔融产生的熔浆为主(>70%),与长英质基底岩石熔融产生的熔浆混合形成w(Na2O)/w(K2O)>1的TTG组合。     

东濮凹陷桥口构造沙三段储层成岩作用与孔隙演化

通过薄片观察、鉴定可知,桥口地区沙河街三段储集层砂岩成岩作用主要有压实作用、胶结作用、交代作用和溶蚀作用．孔隙以粒间溶孔、粒内溶孔和胶结物溶孔等次生溶孔为主．经粘土矿物X衍射分析,将成岩阶段划分为早成岩A、B期和晚成岩A1、A2、B期,早成岩A、B期的机械压实和胶结作用使原生孔隙大量丧失,晚成岩A1溶蚀作用对储层孔隙起重要改善作用,增加大量次生孔隙,晚成岩A2、B期方解石胶结物的胶结作用使砂岩次生孔隙大量减少．因此早期原牛孔隙的大量散失、晚期胶结作用使次生孔隙大量减少是造成本区砂岩低孔、低渗的主要原因．     

Geochemical characteristics and source analysis of inflow of mine water in Wang’ershan Gold Mine, Shandong

Through a systematic observation of water level and temperature, and a comprehensive analysis of the data on major/trace elements, nitrite, hydrogen-oxygen isotopes, the conclusion has been drawn that there are two relatively independent groundwater systems (cool water and hot water), and the geochemical indicators of hot/cool waters are described. The cool water system is relatively enriched in Ca2 , Mg2 and HCO3-. Its TDS is relatively low, about 1400–1800 mg/L. The hot water system is relatively enriched in K , Na , Cl- and SO42-. Its TDS is relatively high, about 2200–2300 mg/L. The cool water system is enriched in Ba, Ga, Cd, and the hot water system is enriched in B, Ti, Cr, Ni, Cu, Mo, Rb, and Cs, relatively. Especially, the contents of Rb and Cs in the hot water system are more than five times as high as those in the cool water system. The NO3- contents of cool water discharged from the gold mine are relatively high, and those of hot water are extremely low. The δD and δ18O values follow an increasing order of surface water>mine cool water>mine hot water. The cool water comes mainly from the lateral supply of phreatic water, while the hot water comes mainly from the vertical supply of deeply circulating structure-fracture water. The ratio of cool water over hot water was estimated to be about 1:1 by a water quality model..     

Environmental Investigation and Evaluation of Land Subsidence in the Datong Coalfield Based on InSAR Technology

Heavy mining of Jurassic and Carboniferous horizontal coal seams in the Datong coalfield has seriously affected the local geological environment, which is mainly manifested by such geohazards as soil avalanches, landslides, mudflows, surface subsidence, surface cracks, surface solid waste accumulation and surface deformation. More seriously, coal mining causes groundwater to leak. Overpumping of groundwater has resulted in substantial land subsidence of the urban area in Datong City. Based on the previous geo-environmental investigation in the work area, the authors used radar remote sensing techniques such as InSAR （synthetic aperture radar interferometry） and D-InSAR （differential synthetic aperture radar interferometry）, supplemented by the optical remote sensing method, for geo-environmental investigation to ascertain the geo-environmental background of the Datong Jurassic and Carboniferous-Permian coalfield and evaluate the effects of the geohazards, thus providing a basis for the geo-environmental protection, geohazard control and prevention, land improvement and optimization of the human environment. In this study 8 cog-nominal ERS-1/2 SAR data frames during 1992 to 2003 were used, but the following processing was made： （1） the multitemporal SAR magnitude images were used to interpret the geological structure, vegetation, microgeomorphology and drainage system; （2） the multi-temporal InSAR coherent images were used to make a classification of surface features and evaluate the coherence change due to coal mining; and （3） the multi-temporal cog-nominal SAR images were used to complete D-InSAR processing to remove the information of differential deformation areas （sites）. In the end, a ten-year time series of differential interferograms were obtained using the multi-temporal cog-nominal SAR images. In the tests, 84 deformed areas （sites） were obtained, belonging to those in 1993-1996, 1996-1997, 1997-1998, 1998-2001, 1998-2002 and 2001-2003 respectively. Of the 84 areas, 44 are m     

The Role of Fracture Structure in Leachate Pollution at Landfills： A Case Study of a Landfill in Chongqing City

This paper studies a landfill where there are three faults running through.As serious pollution has occurred to the geological environment,the landfill is to be closed up and renovated.The paper aims to explore the role of fracture structure in leachate pollution at the landfill.The research was carried out in several stages.First,mathematical models of the pre-renovation landfill with three faults running through and the landfill after renovation were established.And then,the boundary conditions and parameters of the two mathematical models were determined.The groundwater level of the landfills was simulated in order to modify the two mathematical models.As a result,a feasible mathematical model was achieved.Based on this model,a comparison was made of the COD concentration variations in the inside leachate and outside leachate between the two landfills. Accordingly,the impacts of the fracture structure on the pollution of leachate at the landfills could be identified.The study results show that while faults contribute to the migration of leachate,they also serve as a confluence of leachate,thus further deteriorating the environment.The COD concentrations of the inside leachate and the outside leacbate of the pre-renovation landfill are respectively 800 mg/L and 220 mg/L higher than those of the post.renovation landfill.Therefore,measures must be taken to handle the leachate seepage in areas where there are faults as well as the neighboring areas so as to get the environmental pollution under control.     

Petroleum Migration Direction of the Silurian Paleo-pools in the Tarim Basin, Northwest China

The results obtained in this paper indicate that carbazole-type compounds have high thermal stability and also show stability in oxidation and bio-degradation. This kind of compounds still has a high concentration and complete distribution in the analyzed dry asphalt samples, showing that they are particularly useful in studying petroleum migration of paleo-pool. During the basin＇s first-stage of oil-gas pool formation in the Silurian in Tazhong and Tabei areas of Tarim Basin （at the end of Silurian period） and the second-stage in the Awati area （in Permian）, the petroleum experienced a long-distance migration. During the formation of the Silurian paleo-pools in Tazhong Uplift at the end of Silurian, the petroleum mainly came from the lower and middle Cambrian source rocks in the Manjiaer sag. The petroleum migrated towards the southwest-south entering the Silurian reservoir beds in Tazhong first. Then, it further migrated within Silurian from northwest to southeast along the highs of the Structural Belts to the region of the Silurian pinchout boundary in Tazhong. In Tabei Uplift, during the first-stage of pool formation, the petroleum was also from the lower and middle Cambrian source rocks in the Manjiaer sag. It migrated northwest entering the Silurian reservoir beds in the Tabei Uplift firstly, and then the migration continued in the same direction within the Silurian reservoirs and finally the petroleum was trapped in higher positions. During the second-stage pool formation in the Silurian beds in the areas around Awati sag, the petroleum mainly came from the lower-middle Cambrian source rocks in the Awati sag. The petroleum migrated from the generation center to Silurian reservoirs in all directions around the sag through major paths, and the petroleum was finally trapped in higher locations.     

The Role of Fracture Structure in Leachate Pollution at Landfills: A Case Study of a Landfill in Chongqing City

This paper studies a landfill where there are three faults running through. As serious pollution has occurred to the geological environment, the landfill is to be closed up and renovated. The paper aims to explore the role of fracture structure in leachate pollution at the landfill. The research was carried out in several stages. First, mathematical models of the pre-renovation landfill with three faults running through and the landfill after renovation were established. And then, the boundary conditions and parameters of the two mathematical models were determined. The groundwater level of the landfills was simulated in order to modify the two mathematical models. As a result, a feasible mathematical model was achieved. Based on this model, a comparison was made of the COD concentration variations in the inside leachate and outside leachate between the two landfills. Accordingly, the impacts of the fracture structure on the pollution of leachate at the landfills could be identified. The study results show that while faults contribute to the migration of ieachate, they also serve as a confluence of leachate, thus further deteriorating the environment. The COD concentrations of the inside leachate and the outside leachate of the pre-renovation landfill are respectively 800 mg/L and 220 mg/L higher than those of the post-renovation landfill. Therefore, measures must be taken to handle the ieachate seepage in areas where there are faults as well as the neighboring areas so as to get the environmental pollution under control.     

基于小波变换的全色和多光谱遥感图像融合

基于多分辨率小波变换,针对高分辨率全色图像和多光谱图像的融合,提出了一种基于方向可调滤波器的区域能量测量的小波变换融合算法.将此方法与HIS和传统小波的融合方法比较,结果表明,该方法在保留多光谱图像光谱信息的同时,能够更好地保留高分辨率图像的空间信息,融合效果有较大改善.     

地电化学法寻找隐伏金矿的应用研究

通过对金的地电化学成晕机制的研究,利用地电化学法在东北大兴安岭森林覆盖区虎拉林金矿和澳大利亚第四纪厚层覆盖区Challenger金矿进行可行性找矿试验研究。试验结果在上述已知矿区的剖面上均测出了清晰的地电化学异常,表明利用地电化学法在上述地区寻找的隐伏金矿是有效的。在此基础上对两矿区外围及深部进行了找矿预测,发现4个有利的成矿靶区,经工程验证发现2个金矿体,取得了良好的经济和社会经济效益。     

Study on Recovering the Earth＇s Potential Field Based on GOCE Gradiometry

Given the second radial derivative Vrr（P） ｜δs of the Earth＇s gravitational potential V（P） on the surface δS corresponding to the satellite altitude, by using the fictitious compress recovery method, a fictitious regular harmonic field rrVrr（P）^＊ and a fictitious second radial gradient field V：（P） in the domain outside an inner sphere Ki can be determined, which coincides with the real field V（P） in the domain outside the Earth. Vrr^＊（P）could be further expressed as a uniformly convergent expansion series in the domain outside the inner sphere, because rrV（P）^＊ could be expressed as a uniformly convergent spherical harmonic expansion series due to its regularity and harmony in that domain. In another aspect, the fictitious field V^＊（P） defined in the domain outside the inner sphere, which coincides with the real field V（P） in the domain outside the Earth, could be also expressed as a spherical harmonic expansion series. Then, the harmonic coefficients contained in the series expressing V^＊（P） can be determined, and consequently the real field V（P） is recovered. Preliminary simulation calculations show that the second radial gradient field Vrr（P） could be recovered based only on the second radial derivative V（P）｜δs given on the satellite boundary. Concerning the final recovery of the potential field V（P） based only on the boundary value Vrr （P）｜δs, the simulation tests are still in process.