西藏隆子县恰嘎村辉锑矿地质特征及找矿潜力          下载免费PDF全文

董富权  李武毅  胡可卫  吕晓春  罗敏玄  高伟先  蒋亚军 《地质找矿论丛》2015,30(1):98-102

西藏隆子县恰嘎村辉锑矿区位于藏南错美—隆子锑金成矿带的中东部,恰嘎村辉锑矿的锑矿化带受近SN向煌斑岩脉与近SN向构造的控制。通过分析恰嘎村辉锑矿地质特征、1∶50000水系沉积物地球化学特征、1∶10 000土壤地球化学特征、1∶10 000物探中梯激电剖面特征和ETM+遥感影像特征等,认为恰嘎村辉锑矿区具有寻找辉锑矿等金属矿产的潜力。  相似文献   

爆管法施工对环境的影响分析     

李鸿翼  马孝春 《岩土钻凿工程》2011,(5):42-45

通过对爆管法对环境影响的理论分析,并结合有关的试验进行模拟分析,探讨了爆管法施工产生的碎片对新铺管道的影响,对周围结构设施的影响,重点论述了爆管法施工引起的地表位移。  相似文献   

广东省滑坡灾害监测中CORS系统的应用分析     

魏平新  李成钢  徐峰  石晓春 《地球信息科学学报》2011,13(4):562-570

在广东省滑坡灾害动态监测工作中,以广东省GPS连续运行参考站网络(GDCORS)技术为核心,集成单频GPS接收机及一机多天线技术(GMS)等低成本专业化GPS形变监测手段,开展高精度(厘米级到毫米级)滑坡灾害动态监测应用研究.在对3种关键技术,包括:CORS系统建立和维护区域动态位移形变监测基准、GPS/CORS动态解...  相似文献   

渤海湾盆地及周边的古生古储油气藏——以双洞背斜古油藏与刘其营、苏桥潜山油气藏为例   总被引：4，自引：0，他引：4  

杨克绳  党晓春  戴福贵 《海相油气地质》2007,12(3):27-32

双洞背斜古油藏、刘其营潜山油气藏、苏桥潜山油气藏均为古生古储或自生自储的油气藏(古油藏)。双洞古油藏位于燕山褶皱带山海关隆起北部,邻近渤海湾盆地,其含油层为中—上元古界铁岭组,而该处根本没有下第三系生油层,说明中—上元古界和古生界是其生烃层。刘其营油气藏位于冀中坳陷,储层为奥陶系,盖层为石炭系—二叠系,其上部新生界主要生油层为沙河街组三段,中间相隔厚度约1000～3000m的沙河街组四段和孔店组隔层。沙河街组三段所生之油气,无法穿过这一隔层及不整合面向下运移到奥陶系储层中,因此刘其营潜山油气藏也不可能是新生古储的。苏桥油气藏是一复式油气藏,上部石炭系—二叠系气藏与下部奥陶系油藏叠合,根据油、气、水性质的对比也可以排除新生古储的成藏模式。渤海湾盆地古生界和中—上元古界具有生烃能力,其中的临清坳陷具备在深部古老地层寻找原生油气藏的条件。  相似文献   

东南极古陆核的研究现状、问题与设想     

刘晓春  赵越  王伟  陈龙耀  郑光高  刘健  王亚飞  任留东 《地质力学学报》2021,27(5):691-704

东南极地盾(克拉通)中的太古宙陆核主要分布在面向印度洋扇区的内皮尔山、南查尔斯王子山、赖于尔群岛和西福尔丘陵,在面向澳大利亚、非洲和太平洋扇区只零星出露。这些古陆核被早元古代—早古生代(泛非期)造山带所分割,它们具有不同的早期演化历史和后期改造过程,并且产于不同扇区的陆核与相邻冈瓦纳陆块具有密切的亲缘关系。对东南极古陆核开展系统的冰上和冰下地质调查以及岩石地球化学综合研究,查明太古宙岩石(物质)的时空分布、岩石成因、源区性质、构造属性及其变质改造历史,进而构建东南极古大陆从初始成核到最终聚陆的历史框架,这将弥补地球早期演化研究领域的南极短板,同时也必将促进地球早期演化研究领域的发展。   相似文献   

滇东北会泽地区南红玛瑙产出特征及成因分析          下载免费PDF全文

刘德民  吕晓春  黄锦山  邵俊琦  李致伟  程炎勋 《地质找矿论丛》2018,33(4):548-553

会泽地区的南红玛瑙矿主要产于上三叠统飞仙关组的中上部砾岩层、上二叠统宣威组底部砾岩层以及晚二叠世峨眉山组杏仁状玄武岩中。玛瑙新鲜面多为红色、浅红色及灰白色;呈椭球状或扁球状分布于砾岩之中,分布不均匀,局部富集;玛瑙砾石大小不一,玛瑙粒径多集中在0.5~5 cm,偶见大于6 cm。会泽地区的南红玛瑙矿形成可分为三个阶段：1）晚二叠世时期,玄武质火山岩（P₃e）中的含硅质热液在晚期充填于玄武岩气孔或裂隙中,经过（快速）冷却形成隐晶质石英或晶质石英集合体——玛瑙,即原生玛瑙;2）晚二叠世晚期的华力西运动和印支运动早期的地壳继续隆升,使得含玛瑙玄武岩遭受风化-剥蚀作用,两次剥离出来的玛瑙单体经流水搬运作用及河湖相沉积作用,形成宣威组（P₃x）、飞仙关组（T₁f）含玛瑙砾石层——沉积砾岩型玛瑙矿产;3）近-现代地质作用,使得二叠纪玄武岩气孔中原生玛瑙和宣威组、飞仙关组沉积砾岩层中的次生玛瑙砾石,再次受到风化-剥蚀作用,玛瑙砾石经流水搬运至现代河流或湖泊中,形成次生玛瑙砂矿。  相似文献   

Characteristics of Holocene Loess-Palaeosol Particle Size Composition and Paleoclimatic Significance in East Guanzhong,Shaanxi Province     

Zhaoduo Wang  Chunchang Huang  Yali Zhou  Jiangli Pang  Xiaochun Zha 《地球科学进展》2018,33(3):293-304

This paper made an end-member analysis of particle size data collected from 150 samples based on the continuous Holocene Loess-Paleosol profile (Yaohecun profile) in east Guanzhong, Shaanxi Province. Wavelet analysis was also performed for the EMs along the time scale of depth.The result shows that three end members can be separated from different sediment particle sizes. Based on comparative analysis of magnetic susceptibility and geochemical index, it was considered that the End-member 1 might indicate the weathering and pedogenic remoulding after sediment deposition under the east Asian summer monsoon. The End-member 2 might indicate dynamic effect of dust storm accumulation under the influence of northwest monsoon, representing typical component characteristics of aeolian loess.The End-member 3 indicated the stronger transporting force for coarse components, which should belong to the northeasterly winds for the coarse-grained near-source sediments from the Yellow River flood plain. Results of wavelet analysis show that each EM has different periodic characteristics at 1.5 ka, 3.0 ka and 4.5 ka scales.The End-element analysis method has a good effect in indicating the sedimentary environment and provenance characteristics of sediments. The combination characteristics of each End-member can reflect the characteristics of sedimentary dynamics combination and can well reflect the Holocene dynamic change course. At the same time, it hasreference significance to reconstruct the paleoclimate on the longer time scale.The wavelet analysis method provides significant results in terms of inversion cycles and trends of dynamics change of sedimentary particle size within each EM.  相似文献   

河南晚更新世—全新世黄土记录的环境变化及物源特征          下载免费PDF全文

王兆夺  黄春长  周亚利  庞奖励  查小春  郭永强 《高校地质学报》2018,24(3):380

基于河南新郑县的一套完整晚更新世—全新世黄土古土壤剖面(格大张剖面),应用端元分析模型,对75个沉积样品的粒度分析数据进行分析,并对各端元组分在地层深度对应的时间尺度上做了小波变换。结果认为,从格大张剖面沉积物粒级组分中可以分离出三个沉积端元,端元1可能指示了东亚夏季风作用动力特征,夏季风的强弱引起的温湿变化造成相应时期内沉积物的古土壤化的强弱;端元2可能指示了东亚冬季风作用下沙尘暴沉积动力作用特征,代表了典型风成黄土的粗颗粒组分特征;端元3粒级组分更粗,代表了更强搬运动力条件,应属于东北风搬运黄泛平原粗颗粒而来的近源沉积物,距今3100 a以来尤为显著。根据小波分析结果,认为各端元组分在不同的时间尺度上具有周期性特点。端元分析法在指示沉积物沉积动力环境和物源特征上具有很好的效果,各端元组合特征能够敏感地反映出沉积动力组合特征,很好地反映晚更新世以来各动力变化特征。采用小波分析方法对识别各端元组的周期性特征以及根据目前状态推断未来可能的趋势具有参考意义。  相似文献   

Experimental and theoretical study on the effect of unsteady flow on the fracturing pressure in hydraulic fracturing test     

Mingze Liu  Guang Zhang  Guogang Gou  Bing Bai  Shaobin Hu  Xiaochun Li 《Natural Hazards》2018,90(3):1137-1151

Reasonable determination of formation fracturing pressure concerns the stable operation of underground fluid injection projects. In this work, we studied the effect of unsteady flow on fracturing pressure. Hydraulic fracturing tests on low permeable sandstone were conducted with the injection rate between 0.1 and 2.0 ml/min. Then, the fracturing pressure prediction models for hollow cylinder under both unsteady flow and steady flow conditions were deduced. Finally, the effect of unsteady flow on the fracturing pressure was studied based on the experimental result and several influence factors. It was shown that fracturing pressure increased with the elevated pressurization rate in the tests, while the slope of the variation curve decreases. The model considering unsteady flow can reflect the variation tendency of fracturing pressures in experiments, while fracturing pressures from the model considering steady flow are invariant with different pressurization rates. Fracturing pressure decreases with the elevated rock permeability and increases with the elevated fluid viscosity, and these two effects are actually generated by the unsteady flow. Whether to consider the unsteady flow has no significant influence on the effect of rock tensile strength on fracturing pressure when the tensile strength is very low. However, when the tensile strength is high, the effect of unsteady flow cannot be neglected.  相似文献   

Phenological metrics-based crop classification using HJ-1 CCD images and Landsat 8 imagery   总被引：1，自引：0，他引：1  

Xiaochun Zhang  Qinxue Xiong  Liping Di  Junmei Tang  Jin Yang  Huayi Wu 《International Journal of Digital Earth》2018,11(12):1219-1240

Crop type data are an important piece of information for many applications in agriculture. Extracting crop type using remote sensing is not easy because multiple crops are usually planted into small parcels with limited availability of satellite images due to weather conditions. In this research, we aim at producing crop maps for areas with abundant rainfall and small-sized parcels by making full use of Landsat 8 and HJ-1 charge-coupled device (CCD) data. We masked out non-vegetation areas by using Landsat 8 images and then extracted a crop map from a long-term time-series of HJ-1 CCD satellite images acquired at 30-m spatial resolution and two-day temporal resolution. To increase accuracy, four key phenological metrics of crops were extracted from time-series Normalized Difference Vegetation Index curves plotted from the HJ-1 CCD images. These phenological metrics were used to further identify each of the crop types with less, but easier to access, ancillary field survey data. We used crop area data from the Jingzhou statistical yearbook and 5.8-m spatial resolution ZY-3 satellite images to perform an accuracy assessment. The results show that our classification accuracy was 92% when compared with the highly accurate but limited ZY-3 images and matched up to 80% to the statistical crop areas.  相似文献