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41.
基于煤巷锚网支护巷道受矿井潮湿环境影响出现的金属网锈蚀断裂、煤壁片帮、巷道失修等实际情况,使用方案比较的方法,分析了喷射混凝土封闭工艺和灰浆喷涂工艺优缺点,进而确定采用防风化喷涂技术进行施工。经实际应用,防风化喷涂技术对鲁村煤矿回风暗斜井的煤壁等四周围岩和锚杆、金属网起到了良好的封闭和防风化效果。保证了巷道正常的回风、行人需要,延长了巷道的服务期限。  相似文献   
42.
斜坡非饱和带低渗透岩石结构体风化前锋扩展过程   总被引:2,自引:0,他引:2  
徐则民 《地学前缘》2008,15(4):258-268
非饱和带低渗透岩石结构体风化前锋扩展是斜坡灾害孕育过程中的关键环节之一。到目前为止,化学风化领域的研究成果主要集中在高水-岩比的饱和环境下单矿物及矿物成分单一的碳酸盐岩的风化动力学方面,非饱和环境下的岩石风化研究还主要限于风化产物的特性描述方面。斜坡非饱和带低渗透岩石结构体风化前锋扩展是一种高度复杂的THMC过程。由于在溶解对象、溶解液及溶解过程的水动力-水化学环境等方面存在的显著差异,既有的地质材料风化动力学成果为探索这一复杂过程提供了理论储备,但还不能阐明其核心机理。斜坡非饱和带低渗透岩石结构体风化前锋的扩展过程研究不仅可以加深人们对斜坡灾害孕育的理解,为灾害预报-预警及其控制提供理论依据,同时可以促进岩石-岩体力学及浅表生水文地球化学等相关学科的交叉与发展。  相似文献   
43.
文章从本区地质成矿规律、物性特征等入手,通过对试验结果的对比分析,论述了古风化壳沉积型铝土矿找矿工作中物探方法的可行性和局限性,提出古风化壳沉积型铝土矿物探工作的系列方案和地球物理异常模式。  相似文献   
44.
The origin of Molar Tooth (MT) carbonates has been argued for more than 100 years, which are a kind of Proterozoic carbonates especially composed of microsparite with ptygmatically folded and sheet-like structures. Biomarkers detected in the microcalcsparite from the Wanlong and Xingmincun formations in the Jilin-Liaoning area showed there are abundant normal alkanes, isoprenoids, hopanes, steranes, alkylmethylcyclohexanes, and alkyleyclohexanes, indicating a diversity of biological source: long-chain isoprenoids, the major components of chlorophyll, such as C19, C20, a kind of major biomarkers synthesized early by isoprenoid monomers; hopanes a type of characteristic biomarkers from prokaryote, such as archaebacteria and cyanobacteria; sterane a biomarker for eukaryote; and two kinds of alkanes with C17, C18 as the main peaks representing aquatic bacteria and with C23, C24 as the main peaks representing fungi, respectively. Biomarker analysis showed that MT is the result of bacterial and algal activities, which is a kind of organisms between aerobic and anaerobic bacteria, reproducing well in normal or slightly saline sea water under weak oxidation-reduction conditions, resulting in rapid deposition of calcite as microsparite clue to some mechanisms.  相似文献   
45.
广西灌阳地区碳酸盐岩层滑断裂构造地球化学系统   总被引:10,自引:1,他引:10  
钱建平 《矿物学报》1994,14(4):348-356
灌阳地区碳酸盐岩中的层滑断裂构造地球化学系统具有典型的结构分带性、变形二重性和成分互补性。在这个系统中存在着Cu→Fe3 →V→Si→Al→Mn→Ba→Ni→Sr→Ag→Bi→Ga→In→Pb→Fe2 →Cr→Co→Zn→Mg→Ca→CO2的稳定性递减序列。影响构造地球化学分异的因素是原岩的性质、应力、温度和流体。构造地球化学作用的基本类型有:动力分异作用、压溶作用和氧化还原作用。层滑断裂带并非还原环境,碳质富集源自有机碳的氧化。Sr是高应力环境同构造重结晶方解石带的特征元素,Zn是低应力环境裂隙充填型方解石脉的特征元素。  相似文献   
46.
不同岩石在相同风化环境条件下的抗风化能力不同。如何评定岩石的抗风化能力是近年来人们十分关注的研究课题之一,因为它对岩石风化机理分析和石质文物长期保护研究有着重要的科学价值。位于浙江省衢州市的古城墙小西门建于明代晚期。小西门城墙的岩石砌块有多种岩性,它们之间的风化剥落深度相差较大。利用三维激光扫描仪测量了小西门某特定研究区中包含多种岩性的岩石砌块的风化剥落深度,并以此来评定不同岩性岩石的长期抗风化能力,以给出相应的排序。在现场还发现,与所研究的多数岩石砌块相比,被古人用作为古城墙各砌块之间勾缝的黏合材料蛎灰的抗风化能力更强。  相似文献   
47.
胶质芽孢杆菌胞外多糖在肥料矿物分解转化中的作用   总被引:3,自引:0,他引:3  
本文探讨了胶质芽孢杆菌胞外多糖在细菌分解转化矿物过程中的作用。将事先提取的胞外粗多糖按一定浓度梯度与矿粉混合,24 h后再次提取多糖称重,证实多糖与矿粉颗粒之间的吸附现象。计算结果表明,矿粉对多糖的吸附随多糖量的增加而呈较明显的增长,之后增幅逐渐趋于平缓。在无氮培养基中添加不同种类矿粉培养细菌,然后分别提取粗多糖和较纯多糖,发现矿物种类对胶质芽孢杆菌多糖的分泌有显著影响。添加含有细菌所需矿质养料的矿粉在培养液中,胞外多糖含量相对增高,说明细菌分泌胞外多糖受到矿物化学组成的影响,即细菌胞外多糖的产生与它们对矿物养料的需求和矿物的风化过程有密切联系。  相似文献   
48.
The Oligocene–Miocene carbonate record of the Zagros Mountains, known as the Asmari Formation, constitutes an important hydrocarbon reservoir in southern Iran. This marine carbonate succession, which developed under tropical conditions, is explored in terms of larger foraminiferal biostratigraphy, facies analysis and sequence stratigraphy in a new section at Papoon cropping out in the western Fars sub-basin, in the south-east of the Zagros belt. Facies analysis shows evidence of re-working and transport of skeletal components throughout the depositional system, interpreted here as a carbonate ramp. The foraminifera-based biozones identified include the Globigerina–Turborotalia cerroazulensis–Hantkenina Zone and Nummulites vascus–Nummulites fichteli Zone, both of Rupelian age, the Archaias asmaricus–Archaias hensoni–Miogypsinoides complanatus Zone of Chattian age and the ‘Indeterminate’ Zone of Aquitanian age. The vertical sedimentary evolution of the formation exhibits a progressive shallowing of the facies belts and thus the succession is interpreted as a high-rank low-order regressive systems tract. This long-lasting Rupelian–Aquitanian regressive event is in accordance with accepted global long-term eustatic curves. Accordingly, long-term eustatic trends would have been a factor controlling accommodation during the deposition of the Asmari Formation studied in the western Fars sub-basin.  相似文献   
49.
雄安新区在暂不考虑开采砂岩热储地热资源的前提下,探明碳酸盐岩热储东部边界断裂牛东断裂带的分布位置与地热资源品质,对新区地热资源开发利用规划的编制与整体能源利用布局均有着重要意义。以雄安新区高铁片区第一口碳酸盐岩热储勘探井D09孔的探测数据为依据,结合地震剖面解释成果,分析了牛东断裂带内碳酸盐岩热储的空间展布特征、储集层物理性质与单井产能参数,并简述其对地热勘探的指导意义。探测结果表明,牛东断裂带的碳酸盐岩热储主要为蓟县系雾迷山组含硅质的白云岩,分布在断裂西侧基岩宽缓背斜顶部,层状稳定,厚约2000m,顶板埋深1000~1200m,井口水温约70℃,单井水量约102m3/h。D09孔揭示,在距风化壳顶部678m的地层内共发育122个裂隙带,累计厚度达251.20m,裂隙发育率37%,平均孔隙度9.26%,裂隙发育率与平均孔隙度明显比断裂带外地热井高出50%。D09孔与牛东断裂带周缘地热井的地层地温梯度、地热水水化学特征、储集层导水系数等对比分析表明,垂直断距达7000m的牛东断裂带是一条导水导热的盆内隐伏型深断裂,其限定了雄安新区碳酸盐岩热储含水系统的东部边界,构成了西侧牛驼镇凸起的导水通道与东侧霸县凹陷油气运移的阻隔屏障,控制了牛驼镇凸起面积达1000km2的整装地热田的形成。  相似文献   
50.
Due to strong remodification and sparse trace remnants, tectonic restoration is critical for the reconstructing of the paleography and basin-prototype in the multiple-cycles superimposed basin, which is also fundamental for the hydrocarbon exploration of the deep marine carbonate in the Tarim Basin. This study presents the tectonic framework of the transition phase from the Sinian to the Cambrian Period and its constrains on the paleography of the Cambrian in the Tarim Basin based on comprehensive analysis of new geochronology data, seismic data and regional tectonic data. The results showed that (1) there is a large regional unconformity between the Cambrian and Precambrian, suggesting a discontinuous deposition from the Sinian to the Cambrian that is contrary to the major view; (2) a broad flattened paleotopography formed before Cambrian Period, which is favorable for the wide epicontinental sea environment and a gentle homoclinal ramp platform development in the early Cambrian, and the residual basement low relief uplifts that influence the microfacies differentiation in the carbonate platform; (3) the Cambrian carbonate platform has been involved much into the marginal orogenic belts, and the proto-platform is probably of 200 km out of the present basin in S-N direction; (4) there is a weak extensional setting in the Cambrian-Early Ordovician rather than a strong rifting setting with a large aulacogen into the platform, in which a inter-platform shallow depression and stable ramp platform developed in the Cambrian; (5) there is not troughs, but rather low relief uplifts developed in the Early Cambrian in the southwestern Tarim Basin, and lack of large uplifts along the carbonate platform margins; (6) it is showed a broad architecture of platform-wide slope-ocean basin from the inner Tarim plate to its margin in the Cambrian Period. Considering the basin prototype, the restoration of the tectono-paleography in the early Cambrian in the Tarim Basin is distinct from those of the previously proposed. We propose that a gentle pattern with “two platforms and one inter-depression” in E-W striking other than multiple small platform constrained in the basin, and further subdivision of the western platform with inner platform low uplift and sag in N-S striking, which is possibly inherited from the basement architecture. On the outer of the united platform, there is probably broad gentle slope for transition to ocean basin. We therefore argue that tectonic restoration is crucial for reconstruction of the paleogeography and basin prototype, especially for basins experienced multiphase of tectonic cycles. © 2018, Science Press. All right reserved.  相似文献   
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