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461.
碳酸盐岩中缝合线的形成机制及其储集意义讨论   总被引:17,自引:0,他引:17  
李国蓉 《矿物岩石》1997,17(2):49-54
本文以鄂尔多斯盆地马家沟组灰岩中发育的缝合线为研究对象,通过岩石学观察,阴极发光、电子探针、质谱分析资料的综合分析,对该套地层中的缝合线进行了分期分类,进而讨论了缝合线的形成机制和储集意义,建立缝合线形成与构造裂缝充填相联系的配套模式,并讨论了缝合线的演化及其向储渗空间转化特征,指出在一定条件下其对储层的形成及储集性的改善具较为重要的意义  相似文献   
462.
灰岩溶洞区桩基处理实例   总被引:5,自引:0,他引:5  
通过工程实例,介绍利用注浆法处理位于灰岩溶洞区桩基的成功经验,分析注浆加固桩基的基本原理,对其他类似工程提供设计和施工建议。  相似文献   
463.
随着火电厂二氧化硫烟气治理工程的陆续开展,需要大量的石灰石作为脱硫剂,目前,我国尚未制定脱硫石灰岩的工业指标,本文就脱硫技术及对石灰岩的质量要求进行了介绍,并针对贵州某电厂脱硫石灰岩的工业指标进行了初步探讨。  相似文献   
464.
井下钻孔注浆治理奥灰水技术   总被引:3,自引:1,他引:3  
肥城矿区水文地质条件极其复杂,奥灰水水位高,水量大,严重制约着煤矿开采的正常进行。通过肥城矿区井下施工奥灰孔进行奥灰水治理的经验及技术,认为井下施工奥灰孔,建立井下水文观测网以及对奥灰表层进行注浆改造,是行之有效的防治奥灰水的途径。  相似文献   
465.
奥 陶 系石 灰 岩 是 济宁 煤 田 一 区太 原 组 下 部煤 层 底 板 充水 含 水 层 ,岩 溶 裂隙 发 育 ,富 水 性 较 强,由 于排 泄 条 件差, 天然 状 态下 水质 不 符合 饮用 水标 准 。通 过 群孔 抽 水 试 验,改 变 了地 下 水 的 循环 条 件 ,使 水 质 达 到了 生 活 用 水 导致标 准,为此 区 奥灰 水的 综 合利 用打 下 了基 础。  相似文献   
466.
A database of ground vibration due to blasting at 27 limestone quarries, located in various parts of India, has been created. The database contains peak particle velocity (PPV), frequency, other vibration related and blast design parameters. Regression analysis of the data is carried out to derive site constants of the USBM predictor equation for individual quarries. It is found that these site constants are correlated with each other. By combining all the data, a generalised predictor equation is developed to assess and control ground vibration. In addition, mean zone of attenuation has been delineated using the predictor equations of the individual quarries. The dominant frequency of ground vibration with respect to distance and the possibility of modifying it by changing delay intervals in production blasts are also examined.  相似文献   
467.
This paper deals with a significant process of decohesion of a marly limestone, taking place in the cloister of the medieval Cathedral of Cefalù, a pleasant town on the northern coast of Sicily. After desalination with deionised water and consolidation with ethyl silicate, the decay of the stone became faster. The aim of our study is to characterise the stony material and investigate the observed decay phenomena. The stone, that is a poor building material indeed, is characterised by means of petrographical, chemical and physical analyses on samples taken from the monument. Furthermore, experimental tests are performed in the laboratory in order to highlight the causes of incompatibility between the stone and the applied treatments.  相似文献   
468.
A statistical, rule-based algorithm for generating fracture patterns similar to those observed in Limestone is presented. For each fracture set, initial seed points are randomly positioned within the modelled domain with the same density as the fractures observed in the field. An orientation is associated with each point by sampling from the distribution of orientations for the corresponding fracture set. Fractures are then allowed to grow from the seed points in both directions with this orientation until they meet other fractures whereupon they continue or terminate according to a fixed probability. A mathematical analysis of this method is presented for the case in which fractures within a set are assumed to be parallel. Approximations to the distribution of semi-trace lengths are derived which are shown to be in good agreement with simulation results. Fracture spacing distributions are also derived for this case.  相似文献   
469.
Treatment of the seepage problems at the Kalecik Dam (Turkey)   总被引:10,自引:0,他引:10  
Sedat Turkmen   《Engineering Geology》2003,68(3-4):159-169
This paper describes the seepage prevention measures at Kalecik Dam. Water leaked from the foundation of the dam after the impoundment. The dam, 77 m in height, was constructed for irrigation purposes.

The foundation consists of Mesozoic ophiolite, Paleocene allochthonous units composed of different lithologies and Miocene conglomerate. Karstified and fractured Paleocene limestone outcrops on the right bank of the dam foundation. This unit extends into, and its thickness increases within, the right abutment. The leakage occurs towards the downstream springs through the right bank limestone.

The main grout curtain is 200 m long and 60 m deep and was constructed on the right bank. After reservoir impounding, new springs were observed in the downstream area. Therefore, after the construction of the dam, remedial curtain grouting was required and carried out in three stages. Firstly, the main grout curtain was supplemented by additional grouting to seal the fractures and infill karstic cavities. The diversion tunnel was also repaired. The curtain depth was the same as the depth of the previous curtain. The second stage of additional treatment consisted of new deep grouting. Some investigation holes were also drilled along the same alignment as the main curtain to locate the seepage in the region. These holes were extended to an elevation of 442 m. The final stage of grouting measures was between the spillway and the dam body and underneath the spillway.

As a result of the additional grouting measures, the spring discharges observed downstream of the dam embankment decreased. However, the seepage paths were extended and were moved with time so that the seepage problems are still continuing.  相似文献   

470.
本溪水洞位于上马家沟组砾屑灰岩中。洞穴的形成主要受北西向断裂构造控制,当时的古气候、古地貌以及水文地质条件是其形成的重要因素。水洞形成于中-晚更新世。  相似文献   
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