聚合物钻井液在河北广宗勘探区深孔施工中的应用     

孙贵生 《中国煤炭地质》2014,(6):71-73

在河北广宗勘探区深孔施工中,由于地表钻探用水水质影响及原钻井液体系不合适,造成钻井液性能指标达不到要求,性能难以控制,尤其失水量严重超标,接连发生孔内事故。针对存在的问题,经过分析和实验,采用化学方法处理钻探用水,选用聚合物钻井液,解决了深部钻孔施工存在的难点,收到了较好的效果,单孔深度达到1937.35m,并刷新了本单位及局属单位的钻探记录。  相似文献   

Application of rock mass index (RMi) to the rock mass excavatability assessment in open face excavations     

Mashallah Khamehchiyan  Morteza Rahimi Dizadji  Majid Esmaeili 《Geomechanics and Geoengineering》2014,9(1):63-71

Earthwork and surface excavation activities play an important role in construction projects. Selecting the best technique to loosen the overburden material within the surface excavation in open mining and geotechnical projects is of great importance from economical and technical viewpoints. Surface excavation includes direct digging, ripping and blasting. To select the most effective method and plan for excavation, geotechnical investigation is very important. It is also a big help in avoiding conflict between contractors and clients when they do not reach mutual agreement regarding the price of rock and soil excavation. There are many engineering classification systems used to assess rock masses for excavation purposes. All of these systems consider several geotechnical parameters to assess the earth masses. This study reviews these systems and then offers a new categorization based on the Rock Mass index (RMi) classification system and block volume to assess excavation in rock masses. The original dataset was obtained from the literature review as well as the surface excavation in Upper Gotvand dam and Hydro Power Plant (HPP). The offered system was also validated through the data extracted from the surface excavation in Sardasht dam and HPP in Iran.  相似文献   

山西吕梁山北段中生代构造特征及对成矿的制约          下载免费PDF全文

孙思磊  张兆琪 《中国地质调查》2014,6(3):56-62

为进一步研究山西吕梁山北段中生代构造特征及对成矿的制约,利用数字化填图方法,在偏关县一带开展1:25万区域地质调查。发现几条中生代大型构造带,查明了这些大型构造带的空间展布、性质、断裂组合及运动学特征; 证实了中生代为该区重要的多金属成矿期,成矿作用尽管与中生代岩浆活动关系密切,但在空间上分布受NE向隐伏构造的制约; 大型挠褶构造是地壳强烈隆升的标志,区内大型构造带多数是在挠褶构造的基础上叠加断层而形成的。该研究对于探讨山西中—新生代构造的演化发展具有重要意义。  相似文献   

Hydrofracturing in response to the development of an overpressurised subglacial meltwater system during drumlin formation: an example from Anglesey,NW Wales     

Emrys Phillips  Leanne Hughes 《Proceedings of the Geologists' Association. Geologists' Association》2014

This paper presents the results of a detailed study of a complex hydrofracture system and host diamictons exposed within a longitudinal section through an elongate drumlin located to the west of Cemlyn Bay, Anglesey, NW Wales. This complex, laterally extensive sand, silt and clay filled hydrofracture system was active over a prolonged period and is thought to have developed beneath the Late Devensian (Weichselian) Irish Sea Ice Stream as it overrode this part of NW Anglesey. The sediment-fill to the hydrofracture system is deformed with kinematic indicators (folds, thrusts, augen) recording a SW-directed sense of shear, consistent with the regional ice flow direction across this part of the island. The lack of any geomorphological evidence for active retreat of the Irish Sea ice across Anglesey has led to the conclusion that hydrofracturing at the Cemlyn Bay site occurred within the bed of the Irish Sea Ice Stream whilst this relatively faster flowing corridor of ice was actively overriding the island. Shear imposed by the overriding ice led to the development of a subglacial shear zone which facilitated the propagation of the hydrofracture system with the laterally extensive feeder sills occurring parallel to Y-type Riedel shears. Although a subglacial setting beneath the active Irish Sea Ice Stream can be argued for the Cemlyn Bay hydrofracture system, its relationship to the formation of the ‘host’ drumlin remains uncertain. However, evidence presented here suggests that hydrofracturing may have occurred during the later stages or post landform development in response to the migration of overpressurised meltwater within the bed of the Irish Sea ice; possibly accompanying the local thinning and shutdown of the Irish Sea Ice Stream on Anglesey.  相似文献   

A 2000-yr reconstruction of air temperature in the Great Basin of the United States with specific reference to the Medieval Climatic Anomaly   总被引：1，自引：0，他引：1  

Scott A. Reinemann  David F. Porinchu  Glen M. MacDonald  Bryan G. Mark  James Q. DeGrand 《Quaternary Research》2014

A sediment core representing the past two millennia was recovered from Stella Lake in the Snake Range of the central Great Basin in Nevada. The core was analyzed for sub-fossil chironomids and sediment organic content. A quantitative reconstruction of mean July air temperature (MJAT) was developed using a regional training set and a chironomid-based WA-PLS inference model (r²_jack = 0.55, RMSEP = 0.9°C). The chironomid-based MJAT reconstruction suggests that the interval between AD 900 and AD 1300, corresponding to the Medieval Climate Anomaly (MCA), was characterized by MJAT elevated 1.0°C above the subsequent Little Ice Age (LIA), but likely not as warm as recent conditions. Comparison of the Stella Lake temperature reconstruction to previously published paleoclimate records from this region indicates that the temperature fluctuations inferred to have occurred at Stella Lake between AD 900 and AD 1300 correspond to regional records documenting hydroclimate variability during the MCA interval. The Stella Lake record provides evidence that elevated summer temperature contributed to the increased aridity that characterized the western United States during the MCA.  相似文献   

新疆阿克陶县有色矿石的非金属元素成分分析     

阿里木江&#;艾拜都拉  程春英 《岩矿测试》2014,33(1):44-50

岩矿测试和分析更多关注矿石矿物中的金属离子,但其中阴离子及其存在形式的研究对于理解矿石的组成、成因和金属离子的存在状态具有重要意义。本文采用红外光谱、X射线电子能谱和热重分析等方法对新疆阿克陶县奥依塔克镇的有色矿石中非金属元素进行成分分析。研究结果表明,矿石含有H、C、O、Si等非金属元素,主要以—C—O、C═O、Si—O—C和Si—O阴离子的形式存在,并与Mg、Al、Ca等主要金属元素形成γ-Al2O3、CaO·SiO2、MgCO3、CaCO3等化合物。样品煅烧到900℃,导致样品损失水分并使其中的MgCO3发生分解,而CaCO3不分解,分解产生的MgO与Si—O结合生成MgO·SiO2,表明矿石主要含有碳酸盐和硅酸盐,是具有白云石矿石特性的混合型矿石。  相似文献   

Mammalian femora across the Cretaceous–Paleogene boundary in eastern Montana     

《Cretaceous Research》2014

Our understanding of latest Cretaceous and earliest Paleogene mammalian evolution is based almost entirely on the dental fossil record. Mammalian postcranial fossils are rare and mostly found as isolated elements in latest Cretaceous and earliest Paleogene vertebrate microfossil assemblages of North America. Although placing these fossils in a tooth-based taxonomic framework is difficult, they can provide insight into locomotor diversity and habitat preference to complement diet reconstructions and diversity estimates from dental fossils. Here, we describe 64 femora of mammals recovered from latest Cretaceous (Lancian) and earliest Paleogene (Puercan) localities in eastern Montana. We sorted these based on morphology and size (morphotypes). In some cases, morphotypes were tentatively assigned to dentally based taxa that are known from these strata.Although our resulting femoral dataset is small relative to the study area's dental dataset, we show several key findings. First, there is a greater morphological diversity of multituberculate femora than previously recognized, especially in the latest Cretaceous sample. In contrast, metatherians, which have a high relative abundance in Lancian Hell Creek Formation dental assemblages, are absent from our postcranial samples; eutherian femora are only present in the Puercan assemblages. Second, we record a minor decrease in morphotype richness across the K–Pg boundary that is associated with an increase in mean specimen size, due to the appearance of a few significantly larger-bodied, immigrant taxa. Among the eutherians, there are two specimens of larger-bodied early Puercan archaic ungulates, a very large specimen of a middle/late Puercan taeniodont, pantodont, or triisodontid, as well as a specimen possibly attributed to a “plesiadapiform” archaic primate. Third, preliminary functional morphologic analyses of the more complete specimens suggest that locomotor diversity increased from mainly arboreal or terrestrial/saltatorial multituberculates in the latest Cretaceous to include a fossorial multituberculate and potentially an arboreal eutherian in the early Paleocene. These patterns parallel those previously reported from a dental dataset and indicate that postcranial data are valuable as an independent means to test hypotheses of taxonomic and ecomorphological diversity across the K–Pg boundary.  相似文献   

塔里木盆地西南部麦盖提斜坡构造演化过程的 记录——生长地层及生长不整合   总被引：2，自引：0，他引：2  

吕明  汤良杰  岳勇 《地质论评》2014,60(1):91-101

根据塔里木盆地西南部麦盖提斜坡生长地层的发育模式,并结合不整合类型及发育特征的变化规律,探讨了麦盖提斜坡的构造演化过程。认为在早古生代时期,麦盖提斜坡为一北倾的斜坡,构造高点位于斜坡南部;晚古生代,麦盖提斜坡的构造演化过程具有明显的分段性,斜坡西段主要的构造演化时期始于早石炭世,并持续至早二叠世,构造高点迁移至斜坡中部,呈现出"中间高、两头低"的古构造特征;而斜坡东段的主要构造演化时期推迟至晚二叠世。新生代,麦盖提斜坡已反转为南倾的斜坡,构造高点已迁移至斜坡北部,斜坡东段从前中新世开始进入构造演化时期,而西段则推迟至中新世,且东段的构造活动强度要大于西段。  相似文献   

红层“哑地层”划分对比方法——以东营凹陷南坡始新统为例   总被引：1，自引：0，他引：1  

刘书会  高永进  王长轩 《地质论评》2014,60(5):1043-1050

针对红层划分对比所面临的难题,在充分吸收前人研究成果的基础上,将现有的多种分层方法相互整合,彼此约束和印证,形成了一套科学、便捷的技术方法,即"接触关系明顶底、岩电特征找界面、多元融合定方案、地震约束建格架"的综合地层划分对比技术。该方法针对红层的特殊性,根据岩电特征对干旱气候的响应变化,充分利用了测、录井资料纵向上的连续性优势(避免了取样分析的局限),以及地震资料横向上的优势,有效地解决了红层纵向划分、横向对比的难题,在济阳坳陷东营凹陷南坡始新统沙河街组、孔店组的应用取得了良好效果。该方法可为其它地区同类复杂地层划分对比提供技术支持。  相似文献   

云南石林世界地质公园阿诗玛石柱碳酸盐岩 显微特征及沉积环境     

彭阳  陈安泽  钱方 《地质论评》2014,60(5):1109-1112

云南石林世界地质公园阿诗玛石柱,其岩石地层是呈水平产状的中二叠统茅口组厚层块状灰岩,但其构成岩石的具体岩性却未见做过详细工作。笔者等经公园管理部门同意,自下而上分别在阿诗玛石柱背侧底部、下部、中部、上部和顶部共采集样品五块,对其岩石学特征及沉积微相作了详细研究,弄清了这一世界著名景点自下而上的岩石构成及沉积相。底部为高能浅滩相灰色厚层块状具平行层理生屑颗粒灰岩,构成阿诗玛脚部。下部为中能浅潮下灰色厚层块状虫筳生屑泥粒灰岩,构成阿诗玛腿部。中部为中能浅潮下灰色厚层块状砂屑泥粒灰岩,构成阿诗玛腰部。上部为中能浅潮下灰色厚层块状具生物扰动含砂屑生屑泥粒灰岩,构成阿诗玛胸部;顶部为高能浅滩相灰色厚层块状砂屑生屑颗粒灰岩,构成阿诗玛头部。其中含有大量生物化石碎屑:有孔虫、三叶虫、藻类、介形虫、腕足、苔藓虫、虫筳、海百合茎、双壳类,为高能浅滩相和中等能量浅潮下环境。希能为石林形成过程研究和科学普及提供参考。  相似文献