矿井初步设计中边界防隔水煤岩柱留设探讨   总被引：1，自引：0，他引：1  

胡东祥  朱孔盛  侯家林 《中国煤炭地质》2011,(6):33-35,39

针对一些矿井初步设计中留设边界防隔水煤岩柱不合理而引发矿井老空水矿难的现实,探讨了影响矿井间边界防隔水煤岩柱安全稳定性的因素,提出应充分考虑煤岩柱受覆岩应力破坏变形、覆岩受采动影响产生岩移破坏等,综合分析计算煤柱有效稳定性弹性核区宽度、覆岩导水裂缝带上限岩柱宽度及其抗静水压能力等,择优选取留设矿井边界防隔水煤岩柱。以济宁煤田济宁二矿与三矿边界煤柱的留设为例,计算其边界煤柱留设尺寸为99.56m,较原设计的40m有较大出入,据此对两矿井边界隔离煤柱进行了相应调整,确保了矿井的安全生产。该方法也可用于矿井留设采区、区段隔离煤柱的计算。  相似文献   

Late Mesozoic Ore‐forming Events in the Ningwu Ore District,Middle‐Lower Yangtze River Polymetallic Ore Belt,East China: Evidence from Zircon U‐Pb Geochronology and Hf Isotopic Compositions of the Granodioritic Stocks   总被引：2，自引：0，他引：2  

DUAN Chao  LI Yanhe  HOU Kejun  YUAN Shun  LIU Jialin  ZHANG Cheng 《《地质学报》英文版》2012,86(3):719-736

Late Mesozoic volcanic-subvolcanic rocks and related iron deposits, known as porphyry iron deposits in China, are widespread in the Ningwu ore district (Cretaceous basin) of the middle–lower Yangtze River polymetallic ore belt, East China. Two types of Late Mesozoic magmatic rocks are exposed: one is dioritic rocks closely related to iron mineralization as the hosted rock, and the other one is granodioritic (-granitic) rocks that cut the ore bodies. To understand the age of the iron mineralization and the ore-forming event, detailed zircon U-Pb dating and Hf isotope measurement were performed on granodioritic stocks in the Washan, Gaocun-Nanshan, Dongshan and Heshangqiao iron deposits in the basin. Four emplacement and crystallization (typically for zircons) ages of granodioritic rocks were measured as 126.1±0.5 Ma, 126.8±0.5 Ma, 127.3±0.5 Ma and 126.3±0.4 Ma, respectively in these four deposits, with the LA-MC-ICP-MS zircon U-Pb method. Based on the above results combined with previous dating, it is inferred that the iron deposits in the Ningwu Cretaceous basin occurred in a very short period of 131–127 Ma. In situ zircon Hf compositions of εHf(t) of the granodiorite are mainly from ?3 to ?8 and their corresponding 176Hf/177Hf ratio are from 0.28245 to 0.28265, indicating similar characteristics of dioritic rocks in the basin. We infer that granodioritic rocks occurring in the Ningwu ore district have an original relationship with dioritic rocks. These new results provide significant evidence for further study of this ore district so as to understand the ore-forming event in the study area.  相似文献   

对流层投影函数对精密单点定位精度的影响分析     

李施佳  蔡昌盛  李佳霖  易志鹏 《全球定位系统》2013,(5):22-26

对流层延迟误差是GPS定位中的一项重要的误差源,随着精密单点定位（PPP）技术的不断发展,该误差影响并制约着GPS精密单点定位精度的进一步提高。基于GPS观测值,比较分析了各种对流层投影函数模型对GPS精密单点定位精度的影响,得出了有益的结论。  相似文献   

顾及时空异质性的缺失数据时空插值方法     

樊子德  龚健雅  刘博  李佳霖  邓敏 《测绘学报》2016,45(4):458-465

时空插值方法被广泛应用于缺失时空数据集的插值与估计。时空插值是时空建模与分析的一个重要内容,当前该研究关注的热点之一是异质条件下的时空插值与估计问题。因此,本文从时空数据的异质性出发,提出了一种顾及时空异质性的缺失数据时空插值方法。该方法首先对数据集进行时空分区,然后分别在时间和空间按照异质协方差模型计算缺失数据的估计值,进而利用相关系数确定时空权重、融合时间和空间估计值得到缺失数据的最终估计结果。最后通过两组气象数据集进行交叉验证对比分析试验。试验结果表明本文方法对比其他插值方法具有更高的精度和适用性。  相似文献   

行业动态信息采集系统关键问题解决方案     

黎柯  蔡永香  干佳林  王居远  杨鼎  胡森勇 《测绘科学》2016,41(3):161-166

为了解决行业动态信息采集系统中网页定向爬取、网页清洗、信息检索等关键问题,文章提出一套基于Heritrix、Jsoup和Lucene的解决方案,并以测绘地理动态信息系统为例进行验证,结果证明该方法能够较好完成测绘地理信息的定向爬取,实现对不同风格网站网页的清洗,并建立索引提供信息检索机制,给测绘行业人士提供准确可靠的信息服务,为相关研究提供参考。  相似文献   

Geochronological Framework and Geodynamic Implications of Mafic Magmatism in the Liaodong Peninsula and Adjacent Regions, North China Craton   总被引：2，自引：0，他引：2  

LI Zhuang  CHEN Bin  WANG Jialin 《《地质学报》英文版》2016,90(1):138-153

Mafic rocks are widespread on the Liaodong Peninsula and adjacent regions of the North China Craton. The majority of this magmatism was originally thought to have occurred during the Pre-Sinian, although the precise geochronological framework of this magmatism was unclear. Here, we present the results of more than 60 U–Pb analyses of samples performed over the past decade, with the aim of determining the spatial and temporal distribution of mafic magmatism in this area. These data indicate that Paleoproterozoic–Mesoproterozoic mafic rocks are not as widely distributed as previously thought. The combined geochronological data enabled the subdivision of the mafic magmatism into six episodes that occurred during the middle Paleoproterozoic, the late Paleoproterozoic, the Mesoproterozoic, the Late Triassic, the Middle Jurassic, and the Early Cretaceous. The middle Paleoproterozoic (2.1–2.2 Ga) mafic rocks formed in a subduction-related setting and were subsequently metamorphosed during a ca. 1.9 Ga arc–continent collision event. The late Paleoproterozoic (ca. 1.87–1.82 Ga) bimodal igneous rocks mark the end of a Paleoproterozoic tectono-thermal event, whereas Mesoproterozoic mafic dike swarms record global-scale Mesoproterozoic rifting associated with the final breakup of the Columbia supercontinent. The Late Triassic mafic magmatism is part of a Late Triassic magmatic belt that was generated by post-collisional extension. The Middle Jurassic mafic dikes formed in a compressive tectonic setting, and the Early Cretaceous bimodal igneous rocks formed in an extensional setting similar to a back-arc basin. These latter two periods of magmatism were possibly related to subduction of the Paleo-Pacific plate.  相似文献   

鄂尔多斯盆地志丹地区安定组泥灰岩地球化学特征及古环境意义     

汤超  肖鹏  魏佳林  徐增连  刘华健  赵丽君 《地质学报》2021,95(8):2537-2552

通过对鄂尔多斯盆地志丹地区安定组顶部泥灰岩系统的岩石学和地球化学分析,研究了安定组沉积末期湖盆的古盐度、氧化还原环境、古气候及物源区背景.结果表明:安定组泥灰岩主要由方解石和白云石组成,其中方解石含量26.5％～68.5％,平均42.5％,白云石含量10.1％～40.5％,平均25.3％;岩石具有较高的Sr丰度、Sr/Ba比值,指示沉积时水体盐度较高;碳氧同位素变化范围不大,δ13 CPDB为-3.5‰～2.2‰,平均0.55‰,δ18OPDB为-6‰～-1.2‰,平均-3.87‰,接近咸水湖碳酸盐沉积物,Z值范围为119.53～130.01,平均为126.51,显示安定组泥灰岩段形成于湖水咸化期;化学蚀变指数CIA及Sr/Cu、SiO2/Al2O3综合指示泥灰岩的物源区所受化学风化并不强烈,沉积于半干旱炎热的气候;氧化还原环境指标V/Cr、V/(V+Ni)比值及敏感金属元素U、Mo高度富集等特征指示泥灰岩沉积时的古水体条件整体处于还原环境;La/Yb-∑REE和La/Sc-Co/Th源岩属性判别图解显示泥灰岩主要沉积物源以长英质岩石为主,并混合有中-基性岩浆岩,与鄂尔多斯盆地北部阴山地区的古元古代变质岩系具有一定的亲源性.安定组末期半干旱炎热的气候条件,有利于蚀源区铀元素的活化迁移和含氧含铀流体形成和湖盆中铀的原始富集沉淀,为鄂尔多斯盆地大规模砂岩型铀成矿作用提供了重要条件.  相似文献   

自然资源部政务网站建设研究与实践     

陈卉  叶兴茂  杨征  程立海  李佳临 《地理信息世界》2022,29(2):52-56

自然资源部政务网站是部机关办公的总门户,数据集成和共享的总平台.根据多年的网站建设和管理经验,本文基于网站系统架构和内容管理系统功能设计,结合网站建设思路,阐述网站的内容体系建设,构建一套完善的网站维护和管理模式,介绍人员权限管理模式、办公自动化业务系统及视频系统集成模式、检索查阅模式的技术实现方法,可为国家行政机关政...  相似文献   

入侵冷空气强度对台风变性过程的影响   总被引：7，自引：4，他引：3  

陆佳麟  郭品文 《气象科学》2012,32(4):355-364

利用WRF中尺度模式对0716号"罗莎"台风的变性过程进行数值试验研究,讨论不同强度的入侵冷空气对台风变性过程的影响,结果表明适当强度冷空气入侵有利于斜压能的积累和释放,是导致台风变性的重要因素,而太强或太弱的冷空气都不利于台风的变性加强。当冷空气减弱时,台风登陆后边界层的热量通量减少,在没有新的能量供给的情况下,台风由于边界层摩擦作用和水汽供应不足而逐渐消散;当入侵冷空气过强时,台风内部会被迅速填塞,暖心变为冷心,从而逐渐消散。  相似文献   

Construction of ecological security patterns and ecological restoration zones in the city of Ningbo,China     

Zhang  Haitao  Li  Jialin  Tian  Peng  Pu  Ruiliang  Cao  Luodan 《地理学报(英文版)》2022,32(4):663-681

Journal of Geographical Sciences - Studying an ecological restoration zoning process under the background of ecological security patterns is of great significance to the rapid adjustment and...  相似文献