宜昌老林沟石榴石矿床地质特征     

刘云勇 《化工矿产地质》2004,26(1):23-28

老林沟石榴石矿产于黄陵背斜北部类孔兹岩系中一套富铝铁质正常沉积的泥质粉砂岩、泥质岩中,在区域热动力变质作用下,铁铝榴石与夕线石共生,属于巴罗变质系列中夕线石带产物,根据矿物共生组合、指相特征矿物得出形成该矿产的区域变质的温压条件为:t为7 00℃,P为7 30MPa,变质相属低角闪岩相至高角闪岩相。  相似文献   

花岗岩类源岩与深部地质作用关系研究的若干进展   总被引：1，自引：0，他引：1  

邱瑞照  彭松柏 《湖南地质》1998,17(4):276-279

花岗岩类源岩研究是成岩成矿物质演化过程研究的基础,各种各样花岗岩的存在归因于花岗岩源岩存在多样性,在不同层圈发生交代,熔融,同化,混染作用;同时,成矿元素亦存在不同深度层圈的多来源,在花岗岩成岩成矿过程中,岩石圈地幔起着重要作用。  相似文献   

Efficiency of a re-usable Carius tube for determination of platinum group elements in ultramafic rocks     

Yingying Liu  Liang Qi  Zheng Zhao  Xiaowen Huang  Yichang Wang 《中国地球化学学报》2014,33(1):45-52

Digestion with aqua regia in Carius tube is commonly employed for determination of PGEs in geological samples. However, silicates cannot be completely dissolved by aqua regia and PGEs might partially remain in silicate residue. In this study, an ultramafic reference material was used to investigate the efficiencies of a new re-usable Carius tube after digestion at 220 and 240℃, and an autoclave-lined Carius tube at 260 and 280℃. The results show that about 10% of PGEs retained in the silicate residues at 220 and 5% still r℃ emains even digestion temperature increases to 280℃. These results agree with previous works that increasing the digestion pressure and temperature can achieve more effective dissolution. Thus, a modified digestion procedure for determination of PGEs in ultramafic rocks by the re-usable Carius tube was proposed in this study.  相似文献   

Changes in temperature extremes based on a 6-hourly dataset in China from 1961–2005     

胡宜昌  何勇  董文杰 《大气科学进展》2009,26(6):1215-1225

Changes in Chinese temperature extremes are presented based on a six-hourly surface air temperature dataset for the period 1961--2005. These temperature series are manually observed at 0200, 0800, 1400, and 2000 Beijing Time (LST), and percentile based extreme indices of these time series are chosen for analysis. Although there is a difference in time among the different time zones across China, as more than 80% of the stations are located in two adjacent time zones, these indices for all the stations are called warm (cold) nights (0200 LST), warm (cold) mornings (0800 LST), warm (cold) days (1400 LST), and warm (cold) evenings (2000 LST), respectively for convenience. The frequency of the annual warm extremes has generally increased, while the frequency of the annual cold extremes has decreased, and significant changes are mainly observed in northern China, the Tibetan Plateau, and the southernmost part of China. Based on the national average, annual warm (cold) nights increase (decrease) at a rate of 5.66 (-5.92) d (10 yr)^-1, annual warm (cold) days increase (decrease) at a rate of 3.97 (-2.98) d (10 yr)^-1, and the trends for the annual warm (cold) mornings and evenings are 4.35 (-4.96) and 5.95 (-4.35) d (10 yr)^-1, respectively. For China as a whole, the increasing rates for the occurrence of seasonal warm extremes are larger in the nighttime (0200, 2000 LST) than these in the daytime (0800, 1400 LST), the maximal increase occurs at 2000 LST except in the summer and the minimal increase occurs at 1400 LST except in autumn; the maximal decrease in the occurrence of seasonal cold extremes occurs at 0200 LST and the minimal decrease occurs at 1400 LST.  相似文献   

伊拉克H油田Mishrif组生物碎屑类型及对储层物性的控制作用     

余义常  宋新民  郭睿  林敏捷  衣丽萍  李峰峰  刘航宇 《地质论评》2019,65(Z1):263-264

正白垩系Mishrif组生物碎屑灰岩是伊拉克H油田的重要产层,生物碎屑主要是有壳类碎屑(田泽普等,2016;王昱翔等,2017)。由于缺乏各类生物碎屑成分及成岩过程中的差异性分析,对生物碎屑灰岩储层物性的控制机理研究不够深入,限制了对该类储层的认识及高效开发。本文基于岩心观察、铸体薄片及常规物性等资料,开展伊拉克H油田Mishrif组的生物碎屑类型、成岩特征及储层物  相似文献   

多因素自主低渗透储层分类方法     

李峰峰  郭睿  余义常  李军 《地质论评》2019,65(Z1):155-156

正低渗透储层成因机理复杂、开发稳定性低、油气分布及渗流特征等具有一定的特殊性,国内学者建立了众多低渗透储层分类方法,不同方法的分类标准存在差异(杨正明等,2006;杨秋莲等,2007;胡文瑞,2009;张仲宏等,2012)。埕北低断阶位于黄骅坳陷埕宁隆起与歧口凹陷之间的低位坡折带,储层多为超低渗、特低渗及致密型储层,现有储层分类标准区分性较差,适应性较低。基于沙二  相似文献   

中国南部早石炭世聚煤期、聚煤区及有关含煤地层的划分与对比     

许寿永  叶干 《地质论评》1992,38(3)

华南下石炭统为中国南部地区的主要含煤地层之一。据其聚煤期的先后、含煤性及其工业可采煤层等不同因素,划分为Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ聚煤期及8个聚煤区,并对有关存在争议地层的时空关系和化石带作了阐明。  相似文献   

三峡地区震旦系碳酸盐岩碳氧同位素特征   总被引：17，自引：0，他引：17  

陈孝红  李华芹等 《地质论评》2003,49(1):66-73

本文对三峡地区秭归庙河陡山沱组第一段至第三段，宜昌棺材崖陡山沱组第三段上部至灯影组底部以及四溪灯影组石板滩段和白马沱段碳酸盐岩碳氧同位素组成特点的研究结果表明，三峡地区震旦系碳同位素组成与全球新元古代广布的后Martinoan冰期地层δ^13C的分布模式基本一致，本文还讨论了地层中碳同位素组成与生物演化和地层层序发展的关系，指出陡山沱组一段白云岩中δ^13C的负异常可以作为震旦系底界划分的标志，最晚Varanger冰期在三峡地区由陡山沱组三段上部出现的三级层序界面所替代，震旦系内部陡山沱组一段和三段可能形成于Marinoan冰期之后，伊迪卡拉生物分异发展之前，而陡山沱组四段及上覆灯影峡组则大致与国外伊迪卡拉期地层对比。  相似文献   

New Chronological Evidence for Indosinian Diagenetic Mineralization in Eastern Xinjiang, NW China   总被引：7，自引：2，他引：7  

LI Huaqin  CHEN Fuwen  LU Yuanf  YANG Hongmei  GUO Jing  MEI Yuping Yichang Institute of Geology  Mineral Resources  Gangyao Ro  Yichang  Hubei 《《地质学报》英文版》2005,79(2):264-275

1 IntroductionMineralization in E. Xinjiang constitutes an importantpart of the Mid-Asian Metallogenetic Province. A greatdeal of nonferrous, ferrous, rare and noble metaldeposits of different genetic types and ages were formedduring different crustal evolution stages and werecontrolled by regional tectonic evolution. Large-scalemineralization of metallic deposits and relatedmagmatism mainly occurred during the Carboniferous toPermian periods (Li et al., 1998; Ji et al., 1999; Mao etal., 2…  相似文献   

桂东北牛庙闪长岩和同安石英二长岩:岩石学、锆石SHRIMP U-Pb年代学和地球化学   总被引：12，自引：4，他引：12  

朱金初谢才富  张佩华杨策　顾晟彦 《岩石学报》2005,21(3):665-676

桂东北牛庙和同安岩体分别由闪长岩和石英二长岩组成。锆石的SHRIMP U-Pb年龄分别为163±4Ma和160± 4Ma。岩石以富铝、富碱、高钾、富含Rb、Ba、Th、U、Pb、Sr等大离子半径亲石元素(LILE)及富含REE、Nb、Ta、Zr、Hf等高场强元素(HFSE)为主要特征,属富钾系列或钾玄岩系列。其不相容元素的分布特征为亲OIB型,主要来源于富集的岩石圈地幔的熔融。两岩体的常量元素、微量元素和Sr-Nd同位素组成特征,反映了它们的原始岩浆经历过相当充分的分离结晶和相当程度的地壳混染,即通过AFC方式而形成。岩体中广泛分布的微细粒状暗色包体是共存的更偏基性的岩浆与寄主岩浆不完全混合的残留,其成分的多样性和相互过渡关系,反映了不同包体母岩浆在形成和演化途径等方面的差异性。岩体形成于燕山早期华南后造山阶段大陆地壳拉张减薄的构造环境,软流圈地幔沿超岩石圈深断裂的上涌和底侵,是造成富集的岩石圈地幔和中下地壳熔融并形成本区闪长质和花岗质岩浆的主要机制。  相似文献