“十五”期间福建区域数字强震观测系统建设     

陈文明  史粦华 《福建地震》2003,(1)

本文介绍十五期间福建省将要实施建设的数字强震观测台网 ,着重从项目的必要性和方案的可行性方面进行论述 ,同时结合福建省的地震监测台网现状进行系统的设计。力求建成的强震观测系统能初步实现福建省属重点城市的地震烈度速报及典型场地强地震动记录获取双重功能 ,增强福建省的地震监测能力 ,为福建省地震灾害的减轻、有效救灾措施的实施以及防震减灾规划的制定提供基础依据 ;同时 ,也将为其他省市区域数字强震观测台网的建立提供示范样板  相似文献   

甘肃省非金属矿产资源开发利用前景   总被引：1，自引：0，他引：1       下载免费PDF全文

张翔  苏建平  雒晓刚 《甘肃地质》2003,12(2):62-66

本文介绍了甘肃省非金属矿的特点及开发利用现状,根据非金属矿业发展趋势及甘肃资源特征分析了开发利用前景,提出了发展对策。  相似文献   

Late Quaternary climatic control on erosion and weathering in the eastern Tibetan Plateau and the Mekong Basin     

Zhifei Liu  Christophe Colin  Alain Trentesaux  Giuseppe Siani  Norbert Frank  Dominique Blamart  Segueni Farid 《Quaternary Research》2005,63(3):769-328

High-resolution siliciclastic grain size and bulk mineralogy combined with clay mineralogy, rubidium, strontium, and neodymium isotopes of Core MD01-2393 collected off the Mekong River estuary in the southwestern South China Sea reveals a monsoon-controlled chemical weathering and physical erosion history during the last 190,000 yr in the eastern Tibetan Plateau and the Mekong Basin. The ranges of isotopic composition are limited throughout sedimentary records: ⁸⁷Sr/⁸⁶Sr = 0.7206–0.7240 and ε_Nd(0) = −11.1 to −12.1. These values match well to those of Mekong River sediments and they are considered to reflect this source region. Smectites/(illite + chlorite) and smectites/kaolinite ratios are used as indices of chemical weathering rates, whereas the bulk kaolinite/quartz ratio is used as an index of physical erosion rates in the eastern Tibetan Plateau and the Mekong Basin. Furthermore, the 2.5–6.5 μm/15–55 μm siliciclastic grain size population ratio represents the intensity of sediment discharge of the Mekong River and, in turn, the East Asian summer monsoon intensity. Strengthened chemical weathering corresponds to increased sediment discharge and weakened physical erosion during interglacial periods. In contrast, weakened chemical weathering associated with reduced sediment discharge and intensified physical erosion during glacial periods. Such strong glacial–interglacial correlations between chemical weathering/erosion and sediment discharge imply the monsoon-controlled weathering and erosion.  相似文献   

Geochemical research on C-O and Sr-Nd isotopes of mantle-derived rocks from Shandong Province, China   总被引：3，自引：0，他引：3  

LIU Jianming  ZHANG Hongfu  SUN Jinggui & YE Jie. Institute of Geology  Geophysics  Chinese Academy of Sciences  Beijing  China  . School of Earth Science  Jilin University  Changchun  China Correspondence should be addressed to Liu Jianming 《中国科学D辑(英文版)》2004,47(2)

Abstract This paper presents systematic studies on the C-O and Sr-Nd isotopic compositions for Cretaceous Badou carbonatites, Fangcheng basalts, and Jiaodong lamprophyres and Paleozoic Mengyin kimberlites in Shandong Province, China. Paleozoic kimberlites have normal and uniform C-O isotopic compositions with δ13C and δ18O in the range of-4.8‰-7.6‰ and +9.9‰-+13.2‰, respectively. However, Cretaceous three different types of mantle-derived rocks have quite different C-O isotopic compositions, indicating that the mantle sources are probably partially contaminated with organic carbon-bearing crustal materials. These Cretaceous rocks show uniform and EMII-like Sr-Nd isotopic compositions and also indicate that the mantle sources were affected by recycled crustal materials. Comparative studies of C-O and Sr-Nd isotopes reveal that the lithospheric mantle beneath the eastern North China Craton had different isotope characteristics in the Paleozoic, the early Cretaceous, and the Tertiary time. This demon  相似文献   

中国北方元古宙沉积岩中自生稀土矿物特征及其意义--以北京、大连地区为例   总被引：4，自引：0，他引：4  

宋天锐  万渝生  陈振宇  张巧大 《地质学报》2004,78(6):822-828

大连震旦系十三里台组首次发现自生稀土元素矿物独居石后 ,在北京十三陵中元古代长城系常州沟组、串岭沟组和大红峪组又发现了自生的独居石以及其他磷酸盐和硅酸盐稀土矿物。自生稀土矿物的形成和岩石中稀土元素含量较高有关 ;电子探针背散射图像和 P、Th、L a、Ce、Nd、Y等元素面分布图像研究表明 ,沉积岩中的自生稀土矿物与岩浆岩、变质岩和碎屑成因的截然不同。本文首次报道了元古宙长城系常州沟组沉积岩中碎屑锆石边部成岩过程中形成的自生磷钇矿。中国北方元古宙泥砂质碎屑沉积岩普遍具有高稀土组合 ,许多地区都可能存在独居石等自生稀土矿物 ,如天津蓟县、辽西、辽南和宣化等地 ,为利用离子探针 (SHRIMP)确定其同位素地质年代提供了可能。此外 ,本文对比了大连震旦系自生独居石和内蒙白云鄂博矿区东矿的独居石晶形和化学成分的相似性 ,再一次提出中国北方元古宙富稀土地层可能是内蒙古白云鄂博巨型稀土元素矿床的矿源层问题。  相似文献   

A visualization system for mineral elasticity     

Bijaya B. Karki  Ravi Chennamsetty 《Visual Geosciences》2004,9(1):49-57

The authors have developed an efficient visualization system to gain insight into large collections of mineral elasticity data produced by an increasing number of both theoretical calculations and experiments. The system allows us to visualize multivariate elastic moduli (i.e., elastic constant tensors) and their variation with composition, pressure and temperature. Moreover, it supports visualization of elastic wave propagation in an anisotropic medium by rendering the wave velocity data, which are calculated as a function of propagation direction in a three-dimensional space. This paper describes the design, implementation and application of the visualization scheme we have developed for mineral elasticity. In particular, our scheme exploits a combination of parallel coordinates, star plot, scatter plot and polygon-surface rendering techniques, which are implemented using OpenGL, GLUI and C++. The result is a highly portable and flexible interactive visualization system. For illustration, the elastic properties of several important oxide and silicate minerals are successfully visualized as a function of pressure and temperature.Reviewed by: D. Yuen, G. Erlebacher  相似文献   

磷酸盐矿物的孔道结构特征及其环境意义     

刘瑞  秦善  鲁安怀  王长秋  郑喜坤  王丽娟  赵东军 《地球科学进展》2004,(Z1)

黄磷铁矿、磷钠铍石、磷方沸石、簇磷铁矿、磷锰钠石、水磷铈石和磷灰石是非硅元素的孔道结构矿物。[PO_4]四面体和[MO_n]多面体共用角顶构成杂多面体格架。形成一维或多堆沿一定方向分布的孔道结构,孔道内由水分子和其它金属或非金属离子占据。孔道结构的磷酸盐矿物具有类似沸石矿物的分子筛效应,可与其它有害元素进行离子交换、孔道过滤和表面吸附等功能,是另一类重要的环境矿物材料。  相似文献   

青海湖沉积物的穆斯堡尔效应研究          下载免费PDF全文

祁永唐  J.Ensling  P.Guetlich 《盐湖研究》2004,12(3):11-15,19

对青海湖南岸QH86CK钻孔和湖中心水下QH85 -1 4钻孔的 3 6个沉积物样品进行了穆斯堡尔谱学测量。QH86CK钻孔样品常温下的穆斯堡尔谱由一个Fe2 + 双线分裂 ,一个Fe2 + 双线分裂和一个Fe3 + 六线分裂组成 ,而QH85 -1 4钻孔样品的谱可分解为两个Fe2 + 双线分裂和两个Fe3 + 双线分裂。在低温下 ,QH86CK钻孔样品的谱中出现了一个较强的Hhf=49 3T的磁分裂 ,而QH85 -1 4钻孔样品只有很小一部分Fe3 + 离子表现出磁有序。两个钻孔样品含铁矿物组成及其相对含量不同。QH86CK钻孔样品的Fe2 + Fe3 + 比值随深度有较大变化 ,而QH85 -1 4钻孔各个样品的Fe2 + Fe3 + 比值差别很小。这些结果表明青海湖南岸和湖中心水下的沉积环境不同  相似文献   

Synchrotron radiation X-ray diffraction in situ study of fine-grained minerals in shock veins of Suizhou meteorite   总被引：2，自引：0，他引：2  

XIE Xiande  SHU Jinfu & CHEN Ming . Guangzhou Institute of Geochemistry  Chinese Academy of Sciences  Guangzhou  China  . Geophysical Laboratory  Carnegie Institution of Washington  Washington  DC    USA Correspondence should be addressed to Xie Xiande 《中国科学D辑(英文版)》2005,48(6)

The Suizhou meteorite is an L6chondrite,which fell on April15,1986in Dayanpo,12.5km in the southeast of Suizhou City,Hubei Province,China[1].This meteorite is shock-metamorphosed to shock stage3—4[2].A few thin shock melt veins of0.02—0.09mm in width were observed in this chondrite[1,2].Similar to many other L6chondrites[3—5],the Suizhou shock veins contain two assemblages of high-pressure minerals[2,6—8]:(i)the“coarse-grained”assemblage of ringwoodite+majorite+NaAlSi3O8-hollandite…  相似文献   

X射线晶体学技术的发展及其在地球深部物质研究中的应用   总被引：1，自引：0，他引：1  

施倪承  李国武  马喆生  熊明 《矿物岩石》2005,25(3):27-31

随着光源更为全面的应用、探测器及计算技术方面的发展X射线晶体学技术得到了利用电子藕合探测器技术（CCD）对矿物晶体包括对地幔矿物及具有调制结构的矿物晶体结构的测定．开发出电子藕合探测器技术中的甘道菲（Gandolfi）方法。该方法不仅能对单晶样品进行德拜环的测定，而且可大量应用于难以取得单晶颗粒的样品的XRD研究．从而使得处于单晶（具有严格单一的晶体学取向）及粉晶（具有完全随机的晶体学取向）之间过渡类型的晶体的XRD研究成为可能。该方法与粉末衍射图谱的全谱拟合（Rietveld method）法相结合可解决粉晶结构解析和精修问题。  相似文献