内蒙古好老鹿场地区晚古生代超基性-基性岩的发现及意义

在内蒙古东部好老鹿场地区1∶5万区调工作中,发现了一套新的岩石组合,分别由铁镁质堆积岩、基性岩墙群、蚀变基性火山岩等组成.该套岩石组合经较强的构造破坏,呈大小不等的岩块产于本巴图组砂板岩之中.总体延伸方向呈近东西向展布,明显受区域性构造控制.岩石化学、岩石地球化学等方面的资料表明,辉石橄榄岩、辉长岩具有低Al、贫Ca和富Na的特点, MgO / (MgO+FeO)比值为0.25,MgO含量偏低.稀土元素总量偏低,为76.03×10-6 ~ 114.81×10-6,轻重稀土富集不明显,分馏作用较弱.∑L/∑H为0.73 ~ 0.8,配分曲线呈平坦的"W"型,δEu =1.03 ~ 1.23,略显正异常.基性火山岩具明显的富Fe、Mg、Na,贫Al、Ti、K的特征,微量元素显示形成于洋中脊环境.同时在辉长岩中获得单颗粒锆石UPb年龄为362.4 Ma,时代为早泥盆世晚期.其形成环境为洋中脊,属于泥盆纪古亚洲洋消减部分的残留体.     

新疆东准库布苏金矿床石英矿物标型特征及找矿评价意义

新疆东准库布苏金矿床石英矿物标型特征及找矿评价意义张旺生高怀忠吕瑞英（中国地质大学,武汉４３００７４）关键词石英标型特征找矿评价东准噶尔新疆１金矿成矿阶段石英的一般特征库布苏金矿位于新疆东准噶尔野马泉南约１６ｋｍ,矿区所属构造单元为西伯利亚板块准噶...     

Comparative phylogeography of African rain forest trees: A review of genetic signatures of vegetation history in the Guineo-Congolian region

The biogeographic history of the African rain forests has been contentious. Phylogeography, the study of the geographic distribution of genetic lineages within species, can highlight the signatures of historical events affecting the demography and distribution of species (i.e. population fragmentation or size changes, range expansion/contraction) and, thereby, the ecosystems they belong to. The accumulation of recent data for African rain forests now enables a first biogeographic synthesis for the region. In this review, we explain which phylogeographic patterns are expected under different scenarios of past demographic change, and we give an overview of the patterns detected in African rain forest trees to discuss whether they support alternative hypotheses regarding the history of the African rain forest cover. The major genetic discontinuities in the region support the role of refugia during climatic oscillations, though not necessarily following the classically proposed scenarios. We identify in particular a genetic split between the North and the South of the Lower Guinean region. Finally we provide some perspectives for future study.     

珠江三角洲城市地质问题及对策

珠江三角洲地区的城市地质问题主要有地表塌陷、地裂缝、泥石流、滑坡和崩塌以及软土沉陷等。其成因除最直接的自然因素所致外,还有人为不合理的生产和生活活动诱发而加剧城市地质问题的发生发展。根据珠江三角洲城市地质问题的现状,提出了城市地质问题的防治对策。     

莺歌海盆地中央泥底辟带气田水地球化学特征及其油气地质意义

以莺歌海盆地东方区和乐东区气田水样品水化学常规分析为切入点,利用气田水矿化度、水型、钠氯系数(变质系数)、脱硫系数,氯镁系数等参数,深入分析了两区气田水地球化学特征及水化学组合参数特征,并判识对比了两区气藏封闭程度及其保存条件。在此基础上,结合莺歌海盆地天然气成藏地质条件,重点剖析了两区气田水分布规律及成因控制因素,探讨了两区气田水与天然气运聚成藏之间的成因联系。强调指出,两区气田水具有相似的形成演化特征,天然气保存条件好,但对比两区气田水的水化学组合参数,乐东区天然气保存条件稍差于东方区;东方区气田水以NaHCO3水型占绝对优势,其分布规律与断裂系统存在密切联系。该区水文地质开启程度差,气藏盖层封闭性好,有利于天然气富集成藏。乐东区气田水类型多样,成因复杂,天然气保存条件较好但相对东方区稍差。两区气田水具分区分块分布规律,莺歌海盆地泥底辟及其伴生热流体活动对气田水成因及分布规律与天然气运聚成藏等均具有重要控制作用和影响。     

Influence of igneous processes and serpentinization on geochemistry of the Logatchev Massif harzburgites (14°45′N,Mid-Atlantic Ridge), and comparison with global abyssal peridotites

We acquired bulk-rock analyses of Mid-Atlantic Ridge (MAR) harzburgites in order to understand the influence of submarine igneous and metamorphic processes on the distribution of incompatible elements (especially rare Earth elements or REEs) in abyssal peridotites. The geochemical characteristics of these Logatchev Massif serpentinized and talc-altered harzburgites, and spatially associated metagabbros were then compared with a compilation of global abyssal peridotites. The Logatchev harzburgites show light rare earth element (LREE) enrichments (average La _N /Yb _N = 2.81), positive correlations between LREEs (e.g. La, Ce, Pr, and Nd) and high field strength elements (HFSEs; e.g. Nb and Zr), and positive correlations between HFSEs and Th. Most global abyssal peridotites show similar trends. We suggest that the systematic enrichment of incompatible elements probably reflects a post-partial fusion magmatic refertilization. The compositional scatter exhibited by some serpentinized peridotites in Nb-LREE diagrams is probably due to the elimination of diopside during partial melting and significant impregnation by a melt produced in the Opx–Ol–Sp melting field rather than to later hydrothermal alteration. The correlation between Pb and Nd observed for most global abyssal peridotites, including the Logatchev harzburgites, indicates magmatic generation. The scatter of Pb in some rocks suggests that lead is likely mobile during serpentinization or weathering. Low to moderate water/rock (W/R) ratios in the harzburgites calculated from Sr isotopic compositions (5.98–26.20 for a close system and 1.66–2.72 for an open system), and the low abundance of REEs in Logatchev hydrothermal fluids indicate that the REE contents of abyssal peridotites probably were little influenced by hydrothermal alteration. Compared to this later alteration, the presence of small proportions of gabbroic melt (from 1:30 to 1:3 in our sample) that crystallized in the residual harzburgites modified their REE patterns significantly by elevating the LREEs.     

几种新的河网分维及其制图特征

利用分形几何原理，推导出几种新的河网分维，并讨论了它们的制图特征。     

米仓山隆起带西缘灯影组铅锌找矿潜力评价

较系统全面地叙述了米仓山隆起带灯影组铅锌矿成矿地质条件,为在其西缘寻找与陕西马元铅锌矿相同矿床类型矿产的找矿潜力进行了评价。     

对鄂尔多斯盆地周边岩溶水系统的几点认识

鄂尔多斯盆地地周边分布的古生界碳酸盐岩赋存有丰富的岩溶地下水，受背景地质条件的控制，不同地段地层岩性，岩溶发育程度，岩溶水的补给和赋存富集规律均有差异，并形成了多个岩溶水系统。     

泰安市地质灾害预警预报系统研究

主要介绍了泰安市地质灾害气象风险预警与指挥系统。系统开发的主要目的是为了更好的与泰安市地质灾害防治工作相结合,通过对气象因素及地质灾害资料的分析和研究,基于地质灾害气象预警模型,采用先进的 GIS 技术能实现对地质灾害易发风险性区域预警,能直观地了解到各部分区域的地质灾害易发风险性,为各级政府防灾减灾提供科学的技术支撑。