粤东中生代花岗质火山-侵入杂岩成因的Nd同位素制约

运用Ｎｄ同位素及稀土元素Ｎｄ的含量关系对岩浆成因的制约,结合区域地质地球化学特征,确定粤东地区中生代花岗质火山－侵入杂岩的成因机制,不是幔源岩浆同化地壳物质并发生分离结晶作用以及壳幔两种来源岩浆的混合作用,而是地壳深熔作用,即古老地壳基底岩石的部分熔融作用。     

宁夏南部山区自然保护区的建设及旅游开发

分析了宁夏南部山区自然保护区的建设情况和存在的问题,提出了相应的建设方略,指出生态旅游是自然保护区开发和建设的有效途径     

南极磷虾与南大洋生态系统

南极磷虾在南极生态系统中起着至关重要的作用,是南大洋生态系统中初级生产的主要消费者,同时又是鱼类、乌贼、海豹、海鸟和鲸类的主要食物。由于其巨大的生物量,使其成为潜在的巨大渔业资源。     

诸广岩体南部辉绿岩脉特征及其与铀成矿关系

诸广岩基南部侵入于印支-燕山早期花岗岩中的辉绿岩脉广泛分布,早期(±140 Ma)辉绿岩脉多以近EW向分布,第二期(110~103 Ma)、第三期(±90 Ma)主要为NNW向或NEE向展布,属板内拉斑玄武岩系列。蚀变辉绿岩较相对新鲜辉绿岩明显富集K2O和MgO,轻微富集Al2O3,而明显贫Na2O与CaO;对比分析辉绿岩、花岗岩和富矿石三者地球化学特征,认为成矿组分Cr,Co,Ni和U等主要来源于花岗岩而不是辉绿岩。无矿化的新鲜辉绿岩、含矿破碎辉绿岩、花岗质碎裂岩富矿石三种不同岩性的样品的δ34SV-CDT值具有明显的分段特征,分别为-0.2‰~-0.5‰、-6.5‰~-10.9‰、-17.4‰~17.9‰,认为成矿热液的硫主要来自地层中的生物成因硫或沉积硫,可能部分来自花岗岩。辉绿岩脉中的矿化与辉绿岩脉经过了后期构造的切割和破碎有很大的关系,辉绿岩脉在铀成矿过程中的主要起物理化学界面的作用,它的侵入为成矿作用提供导矿和储矿构造。     

向斜—川南地区的新勘探目标

本文对川南地区地层岩性组合、构造形迹及其受力分析的基拙上,研究了向针中存在的三种储集空间,即向针转折端发育的追踪张裂缝为主千的裂缝网络、向针深部转折端的脱项现象造成的储集空间及低渗层原有的连通孔洞缝。本文进而探讨了形成向针裂缝型气藏的三个阶段,即早期聚集、改造成藏及平衡稳定阶段,指出在川南这个特定地区向抖是天然气勘探的新领域。     

Species of Antarctoscyphus Peña Cantero,García Carrascosa and Vervoort, 1997 (Cnidaria: Hydrozoa: Symplectoscyphidae) collected by US Antarctic expeditions: biogeographic implications

Antarctoscyphus is one of the most characteristic genera of Antarctic benthic hydroids, with nine of the 10 known species considered to be endemic to the Antarctic; only Antarctoscyphus elongatus is also present in the sub-Antarctic region of Kerguelen. Accordingly, the genus was considered to have an Antarctic–Kerguelen distribution. Here we present the results of the study of the species of Antarctoscyphus collected from different Antarctic areas and from the Magellan region, during several expeditions under the United States Antarctic Research Program between 1958 and 1986. A scanning electron microscopy survey of all known species of the genus was carried out. Eight of the 10 known species of Antarctoscyphus were found in the collection, with A. spiralis and A. elongatus being the most frequently found species, whereas A. biformis, A. fragilis and A. gruzovi were found only once. The type material of A. biformis was reviewed and re-described. This study represents the second records for A. biformis and A. fragilis. The new records allow updating of the biogeographic knowledge on the distribution of several species: A. mawsoni, so far considered endemic to East Antarctica, and A. asymmetricus, considered endemic to West Antarctica, are here considered to have a Circum-Antarctic distribution. Additionally, A. fragilis, previously considered endemic to the Weddell Sea, is now considered to have a West Antarctic–Patagonian distribution, as it was recorded off the Pacific Magellan region. The records gathered here allow us to change the distribution pattern of the genus from Antarctic–Kerguelen to Pan-Antarctic. The study has allowed us to increase the known bathymetric range for some species, some reaching much deeper waters than previously known. Hence, A. fragilis, A. grandis and A. mawsoni, hitherto considered shelf species, are reported from bathyal bottoms of the continental slope. A general discussion on the bathymetric and geographic distribution of all known species is included.

www.zoobank.org/urn:lsid:zoobank.org:pub:1C7ED3F2-3FF1-4C5C-85BB-FAAF557AC2ED     

Mysidacés (Crustacea) de Kerguelen,Crozet et Bouvet (Océan Austral) récoltés par la Japonaise,le Marion-Dufresne (1972–82) et dans des contenus stomacaux d'oiseaux

This study deals with the Mysidacea (Crustacea) collected during the cruises organized by T.A.A.F. (Terres Australes et Antarctiques Françaises), between 1972 and 1982, in the subantarctic part of the Southern Ocean, off Bouvet, Marion, Prince Edward, Crozet, Kerguelen and Heard Islands. In spite of the large numbers of samples taken between the littoral and 2000 m, with various bottom sampling gears, only 8 species were caught. At the Kerguelen islands, the genus Mysidetes, with 2 species including M. morbihanensis n. sp., was the main constituent of the benthic littoral mysidacean fauna, while Boreomysis inermis was the main bathyal species. The analysis of stomach contents of birds indicates that some bathypelagic mysidacean species ascend to the surface layer.     

New and little-known genera of cheilostome Bryozoa from the New Zealand region

The diagnostic characters of the cavernicolous genus Spelaeoblatta Bolívar, 1897, previously known only from a female, are given based on the male of S. thamfaranga n. sp. from Thailand. Nocticola adebratti n. sp. from Sabah is described.     

豫南燕山期花岗岩蠕变特性及非线性蠕变损伤模型

豫南信阳地区燕山期高钾钙碱性I型花岗岩分布广泛,岩石性质对深埋地下洞室围岩开挖及支护设计具有重要影响。以豫南某大型水电站地下厂房区花岗岩为研究对象,在对其地质分布情况及矿物成分调查测试基础上,进行三轴压缩蠕变试验,揭示了围岩蠕变特性及加载过程中的损伤演化性质,采用等时曲线法进行花岗岩蠕变长期强度分析。考虑蠕变过程中岩石发生的损伤累积,建立变黏性系数的黏壶元件,并代替传统西原正夫模型中Newton黏壶,构建了能够描述加速蠕变阶段的蠕变损伤模型。结果表明：在整个蠕变过程中,花岗岩的总变形量以瞬时弹性变形为主,最终的蠕变破坏表现出脆性剪切破坏的特征;围压对剪切裂缝的扩展具有主要抑制作用;长期强度随围压增大而减小,与常规三轴试验结果相比,长期强度分别下降6.37%和21.0%;采用Levenberg-Marquardt优化算法+通用全局优化算法对非线性蠕变损伤模型进行参数辨识及拟合,理论值与试验值吻合较好,验证了非线性蠕变损伤模型对于岩石全过程蠕变特征描述的合理性及适用性。研究成果对保障豫南燕山期花岗岩地区的工程建设优化设计和安全建设具有重要意义。     

准噶尔盆地南缘艾维尔沟群物源与古流分析

目的恢复准噶尔盆地南缘地区中—晚侏罗世原盆地沉积环境格局,为进一步研究准噶尔盆地南缘地区的构造特征提供支持。方法根据岩石碎屑组分基本数据,运用地层厚度、砂岩百分含量、古水流、砂岩成分、重矿物成分进行系统分析。结果研究区古流总体自东而西、自南而北,伊林哈比尔尕山以南和博格达山内部为准噶尔盆地南缘下中侏罗统艾维尔沟群的主要物源区。结论艾维尔沟群物源样品反映了被动大陆边缘构造环境和活动大陆边缘构造环境,沉积环境以干旱—半干旱型气候环境为主。