A Sm－Nd mineral isochron of mafic granulite from the Sφstrene Island， East Antarctica

任留东，刘小汉ＡＳｍ－ＮｄｍｉｎｅｒａｌｉｓｏｃｈｒｏｎｏｆｍａｆｉｃｇｒａｎｕｌｉｔｅｆｒｏｍｔｈｅＳφｓｔｒｅｎｅＩｓｌａｎｄ，ＥａｓｔＡｎｔａｒｃｔｉｃａ￥ＲｅｎＬｉｕｄｏｎｇ（ＩｎｓｔｄｕｔｅｏｆＧｅｏｌｏｇｙ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏ...     

Holocene ostracoda and sedimentary environment implication in The core NG93－1 from the Great Wall Bay， Antarctica

蔡慧梅ＨｏｌｏｃｅｎｅｏｓｔｒａｃｏｄａａｎｄｓｅｄｉｍｅｎｔａｒｙｅｎｖｉｒｏｎｍｅｎｔｉｍｐｌｉｃａｔｉｏｎｉｎＴｈｅｃｏｒｅＮＧ９３－１ｆｒｏｍｔｈｅＧｒｅａｔＷａｌｌＢａｙ，Ａｎｔａｒｃｔｉｃａ￥ｃａｉｈｕｉｍｅｉ（ＳｏｕｔｈＣｈｉｎａＳｅａ...     

A preliminary analysis of the pigments from ice algae in theadjacentwatersofGreatWallStation，Antarctica

ＡｐｒｅｌｉｍｉｎａｒｙａｎａｌｙｓｉｓｏｆｔｈｅｐｉｇｍｅｎｔｓｆｒｏｍｉｃｅａｌｇａｅｉｎｔｈｅａｄｊａｃｅｎｔｗａｔｅｒｓｏｆＧｒｅａｔＷａｌｌＳｔａｔｉｏｎ，ＡｎｔａｒｃｔｉｃａＬｉＢａｏｈｕａ（李宝华）；ＨｕａｎｇＦｅｎｇｐｅｎｇ（黄凤鹏）...     

A study on nano－ and microdiatoms in the intertidal zones of Zhongshan Station，Antarctica

Ａｓｔｕｄｙｏｎｎａｎｏ－ａｎｄｍｉｃｒｏｄｉａｔｏｍｓｉｎｔｈｅｉｎｔｅｒｔｉｄａｌｚｏｎｅｓｏｆＺｈｏｎｇｓｈａｎＳｔａｔｉｏｎ，ＡｎｔａｒｃｔｉｃａＺｈｕＧｅｎｈａｉ（朱根海）；ＬｕＤｏｕｄｉｎｇ（陆斗定）ａｎｄＷａｎｇＺｉｐａｎ（王自磐）（Ｓ...     

Species composition and quantitative variation of zooplankton in the Great Wall Bay and its adjacent waters，Antarctica

ＳｐｅｃｉｅｓｃｏｍｐｏｓｉｔｉｏｎａｎｄｑｕａｎｔｉｔａｔｉｖｅｖａｒｉａｔｉｏｎｏｆｚｏｏｐｌａｎｋｔｏｎｉｎｔｈｅＧｒｅａｔＷａｌｌＢａｙａｎｄｉｔｓ　ａｄｊａｃｅｎｔｗａｔｅｒｓ，ＡｎｔａｒｃｔｉｃａＨｕａｎｇＦｅｎｇｐｅｎｇ（黄凤鹏）ａｎｄ...     

Magnetotelluric sounding study in the region of Zhongshan Station，East Antarctica

ＭａｇｎｅｔｏｔｅｌｌｕｒｉｃｓｏｕｎｄｉｎｇｓｔｕｄｙｉｎｔｈｅｒｅｇｉｏｎｏｆＺｈｏｎｇｓｈａｎＳｔａｔｉｏｎ，ＥａｓｔＡｎｔａｒｃｔｉｃａＫｏｎｇＸｉａｎｇｒｕ（孔祥儒）ａｎｄＺｈａｎｇＪｉａｎｊｕｎ（张建军）（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈ...     

The characteristics of Pi2 pulsations at Great Wall Station,Antarctica

ＴｈｅｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＰｉ２ｐｕｌｓａｔｉｏｎｓａｔＧｒｅａｔＷａｌｌＳｔａｔｉｏｎ，ＡｎｔａｒｃｔｉｃａＹａｎｇＳｈａｏｆｅｎｇ（杨少峰）ａｎｄＸｉａｏＦｕｈｕｉ（肖福辉）（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈｙｓｉｃｓ，Ａｃａｄｅｍ...     

The separation and identification of phytoplankton pigments from the adjacent waters of Great Wall Station，Antarctica

ＴｈｅｓｅｐａｒａｔｉｏｎａｎｄｉｄｅｎｔｉｆｉｃａｔｉｏｎｏｆｐｈｙｔｏｐｌａｎｋｔｏｎｐｉｇｍｅｎｔｓｆｒｏｍｔｈｅａｄｊａｃｅｎｔｗａｔｅｒｓｏｆＧｒｅａｔＷａｌｌＳｔａｔｉｏｎ，ＡｎｔａｒｃｔｉｃａＬｉＢａｏｈｕａ（李宝华）；ＨｕａｎｇＦｅｎ...     

The pigmental composition and the absorption spectral analysis of Ulothrix sp．and benthic diatoms in the intertidal zone of Great Wall Station，Antarctica

ＴｈｅｐｉｇｍｅｎｔａｌｃｏｍｐｏｓｉｔｉｏｎａｎｄｔｈｅａｂｓｏｒｐｔｉｏｎｓｐｅｃｔｒａｌａｎａｌｙｓｉｓｏｆＵｌｏｔｈｒｉｘｓｐ．ａｎｄｂｅｎｔｈｉｃｄｉａｔｏｍｓｉｎｔｈｅｉｎｔｅｒｔｉｄａｌｚｏｎｅｏｆＧｒｅａｔＷａｌｌＳｔａｔｉｏｎ，Ａｎ...     

Characteristics of Pc3 pulsations at Great Wall Station,Antarctica

（杨少峰）（肖福辉）ＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＰｃ３ｐｕｌｓａｔｉｏｎｓａｔＧｒｅａｔＷａｌｌＳｔａｔｉｏｎ，Ａｎｔａｒｃｔｉｃａ￥ＹａｎｇＳｈａｏｆｅｎｇａｎｄＸｉａｏＦｕｈｕｉ（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈｙｓｉｃｓ，Ａｃａｄｅｍｉａ...     

西南极乔治王岛长城站区晚第四纪燕窝湖岩芯元素地球化学特征

本文阐述了乔治王岛长城站区燕窝湖沉积物中微量元素及某些常量元素的含量、分布、富集系数和相关系数的变化规律 ,探讨了该湖岩芯物质来源及气候环境的阶段性变迁 ,认为一方面燕窝湖周围碎屑沉积岩 (包括火山沉积岩 )是进入沉积体系的主要物源 ;另一方面 ,地幔物质也是其物源之一 ;同时 ,并不排除南极大陆冰进期搬运来的陆源物质进入沉积体系。     

Evolution of clay mineral assemblages and organic matter in the late glacial-Holocene sedimentary infill of Lake Annecy, (northwestern Alps): paleoenvironmental implications

The basin fill of Lake Annecy was investigated from a 44 m core which reached down to glacial sediments of the last glaciation (called Würm in the alpine areas). We analyzed three main parameters: sediment texture (optical microscopy and laser microgranulometry), clay mineral assemblages (CMA by XRD), and organic matter (OM by Rock-Eval pyrolysis). Settling of suspended load, under variable hydrodynamic conditions is the main depositional process. Both CMA and OM provenances can be recognized for the different sedimentary and igneous-metamorphic formations (Carboniferous to Quaternary, and older crystalline basement) and corresponding areas, in the surrounding region of Lake Annecy. Oligocene-Miocene molasses, Early Cretaceous marls, and Early-Middle Jurassic marls and shales are the main sedimentary sources. Two distinct processes were operating: destruction of glacial sediments (till sensu largo) and reworking, or direct erosion and run-off from ice-free catchment areas. Clay minerals related to pedogenesis, and non-reworked terrestrial and lacustrine OM, were progessively added to these primary sources during the Late Würmian/Holocene transition to warmer climatic conditions. Rapid modifications of CMA and OM sources during the earlier phase of sedimentary infilling (Unit 2) suggest that valley glaciers connected to the lake basin almost completely disappeared within a few centuries.     

南极长城站区燕窝湖岩芯中稀土元素特征

本文通过对长城站区燕窝湖岩芯沉积物中稀土元素丰度、分布模式、特征参数和稀土元素之间以及其他元素的相关系数研究,探讨了该湖岩芯的物质来源。研究结果表明,燕窝湖岩芯沉积物中REE分布模式与菲尔德斯半岛火山岩类较相似,并与长城湾表层沉积物类同,表明它们的物质来源具有同源性。山此推论,该湖岩芯沉积物的母岩主要来自菲尔德斯半岛火山沉积碎屑岩,并保留了岛弧型的特征。同时,还表明该湖盆沉积环境系以干旱的冰川环境为主导,化学风化十分微弱。     

民勤盆地东北部晚第四纪深湖亚相地层空间分布及其环境意义

民勤盆地位于石羊河下游,现今大面积地区已被风沙覆盖.前人的研究报道了在民勤盆地的东部曾经发育过一个面积巨大的"腾格里古大湖",然而尚不明确民勤盆地是否也曾被湖水覆盖.为此,本文收集整理了民勤盆地中8个水文地质钻孔的地层资料,利用GIS技术重现了研究区地表以下50 m深度内的湖相地层的空间分布特征.分析发现,在盆地的不同地区普遍发育了2~3层深湖亚相地层,部分地区甚至多达4层,各湖相层厚度介于0.5~32 m.区域地层对比结果显示,在某个时段研究区大范围地区普遍发育了深水湖泊,而其他时段则在不同地区零星发育了小湖泊.结合研究区已有的测年资料,本文认为在晚第四纪某个时段(倒数第二层深湖亚相发育阶段),整个研究区内曾经存在一个规模较大的连通湖泊;但民勤盆地晚第四纪不同阶段深湖亚相地层差异明显的空间分布特征,可能反映了湖盆沉积中心自东向西、再向北东的迁移过程.     

Late Archean basement in the Bangenhuken Complex of the Nordbreen Nappe, western Ny-Friesland, Svalbard

The rocks of western Ny-Friesland, northern Svalbard, are part of a tectonostratigraphy including four thrust sheets, each composed mainly of orthogneisses overlain by younger metasedimentary rocks. Previous geochronological studies have shown that the orthogneisses are dominated by ca. 1750 Mya granitoids. This study of a quartz-monzonite in one of the thrust sheets, the Nordbreen Nappe, yields a single-zircon U-Pb ion-microprobe age of 2709 Ø 28 My. This is the oldest rock unit so far reported in the Svalbard Caledonides. However, age-determinations on detrital zircons in the metasediments of western Ny-Friesland have shown that Late Archean rocks were prominent sources. The new ages presented here provide the first evidence of a local source for these sedimentary rocks.     

西南极利文斯顿岛百耳斯半岛火山岩的同位素年龄

以Ｋ－Ａｒ稀释法和４０Ａｒ／３９Ａｒ阶段加热法对利文斯顿岛百尔斯半岛的熔岩和次火山岩测定了同位素年龄。新的年龄数据表明,该区火山活动在晚侏罗纪末即已开始,一直持续到晚白垩世,存在着三期火山活动的产物。侏罗纪末～早白垩世初的火山活动除有熔岩（１４６Ｍａ,１３７Ｍａ）喷出外,还发育有辉长岩侵入体（１３５Ｍａ）和辉绿岩岩墙（１２９Ｍａ）等次火山岩。安山岩（１１４Ｍａ）和石英斑岩（９４Ｍａ）则是早白垩世火山活动的结果。半岛东部具沉积夹层的玄武岩（７１Ｍａ）是区域上晚白垩世～早第三纪火山活动的代表。     

Tectonic controls on a large landslide complex: Williams Fork Mountains near Dillon, Colorado

An extensive ( 25 km²) landslide complex covers a large area on the west side of the Williams Fork Mountains in central Colorado. The complex is deeply weathered and incised, and in most places geomorphic evidence of sliding (breakaways, hummocky topography, transverse ridges, and lobate distal zones) are no longer visible, indicating that the main mass of the slide has long been inactive. However, localized Holocene reactivation of the landslide deposits is common above the timberline (at about 3300 m) and locally at lower elevations. Clasts within the complex, as long as several tens of meters, are entirely of crystalline basement (Proterozoic gneiss and granitic rocks) from the hanging wall of the Laramide (Late Cretaceous to Early Tertiary), west-directed Williams Range thrust, which forms the western structural boundary of the Colorado Front Range. Late Cretaceous shale and sandstone compose most footwall rocks. The crystalline hanging-wall rocks are pervasively fractured or shattered, and alteration to clay minerals is locally well developed. Sackung structures (trenches or small-scale grabens and upslope-facing scarps) are common near the rounded crest of the range, suggesting gravitational spreading of the fractured rocks and oversteepening of the mountain flanks. Late Tertiary and Quaternary incision of the Blue River Valley, just west of the Williams Fork Mountains, contributed to the oversteepening. Major landslide movement is suspected during periods of deglaciation when abundant meltwater increased pore-water pressure in bedrock fractures.A fault-flexure model for the development of the widespread fracturing and weakening of the Proterozoic basement proposes that the surface of the Williams Range thrust contains a concave-downward flexure, the axis of which coincides approximately with the contact in the footwall between Proterozoic basement and mostly Cretaceous rocks. Movement of brittle, hanging-wall rocks through the flexure during Laramide deformation pervasively fractured the hanging-wall rocks.     

Example of a supradetachment basin within a pull-apart tectonic setting: Mormon Point, Death Valley, California

The geological features now exposed at Mormon Point, Death Valley, reveal processes of extension that continue to be active, but are concealed beneath the east side of Death Valley. Late Cenozoic sedimentary rocks at Mormon Point crop out in the hangingwall of the Mormon Point low-angle normal fault zone, a fault zone that formed within a releasing bend of the oblique-slip (right-normal slip) fault zone along the east side of Death Valley. The late Cenozoic sedimentary rocks were part of the valley when the low-angle fault zone was active, but during late Quaternary time they became part of the Black Mountains block and were uplifted. Rocks and structures exposed at Mormon Point are an example of the types of features developed in a releasing bend along the margins of a major pull-apart structure, and in this example they are very similar to features associated with regional detachment faults. The oldest sedimentary rocks in the hangingwall of the Mormon Point low-angle fault zone dip steeply to moderately east or north-east and were faulted and rotated in an extensional kinematic environment different from that recorded by rocks and structures associated with younger rocks in the hangingwall. Some of the younger parts of the late Cenozoic sedimentary rocks were deposited, faulted and rotated during movement on the Mormon Point low-angle normal fault. Progressively, strata are less faulted and less rotated. The Mormon Point low-angle normal fault has an irregular fault surface whose segments define intersections that plunge 18°-30°, N10°-40°W, with a maximum of 22°, N22°W that we interpret to be the general direction of slip. Thus, even though Death Valley trends north, movement on the faults responsible for its formation was at least locally north-northwest. Gouge and disrupted conglomerates along the faults are interpreted to have formed either as adjustments to accommodate space problems at the corners of blocks or along faults that bounded blocks during their displacement and rotation. The younger units of the late Cenozoic sedimentary rock sequence and the geomorphic surfaces developed on them are rarely faulted, not rotated, and overlap the Mormon Point low-angle faults. Active faults cut Holocene alluvium north of the late Cenozoic rocks and form the present boundary between Mormon Point and the Black Mountains. The distribution of active faults defines a releasing bend that mimics the older releasing bend formed by the Mormon Point low-angle fault zone. Rocks and structures similar to those exposed above the Mormon Point low-angle fault zone are probably forming today beneath the east side of Death Valley north-west of Mormon Point.     

西南极乔治王岛菲尔德斯半岛火山岩地质初步研究

西南极乔治王岛菲尔德斯半岛主要由基性熔岩、火山碎屑岩及薄层沉积岩组成,并有次火山岩体及脉岩发育.野外观察及K—Ar,Rb—Sr全岩年龄说明岩石形成于始新一渐新世.主要元素和微量元素地球化学特征说明岩石属低钾高铝钙碱性玄武岩,但具有拉斑玄武岩的某些特征,是岛弧火山活动的产物.岩层呈平缓单斜,发育有近同期及后期走滑正断层,以及由断层活动形成的局部以称褶皱.     

The interplay of geomorphic processes and soil development in an upland environment, Calabria, South Italy

Five representative soil profiles outcropping in the area around the Cecita Lake (Calabria, South Italy) were characterised by field work, chemical and mineralogical analyses, optical and scanning electron microscopy. Interactions among weathering, pedogenesis and geomorphic processes are emphasised, in an attempt to link the results obtained at different scales of observation. The important role of topography in controlling soil development or removal by erosive processes is discussed, in relation to the natural geomorphological context and the effects of human pressure. Both present-day and relict features were recognised in the studied soils, and discussed in terms of environmental conditions and climatic changes. The chemical composition of volcanoclastic components identified in some soil horizons with Andosol-like field appearance, coupled with pedogenetic features, contributed useful chronological constraints for the reconstruction of Late Quaternary geomorphic events.