昆仑山口西8.1级地震前青海省形变及地温前兆特征分析

通过对青海省地倾斜、地应力、深井地温3种前兆手段在昆仑山口西8．1级地震前异常的分析与研究，得出了强地震远场前兆的一些初步特征，并与近场前兆异常特征做了比较，这对该省今后强震短期预报将是有益的。     

天山北麓灌溉绿洲的形成和发展

17世纪以前，天山北麓是以牧为主地区，由“兵屯”建立的古代绿洲仅在交通要道呈星、点分布，且屡兴屡废。18－20世纪中叶，由清朝到民国，大力发展屯田，使社会发展进入半农半牧时期，这里形成的旧绿洲，呈断续岛状小片。1949年以后，由大规模农垦建立的新绿洲群，把分散小片旧绿洲联结在一起，形成与天山相平行绿洲带。本区绿洲形成特点是由屯垦和内地移民发展起来，起步虽晚，但发展很快；而且古绿洲、旧绿洲和新绿洲之间有延续性，不象塔里大盆地的很多古代绿洲已沦为沙漠、戈壁或风蚀地。     

4280 a B.P.太行山大地震与大禹治水后(4070a B.P.)的黄河下游河道

我国古籍所载黄河下游最早河道有禹贡河和山经河，它们在今郑州以北均沿太行山东麓北流。其原因可能与公元前4280年太行山大地震有关。     

东南极格罗夫山泛非期麻粒岩相变质作用

东南极格罗夫山主要由麻粒岩相高级变质岩和花岗岩类组成，其中变质岩以浅色和暗色含斜方辉石长英质片麻岩占主导地位，夹有少量镁铁质麻粒岩、变沉积岩和含方柱石钙硅酸盐岩。这些岩石一般都展示了平衡的矿物共生结构，但在镁铁质麻粒岩的单斜辉石中普遍发育斜方辉石(易变辉石)的出溶片晶。根据出溶辉石的重组分析获得麻粒岩相变质作用的峰期温度约为850℃，而浅色片麻岩中的石榴子石—斜方辉石—斜长石—石英组合给出的变质压力为0．61～0．67GPa。镁铁质麻粒岩中火成亚钙质普通辉石斑晶的保存表明格罗夫山地区可能只发育单一的泛非期高温麻粒岩相变质事件，岩石在高温变质之后经历了缓慢冷却过程，这主要归因于花岗质岩浆的板底垫托作用。     

0．7Ma以来的念青唐古拉山脉隆升过程——来自冰川剥蚀作用的证据

通过对念青唐古拉山冰碛地层划分及冰碛物同位素测年，发现最早一期冰碛物形成于0．7～0．6MaBP，指示自中更新世以来念青唐古拉山脉开始隆升，主峰地区发生了大规模的冰川剥蚀作用，形成了大面积分布的冰碛高平台；0．2～0．14MaBP念青唐古拉山又快速隆升，并堆积了刚刚伸出各大沟谷口的高侧碛；0．07～0．03MaBP念青唐古拉山再次小规模隆起，形成各大沟谷内的侧碛和终碛垄；0．01Ma BP还有小规模冰川活动。念青唐古拉山主峰地区的冰川剥蚀作用反映出的山脉隆升过程，可较好地与青藏高原的隆起过程相对比，它应是青藏高原隆升的响应。     

大别山超高压石榴多硅白云母片岩中钻石U－Pb年龄

大别山超高压石榴多硅白云母片岩中钻石Ｕ－Ｐｂ年龄刘晓春（中国地质科学院地质力学研究所，北京１０００８１）李惠民，左义成（地质矿产部天津地质矿产研究所，天津３００１７０）关键词石榴多硅白云母片岩，Ｕ－Ｐｈ年龄，早元古代表壳岩，印支期超高压变质，大别山高...     

毛洋头铀（银,钼）矿床同位素地球化学研究

毛洋头铀矿床的（Ｈ、Ｏ）同位素特征表明：早期矿化热液主要为岩浆水，而晚期矿化热液则主要为大气降水。铅同位素组成反映该矿床中铅为不同来源的混合铅。Ｃ、Ｓ同位素组成变化范围小，且与火成岩的Ｃ、Ｓ同位素组成相当，说明矿床中的碳和硫主要淋取于火成围岩或源于地壳深部。     

Geochemistry of the subduction-related magmatic rocks in the Dahong Mountains, northern Hubei Province——Constraint on the existence and subduction of the eastern Mianle oceanic basin

Being a composite collisional orogen between North China and South China blocks, the Qinling orogenic belt is the key to understand the composite combination, prolonged evolutionary history and their continental dynamics. The main suture between north and south Qinling, called Shangdan suture zone (SDSZ), had been studied in detail for about twenty years. Recently, another suture zone, called Mianl黣 suture zone (MLSZ), has been identified in the Qinling Mountains. It is characterized b…     

The Frozen Soils and Devastating Characteristics of West Kunlun Mountains Pass Ms 8.1 Earthquake Area in 2001

The investigation on damages to frozen soil sites during the West Kunlun Mountains Pass earthquake with Ms 8.1 in 2001 shows that the frozen soil in the seismic area is composed mainly of moraine, alluvial deposit, diluvial deposit and lacustrine deposit with the depth varying greatly along the earthquake rupture zone. The deformation and rupture of frozen soil sites are mainly in the form of coseismic fracture zones caused by tectonic motion and fissures,liquefaction, seismic subsidence and collapse resulting from ground motion. The earthquake fracture zones on the surface are main brittle deformations, which, under the effect of sinlstral strike-slip movement, are represented by shear fissures, tensional cracks and compressive bulges. The distribution and configuration patterns of deformation and rupture such as fissures, liquefaction, seismic subsidence and landslides are all related to the ambient rock and soil conditions of the earthquake area. The distribution of earthquake damage is characterized by large-scale rupture zones, rapid intensity attenuation along the Qinghai-Xizang (Tibet) Highway, where buildings distribute and predominant effect of rock and soil conditions.