夏季华北地区高空槽前有无暴雨的对比分析

本文通过两个个例的对比分析,研究夏季华北在什么条件下高空槽过境时会引起暴雨。发现有暴雨出现的高空槽,处于继续发展阶段,水汽充沛,在大尺度上升运动区域内,有中间尺度系统存在。而没有暴雨的高空槽,则转向衰减阶段,水源不足,没有中间尺度系统、 文中还给出高空槽暴雨的各种参数,这对预报有参考意义。     

我国东部几个中新生代盆地泥质岩中的氨基酸

从现代沉积物到前寒武纪的沉积岩中都发现有氨基酸的存在。关于它们的组成、含量及其地质意义在许多文献中都曾涉及到,特别是对近代各种环境沉积中的氨基酸及其在成岩作用过程中的变化,已经积累了相当多的分析资料。本文对以渤海第三纪沉积盆地为主的我国东部地区中新生代泥质岩样品进行了氨基酸的分析,并初步讨论了这些分析结果与沉积环境的关系。     

Deformation at the Easternmost Altyn Tagh Fault: Constraints on the Growth of the Northern Qinghai–Tibetan Plateau

How the Altyn Tagh fault(ATF) extends eastwards is one of the key questions in the study of the growth of the Qinghai–Tibetan Plateau. Detailed fieldwork at the easternmost part of the ATF shows that the ATF extends eastward and bypasses the Kuantan Mountain; it does not stop at the Kuantan Mountain, but connects with the northern Heishan fault in the east. The ATF does not enter the Alxa Block but extends eastward along the southern Alxa Block to the Jintanan Mountain. The Heishan fault is not a thrust fault but a sinistral strike-slip fault with a component of thrusting and is a part of the ATF. Further to the east, the Heishan fault may connect with the Jintananshan fault. A typical strike-slip duplex develops in the easternmost part of the ATF. The cut and deformed Quaternary sediments and displaced present gullies along the easternmost ATF indicate that it is an active fault. The local highest Mountain(i.e., the Kuantan Mountain) in the region forms in a restraining bend of the ATF due to the thrusting and uplifting. The northward growth of the Qinghai–Tibetan Plateau and the active deformation in South Mongolia are realized by sinistral strike-slipping on a series of NE–SW-trending faults and thrusting in restraining bends along the strike-slip faults with the northeastward motion of blocks between these faults.     

Sequence stratigraphy of Jurassic-Cretaceous boundary strata in Luanping,Northern Hebei,China

Division and correlation of terrestrial J-K bound are a knotty-argued problem. The key to solving the problem is to find a deposition-continuous section. Owing to stratigraphic hiatus and organism-phylogeny break, we have been discussing the problem without any unitary criterion for several decades. Tectonic ac-tivities occurring strongly in the J-K transitional pe-riod caused commonly sedimentary omissions and frequently volcanic eruptions in northern Hebei Prov-ince, western Liaoning Prov…     

红硕草莓(Senga Sengana)在攀西地区引种试验

在攀西地区引种红硕草莓(Senga Sengana),并进行观察试验,结果表明:红硕草莓(Senga Sengana)适应性强,抗病性也较对照品种“丰香”强;上市早,丰产,长势中等,易栽培管理,生产成本低,适于反季节和元公害栽培; 该品种结果数量多,果个小,果面深红色,果肉桔红色,肉质较硬,符合欧美市场畅销的加工型品种要求。     

西昌市社会经济活动与生态建设的关联分析

利用灰色关联分析方法,从经济生产、社会生产和生态生产角度出发对西昌市社会经济活动与生态环境之间的关系进行了量化研究。研究表明:农业产业的活动是影响水土流失的主要因素,换句话说,调控农业产业经济活动是生态环境维护的有效途径。生态生产、经济生产和社会生产之间存在明显的作用关系,这种作用关系不外乎表现在正作用和负作用两个方面,生态与经济的协调很大程度上依赖于对以上三类要素的合理调节。事实上, 就是利用以上三类生产要素的可塑性,通过产业经济活动的调控,弱化或消除产业与生态的矛盾,积极发展生态产业,这对西昌如此,对其他地区仍具有普遍意义。     

安徽铜陵朝山金矿床稳定同位素、稀土元素地球化学研究

朝山金矿床位于安徽铜陵狮子山矿田，属于矽卡岩型金矿床，侵入岩体为白芒山辉石二长闪长岩体。成矿过程包括矽卡岩阶段、石英-硫化物阶段和碳酸盐阶段3个主要成矿阶段。文章通过对朝山金矿床的氢、氧、碳、硫、硅同位素组成和稀土元素地球化学特征的研究，探讨成矿溶液中水、碳、硅和硫的来源以及成矿溶液的演化问题。研究表明，成矿热液早期以岩浆热液为主，随着成矿过程的进行，加入的大气降水比重越来越大，到晚期可能主要以大气降水为主。该矿床矿石中方解石的碳、氧同位素组成与矿区大理岩的碳、氧同位素组成明显不同，其δ^13 Cv-PDB、δ^18OV-SMOW值分别为-4．5～-5．3‰、13．9～14．0‰，与岩浆作用形成的CO2的碳、氧同位素组成一致，表明矿石中方解石的碳、氧来源于岩浆作用。硅和硫具深部岩浆或岩浆热液来源的特点。     

Variations of δ^18 O in Precipitation along Vapor Transport Paths

Three sampling cross sections along the south path starting from the Tropics through the vapor passage in the Yunnan-Guizhou Plateau to the middle-low reaches of the Yangtze River, the north path from West China, via North China, to Japan under the westerlies, and the plateau path from South Asia over the Himalayas to the northern Tibetan Plateau, are set up, based on the IAEA (International Atomic Energy Agency)/WMO global survey network and sampling sites on the Tibetan Plateau. The variations, and the relationship with precipitation and temperature, of the δ^18 O in precipitation along the three cross sections are analyzed and compared. Along the south path, the seasonal differences of mean δ^18 O in precipitation are small at the stations located in the Tropics, but increase markedly from Bangkok towards the north, with the 51so in the rainy season smaller than inthe dry season. The δ^18 O sovalues in precipitation fluctuate on the whole, which shows that there are different vapor sources. Along the north path, the seasonal differences of the mean δ^18 O in precipitation for the stations in the west of Zhengzhou are all greater than in the east of Zhengzhou. During the cold half of the year, the mean δ^18 O in precipitation reaches its minimum at Uriimqi with the lowest temperature due to the wide, cold high pressure over Mongolia, then increases gradually with longitude, and remains at roughly the same level at the stations eastward from Zhengzhou. During the warm half of the year, the δ^18 O values in precipitation are lower in the east than in the west, markedly influenced by the summer monsoon over East Asia. Along the plateau path, the mean δ^18 O values in precipitation in the rainy season are correspondingly high in the southern parts of the Indian subcontinent, and then decrease gradually with latitude. A sharp depletion of the stable isotopic compositions in precipitation takes place due to the very strong rainout of the stable isotopic compositions in vapor in the process of lifting over the southern slope of the Himalayas. The low level of the δ^18 O in precipitation is from Nyalam to the Tanggula Mountains during the rainy season,but δ^18 O increases persistently with increasing latitude from the Tanggula Mountains to the northern Tibetan Plateau because of the replenishment of vapor with relatively heavy stable isotopic compositions originating from the inner plateau. During the dry season, the mean δ^18 O values in precipitation basically decrease along the path from the south to the north. Generally, the mean δ^18 O in precipitation during the rainy season is lower than in the dry season for the regions controlled by the monsoons over South Asia or the plateau, and opposite for the regions without a monsoon or with a weak monsoon.     

乌鲁木齐市南湖某超市工程场地活断层探测研究

选用了浅层地震、地质雷达探测方法，同时结合微地貌测量、工程地质勘探、地基开挖验证等手段对乌鲁木齐南胡闹市区某超市工程场地及附近的活动断了探层进行测研究。研究结果确定了分布于该区的断层均属雅玛里克断裂带的次级断层，断层数目为5条．对这些断层活动性进行了评价，并对选用探测手段的适应性进行了初步分析和讨论．     

PMOE精密行星历表研究进展

本文扼要介绍了PMOE行星历表研究当前的进展和工作 ,给出了PMOE2 0 0 2与DE40 5历表的比较。