克拉玛依蛇绿混杂岩带的基本特征和锆石SHRIMP年龄信息

新发现的克拉玛依蛇绿混杂岩带分布于准噶尔盆地西北缘,表现为组分齐全的蛇绿岩和增生杂岩。由盆地边缘向山区方向,大体呈依次带状分布的超镁铁质岩、镁铁质岩、枕状玄武岩和深海相硅质岩,同时发现超镁铁岩之上被一套火山磨拉石沉积不整合覆盖。在克拉玛依蛇绿岩的白碱滩段中采得蚀变辉长岩样品,锆石SHRIMP定年结果集中在(414.4 8.6)Ma和(332±14)Ma。这一发现为研究中亚洋盆形成和消亡时代提供了重要依据,也为确定准噶尔盆地基底性质提供了重要线索。     

Implications of the Precambrian Non-stromatolitic Carbonate Succession Making up the Third Member of Mesoproterozoic Gaoyuzhuang Formation in Yanshan Area of North China

A particular non-stromatolitic carbonate succession making up the third member of the Mesoproterozoic Gaoyuzhuang (高于庄) Formation might demonstrate that a stromatolite decline of the Mesoproterozoic occurring at ca. 1 450 Ma besides other three events of the Proterozoic,respectively,occurred at ca. 2 000 Ma,ca. 1 000 Ma,and ca. 675 Ma. The forming duration of this non-stromatolitic carbonate succession can be generally correlative to that of a similar depositional succession in North America,i.e. a non-stromatolitic carbonate succession made up by the Helena Formation of the Belt Supergroup,which suggests that the stromatolite decline occurring at ca. 1 450 Ma may be a global event. This information endows the non-stromatolitic carbonate succession making up the third member of the Gaoyuzhuang Formation in the Yanshan (燕山) area with important significance for the further understanding of Precambrian sedimentology. The Mesoproterozoic Gaoyuzhuang Formation in Yanshan area is a set of more than 1 000 m thick carbonate strata that can be divided into four members (or subformations). The first member (or the Guandi (官地) subformation) is marked by a set of stromatolitic dolomites overlying a set of transgressive sandstones; the second member (or the Sangshu'an (桑树鞍) subformation) is a set of manganese dolomites with a few stromatolites; the third member (or the Zhangjiayu (张家峪) subformation) is chiefly made up of leiolite and laminite limestones and is characterized by the development of molar-tooth structures in leiolite limestone; the fourth member (or the Huanxiusi (环秀寺) subformation) is composed of a set of dolomites of stromatolitic reefs or lithoherms. Sequence-stratigraphic divisions at two sections,i.e. the Jixian (蓟县) Section in Tianjin (天津) and the Qiangou (千沟) Section of Yanqing (延庆) County in Beijing (北京),demonstrate that a particularly non-stromatolitic succession making up the third member of the Mesoproterozoic Gaoyuzhuang Formation is developed in the Yanshan area of North China,in which lots of grotesque matground structures (wrinkle structures and palimpsest ripples) are developed in beds of leiolite limestone at the Qiangou Section and lots of molar-tooth structures are developed in beds of leiolite limestone at the Jixian Section. The time scale of the Gaoyuzhuang Formation is deduced as 200 Ma (from 1 600 Ma to 1 400 Ma). The duration of an obvious hiatus between the Gaoyuzhuang Formation and the underlying Dahongyu (大红峪) Formation is deduced as 50 Ma to 100 Ma,thus the forming duration of the GaoyuzhuangFormation is thought as 100 Ma (1 500 Ma to 1 400 Ma). Furthermore,the age of the subface of the third member of the Gaoyuzhuang Formation that is just in the mid position of the Gaoyuzhuang Formation can be deduced as about 1 450 Ma,which is the basis to infer a stromatolite decline of the Mesoproterozoic occurring at ca. 1 450 Ma. Importantly,several features of both the molar-tooth structure and the stromatolite,such as the particular forming environment,the important facies-indicative meaning,and the episodic distribution in the earth history,might express the evolutionary periodicity of the surface environment of the earth and can provide meaningful clues for the understanding of the Precambrian world,although their origin and forming mechanism is highly contentious. Therefore,like other three stromatolitic declines,respectively,occurring at ca. 675 Ma,ca. 1 000 Ma,and ca. 2 000 Ma,the identification of the stromatolite decline occurring at ca. 1 450 Ma during the Golden Age of stromatolites (2 800 Ma to 1 000 Ma) has important meaning for the further understanding of the evolving carbonate world of the Precambrian.     

广西厚皮甜瓜气候条件分析

针对厚皮甜瓜生产的气象条件，结合广西的气候特点，提出广西厚皮甜瓜生产的气候条件分析，为厚皮甜瓜在广西的生产发展提出一些建议。     

青藏高原东北部史前人类生存策略的区域差异及其影响因素

青藏高原不同海拔区域生存策略存在显著差异,相关研究对于揭示人类对高原极端环境的适应进程有重要意义.已有研究从不同视角和方法对青藏高原东北部生存策略进行了探讨,但对青藏高原东北部不同海拔区域间的生存策略差异及其影响研究仍较薄弱,尤其以数理模型开展生存策略的研究尤为缺乏.本文运用迈阿密模型,估算得出区域气候生产潜力的分布状...     

AutoCAD在防雷设计中的常用技巧

介绍AutoCAD防雷设计图通过OLE对象直接粘贴、屏幕拷贝功能和画图程序转换图片、Export功能转换通用图片、Plot功能转换通用图片4种方式与Microsoft Word软件间进行数据交流的技巧,及4种方法的优缺点,介绍在AutoCAD绘图环境下如何利用Microsoft Excel软件快速制作表格;对AutoCAD在防雷设计图中存在的版本不兼容、文字乱码、错误图形文件3个常见问题作了分析,并给出了解决办法。     

厄尔尼诺与恩平气候

统计并分析了广东省恩平市气象站建站以来厄尔尼诺发生年的一些主要气象要素变化和天气事件出现机率，发现厄尔尼诺年恩平气候出现多个气候之最，说明厄尔尼诺现象可造成多种气候异常，而对恩平气候的影响主要体现在极端高温与极端低温天气增多，年降水偏多，且主要集中在汛期，暴雨及大暴雨、冰雹等强对流天气次数增多，秋冬春连旱机率较大，台风个数偏少，但每隔3—5个厄尔尼诺年就会有强台风影响。     

太平洋混合层厚度(dml)年际异常的初步分析

用太平洋区域30a逐月混合层厚度(dml)及浅层海温(Ts)距平资料,分析了20°S以北太平洋区域dml年际变率的地理分布和季节变化,得到两个纬向dml高变率带,它们分别位于北太平洋(45°N附近)和赤道中、西太平洋.重点分析了赤道太平洋dml高变率带,并对其上混合层气候位置、dml年际异常与El Nino事件关系及伴随强El Nino事件的dml正异常东传等作了初步分析.     

壳聚糖希夫碱铜配合物的制备及其催化性能

采用微波辐射加热法使壳聚糖与水杨醛反应生成壳聚糖希夫碱,然后将其与铜盐配位得到壳聚糖希夫碱铜配合物,用UV、FTIR、TG表征产物的结构,并探讨该配合物对过氧化氢分解的催化性能。研究结果表明:壳聚糖希夫碱铜配合物对过氧化氢有良好的催化活性,常温(25℃)常压,pH=7.0的条件下放置12 h,催化H2O2的分解达99.8%,该配合物重复使用3次还保持较好的催化活性。     

青海省贵德县(盆地)地热资源的开发利用

本文以贵德盆地地热地质条件为背景,结合贵德盆地多年的地热探采积累的资料,论述该盆地地热资源赋存特点,并对地热成井工艺和对地热的合理的开发利用提出了见解,对类似山间盆地地热资源的开发利用具有一定的借鉴意义。