叠溪地震的今昔--为建立叠溪地质公园进言   总被引：3，自引：0，他引：3  

周绪纶 《四川地质学报》2003,23(3):188-192

1933年8月25日的叠溪大地震，产生了众多的地震效应现象，如陷落槽、地震湖等。地震湖的震后效应尤为深远，在其后60多年溃堤了4次，给湖下游人民的生命财产造成严重损失。而各种地震遗迹独具特色，尤其是大小海子湖妩媚的湖光山色及众多的陷落槽等现象，具有很高的科考和旅游价值。笔者对建立叠溪地质公园提出了建议。  相似文献   

信息化施工技术在保护某厂濒危烟囱中的应用     

张子清 《上海国土资源》2003,(2):59-62

通过地处上海某厂锅炉房濒危烟囱北侧仅5米处的实验楼基础施工，详尽介绍了施工过程中保护濒危烟囱的防护工程对策，以及采用信息化施工技术而取得的良好经济效益。  相似文献   

软土结构性破损的孔径分布试验研究   总被引：6，自引：1，他引：6  

吕海波  汪稔  赵艳林  孔令伟 《岩土力学》2003,24(4):573-578

采用压汞法对天然结构性软土压缩过程孔隙大小分布的演化进行了试验研究，结果表明，当荷载超过结构屈服应力后，尺寸较大的团粒间孔隙首先发生破坏，随着荷载的增大，越来越小的孔隙受到影响，但团粒内孔隙在压缩过程中不发生变化；根据试验结果提出了孔隙结构破损势的概念，并用其表征孔隙分布随荷载变化的规律。  相似文献   

湖北省南漳县红星磷矿磷块岩特征与物质组分研究     

黄青山  朱薇 《化工矿产地质》2003,25(3):179-184

湖北省南漳县震旦系沉积型红星磷矿矿体P_2O_5平均含量23.91%,矿石自然类型主要为角砾状磷块岩,其次为白云质磷块岩、泥质纹层状和条带状致密块状磷块岩。工业类型主要为钙(镁)质和硅钙(镁)质磷矿,其次为硅质磷矿。矿石矿物为胶状磷灰石和微晶磷灰石,经x-射线衍射物相分析,其种属为含碳氟磷灰石。嵌布粒度以细-中粒为主。脉石矿物主要为白云石、伊利石、高岭石、铁质。经测定当磷块岩磨矿粒度小于0.1mm,其磷酸盐矿物单体解离率可达92.53％,这为确定合理的选矿流程具有实际意义。  相似文献   

Noble Gases in the Lunar Regolith     

邹永廖  徐琳  欧阳自远 《中国地球化学学报》2003,22(4):361-368

The most fundamental character of lunar soil is its high concentrations of solar-wind-implanted elements, and the concentrations and behavior of the noble gases He, Ne, Ar, and Xe, which provide unique and extensive information about a broad range of fundamental problems. In this paper, the authors studied the forming mechanism of lunar regolith, and proposed that most of the noble gases in lunar regolith come from the solar wind. Meteoroid bombardment controls the maturity of lunar soil, with the degree of maturation decreasing with grain size; the concentrations of the noble gases would be of slight variation with the depth of lunar soil but tend to decrease with grain size. In addition, the concentrations of noble gases in lunar soil also show a close relationship with its mineral and chemical compositions. The utilization prospects of the noble gas ^3He in lunar regolith will be further discussed.  相似文献   

钻孔灌注桩在某工程中的应用及质量控制     

张浩罡 《上海国土资源》2003,(3):30-32

作为地下隐蔽工程的钻孔灌注桩其质量的好坏直接影响到上部构、建筑物的使用质量和安全,从成孔到灌注成桩其工艺复杂且环环相扣,相互制约又相互影响。文章从影响成桩质量的几个要点,着重分析和阐述了保证灌注质量的措施和方法。  相似文献   

钾-氩和氩-氩定年样品的送样要求及预处理   总被引：11，自引：1，他引：11  

刘玉琳苗国均  黄宝玲 《岩矿测试》2003,22(4):297-299

介绍了K-Ar和Ar-Ar法定年样品的送样要求及实验室预处理程序，样品粒度以250～180μm为宜；用量则视样品的K含量和年龄情况而定，K含量越高、年龄越老，所需样品量越少，多数样品的用量在几十至几百毫克；对于年龄情况不清楚的样品，10～20g手标本或者1～2g合适粒度的样品可以保证用量。全岩样品常受蚀变和捕虏晶的影响，有效的预处理可以在很大程度上消除这些干扰因素。文章还介绍了用稀HNO3消除碳酸盐、1．7mol／L HF消除轻微蚀变的影响以及电磁选剔除捕虏晶的实验过程。  相似文献   

高压下玄武岩浆的不混溶及其对双峰式火山岩的成因意义   总被引：2，自引：4，他引：2  

郑海飞　陈斌孙樯  谢鸿森 《岩石学报》2003,19(4):745-751

我们在温度850～1300℃,压力1.0～3.0GPa和含约2%水的条件下的碱性玄武岩熔融实验产物中发现在高于2.0GPa压力下玄武岩熔融后的淬火产物中存在着两种不同成分的玻璃,其中一种呈褐色,另一种为浅色或无色.玻璃的电子探针分析结果表明,褐色玻璃具有相对高的MgO、FeO和相对低的SiO2、K2O、Na2O含量及Na2O＞K2O的特征.熔体的不混溶间隙与温度无明显关系,但与压力关系密切,即在大于2.0GPa的压力条件下两种玻璃的不混溶间隙突然增大.因此,由不混溶作用形成的双峰式火山岩应来自大于2.0GPa的上地幔,且是能够提供酸性端员物质以及快速上升的构造环境.这与双峰火山岩可以产生于大陆裂谷环境或主要产于俯冲带的弧后拉张环境而不是岛弧前缘一致.  相似文献   

柯坪塔格推覆构造几何学、运动学及其构造演化   总被引：29，自引：1，他引：29  

曲国胜  李亦纲  陈杰  宁宝坤  李岩峰  李军  尹军平 《地学前缘》2003,10(Z1):142-152

大量野外构造地质调查和深部构造解释表明柯坪塔格推覆构造由多组倒转复式背斜、复式箱状背斜构成的推覆体及其前缘逆冲断裂组成 ,由寒武系—第四系组成的推覆体由北向南逆—斜冲 ,平面上构成向南凸出的弧形推覆构造 ;普昌断裂由各不相连的逆冲斜冲断裂段组成 ,而不是完整的一条走滑断层 ,各推覆体前缘逆冲断裂与各推覆体的普昌断裂段共同构成统一的前缘逆冲斜冲逆冲断裂和推覆构造系统 ;普昌断裂段以西的推覆体具有向东抬升、向西倾覆的鼻状构造特征 ,普昌断裂段以东的推覆体具有向西抬升、向东倾覆的鼻状构造特征 ,普昌基底隆起带是巴楚隆起隐伏在柯坪塔格推覆构造之下的部分。各推覆体前缘断裂在深部均归并于统一的寒武系底部的滑脱面 ,其南浅北深 ,东浅西深 (普昌隆起带以西 )或西浅东深 (普昌隆起带以东 ) (6 10km ) ,埋深较大区发育多组滑脱面。柯坪塔格推覆构造的形成时期为晚第四纪 ,为现今活动的推覆构造系统。文中认为各推覆体向南西的倾覆端基底滑脱面和中新生界内部的滑脱面没有贯通 ,是未来 6级以上地震的发震构造部位。  相似文献   

The development of Nemurella pictetii Klapálek (Plecoptera: Nemouridae) in two springstreams in central Europe     

Andrei Nesterovitch  Peter Zwick   《Limnologica》2003,33(4):231-243

From April 1997 to June 1998 Nemurella pictetii populations were regularly sampled in two springstreams at 220 and 850 m a.s.l., respectively, in Hesse (Germany), at approximately 51°N. Random samples of larvae were taken at three week intervals during the vegetation period, and once a month during winter. Sex, instar, body length, head capsule width and wing pad length of all larvae were recorded. Temperatures were recorded every hour, temporal patterns of temperature agreed closely between sites. Mean winter lows were 3.9 °C at both sites, the mean summer high was 11.9 °C at the lower site, as opposed to 9.6 °C at the mountain site.At both sites, adult emergence started in May. At the mountain site, recruitment started in late July and continued into autumn. There was cohort splitting in the young generation. Some individuals grew rapidly until October–November, but last instar larvae first appeared in March the next year. 1600 degree-days above 0 °C were accumulated during complete development. At the lower site, recruitment began in early July, and cohort splitting also occurred. Fast growing summer recruits emerged as adults in late August, having accumulated only 700 degree-days (above 0 °C). Their offspring hatched in November-December and emerged the next spring, having accumulated also only 700 degree-days. However, only part of the population was bivoltine. Many of the summer recruits grew more slowly and accumulated close to 1900 degree days until they emerged the next spring, together with the offspring of their own fast-growing siblings. Dependence of growth rate on temperature could not be estimated and appears to vary with daylength. For example, 3–6 °C support growth and development provided daylength exceeds 10 hrs of light, or is rising.At both sites and in all cohorts individuals emerging earliest were larger than later emerging ones. The size decline is significantly correlated with number of days after the winter solstice. For the first time it is shown that the decline does not occur shortly before adult emergence but actually takes place several instars before the last. Size differences are then carried on, and amplified, during subsequent molts, until adulthood. The literature presently relates seasonal size declines of insects to high or rising temperatures experienced by larvae approaching adulthood. Our data show that, at least in Nemurella, this explanation fails. On average, females were distinctly larger than males. Differences in mean last instar size were noticed also between sites and years. They remain presently unexplained. The mean sex ratio in both populations was close to 1:1.  相似文献