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1.
The vorticity analysis technique was applied to measure the different lithological units,such as schist,metagranite and metavolcano-sedimentary rocks,which are present in the Halaban region.This work aims to interpret the relationship between the different lithologies and the tectonic setting,in order to elucidate the nature of kinematic analysis in the Halaban region.The kinematic analyses were applied to feldspar porphyroclasts,quartz and hornblende for twentysix samples.The kinematic vorticity number (W_m) for deformed rocks in the study area ranged from~0.6 to 0.9.The direction of the long axes for finite strain data (X axes) revealed a WNW trend with shallow dipping.The direction of the short axes for finite strain data (Z axes) were represented by vertical with associated horizontal foliation.The results of the kinematic vorticity and strain analyses are characterized by simple shear with different degrees of deformation in the Halaban region.Furthermore,our finite strain data shows no significant volume change during deformation.The subhorizontal foliation was synchronized with thrusting and deformation.Furthermore,throughout the overlying nappes,the same attitudes of tectonic contacts are observable,the nappes in the orogens being formed from simple shear deformation.  相似文献   
2.
The aim of this study was to investigate biochemical changes in juvenile carp (Cyprinus carpio) exposed to zinc chloride (10, 30 and 100 microM) for a period of 48 h. Zinc exposure caused a concentration-dependent reduction in glutathione reductase (GR) activity in gills, liver and brain. Gill glutathione S-transferase (GST) was reduced when animals were exposed to the highest concentration of 100 microM zinc. The phosphorylation of p38(MAPK) increased in the brain of fish exposed to zinc 100 microM, while phosphorylation of the extracellular signal-regulated protein kinase 1/2 (ERK1/2) and c-Jun N-terminal protein kinase 1/2 (JNK1/2) remained unchanged. Expression of proteins HSP60 and HSP70 were not affected by zinc exposure. Considering the significant concentration-dependent inhibition of GR in all tissues analyzed, this enzyme could be a potential biomarker of exposure to zinc, which has to be confirmed.  相似文献   
3.
自然界矿物、岩石有3000多种,矿物名称很多.也很复杂。许多来地质博物馆参观的观众常会问及矿物名称的问题。其实矿物名称还是有章可循的,只要我们知道矿物的命名方法及一些矿物名称的来源,就对矿物的名称不难掌握了。  相似文献   
4.
5.
当地球发起攻击……   总被引:1,自引:1,他引:0  
四川汶川大地震震惊世界.笔者参阅美国<大众科学>数据,并结合中国、湖南某些地质灾害情况,予以介绍,以飨读者.海啸、火山爆发、地震、山体滑坡--这些大自然杀手的唯一确定的特性是,它们总会卷土重来,一而再,再而三.我们最有效的防御措施是:更有效的预测和保护.  相似文献   
6.
岩石也会"开出"艳丽的花朵.当岩石中有向三度宅问放射生长的矿物品体时,无论把岩石从什么方向剖开,只要断面经过矿物晶体,都会在岩石断面上出现花朵般的图案.如果矿物品体呈柱状, "花瓣"则又细又长,图案好似菊花;如果矿物晶体呈片状, "花瓣"则短而胖,"花朵"就如同攻瑰花.  相似文献   
7.
湖南——世界有色金属之乡   总被引:1,自引:0,他引:1  
湖南地域辽阔、位置优越,邻汉近穗,通江达海。湖湘文化博大精深。有色金属矿产资源丰富多彩,素有"有色金属之乡"之美誉。新矿物层出不穷,震惊世界矿物学界。  相似文献   
8.
地震是一种自然现象,一次强烈地震的发生,常常给人类带来深重的灾难。 四川是多地震的地区,是历史上文化比较发达,经济比较繁荣的地方。大凡破坏性地震发生后,人们为了记事,也为了警觉后人,除作了一些文字记录外,同时树立了不少地震碑石。据江在雄先生在二十多年前的研究和不完全统计,四川境内的地震碑石在七、八个地(州、市)、县共计有几十块,其中90%集中在西昌地区,  相似文献   
9.
Two biodegradation models are developed torepresent natural attenuation of fuel-hydrocarbon contaminants as observed in a comprehensive natural-gradient tracer test in a heterogeneous aquifer on the Columbus Air Force Basein Mississippi,USA.The first, a first-order mass loss model,describes the irreversible losses of BTEX and its individual components, i.e.,benzene(B),toluene(T),ethyl benzene(E),and xylene(X).The second, a reactive pathway model,describe ssequential degradation pathways for BTEX utilizing multiple electron acceptors,including oxygen,nitrate,iron and sulfate,and via methanogenesis.The heterogeneous aquifer is represented by multiple hydraulic conductivity( K) zones delineated on the basis of numerous flowmeter K measurements.A direct propagation artificial neural network(DPN)is used as an inverse modeling tool to estimate the biodegradation rate constants associated with each of the K zones.In both the mass loss model and the reactive pathway model,the biodegradation rate constants show an increasing trend with the hydraulic conductivity.The finding of correlation between biodegradation kinetics and hydraulic conductivity distributions is of general interest and relevance to characterization and modeling of natural attenuation of hydrocarbons in other petroleum-product contaminated sites.  相似文献   
10.
We have obtained velocity-resolved spectra of the 12C II 157.8 microns 2P3/2-2P1/2 fine structure line in the M42 region of Orion. Observations at 0.8 km s-1 resolution with a laser heterodyne spectrometer show multiple velocity components in some locations, with typical linewidths of 3-5 km s-1. Spectra of theta 1C and BN-KL also show weak emission from the F = 2-1 hyperfine component of the equivalent 13C II line. From the observed 12C II/13C II line intensity ratios, we deduce that the 12C II emission is optically thick with tau approximately 5 at both positions. Excitation temperatures of 128 K and 90 K, together with column densities of approximately 1 x 10(19) cm-2 and approximately 4 x 10(18) cm-2, are derived for theta 1C and BN-KL, respectively.  相似文献   
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