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1.
IntroductionTransientElectromagnetic (TEM )techniquehasbeenfurtherstudiedinCanada ,USA ,AustraliaandFormerSovietUnion .Since 1953thefir  相似文献   

2.
瞬变电磁法应用于矿产资源、环境工程等领域.目前主流的瞬变电磁三维正演模拟方法包括积分方程法、有限差分法、有限体积法和有限元法.随着观测环境的复杂化以及探测精度要求的提高,有必要研究瞬变电磁法高精度三维模拟计算,以便推动数据处理解释方法的进步.本文系统介绍了瞬变电磁三维正演计算研究进展,分析了准静态差分方程的构建和发射源...  相似文献   

3.
为了给公路设计部门提供选线依据,运用瞬变电磁法在山西境内的某两条高速公路隧道工程设计线路段上进行探测,以查明下覆不良地质构造的发育情况.通过对瞬变电磁法的探测能力进行理论上的讨论,对不同地电断面情况下的异常体电磁响应的定性分析,得出用瞬变电磁法探测不良地质体的可行性结论.经过资料处理,查出不良地质构造赋存的位置,解释结果与钻探资料完全吻合.  相似文献   

4.
Along with the economic development,large tunnels need to be constructed in many high mountains or complex structure regions,and the design and construction of detailed tunnel exploration become particularly important.Transient electromagnetic method (TEM) uses a non-grounded loop or an electrode to send a primary electromagnetic pulse into the ground,and observes spatial and temporal distribution of secondary electromagnetic field,which is widely applied in mineral resource exploration,engineering geology,etc.The application of TEM in the tunnel construction of Kaiyuan Temple is researched in this study.The smoke loop inversion is adopted for inverting the transient electromagnetic data.The drilling data and high density resistivity method data are combined for comparison.The obtained inversion result greatly coincides with the actual conditions.Therefore,the geophysical prospecting basis can be provided for the division of stratum,delineation of geologi-cal structure,and design and construction of tunnel pavement.By virtue of TEM,drilling data and high density resistivity method,the tunnel construction of Kaiyuan Temple has obtained satisfactory results.  相似文献   

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INTRODUCTIONUrechisanimalsareoftenpresentinH2 Srichseaareawheremostanimalscannotlive .ItcantoleratethestrongtoxicityofH2 S .ManyscholarswereinterestedinthetoleratingmechanismofH2 SintheUrechisanimal (PowellandArp ,1 989;Arpetal.,1 992 ) .Arpetal.(1 992 )indicatedthatthe…  相似文献   

7.
This study on the cytological changes of the body wall ,aspiratory intestine and crissal bursa in Urechis unicincuts by light microscope(LM) and transmission electron microscope(TEM) showed that the difference between the body wall and the natural environment rich in H2S was not obvious,that the wall color of the aspiratory intestine in H2S rich environment changed from normal semitransparency to dark brown.that its epithelia were disassembled and the electron density of its cytoplasm matrix was lower;and that in H2S rich environment many basoplhilic granules occurred in the epithelia of the crissal bursa.Granules with single membrane and myelinefingure were found with TEM.  相似文献   

8.
在透射电子显微镜及环境扫描电子显微镜下观察黄鳍东方鲀精子的超微结构。结果表明:黄鳍东方鲀精子由头部和尾部两部分组成。头部呈长圆柱形,无顶体,核内有小空隙,空隙中有少量电子致密小颗粒存在;核后端正中有凹陷入核内的植入窝,中心粒复合体位于植入窝内,由近端中心粒、中心粒间体和基体组成;袖套位于核的后端,内含线粒体球和含有电子致密物质的小囊泡。尾部细长,自头部后端的正中部向后伸出,近核端部分很短,核心结构是轴丝,鞭毛起始于袖套腔,远核端有侧鳍;轴丝为典型的"9+2"微管对复合体结构。  相似文献   

9.
Estimation of S-wave velocity using logging data has mainly been performed for sandstone,mudstone and oil and gas strata,while its application to hydrate reservoirs has been largely overlooked.In this paper we present petrophysical methods to estimate the S-wave velocity of hydrate reservoirs with the P-wave velocity and the density as constraints.The three models used in this paper are an equivalent model(MBGL),a three-phase model(TPBE),and a thermo-elasticity model(TEM).The MBGL model can effectively describe the internal relationship among the components of the rock,and the estimated P-wave velocities are in good agreement with the measured data(2.8% error).However,in the TPBE model,the solid,liquid and gas phases are considered to be independent of each other,and the estimation results are relatively low(46.6% error).The TEM model is based on the sensitivity of the gas hydrate to temperature and pressure,and the accuracy of the estimation results is also high(3.6% error).Before the estimation,the occurrence patterns of hydrates in the Shenhu area were examined,and occurrence state one(the hydrate is in solid form in the reservoir) was selected for analysis.By using the known P-wave velocity and density as constraints,a reasonable S-wave velocity value(ranging from 400 to 1100 m s~(-1) and for a hydrate layer of 1100 m s~(-1)) can be obtained through multiple iterations.These methods and results provide new data and technical support for further research on hydrates and other geological features in the Shenhu area.  相似文献   

10.
对胜利油田胜坨地区碎屑岩储层岩芯样品和岩石薄晶片分别采用场发射扫描电镜、透射电镜进行镜下观察与能谱测试分析.结果表明:碎屑岩中骨架矿物石英和长石中存在纳米尺度的结构特征;石英镜下可见类蚀像凹坑、雏晶单晶、平行脊线、晶体位错、类包裹体晶内核等5种纳米尺度的结构;长石镜下可见晶面平行凹痕、溶蚀针、纳米级薄层断阶、长石高岭石化、晶体位错和超微包裹体等6种纳米尺度的结构;这些结构大多在几百纳米的尺度范围内,有的甚至只有几十纳米;矿物在纳米尺度上表现出的结构特征与其本身的硬度变化、晶体晶格缺陷、晶体生长过程以及成岩作用的显微表现和显微构造应力改造作用有关.对碎屑岩骨架矿物中纳米尺度结构特征的进一步研究有望为岩石显微变形的应力作用机制和方式以及溶解作用等成岩作用模式做出有效分析,进而为油气勘探开发提供新的探索方式.  相似文献   

11.
1 INTRODUCTION Pit connection is an important feature in Rhodophyta and significant in algal phylogeny. Various documents have illustrated the existence of pit-connection in red alga previously (Migita, 1967; Ramus 1969a, b; Bourne et al., 1970; Lee and F…  相似文献   

12.
详细讨论了电磁波与地震波在介质中的传播规律.根据瞬变电磁测深(TEMS)中心回线装置观测成果与大地电磁测深(MTS)成果的一致性,提出了瞬变电磁资料拟地震解释的思路.大量理论模型的正、反演计算结果表明方法理论是正确的,野外实测资料处理结果进一步说明了该方法的实用性.  相似文献   

13.
The secretion function of mantle is closely related to shell formation in some bivalves and gastropods. Up to now, few researches have been reported for cuttlebone formation in the class Cephalopoda. In this study, the structure and secretion function of cuttlebone sac of the golden cuttlefish Sepia esculenta was analyzed using the histological and histochemical methods. The results showed that high and columnar cells located in sac epithelium, and flat cells existed near the base membrane. A lot of fibroblasts were found in the lateral mantle collective tissue. Some mucus, mucopolysaccharide and alkaline phosphatase (ALP) were found in the sac. The ultrastructural characteristics of Quasi-connective-tissue-calcium cells (QCTCC) were observed using a transmission electron microscope (TEM). The relationship between cuttlebone sac secretion function and shell formation was discussed.  相似文献   

14.
Several papers have reported that part or whole leafy thallus seemingly consisting of zygotospores can give rise to both blades and conchocelis in the same culture of Porphyra. Study on samples of wild and cultivated Porphyra yezoensis and P. oligospermatangia were conducted to clarify the origination of the young blades in the culture. It is confirmed that single cells on the blade of both species, which normally intermixed with zygotospores, germinated into young blades. TEM and SEM observation has shown that the single cells of Porphyra yezoensis had typical features of female gamete (carpogonia) but archeospore. Therefore, the female gametes are responsible in developing leafy thalli.  相似文献   

15.
The pathological changes of hemocytes in the haemolymph and hepatopancreas were examined in experimentally and naturally WSSV (white spot syndrome virus) infected Fenneropenaeus chinensis. The results showed that the pathological manifesta- tions of hemocytes were similar among moribund shrimps infected via injection, feeding and by nature. Firstly, the total hemocyte counts (THCs) in WSSV-infected shrimp were significantly lower than those in healthy shrimp. Secondly, necrotic, broken and dis- integrated cells were often observed, and a typical hematolysis was present in the haemolymph smear of WSSV-infected shrimp. Thirdly, necrosis and typical apoptosis of hemocytes were detected with TEM in the peripheral haemolymph of WSSV-infected shrimp. Hyalinocytes and semi-granulocytes with masses of WSSVs in their nuclei often appeared, whereas no granular bemocytes with WSSV were found in the hepatopancreas of moribund infected shrimps. All our results supported that hemocytes were the main target cells of WSSV, and hyalinocytes and semigranular hemocytes seemed to be more favorable for WSSV infection in F. chinensis.  相似文献   

16.
Histological development of Japanese flounder Paralichthys olivaceus larval skin and ultrastructural difference of skin between reared normal and malpigmented Japanese flounder were studied with light microscopy (LM) and transmission electron microscopy (TEM). The results show that the skin develops slowly before the metamorphosis, while at the onset of metamorphosis, the skin develops quickly and becomes complete in structure till about 50d after being hatched. Ultrastructural observation on the normal and malpigmented skins shows that the iridophore and melanophore are adjacent to each other. Profile and structure of the two kinds of pigment cells are more complete in the skin of normal ocular side than in the skin of pigmented blind side. The ultrastructure of typical chloride cell was observed in the skin of Japanese flounder larvae for the first time.  相似文献   

17.
1 INTRODUCTION Magnetotactic bacteria are able to respond and orient along the direction of terrestrial or artificial magnetic field, a behavior referred to as magneto- taxis. In the majority of magnetotactic bacteria, the magnetosomes are 25–120 nm in d…  相似文献   

18.
Histological development of Japanese flounder Paralichthys olivaceus larval skin and ultrastructural difference of skin between reared normal and malpigmented Japanese flounder were studied with light microscopy (LM) and transmission electron microscopy (TEM). The results show that the skin develops slowly before the metamorphosis, while at the onset of metamorphosis, the skin develops quickly and becomes complete in structure till about 50d after being hatched. Ultrastructural observation on the normal and malpigmented skins shows that the iridophore and melanophore are adjacent to each other. Profile and structure of the two kinds of pigmcnt cells are more complete in the skin of normal ocular side than in the skin of pigmented blind side. The ultrastructure of typical chloride cell was observed in the skin of Japanese flounder larvae for the first time.  相似文献   

19.
哈尔嘎嘎林恩铜金矿床位于西天山阿吾拉勒铁-铜-金多金属成矿带东段,矿区下石炭统艾肯达坂组地层大面积出露,海西晚期闪长岩类分布广泛,NNW向及NW向断裂构造发育。目前已发现的6个铜及铜金矿体均产于艾肯达坂组火山碎屑岩中,主要矿石矿物为黄铜矿、斑铜矿及辉钼矿。钾化、黄铁绢英岩化、青磐岩化等蚀变发育,具斑岩型矿床围岩蚀变典型分带特征。1∶1 000地质-化探剖面测量结果表明,Cu、Au、Mo、Ag等元素含量变化趋势一致且与矿(化)体及钾化蚀变吻合较好;瞬变电磁及磁法测量结果均指示Ⅱ、Ⅲ号矿体SE端深部可能存在隐伏岩体。根据矿床地质、地球化学和地球物理特征,构建了综合找矿模型,并对区内下一步找矿方向进行了预测,认为区内寻找斑岩型多金属矿床的潜力巨大,勘探重点为瞬变电磁高阻异常、正磁异常及化探组合异常叠加区域3 000m标高以下地段。   相似文献   

20.
The non-marine Cretaceous-Paleogene boundary ( KPgB) in Jiayin of Heilongjiang was first defined and reported in China by the authors' research team in 2011 . Thereafter the continuous research on the KPgB and its related Late Cretaceous biota in Jiayin has been made by the authors in 2012-2020 . The achievements of the research are mainly reflected as follows:(1) a new drilling borehole with 60 m in depth carried out in the Xiaoheyan of Jiayin in 2016 , supplemented new palynological evidence for the KPgB definition in 2011;( 2 ) some radiometric dating newly made on the strata related to the KPgB in Jiayin and its neighboring Russian area, provided the supplemental evidence for the KPgB definition in Jiayin;( 3 ) many new fossils found by the au-thors, represented by the angiosperms Dalembia and Nelumbo, refresh understanding the Late Cretaceous envi-ronment of Jiayin;and (4) the TEM method is applied in the study of pollen exine ultrastructure of Pseudoin-tegricorpus, Wodehouseia, and Aquilapollenites, promoting the late Maastrichtian ecological study in Jiayin, re-lated to the KPgB.  相似文献   

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