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1.
陕南震旦系灯影组瓶状微化石研究新进展 总被引：7，自引：0，他引：7
在张录易、李勇（１９９１）初步研究的基础上，作者再次系统采集化石并研究，进一步查明了陕南晚震旦世高家山生物群中瓶状微化石的产出层位、地理分布、宏观特征和属种组合，计有ＰｒｏｔｏｌａｇｅｎａＺｈａｎｇｅｔＬｉ，ｐ．ｇａｏｊｉａｓｈａｎｅｎｓｉｓＺｈａｎｇｅｔＬｉ．Ｐ．Ｐａｐｉｌｌａｔａ（Ｚｈａｎｇ），Ｐ．ｃｙｌｉｎｄｒａｔａ（ｓｐ．ｎｏｖ．）；Ｓｉｃｙｌａｇｅｎａｆｏｒｍｏｓａ（ｇｅｎ．ｅｔｓｐ．ｎｏｖ，），Ｓ．ｌａｔｉｓｔｕｍａ（ｇｅｎ．ｅｔｓｐ．ｎｏｖ．）和一未命名的化石。同时借用电子探针能谱分析和激光分子拉曼微探针等设备对壳壁特征和壳壁物质成分做了尝试性研究，取得较好的效果。 相似文献
2.
三峡库区中侏罗世植物化石及所指示的气候环境 总被引：4，自引：0，他引：4
报道了陈家湾组的植物化石８属１１种（包括１新种）即Ｎｅｏｃａｌａｍｉｔｅｓｓｐ．１,Ｎ．ｓｐ２．Ｐｈｌｅｂｏｔｅｎｓｏｆ．ｐｏｌｙｐｏｄｉｏｄｉｅｓＢｒｏｎｇｎｉａｒｔ,Ｔｈａｕｍａｔｏｐｔｅｒｉｓ,ｓｐ．,Ｃｏｎｉｏｐｔｅｒｉｓｓｉｎｐｌｅｘ（Ｌ．ｅｔＨ．）,ＣｌａｄｏｐｈｌｅｂｉｓｓｈａｎｓｉｅｎｓｉｓＳｚｅ,Ｃ．ｘｉｅｔａｎｅｎｓｉｓＭｅｎｇ（ｓｐ．ｎｏｖ．）Ａｎｏｍｏｚａｍｉｔｅｓｇｒａｃ 相似文献
3.
甘肃迭部早石炭世异珊瑚的发现及Radiciphyllia的微细构造 总被引：1，自引：0，他引：1
本文描述早石炭世异珊瑚类５属６种,包括ＨｅｘａｐｈｙｌｌｉａｆｌｏｒｉｆｏｒｍｉｓＷａｎｇｅｔＹｅ,Ｈｅｔｅｒｏｐｈｙｌｌｉａｔｅｗｏｅｎｓｉｓ（ｓｐ．ｎｏｖ．）,Ｈｅｔｅｒｏｐｈｙｌｌｏｉｄｅｓｃｆ．ｙｕｎｎａｎｅｎｓｉｓ（Ｄｕａｎ）,Ｆｏｓｓｏｐｈｙｌｌｉａｓｐ,,Ｒａｄｉｃｉｐｈｙｌｌｉａｇｉｇａｎｔｅａ（ｓｐ．ｎｏｖ．）．以上标本产自甘肃法部益哇沟、东支沟部面下石炭统大塘价上部,此外Ｒａｄｉｃｉｐｈｙｌｌｉａｓｐ．产自益哇沟下石炭统德坞阶．笔者对Ｒａｄｉｃｉｐｈｙｌｌｉａｇｉｇａｎｔｅａ个体的骨骼微细构造进行扫描电镜研究,其隔壁、横板、外壁均为纤状组织,并由短轴晶柱及晶粒组成．本文还简要讨论Ｒａｄｉｃｉｐｈｙｌｌｉａ的分类位置及其亲缘演化关系． 相似文献
4.
二叠系是广东省的主要产煤地层。阳春地区的上二叠统为阳春组，下二叠统有童子岩组、花园组和栖霞组。童子岩组含煤层；花园组产菊石化石。本文所记述的菊石化石共有４属６种，即Ｐａｒａ－ｇａｓｔｒｉｏｃｅｒａｓｉｒｗｉｎｅｎｓｅ（Ｔｅｉｃｈｅｒｔ），Ｐ．ｃｆ．ａｒｔｏｌｏｂａｔｕｍＲｕｚｈｅｎｃｅｖ，Ｄａｕｂｉｃｈｉｔｅｓｃｆ．ｓｈｏｕｃｈａｎｇｅｎｓｉｓ（Ｃｈａｏ），Ｄ．ｙａｎｇｃｈｕｎｅｎｓｉｓＳｈｅｎｇ（ｓｐ．ｎｏｖ），Ｃｒｉｍｉｔｅｓｃｆ．ｋｒｏｔｏｗｉ（Ｋａｒｐｉｎｓｋｙ），ＰｒｏｓｔａｃｈｅｏｃｅｒａｓｇｕａｎｇｅｎｓｅＳｈｅｎｇ（ｓｐ．ｎｏｖ．）．这在广东尚属首次发现，其时代为早二叠世晚期，相当我国南方早二叠世茅口期早期。本文为在我国南方寻找新的煤田及国内外二叠系的划分和对比提供了新的线索。 相似文献
5.
豫西前寒武纪汝阳群遗迹化石 总被引：18，自引：3，他引：18
本文研究的遗迹化石：Ｒｕｙａｎｇｉｃｈｎｕｓ ｌｏｙｕｅｎｓｉｓ ｉｃｈｎｏｇｅｎ，ｅｔ ｉｃｈｎｏｓｐ．ｎｏｖ．，Ｔｏｒｒｏｗａｎｇｅａ ｒｏｓｅｉ ｗｅｂｂｙ，Ｃｈａｎｇｃｈｅｎｇｉａ ｉｃｈｎｏｓｐ．，Ｓｑｕａｍｏｄｉｃｔ ｙｏｎ（？）ｉｃｈｎｏｓｐ．等发现于河南西部鲁山县和汝阳县的汝阳群云梦山组和北大尖组。根据同位素年龄值，微古植物和叠层石资料，产遗迹化石的汝阳群应相当于中元古代，可以和蓟 相似文献
6.
本文描述异珊瑚标本采自贵州威宁老桥下石炭统上司组,包括２属７种,其中新种４个及３个未知种,新种有：Ｈｅｘａｐｈｙｌｌｉａｌａｏｑｉａｏｅｎｓｉｓｓｐ．ｎｏｖ．Ｈ．ｃｒａｓｓｉｅｐｔａｓｐ．ｎｏｖ．Ｈ．ａｂｎｏｒｍｉｓｓｐ．ｎｏｖ．ｈ．ｗｅｉｎｉｎｇｅｒｓｉｓｓｐ．ｎｏｖ。 相似文献
7.
三种裸子植物化石木的研究 总被引：3，自引：0，他引：3
本文研究了我国长江北岸湖北省武汉市新洲肥阳逻辑北部晚第三纪的三种裸子植物化石木，它们是水松ＧｌｙｐｔｏｓｔｂｕｓｐｅｎｓｉｌｉｓＫ．Ｋｏｃｈ，武汉柏木ＧｕｐｒｅｓｓｕｓｗｕｈｎｎｅｎｓｉｓＪ．Ｊ．Ｙａｎｇｓｐ．ｎｏｖ。和武汉刺柏ＪｕｎｉｐｅｒｕｓｗｕｈａｎｅｒｓｉｓＪ．Ｊ．Ｙａｎｇｓｐ．ｎｏｖ这些化石木的发现，给研究我国裸子植物提供了良好的依据，此外，对１９９０年发表于《林业科学》（２６卷４期）上 相似文献
8.
从牙形石论关岭动物群的时代 总被引：9，自引：0，他引：9
牙形石是关岭动物群的重要组成门类之一,本文通过对关岭县黄土塘附近产该动物群瓦窑组部底部牙形石的初步研究,获得非常丰富的似舟刺属（ｐａｒａｇｏｎｄｏｌｅｌｌａ）的分子,并对其中的Ｐ．ｘｉｎｐｕｅｎｓｉｓ（ｓｐ．ｎｏｖ）,Ｐ．ｗａｙａｏｅｎｓｉｓ（ｓｐ．ｎｏｖ）２个新种进行了描述;划分出Ｐ．ｐｏｌｙｇｎａｔｈｉｆｏｒｍｉｓ带;根据Ｎｅｏｇｏｎｄｏｌｅｌｌａ－ｅｘｃｅｌｓａ类族演化谱系和地层对比等,认为 相似文献
9.
10.
桐柏蔡家凹岩片内寒武纪高肌虫的发现及其地质意义 总被引：5，自引：0，他引：5
本文描述了河南桐柏西北部蔡家凹大理岩岩丰富的高肌虫化石Ｔｏｎｇｂａｉｅｌｌａ ｘｉｎｊｉｅｎｓｉｓ ｇｅｎ．ｅｔ ｓｐ．ｎｏｖ．、Ｘｉａｎｚｈｅｅｌｌａ ｈｅｎａｎｅｎｓｉｓ ｓｐ．ｎｏｖ．和Ｍｏｎｏｎｏｔｅｌｌａ ｃｆ．ｃｈｕａｎｓｈａｎｅｎｓｉｓ Ｈｕｏ ｅｔＳｈｕ及小壳化石Ｃｏｎｏｔｈｅｃａ ｓｐ．共有４属４种。据此确定含化石地层为寒武系,属浅海沉积环境。该生物群的发现为解决桐柏大别造山带与 相似文献
11.
E. M. Prasolov S. A. Sergeev B. V. Belyatsky E. S. Bogomolov K. A. Gruzdov I. N. Kapitonov R. Sh. Krymsky V. O. Khalenev 《Geochemistry International》2018,56(1):46-64
This paper reports the first results of a study of 11 isotope systems (3He/4He, 40Ar/36Ar, 34S/32S, 65Cu/63Cu, 62Ni/60Ni, 87Sr/86Sr, 143Nd/144Nd, 206–208Pb/204Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others. 相似文献
12.
Mining induced subsidence can significantly affect mining costs where major surface facilities and natural environment need to be protected. Overburden grout injection is a technology used to control coal mine subsidence by injecting the mine waste material extracted from the coal back into the inter-burden rock during longwall mining. The flowing slurry is here categorised as a nonlinear viscous cohesive (Bingham plastic) fluid. During longwall mining the grout slurry is pumped into the separated beds of the rock mass through a central vertical borehole, which is drilled deep into the inter-burden rock strata above the coal seam. However, a blockage can occur in the injection system when the slurry velocity falls below a certain critical threshold velocity, indicating a material phase change from cohesive-viscous to cohesive-frictional. In situ field injection tests through boreholes have been simulated at a smaller scale at the CSIRO laboratory in Brisbane by pumping the slurry through a radial disk (gap = 4 mm) from its centre. Laboratory experiments indicate a general, nonlinear, cohesive, viscous, frictional model for shear behaviour of the slurry, in which the material shear parameters are functions of the disk radial distance. Complete dimensional and dimensionless analytical solutions have been developed based on an approach related to Bingham–Herschel–Bulkley fluid mechanics. The derived formulae include relations for minimum pump pressure, local pressure and pressure gradient, wall shear stress, volume rate, velocity and velocity gradient. The theoretical results match the experimental measurements. The experiments covered slurries with maximum particle sizes of 0.5 to 2 mm with about 50% being larger than 100 µm. The viscosities at the various solids concentrations were measured with a standard torsion viscometer. This study differs from the previous research in several distinct aspects, namely, consideration of the variable shear parameters rather than fixed values, inclusion of total nonlinear behaviour, and implementation of a friction function to mimic behaviour of the deposited and consolidating stiff slurry, which can cause a significant pressure rise as a result of the increased shear resistance. 相似文献
13.
S. Viswanathan K. Surya Prakash Rao B. Mahabaleswar 《Journal of the Geological Society of India》2013,82(6):621-627
Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours. 相似文献
14.
15.
Marta L. PATINO-DOUCE Alberto PATINO-DOUCE Mazhar QAYYUM Roger L. NIELSEN 《Geostandards and Geoanalytical Research》1994,18(2):195-198
We have developed a set of four synthetic standards for the rare earth and high field strength elements designed for use in the determination of those elements in silicates. The base material is a glass nominally at the eutectic of the MgO-Al2 O3 -SiO2 ternary system. The nominal doping level was 2 wt% of the elements as oxides. To avoid problems associated with peak interference, the elements were doped in four separate glasses. 相似文献
16.
Alexander E. C. Broberg J. S. Kehren A. R. Graziani M. M. Turri W. L. 《Environmental Geology》1993,22(4):353-361
Bellechester, Minnesota, is a small community of approximately 155 residents located on the county line between Goodhue and Wabasha counties in southeast Minnesota's karst region. Bellechester is served by a 21-year-old wastewater treatment facility (WWTF) consisting of three waste-stabilization ponds. On 28 April 1992 six sinkholes were discovered to have drained cell 2 of the WWTF resulting in the loss of approximately 8.7×106 1 of partially treated effluent and about 600 m3 of soil into previously undetected subsurface voids of unknown dimensions. In the week following the collapse, approximately 200 water wells located within a 5-km radius of the WWTF were sampled in an after-the-fact, emergency sampling program. Twelve samples with elevated fecal coliform levels, 18 samples with nitrate-nitrogen greater than the 10 mg/1 standard, and no samples with elevated chlorides were found. However, the elevated levels could not be unambiguously attributed to the WWTF collapse. This is the third WWTF to fail by sinkhole collapse in southeast Minnesota since 1974. All three collapsed lagoons have been located in similar geomorphic and stratigraphic settings. However, at least two lagoons have collapsed in the adjacent area in northeast Iowa, and these lagoons are located at different stratigraphic positions. Twenty-two WWTFs constructed in southeast Minnesota's karst region in the last 25 years have been identified as subject to potential sinkhole collapse. An unknown but significant number of manure storage lagoons, flood control structures, etc., have also been constructed in the karst region and are at risk. Public agencies are beginning to develop plans to deal with the risk associated with existing and future waste lagoons in this environment. The critical hydrogeologic parameters that can be used to prioritize the risk of collapse at existing facilities include: (1) the lithology of the first bedrock beneath each lagoon, (2) the thickness of surficial materials between the lagoon and the bedrock surface, (3) the presence and construction of liners (seepage rate), and (4) the proximity to existing sinkholes. 相似文献
17.
Between 1985 and 1991, two new mountain protected areas (MTNPA) covering more than 35,000 km2 and based on participatory management models — the Makalu-Barun National Park and Conservation Area, Nepal, and Qomolangma Nature Preserve, Tibet Autonomous Region — were successfully established through the collaborative efforts of Woodlands Mountain Institute and conservationists in China and Nepal. Characteristics common to both projects include the importance of establishing (1) effective rationales, (2) local support constituencies, (3) a senior advisory group, (4) a task force, (5) linkages between conservation and development, and (6) fund raising mechanisms. The lessons derived from the experiences of Woodlands Mountain Institute are of significant value to others in preserving MTNPA. Increased collaboration and communication between all interested in conservation, however, will remain a critical component for expanding mountain protected area coverage to throughout the world. 相似文献
18.
Mercury,arsenic, antimony,and selenium contents of sediment from the Kuskokwim River,Bethel, Alaska,USA 总被引：1，自引：0，他引：1
The Kuskokwim River at Bethel, Alaska, drains a major mercury-antimony metallogenic province in its upper reaches and tributaries. Bethel (population 4000) is situated on the Kuskokwim floodplain and also draws its water supply from wells located in river-deposited sediment. A boring through overbank and floodplain sediment has provided material to establish a baseline datum for sediment-hosted heavy metals. Mercury (total), arsenic, antimony, and selenium contents were determined; aluminum was also determined and used as normalizing factor. The contents of the heavy metals were relatively constant with depth and do not reflect any potential enrichment from upstream contaminant sources. 相似文献
19.
Susan E. Hogg 《Earth》1982,18(1):59-76
Following McGee's (1897) use of the term sheetflood, there developed a variety of conflicting opinions and numerous terminologies relating to this process, many of which are ill-considered and poorly defined. A classification system is devised on both a hydrologic and geomorphic basis which dispenses with many superfluous terms that have been used with respect to sheetfloods. Magnitude of a storm is expressed in terms of the amount of surface runoff generated from a given storm due to the surface conditions.A sheetflood is defined as a sheet of unconfined flood water moving down a slope. The frequency of a sheetflood is relatively low while its magnitude is relatively great. Sheetflow is defined as relatively high-frequency, low-magnitude overland flow occurring in a continuous sheet and is restricted to laminar flow conditions. Sheetwash, a term of geomorphic origin, is considered to be redundant and is superseded by the more meaningful term rainwash defined as the washing action of rain on slopes. 相似文献
20.
Mass Fractions of S,Cu, Se,Mo, Ag,Cd, In,Te, Ba,Sm, W,Tl and Bi in Geological Reference Materials and Selected Carbonaceous Chondrites Determined by Isotope Dilution ICP‐MS 
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下载免费PDF全文 Zaicong Wang Harry Becker Frank Wombacher 《Geostandards and Geoanalytical Research》2015,39(2):185-208
Mass fractions of S, Cu, Se, Mo, Ag, Cd, In, Te, Ba, Sm, W and Tl were determined by isotope dilution sector field ICP‐MS in the same sample aliquot of reference materials using HF‐HNO3 digestion in PFA beakers in pressure bombs and glassy carbon vessels in a high‐pressure asher (HPA‐S) for comparison. Additionally, Bi was determined by internal standardisation relative to Tl. Because isobaric and oxide interferences pose problems for many of these elements, efficient chromatographic separation methods in combination with an Aridus desolvator were employed to minimise interference effects. Repeated digestion and measurement of geological reference materials (BHVO‐1, BHVO‐2, SCo‐1, MAG‐1, MRG‐1 and UB‐N) gave results with < 5% relative intermediate precision (1s) for most elements, except Bi. Replicates of NIST SRM 612 glass digested on a hot plate were analysed by the same methods, and the results agree with reference values mostly within 2% relative deviation. Data for the carbonaceous chondrites Allende, Murchison, Orgueil and Ivuna are also reported. Digestion in a HPA‐S was as efficient as in pressure bombs, but some elements displayed higher blank levels following HPA‐S treatment. Pressure bomb digestion yielded precise data for volatile S, Se and Te, but may result in high blanks for W. 相似文献