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1.
依据GertaKeler和Gasperi,Kennett有关中新世印度洋和太平洋浅层水、中层水和深层水浮游有孔虫深度分层组合的划分模式,对南海琼东南盆地崖19-1-1井晚第三纪浮游有孔虫作了定量研究,并分析了陆架海区浮游有孔虫不同深度分层组合含量的变化与古地理环境变迁的关系。崖19-1-1井以浅层水、中层水组合为主,深层水组合不发育,反映本区温跃层不发育,不利深层水浮游有孔虫的生存。滨海区,浮游有孔虫仅为少数几个浅层水的优势种,中层水浮游有孔虫不发育;内浅海区,浅层水浮游有孔虫占绝对优势,中层水浮游有孔虫处于次要地位,所含比例相对较小;外浅海区及陆坡半深海区,浅层水和中层水浮游有孔虫均较发育,中层水浮游有孔虫百分含量相对较高。崖19-1-1井在上新世早中期曾出现外浅海至陆坡半深海区,为古水深最大时期  相似文献   

2.
International carbon and oxygen isotope calibration material NBS 19 and reference materials NBS 18, International Atomic Energy Agency (IAEA)-CO-1 and IAEA-CO-8 are prepared from naturally occurring rock specimens of marble and carbonatite. Mineralogical and chemical analysis showed that only NBS 19 and IAEA-CO-1 represent essentially pure samples of calcite containing < and minimal (< 1%) quantities of quartz. In contrast, both NBS 18 and IAEA-CO-8, although primarily composed of calcite, are contaminated by a range of additional phases. NBS 18 was estimated to contain 1% Fe-dolomite and trace (< 1%) quantities of apatite and quartz. IAEA-CO-8 was estimated to contain at least 4% non-carbonate material (including apatite, barite, biotite and magnetite). NBS 18 and IAEA-CO-8 are both derived from samples of carbonatite and the calcite component of each material is characterised by appreciable substitution of Mg + Mn + Sr ± Fe ± Ba (Σ ≈ 14000–15000 μg g-1) for Ca. The observations reported in this study complement data in the literature detailing significant grain-scale isotopic heterogeneity in NBS 18 and IAEA-CO-8. Both data sets highlight the need for careful characterisation of calibration materials prior to distribution.  相似文献   

3.
南海珠江口盆地LH-19-4-1井新近纪有孔虫生物地层研究   总被引:3,自引:1,他引:2  
标准化石的末现面(LAD)被广泛用于全球性地层划分和对比,但是,只有像白垩纪与第三纪之间的撞击事件所引起的全球性生物集群绝灭(LAD)才具有全球等时间的性质。标准浮游有孔虫化石带的LAD,可能与白垩纪与第三纪之间的撞击事件所引起的LAD一样、具有全球等时面的性质,所以它可以用于全球地层的划分和对比。依据标准浮游有孔虫带的研究,南海珠江口盆地LH-19-1-1井的岩屑地层(430m-2 630m)一共识别出20个带(N_(22)-N_3)。更新世:N_(22)带(430m-620m);晚上新世:N_(21)-N_(20)带(620m-680m);早上新世:N_(19)-N_(18)带(680m-790m);晚中新世:N_(17)-N_(16)带(790m-1 139m);中中新世:N_(15)-N_8带(1 139m-1 898m);早中新世:N_7-N_4带(1 898m-2 588m);晚渐新世:N_3带(2 588m-2 630m)。它们可以和世界其他地区的地层作准确的对比。  相似文献   

4.
Instrumental neutron activation data on 19 trace elements in two new geostandards, Bottom Silt from Lake Baikal, BIL-1 and Brown Coal Ash, ZUK-1 are presented.  相似文献   

5.
Two types of gold deposit with both good homogeneity and a high-grade of gold were selected to prepare four gold ore reference materials (GAu-19,GAu-20,GAu-21 and GAu-22) by the Institute of Geophysical and Geochemical Exploration (IGGE),China.Seven laboratories participated in the certification programme. Volumetric methods for GAu19-21 and atomic absorption spectrometry for GAu-22 were used for the homogeneity testing,the coefficient of variation being found to be less than 3%.After sample digestion and preconcentration,the samples were analysed by flame atomic absorption spectrometry (AAS),colorimetry,neutron activation analysis (NAA)and volumetric analysis. The certified values for the gold concentration in GAu19-22 are 18.3 μg g -1, 32.3 μg g -1, 53.0 μg g -1 and 5.72 μg g -1,respectively.  相似文献   

6.
Micropalaeontological investigation of samples from Scott Reef No. 1 has revealed a thick Cainozoic carbonate sequence. Rich planktonic faunas have enabled the identification of Lower Miocene to Oligocene (N6 to P19) and Lower Eocene to Lower Palaeocene intervals (P6 to Pic). The remainder of the succession has been dated on benthonic evidence and spot age‐determinations on isolated planktonic occurrences. The palaeoenvironmental history of the Cainozoic sequence appears to be regressive from a bathyal situation in the Palaeocene through indeterminate marine Eocene, bathyal to inner shelf Oligocene to Middle Miocene, to reefal conditions which have persisted from the Middle Miocene to the present day.  相似文献   

7.
This paper presents the focal-mechanism solution of the Kinnaur (Himachal Pradesh) earthquake of January 19, 1975. Use was made of the first motions of P-waves and polarization (or first motions) of S-waves. The mechanism solution is characterized by a predominant component of normal faulting.  相似文献   

8.
长82亚油层组是甘肃庆城地区庄19井区上三叠统延长组中储集砂岩相对富集的层位,但砂岩低渗透性的特点显著,成为影响该区石油储产量增长的主要地质因素。结合前人的相关工作,通过钻井岩心观察、测井曲线分析、储层岩石实验测试等工作,详细地分析了庄19井区长82亚油层组低渗透储层的地质特征,认为沉积微相和压实作用、胶结作用是控制低渗透性储集砂岩发育和分布的主要地质因素,寻找以水下分流河道微相为代表的有利储集相带砂岩体是油气勘探的重要方向。  相似文献   

9.
2014年5月15日~9月1日期间,已建成的贵广铁路甘棠江特大桥19号墩基础产生了50.6~52.2 mm的异常下沉,20号墩基础产生了12.4~16.3 mm的异常下沉。现场补充完成了机动钻探、原位测试及室内试验工作。分析认为在多年强降雨条件下,深覆盖型岩溶强烈发育区的岩溶水水位波动产生潜蚀引起的岩溶塌陷,是导致该桥19、20号墩(采用摩擦桩基础,桩长约20 m)产生异常沉降的主要原因。对19、20号桥墩基底采取端承桩基础补强后,经过近2年的沉降观测,没有再发生异常沉降。文章认为在类似深覆盖型岩溶强烈发育区实施桥梁工程时,原则上应采用置于完整基岩内的端承桩基础。   相似文献   

10.
《Geoarchaeology》2004,19(6):613-613
The original article to which this Erratum refers was published in Geoarchaeology 19(3), 2004, 185–218. Due to an oversight, authorship of the paper by Bassett, K.N., Gordon, H.W., Nobes, D.C., & Jacomb, C. (2004), “Gardening at the edge: Documenting the limits of tropical Polynesian kumara horticulture in southern New Zealand” (Geoarchaeology 19, No. 3, pp. 185–218), was assigned incorrectly. The correct authorship is Hamish W. Gordon, Kari N. Bassett, David C. Nobes, and Chris Jacomb. The authors apologize for this error.  相似文献   

11.
在塔里木盆地西部台地区奥陶系蓬莱坝组地层中,发育了厚层的白云岩与灰岩的互层段,其中塔中19井蓬莱坝组云灰互层段存在着相对固定的岩性旋回,每个旋回上段为泥晶灰岩,中段为粉晶云岩,下段为硅化砂屑灰岩。对旋回3段泥晶灰岩/粉晶云岩/硅化砂屑(球粒)灰岩进行了地球化学研究发现:1)微量元素组成上,相比于泥晶灰岩与砂屑灰岩,白云岩富集大多数种类的微量元素。一般来说,白云岩样品的稀土总量(6.17×10-6~18.62×10-6)都高于互层的灰岩样品(2.86×10-6~6.80×10-6),但在PAAS标准化图解上,两者的配分模式却很一致,指示了白云岩为灰岩云化的产物。2)白云岩化分为两个期次,分别形成了高钡云岩与低钡云岩。高钡云岩表现出了高S特征,指示了Ba以重晶石形式在白云岩中富存;同时高钡云岩其高Fe、Mn含量特征指示了高钡云岩云化卤水来自热液。3)高钡云岩与低钡云岩表现出了不同的碳、氧同位素特征,指示了两期白云岩化事件。高钡云岩δ13C值与灰岩相当,δ18O值较高(-6.0‰~-3.2‰),可能指示了交代流体来源于岩浆热液;低钡云岩δ13C值为-1.7‰~-1.5‰,高于泥晶灰岩,δ18O值变化为-9.7‰~-8.5‰,低于泥晶灰岩,推测交代流体为海水演化热液。4)灰岩87Sr/86Sr值变化很小,为0.708 983~0.709 039,粉晶云岩白云岩87Sr/86Sr值较高,并且变化范围较大,为0.708 914~0.709 409,可能由成岩作用演化造成。由于粉晶云岩沿低孔渗条件的泥晶灰岩下层分布,热液流体进入云化体系的方式只能为流体从底部通过裂缝向上运移,遇盖层封堵而沿盖层下层流动发生云化。我们将这种云化模式定义为“顶侵型埋藏云化模式”,该模式下形成的白云岩与其上泥晶灰岩构成了良好的储盖组合,具有广阔的勘探前景。  相似文献   

12.
Summary The severity of damage to Mexico City as a result of the 19 September 1985 Michoacan earthquake was unusual given the City's distance (350 km) from the zone of seismic energy release. To explain the damage many authors have suggested that unusual source or transmission path characteristics contributed to enhanced ground motion in Mexico City. The purpose of this paper is to present a summary of results obtained from data recorded during the earthquake related to possible anomalous transmission path characteristics.It is concluded that in every respect this earthquake conformed to the norms set by previous subduction zone earthquakes within the Middle American trench. It appears likely that conditions within the Valley of Mexico are adequate to explain the unusually severe ground shaking without invoking unusual source or transmission characteristics.  相似文献   

13.
The 19 October 2012 earthquake (M L = 5.1) occurred in the northern continental margin of Egypt within the Nile Cone at latitude 32.35° N and longitude 31.27° E. The quake was felt over a wide area in north Egypt and East Mediterranean countries, but no casualties have been reported. This area had experienced the large earthquake (Ms = 6.7) of 12 September 1955. The fault plane solution of the 19 October 2012 earthquake is here presented based on the digital seismograms recorded by the Egyptian National Seismological Network (ENSN) and other regional seismic stations. The analysis is carried out using the well-known techniques of first motion polarities of P-wave and the amplitude ratios of P-, SH-, and SV-waves with lower hemisphere projection. The fault plane solution based on the first P-wave onset demonstrates a left lateral strike-slip faulting mechanism, while the solution based on both P-wave polarities and amplitude ratios of P-, SH-, and SV-waves reveals a reverse fault with strike-slip component trending NW–SE to NE–SW, in conformity with the N–S compression along the Hellenic Arc convergence zone. Following the Brune’s model, the source dynamic parameters for the 19 October 2012 earthquake are estimated as corner frequency = 1.47 Hz, fault radius = 0.7 km, stress drop = 22.1 MPa, seismic moment = 2.80E + 16 Nm, and moment magnitude M w = 4.9. These parameters may provide important quantitative information for the seismic hazard assessment studies.  相似文献   

14.
针对具有歧义的多期三角洲叠加层序的体系域划分问题,从层序地层划分的基础是沉积环境变化的同步性出发,以直接反映环境变化的孢粉、藻类为基础,结合岩性、电性特征、地震反射特征,解决了类似渤海海域渤中凹陷BZ19-4区多期三角洲叠加东二层序的体系域划分问题,指明了正确划分的方法与依据,同时也阐明了体系域划分对油气勘探的重要意义。  相似文献   

15.
Marked, 19th‐century kiln bricks and rocks from Caledonia Springs (CS) have black glass coatings that can easily be mistaken for glass produced at the elusive CS glassworks (c. 1844–1846). The glass‐on‐brick material, however, is more aluminous (nearly 20% Al2O3) than virtually any analyzed historical glass, and the glass‐on‐rock is compositionally similar to the rock itself, which shows clear signs of having undergone extensive melting. Mineral thermometry (Cpx‐Ol, Pl‐melt) indicates that parts of the kiln‐achieved temperatures of approximately 1200–1300°C. The CS samples show that caution must be exercised when identifying seemingly obvious waste glass near defunct glassworks sites. © 2005 Wiley Periodicals, Inc.  相似文献   

16.
窑街F19断裂带地质构造特征与演化分析   总被引:3,自引:0,他引:3  
该文研究了F19断裂带的构造组成与变形、构造岩的显微构造及该断裂带所控制的超基性岩等方面的特征,结果表明F19断裂带是一条在前中生代古断裂基础上经改造而发育起来的、影响地壳深度较大并曾控制煤田形成与演化而多期活动的复合性断裂;摩棱岩的发现与研究,表明基底岩系中曾发育韧性剪切带,其后本区发生过大幅度的抬升;侏罗纪时该断裂带控制含煤盆地的形成与演化而表现为典型的同生正断层;往后,该断裂主要以压剪性活动  相似文献   

17.
Elemental concentration data on up to 84 individual constituents in BHVO-1, MAG-1, QLO-1, RGM-1, SCo-1, SDC-1, SGR-1 and STM-1 have been collected from 311 journal articles and technical reports. These data are summarized in consensus (mean) values with uncertainties expressed as one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables.
Ce rapport rassemble des données analytiques parues dans 311 articles scientifiques ou rapports techniques sur 84 éléments dans huit échantillons du Service Géologique des Etats-Unis: BHVO-1, MAG-1, QLO-1, RGM-1, SCo-1, SDC-1, SGR-1 et STM-1. Quand cela a été possible, les valeurs de consensus (moyenne) sont présentées pour chaque élément avec l'incertitude exprimée en un écart-type. Des valeurs moyennes en fonction des procédures analytiques sont également présentées.  相似文献   

18.
The outbreak of COVID-19 raised numerous questions on the interactions between the occurrence of new infections, the environment, climate and health. The European Union requested the H2020 HERA project which aims at setting priorities in research on environment, climate and health, to identify relevant research needs regarding Covid-19. The emergence and spread of SARS-CoV-2 appears to be related to urbanization, habitat destruction, live animal trade, intensive livestock farming and global travel. The contribution of climate and air pollution requires additional studies. Importantly, the severity of COVID-19 depends on the interactions between the viral infection, ageing and chronic diseases such as metabolic, respiratory and cardiovascular diseases and obesity which are themselves influenced by environmental stressors. The mechanisms of these interactions deserve additional scrutiny. Both the pandemic and the social response to the disease have elicited an array of behavioural and societal changes that may remain long after the pandemic and that may have long term health effects including on mental health. Recovery plans are currently being discussed or implemented and the environmental and health impacts of those plans are not clearly foreseen. Clearly, COVID-19 will have a long-lasting impact on the environmental health field and will open new research perspectives and policy needs.  相似文献   

19.
The outbreak of COVID-19 raised numerous questions on the interactions between the occurrence of new infections, the environment, climate and health. The European Union requested the H2020 HERA project which aims at setting priorities in research on environment, climate and health, to identify relevant research needs regarding Covid-19. The emergence and spread of SARS-CoV-2 appears to be related to urbanization, habitat destruction, live animal trade, intensive livestock farming and global travel. The contribution of climate and air pollution requires additional studies. Importantly, the severity of COVID-19 depends on the interactions between the viral infection, ageing and chronic diseases such as metabolic, respiratory and cardiovascular diseases and obesity which are themselves influenced by environmental stressors. The mechanisms of these interactions deserve additional scrutiny. Both the pandemic and the social response to the disease have elicited an array of behavioural and societal changes that may remain long after the pandemic and that may have long term health effects including on mental health. Recovery plans are currently being discussed or implemented and the environmental and health impacts of those plans are not clearly foreseen. Clearly, COVID-19 will have a long-lasting impact on the environmental health field and will open new research perspectives and policy needs.  相似文献   

20.
The outbreak of COVID-19 raised numerous questions on the interactions between the occurrence of new infections, the environment, climate and health. The European Union requested the H2020 HERA project which aims at setting priorities in research on environment, climate and health, to identify relevant research needs regarding Covid-19. The emergence and spread of SARS-CoV-2 appears to be related to urbanization, habitat destruction, live animal trade, intensive livestock farming and global travel. The contribution of climate and air pollution requires additional studies. Importantly, the severity of COVID-19 depends on the interactions between the viral infection, ageing and chronic diseases such as metabolic, respiratory and cardiovascular diseases and obesity which are themselves influenced by environmental stressors. The mechanisms of these interactions deserve additional scrutiny. Both the pandemic and the social response to the disease have elicited an array of behavioural and societal changes that may remain long after the pandemic and that may have long term health effects including on mental health. Recovery plans are currently being discussed or implemented and the environmental and health impacts of those plans are not clearly foreseen. Clearly, COVID-19 will have a long-lasting impact on the environmental health field and will open new research perspectives and policy needs.  相似文献   

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