首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
H.  D.卡尔克 《第四纪研究》1986,7(2):129-133
在晚第三纪晚期和第四纪时, 欧亚大陆古动物群的面貌受两个陆桥的影响很大, 在尽西边有一个复合陆桥, 即非洲与欧洲相连, 与亚洲沿着非洲西边—伊比利亚半岛连接;中间的非洲—西西里岛陆桥和一个东地中海陆桥(非洲—阿拉伯半岛)连接。  相似文献   

2.
In August 2013, anoxia of the bottom waters was established in the southern region of the Far East Marine Biosphere Reserve, Far East Branch, Russian Academy of Science, in the depression between Furugelm Island and coastal waters. Death of the benthic community was registered using a remotely operated underwater vehicle. The hydrochemical studies revealed that the area of the absence and/or presence of low oxygen contents corresponds to an area of anomalously high contents of ammonium, phosphates, and silicates, a high partial pressure of carbon dioxide and normalized alkalinity, and the presence of hydrogen sulfide. The microbiological decomposition of diatoms precipitated on the seafloor in the absence of oxygen regeneration was the reason for anoxia. Its formation in summer of 2013 was caused by anomalously abundant precipitates in the Far East.  相似文献   

3.
The investigation is focused on identification and origin of fossil resins from the Cretaceous, Tertiary, and Quaternary sediments of Northern Eurasia on the basis of detailed study of their physical and chemical characteristics: morphology; size; mass; density; optical, mechanical, and thermal properties; chemical composition; etc. The composition of amorphous organic minerals with polymeric structure, fossil resins included, is studied with IR spectrometry, the EPR method, derivatography at low heating rates, XRD, chemical analysis, emission spectrometry, etc. The results of investigation summarized for the Baltic-Dnieper, North Siberian, and Far East amber-bearing provinces show some similarity of fossil resins in combination with specific features inherent to each province. Resins from the Baltic-Dnieper province should be termed as amber (succinite). Their variety is the most characteristic of Northern and Eastern Europe. Amber-like fossil resins from the North Siberian and Far East provinces are irrelevant to succinite. They usually occur as brittle resins, namely, retinite and gedanite, without jewelry value. Viscous fossil resin rumänite with an expected high economic value occurs in the Far East, on the shore of Sakhalin Island.  相似文献   

4.
俄罗斯东部地区油气资源远景分析   总被引：1，自引：0，他引：1  
俄罗斯东部地区油气资源十分丰富,而且远景储量巨大。其石油储量远景区主要圈定在东西伯利亚地区晚元古代-早古生代陆源碎屑岩-碳酸盐岩含油气盆地,远东地区中-新生代大陆架硅质岩含油气盆地和远东滨海坳陷中古新世-始新世杂砂岩含油气建造等。而且,远东地区含油气盆地的形成时代自西向东逐渐变年轻,具体由侏罗纪、白垩纪过渡为新生代。俄罗斯东部地区中-新生代煤层气盆地广布,其中最主要的煤层气盆地为勒拿河流域盆地和南雅库特盆地。煤层气的成因及分布特征主要受控于盆地的基本地质特征,即上覆、下伏地层层系和褶皱断裂构造、变质作用等。俄罗斯远东地区萨哈林大陆架、鄂霍茨克海以及白令海阿列乌特深水海盆中蕴藏大量的天然气水合物资源。天然气水合物中的甲烷一般被认为来自深部油气层,但也有专家认为它可能来自大陆架以外的深海海域。  相似文献   

5.
俄罗斯地质学家在近20年来以岩石圈板块构造理论和地体分析方法,对中-东西伯利亚和俄罗斯远东地区构造和区域成矿作用的研究取得了一系列重要进展。这些进展集中体现在2个多国合作项目取得的成果和2部最新的科学专著中。作者重点介绍了中-东西伯利亚和俄罗斯远东地区区域构造演化、区域构造和区域成矿单元及一些重要金属矿床的基本特征,并对本区地质演化的某些重要问题（转换陆缘、蒙古-鄂霍茨克造山带等）做了讨论,以此向读者提供一个有关俄罗斯东部地区上述领域基本研究现状的梗概。  相似文献   

6.
In certain areas, relatively large accumulations of liquid hydrocarbons have been attributed to coals. Evaluating the source rock potential of coal requires definition of both the generative potential (quantity and composition of generated hydrocarbons), and expulsion efficiency. Hydrous pyrolysis experiments were completed using Tertiary lignites (Ro < 0.35%) from North Dakota and the Far East to evaluate the source rock potential of coal. The North Dakota lignite is vitrinite-rich (93%) and liptinite-poor (3%); the Far East lignite is liptinite-rich (32% of total maceral content). These lignites have Hydrogen Index values of 123 and 483 mg HC/g OC, respectively. Differences in oil-pyrolysate yield, composition, and temperature of maximum pyrolysate yield from hydrous pyrolysis experiments for these two lignites are related to the type and amount of liptinite and vitrinite macerals. A maximum of 48 and 158 mg oil-pyrolysate/g OC is generated and expelled from the North Dakota and Far East lignites, respectively. Although these lignites consist predominantly of gas-prone vitrinitic components, their organic-rich nature can compensate for their poor convertibility to liquid hydrocarbons. The composition of these artificially generated oil-pyrolysates are similar to some non-marine oils, suggesting that this type of organic matter can be a significant contributor to many oils. Although the overall composition of the generated products from the two lignites is similar, the distribution of these products is significantly different. Homologous series of methyl ketones and alkyl benzenes have been identified in both oil-pyrolysates. Their presence and characteristic distribution suggest that microbial degradation occurred during the formation of these lignites. Although many coals generate significate amounts of liquid hydrocarbons that are similar to naturally occurring oils, poor explusion efficiency limits their source rock potential. Significant amounts of liquid products are assimilated by the vitrinitic matrix of most coals prior to expulsion, severely limiting the amount of petroleum available for migration and reservoir accumulation. However, adequate expulsion may occur in certain liptinite-rich coals or coals occurring in unique depositional settings.  相似文献   

7.
Plume-related oceanic magmatism form oceanic islands, seamounts and plateaus (hereafter “seamounts” or “paleoseamounts”), which are important features in geological history. The accretion of oceanic seamounts to active continental margins significantly contributed to the formation of the continental crust. This paper reviews occurrences of Late Neoproterozoic–Mesozoic seamounts of the Paleo-Asian and Paleo-Pacific oceans, which are hosted by accretionary complexes (ACs) of Russian Altai, East Kazakhstan, Mongolia, Russian Far East and Japan. The paleoseamounts commonly consist of Ti–LREE–Nb-enriched plume-related basalts (OIB-type or intraplate basalts) capped with massive limestone and associated with other units of oceanic plate stratigraphy (OPS): oceanic floor basalts (MORB), pelagic chert, epiclastic slope facies, etc. The paper presents available geochemical data on the plume-related basalts including the first geochemical data on the Middle Paleozoic OIB-type basalts of the Paleo-Asian Ocean hosted by the Ulaanbaatar AC of Mongolia. An emphasis is made for the structural setting of OPS units, specific geochemical features of intraplate basalts, problems of their identification, and distinguishing from magmatic units of a different origin such as MORB, island-arc and back-arc basalts. Finally, we propose a continuous, though periodical, evolution of the Pacific superplume-related magmatism, which can be more reliably proved by studying Middle Paleozoic OPS units hosted by ACs of Mongolia and Tien Shan, and discuss prospects of future studies.  相似文献   

8.
Study of floral succession from the Cretaceous-Paleogene boundary interval in Russian Far East (Zeya-Bureya depression), Northeastern Russia (Koryak Upland), and Northern Alaska (Sagavanirktok River basin) is crucial for better understanding palaeoclimatic and palaeogeographic factors, which controlled events in vegetation evolution at that time. The succession of fossil floras in the Zeya-Bureya depression includes plant assemblages of the Santonian, Campanian, early Danian, Danian, and Danian-Selandian age. The early Danian Boguchan Flora keeps continuity in composition and dominating taxa with the Campanian Late Kundur Flora. The Koryak Flora of the Amaam Lagoon area (Northeastern Russia) is dated as late Maastrichtian based on correlation of plant-bearing beds with marine biostratigraphy, whereas the Early and Late Sagwon floras of Northern Alaska are dated back to the Danian-Selandian and early Paleocene based on palynological and macrofloristic data. The Early Sagwon Flora is most close to the late Maastrichtian Koryak Flora of the Amaam Lagoon area in composition and main dominants, while the Late Sagwon Flora is comparable with the Danian or Danian-(?) Selandian flora from the Upper Tsagayan Subformation of the Amur area. In a florogenic aspect, trans-Beringian plant migrations from northeastern Asia and southern palaeolatitudes of the Far East, which became possible due to Paleocene climate warming in Arctic, have played an important role in forming of the Paleocene floras of Northern Alaska. Floras of the Far East and high latitudes of Asia and North America show no evidence of catastrophic event at the Cretaceous-Paleogene boundary. Their development was most probably controlled by climate changes, plant evolution and migration.  相似文献   

9.
The resource base for the Russian tin industry is surveyed district by district, with emphasis on deposit geology and mineralogy, world and domestic market conditions, production linkages between mines and processing facilities, and exploration activity. Current Russian output is less than one-half the former Soviet total of the mid-1980s, a reflection of difficult economic conditions, divergent interests of mine producers and the management of the Novosibirsk tin smelter, and declining ore tenor at certain major deposits. Major deposits now are found exclusively in Russia's Far East economic region, often in remote and climatically inhospitable locations. Unlike most other major producing countries, the bulk of Russia's output comes from lode deposits rather than placers. A concluding section outlines factors expected to affect future tin demand in Russia and describes efforts to identify potentially promising nontraditional tin ore deposits.  相似文献   

10.
张春晖 《地质与资源》2007,16(1):47-49,55
近年来,俄罗斯远东地区铂族金属矿床勘查取得了长足进展,发现铂族金属矿化与金矿化密切相关,铂族金属矿床与中心型环带状基性-超基性侵入杂岩体在空间和成因上有密切联系,在黑色岩系及褐煤矿床中也发现了铂族金属矿化.上述成果指明了该区铂族金属矿床的找矿方向,发现并探明了一批铂族金属矿床.这些勘查进展对我国的铂族金属矿床勘查具有借鉴意义.  相似文献   

11.
Correlation of the Permian continental and marine deposits of Northeastern Russia, the southern Far East, Siberia, and the Pechora Сisurals is carried out. A consistent zonal succession of brachiopods, marine bivalves, and ammonoids is revealed and linked with the macroflora in the boundary deposits of the Cisuralian/Biarmian Series of the Boreal Superrealm. As a result, analogues of the Solikamian, Irenskii, Filippovskii, and Saraninian Horizons of the Kungurian Stage are established in the main coal basins and marine sequences of Northeastern Russia and the southern Far East. The correlative floristic horizon, stretching from the east of the East European Platform to the Pechora Cisurals, Pai-Khoy, Siberia, the Kuznetsk Basin, Northeastern Russia, and the southern Far East is established. The unity of the Sheshmian–Kazanian nonmarine floral assemblages and nonmarine bivalves, which correspond to the marine biota of Kazanian age, and their distinction from Kungurian assemblages are established. The Kungurian–Kazanian boundary is traced in marine and continental deposits within the entire Boreal Superrealm. The invalidity of the Ufimian Stage is established. The Kazanian Stage corresponds to the Roadian Stage of the International Chronostratigraphic Chart; however, the lower boundary of the Kazanian Stage is not defined precisely and can be conventionally considered isochronous to the boundary of the Roadian Stage.  相似文献   

12.
The Pacific coast, including the Kamchatka Peninsula, the Kuriles, the Sea of Japan, the Sea of Okhotsk, and the Bering Sea, is the main tsunami-prone area in Russia. The Far East tsunamis are much more frequent, extensive, and devastating than those in the Black, Caspian, Baltic, and White Sea coasts, as well as in major inland lakes of Baikal, Ladoga, etc. The tsunami catalog of the Russian Far East from 1737 to present lists 110 events with mainly near-field and few far-field sources (105 and 5 events, respectively). Most of the catalogued tsunamis (95 cases) were induced by earthquakes, and few events had volcanic (3), landsliding (2), meteorological (3), and unknown (2) triggers. Altogether there were eleven devastating tsunamis for the period of observations, with > 10 m heights, two of which were great events in 1737 and 1952, when the waves exceeded 20 m. The wave heights were in the range 2.5-10 m in fifteen hazardous tsunami events and within the tidal range (~ 1-2 m) in thirteen cases; the other events were small and detectable only instrumentally. Thus, the average recurrence times for tsunamis of different magnitudes in the Russian Pacific coast are 25 years for devastating events and 10-15 years for hazardous tsunamis; small tsunamis occur almost every year, according to statistics for the last sixty years collected at the regional network of tide stations. The topics discussed in the paper concern the completeness and reliability of the Far East catalog; distribution of tsunami events in space and time; correlation between the intensity of tsunami and the magnitude of the causative undersea earthquake; tsunami recurrence; tsunami warning; and long-term hazard assessment and mapping.  相似文献   

13.
Accessory mineralization of the Late Cretaceous intrusive series in the Far East was investigated on the basis of published data and the author’s original evidence. The composition of accessory minerals from leucogranite, monzonitoid rocks, and Li–F granites has been established. The trend in the evolution of Late Cretaceous granitoids is characterized by an increase in the mineral-forming role of iron and rare elements. Diverse accessory minerals and their typomorphic assemblages have been identified for Li–F granites and ongonites. The regional specificity of accessory mineralization in rare-metal granites consists in the leading role of the minerals W, Ta, Nb, Bi, Y, REE, and As. The uniformity of mineral species and mineral assemblages and the typomorphism and evolution of accessory minerals are inherent to the Far East belt of Li–F granites.  相似文献   

14.
This study presents new data on major, trace and REE element concentration of groundwaters in Lastochka spa located in the northern part of Primorye, Far East of Russia. The studied area is characterized by two types of groundwaters issued from a spring and wells: fresh waters with low mineralization (Total Dissolved Solids is up to 400 mg/l) and high pCO2 waters with high mineralization (TDS is up to 4700 mg/l). New data and previous δ13C(TIC), oxygen (δ18O) and hydrogen (δ2H) isotope data indicate that these waters result from meteoric water infiltration in the Sikhote–Alin mountain, circulating at shallow depths in sedimentary rocks. CO2 in groundwater is of mantle origin.  相似文献   

15.
Doklady Earth Sciences - This paper reports the results of the third Russian–Vietnamese expedition (V.I. Il'ichev Pacific Oceanological Institute, Far East Branch, Russian Academy of...  相似文献   

16.
《International Geology Review》2012,54(10):1216-1224
  相似文献   

17.
The remote First Nation (FN) communities of the Mushkegowuk Territory on the west coast of James Bay, Ontario, Canada are currently facing increased development pressures and the imposition of a government land use planning process. The land use planning process is mandated in the Far North Act (received Royal Assent on September 23, 2010). There is a need for capacity enhancement for community-based natural resource planning and management in the Territory. A number of frameworks are emerging for addressing change brought on by resource development and building resilience to such change at the community level. Among these include the concept of adaptive capacity. In collaboration with FN community leaders, we explored the use of “collaborative geomatics” tools to foster adaptive capacity. Our action research suggests that collaborative geomatics technologies should enhance the Mushkegowuk First Nations’ adaptive capacity to address environmental and policy change by allowing them to collect and manage data collaboratively (e.g., traditional environmental knowledge, western science) to create opportunities for innovative community development, including natural resource development and management.  相似文献   

18.
东海海域油气资源与选区评价   总被引：5，自引：1，他引：4  
为优化勘探目标的选择,加快东海海域的油气勘探与开发步伐,在油气勘探开发现状和资源潜力分析的基础上,采用油气地质综合研究的方法进行了东海海域的油气勘探战略选区评价。东海油气资源丰富,勘探前景广阔,但不同区域勘探潜力不一,以东海陆架盆地最为重要,冲绳海槽盆地次之。东海陆架盆地的油气勘探以西湖凹陷最具潜力,瓯江凹陷和闽江凹陷次之,其中西湖凹陷的油气勘探以始新统和渐新统为重点层系,瓯江凹陷以古新统为主攻目标,闽江凹陷以中生界为主要勘探层位。冲绳海槽盆地具备油气藏形成的基本地质条件,以陆架前缘坳陷最为有利,以中新统为重点勘探层位。  相似文献   

19.
The research history of allanite-(Y) has been considered. The composition and genesis of this mineral is discussed with allowance for new findings in Li-F granites of the Russian Far East. Compositional anomalies in allanite-(Y) reflect the metastable character of its structure. Types of zoning and trends in the chemical substitution of major components are described. Two crystal chemical modes of allanite-(Y) formation and the two-step isomorphism of its components are suggested. The main tendencies in the chemical evolution of allanite-(Ce) and allanite-(Y) in granitic rocks of the Far East are pointed out. Allanite-(Y) is formed in the anomalous geochemical setting that characterizes crystallization of fluid-saturated subalkaline granitic melt and is regarded as an index mineral of rare-metal ongonite magmatism completing the Late Cretaceous Pacific Orogeny.  相似文献   

20.
《International Geology Review》2012,54(10):1135-1143
The physical basis of paleomagnetism is described. The methods of rock paleomagnetic correlation are considered; the method of remanent magnetization direction, the method of inversions and the method of remanent magnetization amount. The possibilities and fields of application of each method are considered. The results of Far East basalt age correlations carried out by author are given.—Auth.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号