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1.
Molecular and supermolecular structures of fossilized resins from the North Eurasia have been studied in detail by IR-spectroscopy,
atomic force microscopy (AFM), scanning (SEM), and high-resolution transmission electron (HRTEM) microscopy. The analysis
of the IR-spectroscopy data allowed to identify the types of the fossil resins (succinite, rumanite, retinite, etc.). In the
succinites and rumanite, the supermolecular structure was observed by AFM. Sizes of the supermolecular particles are 50–120 nm.
Some chain-like and cluster-like aggregates can be observed when globules contact with each other. Using SEM and HRTEM techniques,
it has been shown that mineral impurities are mainly located as scattered inclusions (from one nanometers up to several tens
micrometers in size) in an amorphous organic matrix of the resin. 相似文献
2.
A. B. Herman M. A. Akhmetiev T. M. Kodrul M. G. Moiseeva A. I. Iakovleva 《Stratigraphy and Geological Correlation》2009,17(1):79-97
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
3.
Beckerite, a minor component of the amber fossil resins of northern Europe, has previously been classified as being mineralogically distinct from common Baltic amber or succinite on the basis of physical properties such as density and chemical properties such as saponification number. We show that beckerite and succinite are spectroscopically identical, according to infrared and carbon-13 nuclear magnetic resonance methods. Following the suggestion of Schubert, we attribute the deviations of beckerite to the presence of low levels of contaminants, such as decomposed wood and insect excrement. 相似文献
4.
The application of modern techniques such as infra-red absorption, mass and emission spectrometry, thin-layer chromatography and neutron activation analysis have been critically tested as a means for the identification of the geological localities of amber and other fossil resins. Thin-layer chromatography and emission spectrometry do not appear to reveal significant results. However, infra-red and mass spectrometry allow the identification of succinite, which may be geologically located in the vast area between the Black Sea, Carpathian Mountains, South Baltic, Sweden, Denmark, and Great Britain. 相似文献
5.
研究分析了大兴安岭及其邻区石炭-二叠纪地层,着重介绍各地层单元的分布范围、岩性组合、生物化石特征,特别总结了早、中二叠世冷水型和暖水型生物组合在本区局部出现的混生现象.根据本区板块构造发育,结合生物组合特征,进行了生物古地理分区的划分.本区北部属于北方大区,准噶尔-兴安区,兴安亚区;南部属于特提斯大区,华北区,华北北缘亚区. 相似文献
6.
F. P. Mitrofanov T. B. Bayanova A. U. Korchagin N. Yu. Groshev K. N. Malitch D. V. Zhirov A. F. Mitrofanov 《Geology of Ore Deposits》2013,55(5):305-319
This paper compares the geological, geophysical, and isotopic geochemical data on the Paleoproterozoic East Scandinavian Pd-Pt province in the Baltic Shield and the Late Paleozoic Noril’sk Pd-Pt province in the Siberian Craton. Both provinces contain large magmatic PGE deposits: low-sulfide in the Baltic Shield and high-sulfide in the Siberian Craton. Multidisciplinary evidence shows that the East Scandinavian mafic large igneous province, which has a plume nature, is intracratonic and was not subjected to the crucial effect of subduction-related and other contamination processes, whereas the Noril’sk province is pericratonic with substantial crustal contamination of the intrusive processes. Low-sulfide Pd-Pt deposits dominate in the East Scandinavian province, while high-sulfide Ni-Cu-PGE deposits play the leading role in the Noril’sk province. The U-Pb, Sm-Nd, and Rb-Sr isotopic data indicate multistage and long-term (tens of millions of years) geological history of mafic large igneous provinces. The plume magmatism with specific geochemistry and metallogeny is probably related to lower mantle sources. 相似文献
7.
塔里木盆地侏罗纪孢粉植物地理区系 总被引：1，自引：0，他引：1
塔里木盆地南部地区侏罗纪的孢粉化石 ,可分为 5个孢粉组合 :1) Cyathidites- Classopollis组合 ;2 ) Disac-ciatrileti- Cyathidites- Classopollis- Quadraeculina组合 ;3) Disacciatrileti- Cyathidites- Classopollis- N eoraistrackia组合 ;4) Disacciatrileti- Cyathidites- Classopollis组合 ;5 ) Cyathidites- Classopollis- Disacciatrileti组合。这些组合与塔北地区的组合明显不同 ,与我国华南亚区侏罗纪孢粉组合基本一致 ,属于华南侏罗纪孢粉植物地理亚区的范畴 ,而塔北地区的组合与我国华北亚区侏罗纪孢粉组合大体一致 ,属于华北侏罗纪孢粉植物地理亚区的范畴。因此 ,塔里木盆地侏罗纪孢粉植物地理分区界线应划在盆地的近中间 ,从西北向东南延伸 相似文献
8.
Romanian amber (rumanite) has been considered to be a separate species of fossil resin for more than a century. While earlier
investigators held it to be very similar to succinite (Baltic amber), modern scholars have assigned it a distinctly different
botanical origin. We have found that almost all of the constituents of the ether-soluble fractions of 13 specimens of authentic
rumanite identified by gas chromatography–mass spectrometry have previously been reported in the soluble fraction of succinite,
including succinic acid and its monoterpene esters. Additionally and significantly, the soluble fraction of rumanite contains
a number defunctionalized compounds that do not preexist in succinite, but that are produced by pyrolysis of whole succinite
or of its insoluble polymeric fraction. Simultaneous methylation pyrolysis–gas chromatography–mass spectrometry of the polymeric
fraction of seven of the rumanite specimens yielded further copious amounts of dimethyl succinate, a number of diterpene resin
acid methyl esters, and additional defunctionalized compounds known to be pyrolysis products of succinite. The evidence shows
conclusively that the botanical origin of rumanite is not distinct from that of succinite. Rather, rumanite is a succinite
that has suffered partial thermal degradation in the course of the folding of the Oligocene Kliwa sandstone formation in which
it is most commonly found.
Received: 30 December 1999 / Accepted: 16 May 2000 相似文献
9.
10.
Clay Minerals in Sediments of the Arctic Seas 总被引：2，自引：0，他引：2
The distribution of clay minerals in recent sediments on the Arctic shelf off the Eurasian and North American continents is considered. Prominence is given to the East Siberian and Laptev seas. The illite belt established on the basis of the composition of clay minerals in seven Arctic seas stretches from the Beaufort Sea to the White Sea and reveals a mineralogical zonality. The belt can be devided into smectite and chlorite provinces. Factors governing the formation of the Arctic illite belt and features of the distribution of individual clay minerals are discussed. The identification of the illite belt in sediments on the Arctic shelf complements the system of planetary latitudinal zones of clay minerals formulated by previous researchers. 相似文献
11.
亚洲3个大火成岩省(峨眉山、西伯利亚、德干)对比研究 总被引：1，自引：0，他引：1
峨眉山(～260 Ma)、西伯利亚(～250 Ma)和德干(～66 Ma)大陆溢流玄武岩是世界上3个重要的大火成岩省.大火成岩省至少具有4个通常被用于识别古地幔柱的标志:(1)先于岩浆作用的地表隆升;(2)与大陆裂谷化和裂解事件相伴;(3)与生物灭绝事件联系密切;(4)地幔柱源玄武岩的化学特征.虽然这3个大火成岩省都是来源于原始地幔柱,但是它们的地球化学特征有本质上的差异,反映其地幔柱曾与不同的上地幔库相互作用.(1)峨眉山和西伯利亚大陆溢流玄武岩的母岩浆,在上升过程中经受了与地球化学上和古老克拉通岩石圈地幔相同的上地幔库(EM1型幔源)的相互作用;(2)而德干大火成岩省没有受到地壳(或岩石圈)混染的原生玄武岩则显示地幔柱和EM2之间的Sr-Nd同位素变化.这种差异有可能制约了3个大火成岩省的成矿潜力.峨眉山和西伯利亚大火成岩省含有世界级岩浆矿床,而德干大火成岩省则不含矿. 相似文献
12.
《International Geology Review》2012,54(3):238-249
East Siberia comprises three petroleum provinces—Lena-Tunguska, Lena-Vilyuy, and Yenisey-Anabar—that occupy the area of the Siberian craton. Petroleum has been generated and has accumulated in Precambrian rifts beneath the sedimentary basins and, more importantly, within the section of the basin itself. The platformal deposits of the basins extend beneath overthrusts on the east and south and are covered by sedimentary rocks of the West Siberian overthrusts on the east and south and are covered by sedimentary rocks of the West Siberian province on the west. Permafrost and gas hydrate deposits are present throughout most of East Siberia. In the Lena-Tunguska province, rifts that developed during Riphean time are filled by thick sedimentary rocks, in which petroleum deposits have formed. In Early Cambrian time a barrier reef extended across the East Siberian craton from southeast to northwest. A lagoon to the west of this reef was the site of thick rhythmic salt deposits, which are the main seal for petroleum in the province. The sedimentary section of the platform cover ranges in age from Late Proterozoic to Permian. More than 25 oil and gas fields have been discovered in the province, all in Riphean through Lower Cambrian rocks. The Lena-Vilyuy province includes the Vilyuy basin and the Cis-Verkhoyansk foredeep. During Middle Devonian time, a rift formed along the axis of what was to become the Vilyuy basin. This rift is filled by Upper Devonian and Lower Carboniferous basalt, elastics, carbonates, and evaporites. During this rift stage the region that was to become the Cis-Verkhoyansk foredeep was an open geosynclinal sea. The sedimentary cover consists of Permian, coal-bearing sedimentary rocks as well as elastics from the Lower Triassic, Lower Jurassic, Lower Cretaceous, and Upper Cretaceous, the latter only in the Vilyuy basin. In the Lena-Vilyuy petroleum province as many as nine gas and gas-condensate fields have been discovered. The Yenisey-Anabar province is largely an extension of the West Siberian petroleum province. Permian sedimentary rocks are present only in the east, where they consist of elastics and some salt. The Triassic, Jurassic, and Cretaceous each are represented by thick clastic deposits. Total thickness of the sedimentary cover is up to 15 km on the west and 8 km on the east. Twelve gas and gas-condensate fields have been discovered in the western part of the province. 相似文献
13.
The phanerozoic within-plate magmatism of Siberia is reviewed. The large igneous provinces (LIPs) consecutively arising in
the Siberian Craton are outlined: the Altai-Sayan LIP, which operated most actively 400–375 Ma ago, the Vilyui LIP, which
was formed from the Middle Devonian to the Early Carboniferous, included; the Barguzin-Vitim LIP (305–275 Ma); the Late Paleozoic
Rift System of Central Asia (318–250 Ma); the Siberian flood basalt (trap) province and the West Siberian rift system (250–247
Ma); and the East Mongolian-West Transbaikal LIP (230–195 Ma), as well as a number of Late-Mesozoic and Cenozoic rift zones
and autonomous volcanic fields formed over the last 160 Ma. The trace-element and isotopic characteristics of the igneous
rocks of the above provinces are reviewed; their mantle origin is substantiated and the prevalence of PREMA, EM2, and EM1
mantle magma sources are shown. The paleogeographic reconstructions based on paleomagnetic data assume that the Iceland hot
spot was situated beneath the Siberian flood basalts 250 Ma ago and that the mantle plumes retained a relatively stable position
irrespective of the movements of the lithospheric plates. At present, the Iceland hot spot occurs near the northern boundary
of the African large low shear velocity province (LLSVP). It is suggested that the within-plate Phanerozoic magmatism of Siberia
was related to the drift of the continent above the hot spots of the African LLSVP. 相似文献
14.
《地学前缘(英文版)》2015,6(5)
The "Arctic" region,where the North Pole occupies the center of the Arctic Ocean,has been affecting the environmental variation of the Earth from geological time to the present.However,the seismic activities in the area are not adequately monitored.Therefore,by conducting long term monitoring of seismic phenomenon as sustainable parameters,our understanding of both the tectonic evolution of the Earth and the dynamic interaction between the cryosphere and geosphere in surface layers of the Earth will increase.In this paper,the association of the seismicity and structure of the Arctic region,particularly focused on Eurasian continent and surrounding oceans,and its relationship with regional evolution during the Earth's history is studied.The target areas cover representative tectonic provinces in the Eurasian Arctic,such as the wide area of Siberia,Baikal Rift Zone.Far East Russia,Arctic Ocean together with Greenland and Northern Canada.Based on discussion including characteristics of seismicity,heterogeneous structure of the crust and upper mantle,tectonic history and recent dynamic features of the Earth's surface in the Arctic are summarized. 相似文献
15.
重新认识中国斑岩铜矿的成矿地质条件 总被引：40，自引：10，他引：40
根据中国大陆洋陆作用的关系和造山带的演化，重新划分了中国斑岩铜矿成矿域和成矿带，将其分为古亚洲、北部特提斯、南部特提斯(喜马拉雅)和环太平洋4个成矿域。古亚洲成矿域又分为华北陆块北缘早-中古生代成矿带、哈萨克斯坦地块东北缘晚古生代成矿带、哈萨克斯坦地块南缘中晚古生代成矿带、西伯利亚板块西南缘晚古生代成矿带。特提斯北部成矿域分为中咱地块西缘晚三叠世义敦成矿带、羌塘地块(昌都-思茅地块)北缘古近纪玉龙成矿带、塔里木地块南缘晚古生代-新生代成矿带、扬子地块西缘古近纪成矿带。南部特提斯(喜马拉雅)成矿域分为班公错成矿带和冈底斯成矿带。环太平洋成矿域分晚中生代活动陆缘成矿带和台湾古近纪-新近纪岛弧成矿带。综合分析中国大陆地质演化史与斑岩铜矿成矿地质背景，对中国斑岩铜矿勘查工作具有重要参考价值。 相似文献
16.
岩浆热液型银矿床主要指与岩浆热液作用相关的独立银矿床和共生银矿床(Ag平均品位一般大于100g/t),它是银最重要的来源。本文对全球80多个典型的大型-超大型岩浆热液型银矿床进行了梳理和总结,将其主要分为浅成低温热液型(低硫型、中硫型和高硫型)、矽卡岩型、斑岩型和五元素型四种类型,其中浅成低温热液型占主导,斑岩型和矽卡型数量较少。全球大型-超大型的岩浆热液型银矿床主要分布在东太平洋俯冲带和中亚造山带东段,这些银矿床均位于陆壳基底之上。按照发育地区不同可分为六大银成矿省,即中国兴蒙银成矿省、美国西部盆岭银成矿省、墨西哥西北银成矿省、秘鲁中部银多金属成矿省、玻利维亚银锡成矿省和俄罗斯远东银锡成矿省。成矿时代主要集中在中、新生代。这些银成矿省与大规模酸性-中酸性岩浆活动密切相关,包括发育大量酸性熔结凝灰岩的长英质大火成岩省,或者富锡流纹岩、黄玉流纹岩和石英斑岩等高演化岩浆岩。这些大规模岩浆热液银成矿作用通常与区域大地构造背景转换相关,比如从挤压到伸展或者伸展到挤压。相对富银的含水大陆下地壳源区、大规模高分异的岩浆作用、银对熔体中共存硫化物和磁铁矿相对弱的相容性、高盐度的流体、成矿流体集中运移的通道和高效的沉淀机制是银大规模成矿的有利控制因素。银矿床的研究工作相对于铜、金矿床远远落后,银成矿省和酸性大火成岩省的内在联系、控制斑岩钼-银/锡-银两种银成矿系统的机制、岩浆演化对银成矿的控制、银矿潜力区的勘查找矿等关键问题仍亟待解决。 相似文献
17.
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
18.
Joseph B. Lambert Suzanne C. Johnson George O. Poinar James S. Frye 《Geoarchaeology》1993,8(2):141-155
The carbon-13 nuclear magnetic resonance spectra of fossil resins from New Zealand and Australia have been compared with those of modern and semifossilized materials. The great majority of the fossilized samples have strong spectral similarities to modern Agathis resins and to North American fossil resins, which have been attributed to Agathis. The Agathis-related spectra are different from those of modern Hymenaea and Araucaria. A small subgroup of Late Cretaceous resins from Australia and Papua New Guinea appears to derive from a different botanical source and shows strong resemblances to Claiborne amber from Arkansas. The spectral resonances of the exomethylene carbons degrade over time and on average provide an approximate measure of the geological age of Agathis-related fossil resins. © 1993 John Wiley & Sons, Inc. 相似文献
19.
中国及邻区石炭纪构造古地理及生物古地理 总被引：1，自引：0，他引：1
本文包括3部分:（1）扼要回顾了中国及邻区晚海西阶段的地质构造背景和构造古地理特征。根据全球构造活动论和地壳发展阶段论的观点,把中国及邻区晚海西阶段的大地构造单元分为4个构造域,10个亚构造域。（2）论述中国和世界石炭纪生物古地理分区。根据四射珊瑚和腕足动物群分析,把全球早石炭世生物古地理区系分为两个生物大区、6个生物区和8个生物亚区。在中国境内对生物亚区内部生物地方中心的分异作了进一步划分。（3）简述中国石炭纪古地理和某些有关的沉积矿产。中国石炭系矿产除了重要的煤以外,还有石膏矿、铝土矿和不同类型的铁矿。这些沉积矿产的分布主要受到古气候、古地理和构造条件的控制。 相似文献
20.
中国大陆地壳和岩石圈化学成分模型可信吗? ——来自大地热流值的检验 总被引：3，自引：0，他引：3
大地热流值是大陆地壳和岩石圈U，Th,K丰度的直接约束；根据地球化学元素丰度值推算出的大地构造单元的区域地壳热流值，必定不能大于区域的平均热流值，根据700余个实测大地热流数据，对目前发表的中国大陆地壳和岩石圈的化学成分模型进行了检验，结果表明，多数模型不能满足大地热充约束，如黎彤等的关于中国大陆及其内部构造单元的地壳和岩石圈成分模型，倪守斌等提出的新疆北部地壳生热率模型，以及高山等提出的扬子地台北缘地壳成分模型，这些模型的U，Th,K丰度值不太可靠，其他强不相容元素的丰度值的可信程度亦值得怀疑，而迟清华，鄢明才提出的华北地台地壳成分模型和高山等建立的中国东部及华北地台和秦岭造山带的地壳成分模型通过了区域大地热流的检验。 相似文献