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1.
Chen Xi WANG Chengshan HU Xiumian HUANG Yongjian WANG Pingkang Luba JANSA ZENG Xuan 《《地质学报》英文版》2007,81(6):1070-1086
Cretaceous oceanic red beds (CORBs) represented by red shales and marls, were deposited during the Cretaceous and early Paleocene, predominantly in the Tethyan realm, in lower slope and abyssal basin environments. Detailed studies of CORBs are rare; therefore, we compiled CORBs data from deep sea ocean drilling cores and outcrops of Cretaceous rocks subaerially exposed in southern Europe, northwestern Germany, Asia and New Zealand. In the Tethyan realm, CORBs mainly consist of reddish or pink shales, limestones and marlstones. By contrast, marlstones and chalks are rare in deep-ocean drilling cores. Upper Cretaceous marine sediments in cores from the Atlantic Ocean are predominantly various shades of brown, reddish brown, yellowish brown and pale brown in color. A few red, pink, yellow and orange Cretaceous sediments are also present. The commonest age of CORBs is early Campanian to Maastrichtian, with the onset mostly of oxic deposition often after Oceanic Anoxic Events (OAEs), during the early Aptian, late Albian-early Turonian and Campanian. This suggests an indicated and previously not recognized relationship between OAEs, black shales deposition and CORBs. CORBs even though globally distributed, are most common in the North Atlantic and Tethyan realms, in low to mid latitudes of the northern hemisphere; in the South Atlantic and Indian Ocean in the mid to high latitudes of the southern hemisphere; and are less frequent in the central Pacific Ocean. Their widespread occurrence during the late Cretaceous might have been the result of establishing a connection for deep oceanic current circulation between the Pacific and the evolving connection between South and North Atlantic and changes in oceanic basins ventilation. 相似文献
2.
3.
The Cretaceous sedimentary rocks of the Pindos Zone in western Greece document the evolution of a Tethyan deep-water basin. New sedimentological and micropalaeontological studies reveal a complex basin history. Siliceous sediments with abundant radiolaria and organic-rich facies prevailed up to the early Late Cretaceous. Within the sediment-starved pre-Middle Cenomanian, marked black shale levels appear that are probably linked to oceanic anoxic events. At the change from the late Early to the early Middle Cenomanian, the sedimentary regime altered abruptly. The early Late Cretaceous is characterized by major calcareous redepositional events (orbitoline horizons) and often associated siliciclastic turbidite deposition (submarine-fan environments). In the late Late Cretaceous, carbonate supply increased rapidly, resulting in the evolution of a carbonate slope and basin-plain setting. Pelagic and allodapic limestones recorded basinwide blooms in planktonic foraminifera (elevata event) and a polyphase redepositional history that is interpreted to reflect the sensitivity of the basin to the tectonic evolution of Apulia. 相似文献
4.
Zhenguo ZHANG Nianqiao FANG Lianfeng GAO Baoling GUI Muhua CUI 《Frontiers of Earth Science》2008,2(1):41-48
The Cretaceous is an important period in which many geological events occurred, especially the OAEs (oceanic anoxic events)
which are characterized by black shale, and the oxic process characterized by CORBs (Cretaceous oceanic red beds). In this
paper, the causative mechanism behind the formation of black shale and the oceanic red beds are described in detail. This
may explain how the oceanic environment changed from anoxic to oxic in the Cretaceous period. It is suggested that these two
different events happened because of the same cause. On the one hand, the large-scale magma activities in Cretaceous caused
the concentration of CO2, the release of the inner energy of the earth, superficial change in the ocean-land, and finally, the increase of atmospheric
temperature. These changes implied the same tendency as the oceanic water temperature show, and caused the decrease in O2 concentration in the Cretaceous ocean, and finally resulted in the occurrence of the OAEs. On the other hand, violent and
frequent volcanic eruptions in the Cretaceous produced plenty of Fe-enriched lava on the seafloor. When the seawater reacted
with the lava, the element Fe became dissolved in seawater. Iron, which could help phytoplankton grow rapidly, is a micronutrient
essential to the synthesis of enzymes required for photosynthesis in the oceanic environment. Phytoplankton, which grows in
much of the oceans around the world, can consume carbon dioxide in the air and the ocean. Meanwhile, an equal quantity of
oxygen can be produced by the phytoplankton during its growth. Finally, the oxic environment characterized by red sediment
rich in Fe3+ appeared. The anoxic and oxic conditions in the Cretaceous ocean were caused by volcanic activities, but they stemmed from
different causative mechanisms. The former was based on physical and chemical processes, while the latter involved more complicated
bio-oceanic-geochemical processes.
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Translated from Marine Geology & Quaternary Geology, 2007, 27(3): 69–75 [译自: 海洋地质与第四纪地质] 相似文献
5.
鲁西隆起区发育有大量的北西向脆性断裂。依据野外断裂构造的几何学、运动学详细解析认为,北西向断裂系经历了早期的右行压剪、右行张剪,以及后期的左行压剪等不同性质的构造活动。由与北西向断裂活动相伴生的同期侵入岩体的 K-Ar测试结果分析,北西向断裂系在距今约160 Ma及距今130~110 Ma分别经历了右行压剪与右行张剪构造活动;通过分布在隆起区不同样品的磷灰石裂变径迹数据分析、冷却史反演,厘定鲁西地体在距今90~80 Ma存在一次区域性快速冷却构造事件,该构造事件与北西向断裂系的左行压剪构造活动相对应。 相似文献
6.
Abstract Regional metamorphism in central Inner Mongolia has occurred during four different periods: the middle Proterozoic, the early Palaeozoic, the middle Palaeozoic and the late Palaeozoic tectonic cycles. The middle Proterozoic and late Palaeozoic metamorphic events are associated with rifting and are characterized by low-pressure facies series. The early Palaeozoic metamorphism occurred in two stages: (1) subduction zone metamorphism resulted in paired metamorphic belts in the Ondor Sum ophiolite and Bainaimiao island arc complex; and (2) orogenic metamorphism occurred during the collision of an island arc with the continent. Two types of middle Palaeozoic metamorphism are represented: (1) subduction zone metamorphism, which affected the melange; and (2) orogenic metamorphism that resulted from continent–continent collision. 相似文献
7.
鲁西北西向断裂系晚中生代活动的几何学、运动学及年代学研究 总被引：3，自引：0，他引：3
鲁西隆起区发育有大量的北西向脆性断裂.依据野外断裂构造的几何学、运动学详细解析,认为北西向断裂系经历了早期的右行压剪、右行张剪,以及后期的左行压剪等不同性质的构造活动.由与北西向断裂活动相伴生的同期侵入岩体的 K-Ar测试结果分析,北西向断裂系在距今约160 Ma及距今130～110 Ma分别经历了右行压剪与右行张剪构造活动;通过分布在隆起区不同样品的磷灰石裂变径迹数据分析、冷却史反演,厘定鲁西地体在距今90～80 Ma存在一次区域性快速冷却构造事件,该构造事件与北西向断裂系的左行压剪构造活动相对应. 相似文献
8.
The Coniacian-Santonian interval has been proposed as the youngest of the Cretaceous ocean anoxic events (OAE3), but this designation has long been debated. OAE3 is associated with a long-lasting (∼3 myr) succession of black shales from the central and South Atlantic, Caribbean region, and the North American Western Interior; in the Western Interior it is characterized by an abrupt increase in total organic carbon (TOC) and corresponding trace metal indicators for anoxia. However, the modern concept of OAEs is predicated on detection of global carbon cycle perturbations as recorded by substantial carbon isotope excursions (CIE), and the protracted Coniacian-Santonian black shale interval does not have a large CIE. A more conservative definition of OAE3 might limit the event to the modest positive carbon isotope excursion restricted to the upper Coniacian Scaphites depressus Ammonite Zone. Trace metal proxies suggest that oxygen levels abruptly declined prior to the onset of this CIE in the Western Interior Sea (WIS), but it is unknown whether regional anoxic conditions were confined to sediments/pore waters, or how anoxia may have affected the biota. In an effort to characterize the oxygenation history of the WIS and to better understand the nature of the hypothesized OAE3, we present micropaleontological evidence of declining oxygen in bottom waters prior to the event using benthic foraminifera, which are sensitive to dissolved oxygen. Changes in benthic foraminiferal abundances suggest a decline in oxygen at least 1-myr prior to the CIE (including a nadir immediately below the start of the excursion), improving bottom water oxygen during the CIE, and re-establishment of persistent anoxia following the isotope excursion. Anoxia endured for nearly 3 myr in the central seaway, showing some signs of recovery toward the top of the Niobrara Formation. Our findings suggest that declining oxygen concentrations in the seaway eventually reached a tipping point, after which dissolved oxygen quickly dropped to zero.The late Coniacian CIE is an exception to the trend of declining oxygen in the WIS, and part of a larger pattern in the oxygenation history of the Niobrara Formation which suggests that it does not adhere to standard black shale models. Transgressive periods, including the Fort Hays Limestone and the lower limestone unit of the Smoky Hill Shale (which corresponds to the CIE) are relatively oxic, while periods of highstand (i.e., most of the Smoky Hill) correspond to deteriorating oxygen conditions. This contrasts with the standard black shale model for sea level and oxygen, where transgressions typically correlate with maximum TOC enrichment, interpreted to result from both sediment condensation and oxygen deficiency. The association of global carbon burial/anoxia (as indicated by carbon isotopes) with a regional increase in oxygen and decrease in organic matter preservation is reminiscent of the Cenomanian-Turonian Greenhorn Limestone, which contains OAE2. In both cases, the facies are not typical black shales, but instead have appreciable carbonate content. Western Interior redox trends support the rejection of the original concept of a protracted Coniacian-Santonian OAE3 because it is not a distinct “event.” Increasing local oxygen during the late Coniacian CIE also argues against a narrower OAE designation for this event, because the excursion can't be tied to anoxia here or anywhere else it has been described. Nevertheless, the Late Coniacian Event (as we prefer to call this CIE) still represents an important perturbation of the global carbon cycle. This is emblematic of the shift away from widespread, discrete anoxic events during the ongoing paleoceanographic reorganization of the Late Cretaceous, even as large carbon cycle perturbations continued. 相似文献
9.
《International Geology Review》2012,54(15):1884-1905
Considerable attention has been given to the Carnian (Late Triassic) Pluvial and Reingraben events associated with organic-rich shale accumulation in the Germanic basin, Alps, southern Appenines as well as in northwestern Tethyan margins. Less interest has been shown to the southern Tethyan portion represented by the northern margin of Africa, including Tunisia. Tunisian basins represented by the Tellian domain, Tunisian trough, the ‘Dorsale’, and the North–South Axis (NOSA) belong to the southern Tethyan margin, where northern and central areas record the early Carnian anoxic event within an extensive carbonate platform. This short-lived (~2 million year) period of anoxia ranges within the Aonoides to Austriacum ammonite zones, and corresponds in Tunisia generally to intermediate to shallow water environments marked by organic-rich black limestone, dolomite, and shale. Interestingly, toward the south, the dysaerobic conditions in the Jeffara–southern Dahar basin appear to have prevailed locally also in the early Carnian. Here we review evidence of early Carnian anoxia in Tunisia based on the analysis of more than 17 Triassic sections and wireline logs from several petroleum exploration wells penetrating the black dolomites, limestones, and shales. In addition, biostratigraphic and complete geochemical reviews have been undertaken from published papers and unpublished internal reports to better assess this important and promising hydrocarbon source interval. 相似文献
10.
《International Geology Review》2012,54(4):461-480
ABSTRACTThe Ordos Basin has experienced a complicated tectonic evolution since the Palaeozoic. Its multi-stage evolution was closely related to the tectonic events that occurred along plate boundaries. The detrital zircon ages and crystallization age (CA)-deposition age (DA)/cumulative proportion curves obtained from Palaeozoic-Mesozoic strata from different tectonic units in and around the western Ordos Basin demonstrate that during the early Palaeozoic, the so-called Helan Aulacogen did not develop along the western Ordos Basin, the Alxa Block was an independent unit from the North China Craton, and the southern Ordos Basin was a foreland basin of the North Qinling Orogenic Belt. During the early Palaeozoic, the western Ordos Basin and its vicinity belonged to three different tectonic units (i.e. the North China Craton, the Alxa Block, and the North Qilian Orogenic Belt). At the end of the early Palaeozoic, the Alxa Block amalgamated with the Ordos Basin. From the Silurian to the Middle Devonian, the southern Alxa Block was a foreland basin of the North Qilian Orogenic Belt and underwent regional extension during the Late Devonian. During the late Palaeozoic, the western Ordos Basin and its vicinities were located in a back-arc extensional setting of the western Qinling Orogenic Belt. The southern part of the western Ordos Basin may have been a retro-arc foreland basin of the western Qinling Orogenic Belt during the Late Triassic, and the northern part of the western Ordos Basin experienced large-scale left-lateral strike-slip at the same time. The CA-DA/cumulative proportion curves can adequately explain the evolution of the western Ordos Basin during the Palaeozoic; however, the settings indicated by the CA-DA/cumulative proportion curves in intraplate evolutions are different from those proposed in other studies, which may be due to the number and distribution of samples and rapid lateral changes in sedimentary facies. 相似文献
11.
Rock relationships in the Mogok metamorphic belt, Tatkon to Mandalay, central Myanmar 总被引：5，自引：0，他引：5
A.H.G. Mitchell Myint Thein Htay Kyaw Min Htun Myint Naing Win Thura Oo Tin Hlaing 《Journal of Asian Earth Sciences》2007,29(5-6):891-910
The Mogok metamorphic belt (MMB), over 1450 km long and up to 40 km wide, consists of regionally metamorphosed rocks including kyanite and sillimanite schists and granites lying along the Western margin of the Shan Plateau in central Myanmar and continuing northwards to the eastern Himalayan syntaxis. Exposures in quarries allow correlation of Palaeozoic meta-sedimentary, early Mesozoic meta-igneous and late Mesozoic intrusive rocks within a 230 km long northerly-trending segment of the MMB, from Tatkon to Kyanigan north of Mandalay, and with the Mogok gemstone district 100 km to the northeast. Relationships among the metamorphic and intrusive rocks, with sparse published radiometric age controls, indicate at least two metamorphic events, one before and one after the intrusion of Late Jurassic to early Cretaceous calc-alkaline rocks. These relationships can be explained by either of two possible tectonic histories. One, constrained by correlation of mid-Permian limestones across Myanmar, requires early Permian and early Jurassic regional metamorphic events, prior to an early Tertiary metamorphism, in the western part of but within a Shan-Thai – western Myanmar block. The second, not compatible with a single laterally continuous Permian limestone, requires pre-Upper Jurassic regional metamorphism and orogenic gold mineralization in the Mergui Group and western Myanmar, early Cretaceous collision of an east-facing Mergui-western Myanmar island arc with the Shan Plateau, and early Tertiary metamorphism in the MMB related to reversal in tectonic polarity following the arc-Plateau collision. 相似文献
12.
Roberto Graziano 《地学学报》2001,13(2):110-116
Huge megabreccias occur at the eastern margin of the Cretaceous Apulia Carbonate Platform (Gargano Promontory, southern Italy). Their stratigraphic and genetic meaning are controversial in the debated geological evolution of the Apulia Platform. New stratigraphic analyses have revealed that three distinct megabreccia levels occur within the coarse debrites that were previously interpreted to be the result of repeated collapses of a scalloped platform margin during the late Albian–Cenomanian. Each level has peculiar chronostratigraphic distribution, geometry, composition and genetic features. They are the Posta Manganaro Megabreccias (late early Aptian to late Albian pp. ), Monte S. Angelo Megabreccias (early–middle Cenomanian) and Belvedere di Ruggiano Megabreccias (middle Turonian). These deposits overlie regional, tectonically enhanced unconformities of late early Aptian, late Albian and late Cenomanian age. These megabreccias, which were formed, respectively, during drowning, prograding and exposure events of the Apulia Platform, reflect important turning points in its Cretaceous geodynamic evolution. 相似文献
13.
大火成岩省对全球性大气-海洋环境的巨变及生物灭绝有非常重要的影响。已有研究结果表明,显生宙（即寒武纪以来）大火成岩省与全球大洋缺氧与生物灭绝有明显的成因联系,显生宙国际地质年代表中多个金钉子均与以大火成岩省、黑色页岩及生物灭绝为代表的全球性地质事件相对应。但由于对前寒武纪,特别是"地球中年期"（18~8亿年,"枯燥的10亿年"）大气氧浓度、海洋的氧化-还原状态及生物门类及演化认识的局限性,关于前寒武纪大火成岩省与环境的影响及其与黑色页岩沉积的成因联系一直很不清楚。通过对全球哥伦比亚（奴那）超大陆中约13.8亿年全球性大火成岩省及黑色页岩沉积时空分布的研究,发现这些大火成岩省及黑色页岩的分布有明显的规律。约13.8亿年大火成岩省广泛分布在北美、格陵兰、西伯利亚、波罗地、卡拉哈里、刚果、西非、亚马逊、南极及西澳大利亚等大陆上;而同期的黑色页岩在华北及北澳大利亚克拉通广泛分布,在西伯利亚、巴西及印度等克拉通也有分布。根据这些黑色页岩在超大陆重建图中的空间分布,提出了哥伦比亚（奴那）超大陆中这些广泛分布的约13.8亿年黑色页岩可能沉积于连通的大型海相盆地,而不是以往所认为的局部封闭的小盆地。通过约13.8亿年大火成岩省与黑色页岩内火山灰（斑脱岩）年龄的对比,进一步提出约13.8亿年存在一次与全球性大火成岩省有关的大洋缺氧事件,以此期大火成岩省与黑色页岩为代表的全球性地质事件为中元古代盖层系与延展系提供了精确的界限年龄为1383 Ma。初步的研究结果还显示,"地球中年期"可能还有多期的大火成岩省与黑色页岩沉积有时空联系,有望为晚前寒武纪地质年代表划分提供新的事件约束。 相似文献
14.
Vassilis Karakitsios Harilaos Tsikos Yvonne van Breugel Lyda Koletti Jaap S. Sinninghe Damsté Hugh C. Jenkyns 《International Journal of Earth Sciences》2007,96(2):343-352
Integrated biostratigraphic (planktonic foraminifera, calcareous nannofossils), chemostratigraphic (bulk C and O isotopes)
and compound-specific organic geochemical studies of a mid-Cretaceous pelagic carbonate—black shale succession of the Ionian
Zone (western Greece), provide the first evidence for the Cenomanian–Turonian oceanic anoxic event (OAE2, ‘Bonarelli’ event)
in mainland Greece. The event is manifested by the occurrence of a relatively thin (35 cm), yet exceptionally organic carbon-rich
(44.5 wt% TOC), carbonate-free black shale, near the Cenomanian–Turonian boundary within the Vigla limestone formation (Berriasian–Turonian).
Compared to the ‘Bonarelli’ black-shale interval from the type locality of OAE2 in Marche–Umbria, Italy, this black shale
exhibits greatly reduced stratigraphic thickness, coupled with a considerable relative enrichment in TOC. Isotopically, enriched
δ13C values for both bulk organic matter (−22.2‰) and specific organic compounds are up to 5‰ higher than those of underlying
organic-rich strata of the Aptian-lower Albian Vigla Shale member, and thus compare very well with similar values of Cenomanian–Turonian
black shale occurrences elsewhere. The relative predominance of bacterial hopanoids in the saturated, apolar lipid fraction
of the OAE2 black shale of the Ionian Zone supports recent findings suggesting the abundance of N2-fixing cyanobacteria in Cretaceous oceans during the Cenomanian–Turonian and early Aptian oceanic anoxic events. 相似文献
15.
白垩纪诸多地质事件中,以黑色页岩为特征的大洋缺氧事件和以红层为特征的大洋富氧环境尤其引人关注。本文探讨了白垩纪大洋从缺氧到富氧转化的过程与机制,认为上述沉积事件是地球圈层之间相互作用的结果。白垩纪岩石圈剧烈的岩浆活动,是缺氧、富氧事件发生的源动力,水圈、大气圈、生物圈的共同作用是沉积事件发生的结果。具体过程为:白垩纪大规模的火山喷发,改变了海陆面积的对比,并引起地球内部大量热能释放和大气中CO_2气体浓度的升高,最终导致大气温度的升高。海水温度的升高和CO_2浓度的增加导致海洋环境中溶解O_2的降低,缺氧事件随之而产生。同时,海底岩浆喷发在海底产生大量的富含铁元素的基性和超基性岩石,通过海底风化和热液活动,铁元素从岩石圈进入水圈。海水中的铁元素是海洋浮游植物宝贵的营养盐类,其含量的增加可激发浮游植物的大规模繁盛,而这一生命过程可以吸收海水中大量的CO_2,并且产生等量的O_2。随着海水中O_2浓度的不断升高,以富含Fe3+的红色沉积物为特征的海洋富氧环境出现。藏南和深海钻探、大洋钻探典型剖面的数据证实大洋缺氧和富氧发生的韵律性,即缺氧事件之后往往伴随富氧环境的出现。研究认为,白垩纪大洋缺氧和富氧事件是同一原因导致的不同结果,地球圈层相互作用是其根本制约因素。由岩浆活动引起的缺氧事件和同样由其造成的富氧环境,其机制存在明显的差异,前者以物理、化学过程为主,后者除此之外还演绎了更为复杂的生物-海洋地球化学过程。 相似文献
16.
17.
Benthic foraminiferal assemblages of late Aptian-early Albian black shale intervals in the Vocontian Basin, SE France 总被引：1，自引：0，他引：1
Benthic foraminiferal assemblages were analyzed from three black shale intervals in the upper Aptain to lower Albian of the Vocontian Basin, SE France based on Q-mode principal component analyses. Variations in the distribution patterns of benthic foraminifera around these events suggest differences in the origin of the black shales. Differences between faunas of bioturbated marly and laminated black shale facies have been observed in the Niveau Paquier, Oceanic Anoxic Event (OAE) 1b and Niveau Leenhardt. Here, the faunal composition and plankton/benthos ratios suggest eutrophic conditions during the deposition of organic-rich sediments leading to black shales. No major variations have been observed in black shales of the upper Aptain Niveau Jacob. Benthic assemblages and low plankton/benthos ratios indicate mesotrophic conditions. Third order sea-level changes are believed to control mainly the origin of the investigated black shale levels. 相似文献
18.
内蒙古东北部额尔古纳地区上护林-向阳盆地中生代
火山岩LA-ICP-MS锆石U-Pb年龄和地球化学特征 总被引：9，自引：5，他引：4
LA-ICP-MS锆石U-Pb测年结果表明,研究区中生代火山岩可分为2期,分别是早白垩世早期(约144Ma)吉祥峰组流纹岩类和早白垩世晚期(约125Ma)上库力组流纹岩类与梅勒图组玄武岩类。早白垩世早期吉祥峰组流纹岩富硅、富碱、富钾(K2O/Na2O>1),富集轻稀土元素和Rb、Th、U等元素,亏损重稀土元素、高场强元素(Nb、Ta、Ti)及Sr、P,具有A型流纹岩的特征,暗示其形成于伸展环境。早白垩世晚期火山岩显示双峰式岩石组合特征,基性端元富碱、高钾,富含轻稀土元素和Rb、Ba,亏损重稀土元素和高场强元素(Nb、Ta、Ti、Y),类似于钾玄质玄武岩,酸性端元显示A型流纹岩的特征。双峰式火山岩组合的存在暗示其形成于陆内拉张的构造环境。结合区域上中生代火山岩的空间分布规律,认为早白垩世早期火山岩的形成与蒙古-鄂霍次克缝合带的演化有关,早白垩世晚期双峰式火山岩的形成与古太平洋板块向欧亚大陆下的俯冲作用相联系。 相似文献
19.
湘中湘南地区在早古生代时期,由于受海平面变化以及全球古气候的影响,形成了有利于烃源岩形成的沉积环境。笔者通过对湘中湘南地区的奥陶纪达瑞威尔中晚期-凯迪早期开展沉积相、岩相古地理和油气地质等研究,结合前人所取得的相关研究成果,将该区划分为陆架相、盆地相和陆架边缘相。陆架相主要由砂质板岩、砂岩、黑色页岩和硅质岩组成;陆架边缘相为粉砂-细粒石英砂岩、长石石英砂岩夹条带状板岩、炭质板岩和硅质岩等组成;而盆地相为一套炭质页岩和硅质岩组成的黑色岩系,代表了一种平静还原的滞流缺氧环境。该套岩性有机质含量高,具较高的生烃潜力,且分布范围广,是湘中湘南地区达瑞威尔-凯迪阶的富烃沉积区,也是下一步油气地质调查和勘探的重要层位。 相似文献
20.
东北地区油气领域接替形势展望
（代序） 总被引：2，自引：0，他引：2
东北地区存在5套油气勘探层系.松辽盆地内的白垩系松花江群坳陷层系是目前生产的主力,已进入稳产阶段后期.下白垩统的断陷层系仅在松辽、二连、海拉尔等盆地发现油气田,正处于勘探开发高潮期.以断陷为主体的下—中侏罗统含煤层系是待探索的新领域,可能在白垩系(甚至上侏罗统火山岩)覆盖下保存.近年来,东北地区上古生界的含油气远景已被广泛认可,并开展了选区评价工作.东北东部的新生界断陷含有丰富的煤、油页岩,其下可能有白垩系深埋,但受浅部火山岩的影响,对其深部的研究工作不足.针对以上5个领域的特点提出了今后的研究方向,特别强调了新领域开拓以及常规和非常规油气勘探并举. 相似文献