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1.
Within the context of the southwestern Barents Sea, the southern Stappen High and its transition to the Bjørnøya Basin are still underexplored. Improved quality seismic reflection data are utilised to describe new insights into the Paleozoic to early Cenozoic tectono-stratigraphic evolution of the area, as well as to discuss the structural inheritance and the rift development. Well-defined syn-rift wedges and better resolution images for both the deep Carboniferous and Permian successions are revealed. In particular, both the mid-Carboniferous and Late Permian-earliest Triassic extensional phases are characterized by widespread NE-SW oriented normal faults that are mostly westward dipping. Although Triassic is mostly considered as a tectonically stable period in the Barents Sea, in the southern Stappen High there is clear identification of a localised depocentre (named herein “Intra Stappen Basin”) where syn-tectonic geometries characterize the upper Paleozoic and Triassic deposits. Regional correlation to Middle and Upper Triassic outcrops in southwestern Svalbard reveals possible progradation from a west-northwest Northeast Greenland provenance as a western sediment source area during the Triassic, in addition to the well-known eastern sediment source area. Thin but distinct Jurassic sequences are expected to be present on Stappen High associated with prominent regional NW-SE extension throughout Late Jurassic that culminated during the earliest Cretaceous. Furthermore, structural and stratigraphic relations are observed within the study area that clearly indicate a distinct early Aptian rift phase with increasing evidence for its occurrence in the southwestern Barents Sea. Upper Cretaceous sequences bounded by major low-angle west-dipping detachment faults are observed in southwest Stappen High. During early Cenozoic, the study area was located at the proximity of the paleo-coastline and paleo-shelf edge for both Paleocene and Eocene gravity mass-waste deposits. These are most probably related to a progressively evolving steep bathymetric gradient between the developing margin, mainly towards the west and to the south, and the uplifted Stappen High. 相似文献
2.
The Triassic through to the Middle Jurassic (Bathonian) stratigraphy of the Kerr McGee 97/12-1 exploration well is described using petrophysical logs, in association with lithological and palaeontological analyses. Over 6210′ of sediment was penetrated, with sixteen Triassic and fourteen Lower–Middle Jurassic sedimentary units recognised, with a total measured depth (T.D) of 7310′ within the Sherwood Sandstone Group, Budleigh Salterton Pebble Beds of Early/Middle Triassic, Olenekian/Anisian age. As expected the sedimentary sequences are comparable to those described from the Wessex Basin, especially the Portland–Wight and Dorset (sub) basins. Of particular note, however, is the very thick halite sequence (1074′) within the Carnian, Dunscombe Mudstone Formation and also an expanded “Paper Shales” (27′) sequence within the earliest Toarcian. A normal fault is noted at 1260′ with the Late Bajocian, Inferior Oolite Group in fault contact with the latest Toarcian, Bridport Sand Formation, Down Cliff Clay Member. The Late Triassic (Rhaetian) to Middle Jurassic (Bathonian) yielded rich microfaunal and palynomorph assemblages, all of which have been previously described throughout northwest Europe. Four microfossils groups (foraminifera, ostracods, dinocysts and miospores) have been used to interpret stratigraphic ages and palaeoenvironments.This study provides new lithological and microfossil data for the Triassic to Middle Jurassic (Bathonian) sequences preserved in the offshore Portland–Wight Basin and provides a key tie-point/reference section for future offshore drilling. 相似文献
3.
南黄海盆地是在前震旦系克拉通基础上发育的中、古生界海相与中、新生界陆相多旋回叠合盆地。通过地震资料解释,结合邻区钻井与区域地质资料,对南黄海盆地中部隆起中、古生代地层及其形成演化进行了研究,结果表明,南黄海盆地中部隆起沉积了较全的中、古生界海相地层,发育第四系—新近系、中—下三叠统青龙组、上二叠统、下二叠统—上泥盆统、中—下志留统,奥陶系—震旦系和前震旦系变质岩系等7套地震地质层序;主要经历了前震旦纪基底形成、震旦纪—早古生代克拉通发育、晚古生代—中三叠世稳定台地—陆内裂陷、晚三叠世—古近纪形成与抬升剥蚀及新近纪-第四纪坳陷沉降5个阶段。 相似文献
4.
C. Hübscher M.B. Hansen S.P. Triñanes H. Lykke-Andersen D. Gajewski 《Marine and Petroleum Geology》2010,27(4):923-938
The post-Permian sequence stratigraphical and structural evolution of the Northeastern German Basin and its transition onto the Baltic Shield has been studied in the Bay of Mecklenburg (SW Baltic Sea) by means of seismic interpretation. Five major sequences have been identified: Middle Triassic, Upper Triassic, Jurassic, Cretaceous and Cenozoic. Time–isochore maps allowed the identification of several phases of salt pillow growth. The contemporaneity of active salt tectonics and the well studied tectonic evolution of the Northeastern German Basin suggest a causative correlation. The E–W directed extension during the Triassic-Early Jurassic marking the beginning break-up of Pangaea is seen as the trigger process for the first period of salt movement. A fault system outside the limit of the Zechstein evaporates is understood as the consequence of thin-skinned faulting and brittle thick-skinned deformation that accompanied this extension. The observed pronounced erosion of Upper Triassic and Lower Jurassic strata is considered to result from the uplift due to the Mid North Sea Doming event in Middle Jurassic times. The seismic data show an undisturbed Late Cretaceous succession which reflects a period of rising sea level, tectonic quiescence and no salt movement. In contrast to the salt pillows which emerged above Triassic fault systems in the westernmost Baltic and western North German Basin, the Cenozoic salt movement activity is the most pronounced. This period of reactivated salt pillow growth started coevally with the onset of the Alpine orogeny at the Cretaceous/Cenozoic transition when the Africa-Arabian plate collided with Eurasia. Generally, no significant faults were identified in the overburden of the salt floored southern Bay of Mecklenburg where ductile Zechstein salt decouples deep rooted faulting from supra-salt deformation. 相似文献
5.
A stable isotopic study, focused on calcite cements, vein-fill calcite and various bioclasts was conducted on variably deformed and thrusted Lower and Middle Permian carbonates of the Saraburi Group. Samples were collected in quarry faces across 3 areas in the Saraburi–Lopburi region of central Thailand. Stable isotope crossplots (carbon and oxygen), using texture-aware isotope samples, defined variable, but related, fluid-cement histories, which are tied to regional burial and then orogenic overprints driven by the Indosinian (Triassic) orogeny. This was followed by telogenetic overprints, driven by late Cenozoic uplift. The studied carbonates were deposited along the western margin of the Indochina Block, where they were deposited as isolated calcareous algal, sponge and fusilinid-rimmed platforms on highs bound by extensional faults. The platform areas passed laterally and vertically into more siliciclastic dominated sequences, deposited in somewhat deeper waters within probable fault-bound lows. Regional post-depositional mesogenetic fluid-rock re-equilibration of the isotope values in ongoing calcite precipitates occurred until the matrix permeability was occluded via compaction and pressure solution. This regional burial regime was followed by collision of the Indochina and Sibumasu blocks during the Indosinian (Triassic) blocks, which drove a set of structurally focused (thrust-plane related) increasingly warmer set of fluids through the studied sequences. The final diagenetic overprint seen in the isotopic values of the latest calcite cements occurs in a telogenetic (uplift) setting driven by Cenozoic tectonics and isostatic uplift. Integration of isotope data with its structural setting establishes a clear separation in fluid events related to two time-separate tectonic episodes; its fluid chemistry defines the Permo-Triassic closure of the Paleotethys and its subsequent reactivation during the Tertiary collision of India and Asia. The C–O covariant plot fields in the Permian carbonates of central Thailand are so distinct that it is possible to use their signatures to separate burial from meteoric cements in drill cuttings and hence recognise equivalent subsurface unconformities and likely zone of porosity development in possible “buried hill plays in Thailand. 相似文献
6.
S. Yu. Sokolov E. A. Moroz A. S. Abramova Yu. A. Zarayskaya K. O. Dobrolubova 《Oceanology》2017,57(4):593-599
On cruises 25 (2007) and 28 (2011) of the R/V Akademik Nikolai Strakhov in the northern part of the Barents Sea, the Geological Institute, Russian Academy of Sciences, conducted comprehensive research on the bottom relief and upper part of the sedimentary cover profile under the auspices of the International Polar Year program. One of the instrument components was the SeaBat 8111 shallow-water multibeam echo sounder, which can map the acoustic field similarly to a side scan sonar, which records the response both from the bottom and from the water column. In the operations area, intense sound scattering objects produced by the discharge of deep fluid flows are detected in the water column. The sound scattering objects and pockmarks in the bottom relief are related to anomalies in hydrocarbon gas concentrations in bottom sediments. The sound scattering objects are localized over Triassic sequences outcropping from the bottom. The most intense degassing processes manifest themselves near the contact of the Triassic sequences and Jurassic clay deposits, as well as over deep depressions in a field of Bouguer anomalies related to the basement of the Jurassic–Cretaceous rift system 相似文献
7.
8.
Multiphase rifts tend to produce fault populations that evolve by the formation of new faults and reactivation of earlier faults. The resulting fault patterns tend to be complex and difficult to decipher. In this work we use seismic reflection data to examine the evolution of a normal fault network in the Oseberg Fault Block in the northern North Sea Rift System – a rift system that experienced Permian – Early Triassic and Middle Jurassic – Early Cretaceous rifting and exhibits N-S, NW-SE and NE-SW oriented faults.Both N-S- and NW-SE-striking faults were established during the Permian – Early Triassic rifting, as indicated by Triassic growth packages in their hanging walls. In contrast, the NE-SW-striking faults are younger, as they show no evidence of Permian – Early Triassic growth, and offset several N-S- and NW-SE-striking faults. Structural analysis show that a new population of NW-SE-striking faults formed in the Lower – Middle Jurassic (inter-rift period) together with reactivation of N-S-striking Permian – Early Triassic faults, indicating a NE-SW inter-rift extension direction.During the Middle Jurassic – Early Cretaceous rifting, faults of all orientations (N-S, NW-SE and NE-SW) were active. However, faults initiated during the Middle Jurassic – Early Cretaceous rifting show mainly N-S orientation, indicating E-W extension during this phase. These observations suggest a reorientation of the stress field from E-W during the Permian – Early Triassic rift phase to NE-SW during inter-rift fault growth and back to E-W during the Middle Jurassic – Early Cretaceous rift phase in the Oseberg area. Hence, the current study demonstrates that rift activity between established rift phases can locally develop faults with new orientations that add to the geometric and kinematic complexity of the final fault population. 相似文献
9.
Jurassic–Cretaceous siliceous–volcanogenic rocks from nappes of tectonostratigraphic sequences of the East Asia Middle Cretaceous Okhotsk–Koryak orogenic belt are represented by a wide range of geodynamic sedimentation settings: oceanic (near-spreading zones, seamounts, and deep-water basins), marginal seas, and island arcs. The taxonomic compositions of radiolarian communities are used as paleolatitude indicators in the Northern Pacific. In addition, a tendency toward climate change in the Mesozoic is revealed based on these communities: from the warm Triassic to the cold Jurassic with intense warming from the Late Jurassic to the Early Cretaceous. Cretaceous warming led to heating of ocean waters even at moderately high latitudes and to the development of Tethyan radiolarians there. These data are confirmed by a global Cretaceous temperature peak coinciding with a high-activity pulse of the planetary mantle superplume system, which created thermal anomalies and the greenhouse effect. In addition, the Pacific superplume attributed to this system caused accelerated movement of oceanic plates, which resulted in a compression setting on the periphery of the Pacific and the formation of the Okhotsk–Koryak orogenic belt on its northwestern framing in the Middle Cretaceous, where Mesozoic rocks of different geodynamic and latitudinal–climate settings were juxtaposed into allochthonous units. 相似文献
10.
为了对普光气田主体碳酸岩沉积体系和各种微相特征深入研究,建立区域地层格架,对普光气田主体井层序界面进行识别与划分。研究表明：主要发育有升隆侵蚀层序不整合面、海侵上超层序不整合面、水下沉积间断层序不整合面、局部暴露层序不整合界面和岩性岩相转换界面等五种三级层序界面,同时发育岩性的突变面、沉积相转换面、GR值正向漂移和成岩作用变化等四种四级层序界面。普光102-1井下三叠统飞仙关组可划分为一个二级层序、两个三级层序和九个四级层序,并对其中可作为有利储层的层序进行分析。 相似文献
11.
印支运动以后,在现今的南海及其周围存在过2个古海洋,其中晚侏罗世一早白垩世消失于南海北部陆缘区、北巴拉望-礼乐滩-南沙地块以北的古海洋为“中特提斯”,而早第三纪期间消失于南沙地块以南沙捞越一带的古海洋为“古南海”。它们的结束时间和消失的古地理位置完全不同。对它们的正确识别和区分,对目前进行的南海周边地区中一新生代构造演化研究极为重要。对马来半岛、加里曼丹岛中生代岩相古地理资料的整理和分析结果支持如下结论：中特提斯洋的延伸是从苏门答腊的Woyla缝合线,过婆罗洲的Meratus缝合线。然后绕西南婆罗洲地块至加里曼丹岛的西北(Lupar带或者Boyan带),进入南海西南角(南沙-礼乐滩-北巴拉望地块等以北),再接南海北部陆缘区内的中特提斯缝合线。该区中生代海相地层的分布明显受构造演化的控制,整体趋势是向南退缩。印支运动以前、早-中三叠世的海侵广泛分布于古特提斯带及以南地区,涉及华南,中南地块,马来半岛及以南地区;印支运动基本结束了古特提斯带的海侵,因此晚三叠世一早侏罗世的海侵主要限于中特提斯海域及以南地区,如与中特提斯洋相邻的陆域,包括华南的湘赣粤海湾晚三叠世一早侏罗世的海侵、中南半岛东南部早侏罗世的海侵以及新加坡早侏罗世的海相地层。白垩纪海相地层主要分布于中特提斯以南地区,如加里曼丹岛。 相似文献
12.
The Middle to Upper Triassic series in the Norwegian Barents Sea represents an important target for hydrocarbon exploration. However, the dating and correlation of these rocks are problematic due to the scarcity of age-diagnostic macrofossils, lateral facies variation and the overall thickness of the succession. Palynology has proven to be a useful dating tool but further work is necessary to improve the zonal resolution, particularly for the Upper Triassic Series. The current paper presents a detailed palynostratigraphy of the Middle – Upper Triassic succession in four exploration wells (7120/12-2, 7228/2-1s, 7-1a and 9-1s) drilled in the Hammerfest and Nordkapp basins. Eleven informal palynological zones are described from the stratigraphic interval spanning the Kobbe, Snadd and Fruholmen formations, which constitute regionally significant hydrocarbon source and reservoir rock facies. The results of this study contribute to a higher resolution palynostratigraphy for the Middle to Upper Triassic strata of the southern Barents Sea (SBS), and an improved correlation with the stratigraphy of the Svalbard Archipelago. Palynofacies data for the succession, presented here for the first time, indicates depositional environments ranging from fluvio-deltaic to offshore marine. 相似文献
13.
The “red beds” of the Triassic succession outcropping at Tejra-Medenine (southern Tunisia, Saharan Platform) have yielded rich fossil assemblages of both freshwater and brackish-marine invertebrates and vertebrates. The new discovered fauna indicates an Anisian-Lower Ladinian age for the Tejra section. Its lowermost part is considered as equivalent of Ouled Chebbi Formation, while the medium and upper parts are considered as equivalent of the Kirchaou Formation. Both sedimentological characteristics and fossil assemblages indicate the increasing marine influences within the middle part of the section and the migration of brackish and freshwater fauna into the lacustrine/playa environment at the top. The marine fauna-rich interval of the Tejra section correlates well with the well-known Myophoria-rich carbonate stratigraphic marker confirming the Middle Triassic (Ladinian) major transgression well recorded eastward in the Tunisian Jeffara basin and in Libya. The use of this Ladinian stratigraphic event in addition to the Carnian carbonate transgressive events of the Jeffara escarpment outcrops was of great help for regional lithostratigraphic correlations between the Triassic outcropping series and those currently buried in Ghadames and Berkine basins. The age of the sandstones of “Trias Argilo-Gréseux Inférieur” (TAGI) which forms the main oil and gas reservoir in the Saharan domain is attributed to the Anisian-Carnian and considered as coeval of Ouled Chebbi and Kirchaou Formations of the Dahar escarpment. An updated synthetic stratigraphic chart is proposed for the Triassic of Saharan Platform domain on the basis of the compilation of the new obtained results and the subsurface data taken from published literature. 相似文献
14.
The deep lacustrine gravity-flow deposits are widely developed in the lower Triassic Yanchang Formation, southeast Ordos Basin, central China. Three lithofacies include massive fine-grained sandstone, banded sandstone, and massive oil shale and mudstone. The massive fine-grained sandstones have sharp upper contacts, mud clasts, boxed-shaped Gamma Ray (GR) log, but no grading and Bouma sequences. In contrast, the banded sandstones display different bedding characteristics, gradational upper contacts, and fine-upward. The massive, fine-grained sandstones recognized in this study are sandy debrites deposited by sandy debris flows, while the banded sandstones are turbidites deposited by turbidity currents not bottom currents. The sediment source for these deep gravity-flow sediments is a sand-rich delta system prograding at the basin margin. Fabric of the debrites in the sandy debris fields indicates initial formation from slope failure caused by the tectonic movement. As the sandy debris flows became diluted by water and clay, they became turbidity currents. The deep lacustrine depositional model is different from the traditional marine fan or turbidite fan models. There are no channels or wide lobate sand bodies. In the lower Triassic Yanchang Formation, layers within the sandy debrites have higher porosity (8–14%) and permeability (0.1–4 mD) than the turbidites with lower porosity (3–8%) and permeability (0.04–1 mD). Consequently, only the sandy debrites constitute potential petroleum reservoir intervals. Results of this study may serve as a model for hydrocarbon exploration and production for deep-lacustrine reservoirs from gravity-flow systems in similar lacustrine depositional environments. 相似文献
15.
Thick Triassic siliciclastic units form major reservoir targets for hydrocarbon exploration on the Barents Shelf; however, poor reservoir quality, possibly associated with variation in provenance, remains a key risk factor in the area. In this study, sandstone dispersal patterns on the southwest Barents Shelf are investigated through petrographic and heavy mineral analysis, garnet and rutile geochemistry and zircon U-Pb geochronology. The results show that until the Early Norian Maximum Flooding Surface, two contrasting sand types were present: (i) a Caledonian Sand Type, characterised by a high compositional maturity, a heavy mineral assemblage dominated by garnet and low chrome-spinel:zircon (CZi) values, predominantly metapelitic rutiles and mostly Proterozoic and Archaean detrital zircon ages, interpreted to be sourced from the Caledonides, and (ii) a Uralian Sand Type, characterised by a low compositional maturity, high CZi values, predominantly metamafic rutiles and Carboniferous zircon ages, sourced from the Uralian Orogeny. In addition, disparity in detrital zircon ages of the Uralian Sand Type with contiguous strata on the northern Barents Shelf reveals the presence of a Northern Uraloid Sand Type, interpreted to have been sourced from Taimyr and Severnaya Zemlya. As such, a coincidental system is inferred which delivered sand to the Northern Barents Shelf in the late Carnian/early Norian. Following the Early Norian Maximum Flooding Surface, a significant provenance change occurs. In response to Late Triassic/Early Jurassic hinterland rejuvenation, supply from the Uralian Orogen ceased and the northern Scandinavian (Caledonian) source became dominant, extending northwards out on to the southwest Barents Shelf. The data reveal a link between reservoir quality and sand type and illustrate how provenance played an important role in the development of clastic reservoirs within the Triassic of the Barents Shelf. 相似文献
16.
Mark Tomasso John R. Underhill Richard A. Hodgkinson Mike J. Young 《Marine and Petroleum Geology》2008,25(7):588-605
Interpretation of well-calibrated three-dimensional seismic volumes, sedimentological analysis and electrical well-log correlations from the Ninian and Alwyn North fields challenge the long-held view that Mid-Late Jurassic extensional faults in the East Shetland Basin represent a simple reactivation of older (Triassic) fault systems. Restoration for the effects of the younger, predominantly eastward-dipping, Mid-Late Jurassic structures clearly demonstrates that Triassic precursors had a steep, westerly dip. In contrast to the eastern flank of the Viking Graben (e.g. Troll and Oseberg areas), where the west-dipping Triassic structures are reutilised in the Mid-Late Jurassic, those of the East Shetland Basin have largely been dissected and rotated during the later event. Those west-dipping faults that did see later movement appear to have simply acted as minor antithetic structures to the throughgoing east-dipping ones.The Triassic normal fault patterns actively controlled sediment thicknesses and facies distribution within the Lunde and Teist Formations in the basin. Use of seismic stratigraphic surfaces, calibrated by biostratigraphy and chemostratigraphic markers, provides strong evidence that the Triassic depocentres are spatially offset from their Mid-Late Jurassic counterparts. The combination of structural, stratigraphic and sedimentary effects reveal the existence of an emergent deeper Triassic play opportunity in footwall locations to the Mid-Late Jurassic normal faults, which has the potential to extend the life of what is otherwise mature acreage. 相似文献
17.
东海陆架盆地是位于中国东部华南大陆边缘的一个中、新生代叠合盆地,具有较大油气潜力。目前东海陆架盆地油气的发现均来自于新生界,对中生代残留地层的各方面特征认识不足:在空间上通常集中于特定构造单元,且基本位于盆地西部;在时间上主要涉及白垩纪和侏罗纪,且多是定性或半定量的研究。本文在前人研究的基础上,收集、整理了研究区目前最新、最全的反射地震资料和钻井数据,从钻遇中生界井的标定出发,以地震资料的层序划分和解释为基础,进行残留地层的研究,空间上统一盆地东、西两大坳陷带,时间上统揽白垩纪、侏罗纪以及前侏罗纪三个时期。结果表明,东海陆架盆地中生代残留地层遭受了后期严重的剥蚀改造,总体呈现东厚西薄、南厚北薄的特征,残留地层范围随时间不断东扩。对比各时期残留地层平面展布特征,揭示了东海陆架盆地的演变过程:三叠纪时期盆地原型为被动大陆边缘坳陷型盆地,早、中侏罗世时期为活动大陆边缘弧前盆地,晚侏罗世—晚白垩世时期为大陆边缘弧后伸展盆地;与此相对应,古太平洋板块俯冲肇始于晚三叠世—早、中侏罗世时期,板块后撤始于晚侏罗世。东海陆架盆地在中生代的东侧边界位于钓鱼岛隆褶带的东侧。 相似文献
18.
地震多属性预测技术在南黄海二叠系至三叠系沉积分析中的应用 总被引：2，自引：0，他引：2
以往对南黄海盆地沉积相分析主要根据地震剖面的振幅、相位和频率进行地震相划分,再结合测井资料得到沉积相分布,而地震属性除了以上3种属性外,还包含着多种与沉积相有关的属性,以往对沉积相的分析未能充分利用这些地震属性信息.目前,南黄海盆地钻井资料较少,充分利用地震多属性信息对南黄海盆地三叠系下统青龙组—二叠系上统龙潭组、大隆... 相似文献
19.
Tilahun Mammo 《Marine and Petroleum Geology》2010,27(4):895-908
In Northern Ethiopia oil seepage could be traced flowing through fractured basalts at the Mechela river bed near Wereilu town. These rocks make up part of the huge volume of Ethiopia's Oligocene-Miocene Plateau basalts and associated rhyolites that cover most of the central and northern part of the country. They overlie the marine sedimentary formations of Triassic–Cretaceous age and constitute one of the largest visible flood basalts on the face of the earth.2-D and 3-D analyses of the gravity field have been performed to determine the structural pattern and subsurface density distributions beneath the thick volcanic sequences. The resulting images offer significant new insights into the structural pattern and geophysical characterization of the study area. A NW–SE elongated basin of significant dimension has been localized directly beneath the oil seep at Wereilu. The basin is a graben formed within and by the NW–SE trending structures of the Karroo rift system. A younger generation of faults in the NE–SW direction has affected the basin exerting significant control on the geometry and perhaps on the sedimentation pattern that might have played a major role in hydrocarbon accumulation and localization.The nature and thickness of the sub-volcanic sedimentary succession, attaining a significant thickness of more than 5 km, coupled with the overlying thick volcanic sequences providing the necessary thermal gradient for the maturation of the organic material create a favorable condition for the generation and accumulation of hydrocarbon deposit. 相似文献
20.
南海及周边部分地区特提斯构造遗迹:问题与思考 总被引：6，自引：1，他引：6
对全球二叠纪－三叠纪古气候特征的研究表明，东特提斯地区晚三叠世古气候标志具有带状分布的特征。北巴拉望地块卡拉棉群岛科龙岛的晚三叠世沉积中发育反映较干燥古气候特征的鲕状灰岩，因此在古气候特征方面，北巴拉望地块晚三叠世地层不能与华南和印支地块同期地层对比，而应该与印度地块北缘喜马拉雅地区（向西）和琉球群岛（向东）对比。根据该古气候分析，北巴拉望地块在晚三叠世时应该位于南部亚热带较干燥气候带内，其晚三叠世的古地理位置比印支地块更靠南。对南海及南海周边部分地特提斯构造遗迹的研究，将有助于深入了解南海北部陆缘区相关构造带的性质及正确恢复南海扩张之前该区的地质发展历史。南海北部陆缘区也是研究解决特提斯构造向东延伸问题以及特提斯构造－太平洋构造时空转化问题的关键地区。 相似文献