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1.
This paper features the structural evolution of the eastern margin of Eurasia in Late Mesozoic and Cenozoic.It is characterized by three stages of development: the riftogenic stage (Jurassic-Early Cretaceous), the platform stage (Late Cretaceous) and the neotectonic one (Paleogene-Quarternary). The boundaries between these stages are distinctly fixed by the geological time limits of planetary range. It is demonstrated that the riftogenic and neotectonic stages were characterized by a high degree of geodynamic activity, and the platform one by a decrease in contrast of tectonic movements. The main river net was formed in the Early Cretaceous and in the Neogene. It experienced a serious reconstruction accompanied by the formation of the Amur River valley being similar to the modem one.  相似文献   
2.
王先美 《地质学报》2008,82(1):1258-1273
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   
3.
In distribution areas of the Pekul’neiveem and Chirynai formations customary distinguishable in the Koryak Upland, complicated tectonostratigraphic units are composed of alternating thrust sheets of different lithologic composition and age, which are juxtaposed because of widespread thrust faulting, as is proved by the radiolarian analysis. Nineteen radiolarian assemblages of different age are first established here in the Lower Jurassic-Hauterivian succession of siliceous-volcanogenic sediments. In the Lower Jurassic interval, the lower and upper Hettangian, lower and upper Sinemurian, and Pliensbachian beds are recognized. Paleontological characterization is also presented for the Aalenian (or Toarcian?-Aalenian), upper Bajocian, lower and upper Bathonian, and Callovian beds of the Middle Jurassic. Within the Upper Jurassic, the Oxfordian-early Kimmeridgian, late Kimmeridgian-early Tithonian, Tithonian, and late Tithonian-early Berriasian radiolarian assemblages are distinguished. The late Berriasian-early Valanginian, middle-late Valanginian, and Hauterivian radiolarian assemblages are first recognized or compositionally revised. Radiolarians and lithofacies data are used to correlate the tectonostratigraphic units and individualize the jasper-alkali basaltic (lower Hettangian), chert-terrigenous (Hettangian-Sinemurian), jasper-cherty (Pliensbachian-Aalenian), jasper (Bajocian-Hauterivian), jasper-basaltic (upper Bajocian-Valanginian), Fe-Ti basaltic (upper Bajocian-Bathonian), tuffitejasper-basaltic (Bathonian-Hauterivian), and terrigenous-volcanogenic (Bajocian-Valanginian) sequences. The correlation results are extrapolated into other continental areas flanking the Pacific, i.e., to the western Kamchatka, northern and northwestern coastal areas of the Sea of Okhotsk, where the analogous radiolarian assemblages are characteristic of comparable allochthonous units of terrigenous-siliceous-volcanogenic sediments.  相似文献   
4.
郯庐断裂带及其周缘中新生代盆地发育特征   总被引:19,自引:2,他引:19  
郯庐断裂带作为中国东部滨太平洋地区一条巨型走滑构造带,对其周缘中、新生代盆地的发育、演化起着重要的控制作用。随着太平洋板块俯冲方向从NNW向NW到NWW的变化,郯庐断裂带的活动方式逐步从中生代左行走滑-左行斜向滑动过渡到早第三纪以左行斜向-倾向滑动,晚第三纪-第四纪转为倾滑-右行斜向滑动-右行走滑。走滑活动经历了一个循序渐进的周期演变过程。随着郯庐断裂活动方式的演变,其周缘中、新生代盆地的发育逐渐向北迁移,其中南段周缘盆地主要为中生代盆地,中段周缘盆地主要为中、新生代叠加盆地,中北段周缘盆地主要为早第三纪盆地。每个盆地都经历了拉分(伸展)裂陷到挤压反转的演化过程。此外,在同一时期、同一区域剪切应力场作用下,不同区段因其走向变化导致局部应力场变化,在增压弯曲部位发生会聚、挤压、隆升;而释压拉张部位发生离散、伸展、沉降,从而盆地发育。  相似文献   
5.
黄海海域陆相中生界油气远景   总被引:8,自引:1,他引:8  
黄海海域油气勘探已40余载,尚未实现油气突破,其找油前景引起石油地质学家的极大关注。根据前人的认识和最新研究成果,结合邻区油气地化资料,探讨了黄海海域中生界地层生、储、盖特征,特别是白垩系,它分布广,厚度大,烃源岩达到较好生油岩标准,并且生、储、盖组合理想,中生界是该区下部油气勘探首选目标。  相似文献   
6.
The data from a recent magnetic compilation by Verhoefet al. (1991) off west Africa were used in combination with data in the western Atlantic to review the Mesozoic plate kinematic evolution of the central North Atlantic. The magnetic profile data were analyzed to identify the M-series sea floor spreading anomalies on the African plate. Oceanic fracture zones were identified from magnetic anomalies and seismic and gravity measurements. The identified sea floor spreading anomalies on the African plate were combined with those on the North American plate to calculate reconstruction poles for this part of the central Atlantic. The total separation poles derived in this paper describe a smooth curve, suggesting that the motion of the pole through time was continuous. Although the new sea floor spreading history differs only slightly from the one presented by Klitgord and Schouten (1986), it predicts smoother flowlines. On the other hand, the sea floor spreading history as depicted by the flowlines for the eastern central Atlantic deviates substantially from that of Sundvik and Larson (1988). A revised spreading history is also presented for the Cretaceous Magnetic Quiet Zone, where large changes in spreading direction occurred, that can not be resolved when fitting magnetic isochrons only, but which are evident from fracture zone traces and directions of sea floor spreading topography.Deceased 11 November 1991  相似文献   
7.
大港油田官142断块巨厚砂岩的储层流动单元   总被引:1,自引:1,他引:0  
以黄骅坳陷官142断块中生界油藏为例,探讨巨厚砂岩储层流动单元的研究方法。巨厚砂岩储层流动单元研究包括两个层次,一为确定渗流屏障和连通体的分布,二为连通体内部储层渗流差异分析。研究表明,官142断块渗流屏障主要有泥质屏障、钙质砂岩胶结屏障和钙质砂砾岩胶结屏障3种类型。通过对连通体内部砂体渗流差异性分析,将连通体划分为3类流动单元。其中A类流动单元以粗孔、粗喉类型为主,渗流性能好,吸水强度大;B类流动单元储层为中孔、中喉型,渗流性能中等,吸水强度次之;C类流动单元储层多为粉细砂岩、砂砾岩或钙质胶结稍差的储层,吸水强度较差。通过流动单元的划分与研究,对预测该区的剩余油分布规律和优化调整方案提供依据。  相似文献   
8.
辽东南地区晚中生代地层发育不甚完全,具有两期盆地叠合演化的特征,即早中侏罗世和早白垩世两个演化阶段,经历了2次伸展裂陷和2次挤压反转。在详细研究辽东南地区各盆地岩石地层序列、生物化石组合特征、年代地层格架以及区域地层对比的基础上,讨论了盆地的演化阶段和演化规律,指出是古太平洋板块向东亚大陆边缘不同方向的俯冲与走滑,以及来自北方西伯利亚板块的持续碰撞挤压的联合构造应力场制约了中国东北地区晚中生代盆地的裂陷过程和构造反转的演化,进而为揭示华北克拉通晚中生代岩石圈演化的动力学机制提供参考依据。  相似文献   
9.
Based on the determination of composition of volcanic volatiles and petrologic estimation of the total mass of volatiles erupted, we showed important advances in the study of the impact of Mesozoic and Cenozoic volcanic activities on paleo-environmental changes in China. The volcanic activities include western Liaoning and Zhangjiakou Mesozoic intermediate-acidic explosive eruptions, southern Tibet and Shanwang Cenozoic volcanism, and Mt. Changbai volcanic eruption around one thousand years ago. The paper predominantly discusses the earth’s surface temperature changes, ozone depletion, acidic rain formation and mass mortalities of vertebrate induced by the Mesozoic and Cenozoic volcanism in China. __________ Translated from Bulletin of Mineralogy, Petrology and Geochemistry, 2007, 26(4): 319–322 [译自: 矿物岩石地球化学通报]  相似文献   
10.
邵于庄煤炭勘查区新生界松散层厚度较厚,下伏为二叠系含煤地层,可采煤层多。区内含、隔水层组成复杂,由四个含水层和三个隔水层组成。通过对含水层水文地质条件分析,提出了第一、二含水层是矿区的主要供水水源,为保证未来建设和开采时的生活用水和工业用水,应做好水源的保护工作;同时指明了第四含水层是浅部煤组开采的主要补给水源,在煤矿设计和开采过程中,应重点予以防治。  相似文献   
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