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1.
海拉尔盆地古地温研究   总被引:1,自引:0,他引:1  
海拉尔盆地作为大庆油田外围最有潜力的油气盆地之一,其古地温梯度以及古地温与油气的关系尚未进行系统研究。根据磷灰石裂变径迹法求取的古地温梯度为3.44~4.20℃/hm。其中乌尔逊凹陷古地温梯度与现今地温梯度接近,贝尔凹陷和呼和湖凹陷恢复的古地温梯度值高于现今地温梯度值。热史模拟表明海拉尔盆地最高古地温是在伊敏组沉积晚期90Ma达到。一类凹陷如乌尔逊凹陷属于持续埋藏型凹陷,中生代以来是一升温过程,在凹陷的中心部位现今地温是地层经历的最高地温,烃源岩热演化程度受现今地温场控制,现今持续生烃。另一类凹陷如贝尔凹陷和呼和湖凹陷,属于抬升剥蚀型凹陷,伊敏组沉积之后是一个降温过程,现今地温小于古地温,烃源岩热演化程度受古地温场控制。古地温演化史结合伊利石测年结果表明,伊敏组沉积晚期是海拉尔盆地一次非常重要的油气成藏期;古近纪以来为第二次成藏阶段,主要为早期形成油气藏的重新调整和二次生成的油气继续注入成藏。  相似文献   

2.
《地学前缘》2017,(3):137-148
鄂尔多斯盆地为大型含油气盆地,是我国重要的能源基地。盆地现今地温梯度为2.8℃/100m,属于中温型盆地。根据现今地层测温及地温梯度,编制了盆地3个重要烃源岩发育层位延长组长7段、石炭二叠系、奥陶系顶面现今地温分布图,分析了3个界面现今地温分布特征。根据收集及实测的奥陶系沥青反射率资料,编制了奥陶系顶面镜质体反射率等值线平面分布图。盆地不同层位的镜质体反射率值随着深度增加或层位变老,镜质体反射率值逐渐增高,在各地层分界面处不存在镜质体反射率(Ro)明显的错断。各构造单元镜质体反射率(Ro)与深度关系曲线图差异主要表现为曲线斜率的差异及曲线接近地表起始值的差异,这两项差异反映了地温梯度及后期剥蚀厚度的差异。不同层位的镜质体反射率的高值区均位于盆地南部的庆阳—富县—延安—吴旗一带,盆地南部不同层位镜质体反射率高值区的存在表明盆地南部热演化程度高,存在热异常。盆地热演化史恢复表明早白垩世鄂尔多斯盆地发生过一期构造热事件,地层在早白垩世末达到最大古地温。早白垩世以后,鄂尔多斯盆地整体大幅度抬升剥蚀,地温梯度减小,地层冷却降温。现今地层温度远小于在早白垩世末达到的最大古地温,油气的生成主要受古地温控制。早白垩世的构造热事件控制了上、下古生界、中生界3套主要烃源岩油气的主要生成、成藏期。  相似文献   

3.
田涛  任战利  吴晓青  陈玉林 《地质科学》2013,48(4):1258-1270
非洲G盆地是受中非剪切带影响而发育形成的典型被动裂谷盆地,其南部凹陷带为盆地主要油源区。为进一步明确G盆地油气勘探方向,需开展盆地南部凹陷热演化史及油气成藏方面的研究。油层测温表明,南部凹陷现今平均地温梯度为3.9 ℃/100 m,属于中温型地温场。根据镜质体反射率、包裹体测温恢复了G盆地凹陷带古地温演化史,研究表明G盆地凹陷白垩纪古地温梯度为2.4~3.77 ℃/100 m,古地温梯度低于现今地温梯度。古地温恢复及热史模拟表明最高地温是在现今达到的,下白垩统烃源岩热演化程度主要受现今地温场控制。包裹体均一温度分析表明G盆地南部凹陷存在两次流体作用事件,分别发生在晚白垩世早期(96.0~87.0 Ma)及第四纪(3.0~0 Ma)。下白垩统油气的主要成藏期在晚白垩世早期。  相似文献   

4.
海拉尔盆地贝尔凹陷热演化史与油气关系研究   总被引:1,自引:0,他引:1  
贝尔凹陷是是海拉尔盆地内勘探程度较高的一个南部凹陷,该凹陷沉积厚度大,地层发育全,生油条件十分优越,是海拉尔盆地主要产油气凹陷.主要烃源岩层是南屯组,其次是大磨拐河组和铜钵庙组.根据镜质组反射率、包裹体测温和磷灰石裂变径迹法恢复的贝尔凹陷古地温演化史表明贝尔凹陷早白垩世古地温梯度可达3.7~5.8℃/100m,高于现今...  相似文献   

5.
内蒙古海拉尔盆地乌尔逊凹陷热演化史   总被引:2,自引:2,他引:0  
乌尔逊凹陷是内蒙古海拉尔盆地内勘验程度较高的一个南部凹陷,该凹陷沉积厚度大,地层发育全,生油条件十分优越,是海拉尔盆地主要产油气凹陷。主要烃源岩层是南屯组,其次是铜钵庙组和大磨拐河组。根据磷灰石裂变径迹法恢复的乌尔逊凹陷早白垩世古地温梯度为3.44℃/hm,接近现今地温梯度3.3℃/hm。古地温恢复及热演化史模拟表明,乌尔逊凹陷中生代以来经历了一个升温过程,下白垩统烃源岩热演化程度主要受现今地温场控制。热演化史与油气关系研究结合伊利石测年结果表明,乌尔逊凹陷油气成藏期主要有两期,为早白垩世晚期及古近纪以来,且以早白垩世晚期为主要成藏期;古近纪以来为第二期成藏阶段,烃源岩进入第二次生油高峰期。第二次成藏时期对乌尔逊凹陷油气藏的形成起着重要作用,是制约油气富集的重要因素。  相似文献   

6.
昌潍坳陷新生代古地温分析   总被引:1,自引:0,他引:1  
昌潍坳陷是胜利油田重要的外围勘探区域,确定其古地温对研究其生烃史和油气成藏史具有重要的意义.综合应用镜质体反射率和磷灰石裂变径迹方法反演得到了其新生代热史演化规律,得出昌潍坳陷新生代古地温梯度演化趋势从古到今逐步降低的结论.同时间接证明了综合镜质体反射率和磷灰石裂变径迹反演东部简单盆地热史是一种行之有效的方法.  相似文献   

7.
海拉尔盆地呼和湖凹陷热演化史与油气关系   总被引:4,自引:3,他引:4       下载免费PDF全文
呼和湖凹陷现今地温梯度为3.54℃/100m,属于中温型地温场。根据镜质体反射率、包裹体测温和磷灰石裂变径迹法恢复了呼和湖凹陷古地温演化史,研究表明呼和湖凹陷早白垩世古地温梯度可达3.7~6.5℃/100m,古地温梯度高于现今地温梯度,古地温高于今地温。古地温恢复及热史模拟表明最高古地温是在早白垩世晚期达到的,下白垩统烃源岩热演化程度主要受古地温场控制。热演化史与油气关系研究表明呼和湖凹陷油气生成期主要有两期,分别是早白垩世晚期及古近纪以来,且以早白垩世晚期为主要成藏期,古近纪以来由于目的层温度降低生烃强度减弱。  相似文献   

8.
韩伟  姜亭  李玉宏  魏建设 《地质通报》2011,30(6):911-915
分析了额济纳旗及其邻区二叠系烃源岩热演化史与油气生成的关系。根据镜质组反射率、包裹体均一温度、磷灰石裂变径迹等资料得出研究区达到最大埋深时的古地温梯度,分析额济纳旗地区热演化史的信息,进一步研究了热演化与油气生成的关系。研究结果表明,额济纳旗地区在白垩纪达到最大埋深,古地温梯度为4.1~5.5℃/100m。通过与邻区查干凹陷比较分析,认为额济纳旗地区古地温梯度高于现今的地温梯度,二叠系烃源岩热演化程度主要受古地温场的控制。热演化史与油气关系的研究结果表明,额济纳旗部分地区二叠系烃源岩在晚二叠世已进入油气生成期,生烃阶段以干气为主,在早白垩世热演化程度达到最高。  相似文献   

9.
鄂尔多斯盆地黄陵、东胜地区地温场对比   总被引:2,自引:0,他引:2  
鄂尔多斯盆地黄陵、东胜铀矿区分别处于盆地南部渭北隆起的北侧边缘和盆地北部伊盟隆起的东部,赋矿层位都是中侏罗统直罗组。盆地南、北铀矿区在现今地温场及古地温场都存在明显差异,南部现今大地热值及热演化程度明显高于北部。对于下侏罗统延安组和石炭—二叠系煤层,黄陵地区镜质体反射率都高于东胜地区。通过镜质体反射率资料得出同一埋深的一套地层经历的最大古地温和对应的古地温梯度也有南部高于北部的现象。由于早白垩世后期盆地普遍整体抬升使得现今地温相对古地温降低,南部黄陵地区抬升剥蚀量大于北部东胜地区,导致古、今地温差异也大于后者。盆地南部庆阳—富县一带局部构造热运动,导致南部异常地温场的形成,使得南部热演化程度高于北部。  相似文献   

10.
苏北盆地金湖凹陷热史与成藏期判识   总被引:3,自引:0,他引:3  
在镜质体反射率和磷灰石裂变径迹系统测试分析的基础上,对金湖凹陷西斜坡和卞闵杨构造带进行古地温梯度计算和热史恢复.根据镜质体反射率计算出西斜坡的古地温范围介于45.6~128.4℃,古地温梯度为45.5℃/km;卞闵杨构造带古地温为26.4~120.3℃,古地温梯度为42.7℃/km.根据磷灰石裂变径迹计算出西斜坡古地温...  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

13.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

14.
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931.  相似文献   

15.
16.
PALEONTOLOGY     
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.)  相似文献   

17.
正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.)  相似文献   

18.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.)  相似文献   

19.
PETROLOGY     
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus.,  相似文献   

20.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an  相似文献   

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