Neotectonics of Turkey – a synthesis

Abstract

Turkey forms one of the most actively deforming regions in the world and has a long history of devastating earthquakes. The belter understanding of its neotectonic features and active tectonics would provide insight, not only for the country but also for the entire Eastern Mediterranean region. Active tectonics of Turkey is the manifestation of collisional intracontinental convergence- and tectonic escape-related deformation since the Early Pliocene (~5 Ma). Three major structures govern the neotectonics of Turkey; they are dextral North Anatolian Fault Zone (NAFZ), sinistral East Anatolian Fault Zone (EAFZ) and the Aegean–Cyprean Arc. Also, sinistral Dead Sea Fault Zone has an important role. The Anatolian wedge between the NAFZ and EAFZ moves westward away from the eastern Anatolia, the collision zone between the Arabian and the Eurasian plates. Ongoing deformation along, and mutual interaction among them has resulted in four distinct neotectonic provinces, namely the East Anatolian contractional, the North Anatolian, the Central Anatolian ‘Ova’ and the West Anatolian extensional provinces. Each province is characterized by its unique structural elements, and forms an excellent laboratory to study active strike-slip, normal and reverse faulting and the associated basin formation. © 2001 Éditions scientifiques et médicales Elsevier SAS     

合肥盆地中生界地层的热演化程度——伊利石结晶度的指示

合肥盆地中生界地层的热演化程度以往了解的十分有限。通过盆地内中生界地层一系列自生伊利石结晶度值的测试,揭示地表白垩系地层多数处于成岩作用的晚期,少部分处于成岩作用中期,分别指示其中有机质进入了中—高成熟期或成熟期。钻井中1000m以上地层也处于成岩作用的中期或晚期,类似于地表样品。而钻井中1000m以下所有中生界地层都进入了埋藏变质阶段,指示着有机质的过成熟期。其中1000～3000m深的热演化温度为200～250℃。而3000m以下的热演化温度基本上为250～300℃。这些测试结果为合肥盆地今后的油气远景评价与勘探提供了重要的信息。     

Very low-grade metamorphism of the Meso-Neoproterozoic and the Lower Paleozoic along the profile from Huangtudian to Xianxi in the central-northern part of Hunan Province,China

The Lengjiaxi and Banxi groups of the Meso-Neoproterozoic and the Sinian to the Lower Paleozoic occur along the profile from Huangtudian to Xianxi in the central-northern Hunan Province, China. Previous studies on the metamorphism around the area did not …     

川西北壤塘地区三叠纪西康群极低级变质作用

通过区域地质调查和伊利石的结晶度指数、晶格参数（bo）的测定，揭示川西北壤塘地区三叠纪西康群遭受了区域极低级变质作用，进一步讨论区域极低级变质作用与构造变形的关系，并指出区域极低级变质作用是成岩－埋藏变质作用（造山前）和同造山变质作用的综合结果。     

阳山伊利石表面化学特性及化合态

用非连续酸碱滴定法和氯化铵-乙醇法测定表明,2M1型伊利石的pHzpc＝6.5,阳离子交换量CEC＝11.0×105mol/g.应用恒容双表面位模式,通过多元非线性拟合计算表明,伊利石表面铝醇基＞AlOH浓度N1,Al＝4.0×10-5mol/g,质子化常数pKal,Al＝5.95和pKa2,Al＝9.45,硅醇基＞SiOH的Nt.si＝0.53×10-5mol/g,pKa2,si＝3.85.同时发现,在伊利石表面酸碱特性研究中,当溶液pH＜4时,须考虑伊利石表面阳离子与溶液质子之间的交换反应,测定表明交换反应常数Kx＝0.42.     

沉积岩中成岩伊利石年龄测定研究进展

伊利石的形成与盆地的沉积和热演化有密切关系，它可以指示油气的形成时代，因此测定成岩伊利石的形成年龄是一个重要的课题。碎屑伊利石往往与成岩伊利石共生，导致样品的年龄远远大于成岩伊利石的真实年龄。为了有效地分离成岩和碎屑伊利石，需要使用IAA法和烷基胺阳离子取代法等，结合真空密封法等其他技术，能够得到更好的效果。并介绍了国外伊利石定年的研究现状。     

利用自生伊利石K-Ar定年分析烃类进入储集层的时间

烃类流体注入储层聚集成藏导致储层中自生矿物形成的抑或中止，成岩矿物同位素地质年代学分析提供了成岩矿物形成的准确时间，成岩事件年代学研究可用于定量分析油气藏形成时间。砂岩储层中自生伊利石仅在流动的富钾孔隙不介质环境下才能形成，烃类流体注入储层后伊利石形成便会中止，因此，烃类流体进入储层时间不可能早于自生伊利石的形成时间。     

Silurian-Devonian and Jurassic Thermal Events in the Ordos Basin, China: Indications from K-Ar Dating on Illites

In the Ordos basin, two distinct thermal events of different ages have been identified for the first time by means of K-Ar dating combined with illite crystallinity analysis. For the Late Triassic and Late Permian samples, the K-Ar ages of the < 0.2μm fractions (159-173 Ma) reflect an illitization age related to the Yanshanian movement and indicate a short thermal event in the Middle Jurassic; the K-Ar ages of the <2 μm fractions (210-308 Ma) are interpreted as mixed ages of detrital material and authigenic illites. The K-Ar ages of both < 0.2μm and < 2μm fractions of a Middle Cambrian sample (368 Ma and 419 Ma) correspond to the ages of the metamorphism and earliest granite intrusion in the northern Caledonian Qinling fold zone (380-420 Ma) and show a thermal event during Silurian-Devonian time.     

鄂尔多斯盆地志留—泥盆纪和侏罗纪热事件—伊利石K—Ar年龄证据

利用伊利石K-Ar测年法,结合伊利石结晶度分析,首次在鄂尔多斯盆地确定出两期不同时代热事件。晚三叠世和晚二叠世<0.2μm粒级的岩石样品的K-Ar年龄(159-173Ma)反映了与燕山运动有关的伊利石化年龄,指示有一期中侏罗世的热事件;其<2μm粒级的K-Ar年龄(210-308Ma)则被解释为碎屑物和自生伊利石的混合年龄。中寒武世<0.2μm和<2μm粒级的岩石样品K-Ar年龄(368Ma与419Ma)对应于北秦岭加里东褶皱带变质作用与最早期花岗岩侵入的时代(380-420Ma),表明在志留-泥盆纪发生了一期热事件。     

合肥盆地烃源岩有机质热演化历史分析

利用镜质体反射率资料及其定量恢复的合肥盆地的古地温结合伊利石结晶度测定系统研究了盆地石炭-二叠系以来的热演化史,在此基础上分析了石炭-二叠系、下侏罗系、中上侏罗系、白垩系、古近系的烃源岩有机质的热演化程度及热演化史,结果表明合肥盆地C-P系呈现为高成熟阶段,并在下侏罗统沉积之后开始进入生油门限,在上侏罗统沉积后地温曾达245℃,而在白垩纪中期(朱巷组沉积后)最大古地温度达到过305℃指示进入了过成熟阶段。下侏罗统防虎山组Ro值和伊利石结晶度也显示了较高的热演化程度,在中侏罗统沉积后开始进入生油门限,在早白垩世朱巷组沉积后达到了最高的热演化程度,最大古地温达260℃。中-上侏罗统随着下白垩统朱巷组的沉积而进入生油门限,在下白垩统沉积之后达到了最大的古地温度,分别为225℃、230℃,指示开始进入过成熟阶段,朱巷组最大埋藏温度出现在早白垩世末,达到了110～120℃,指示进入了成熟期。在上覆古近系沉积后曾达到最大古地温(110～160℃),显示进入了成熟阶段。古近系定远组未进入成熟阶段,最大古地温出现在定远组沉积之后,但小于50℃。