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1.
G. Lain Ellis Glenn A. Goodfriend James T. Abbott P. E. Hare David W. Von Endt 《Geoarchaeology》1996,11(3):189-213
Detailed racemization analyses were carried out on samples of the land snail Rabdotus mooreanus from archaeological sites at Fort Hood, in central Texas. D -alloisoleucine/L -isoleucine (A/I) values were determined for 260 individual shells from 29 proveniences, including sites in alluvium, colluvium, and rockshelters, as well as burned rock middens. A/I values show a good correlation with radiocarbon age, and so provide reasonably precise estimates of ages. Analyses indicate the presence of redeposited material in a large number of proveniences. These result from sedimentary processes involved in burial of the sites as well as from later disturbance (aboriginal or recent) of site stratigraphy. Because amino acid racemization analyses are relatively easy to carry out, this method lends itself to very detailed chronostratigraphic analyses of archaeological sites, thus permitting assessment of site integrity and assisting in the interpretation of site formation processes. © 1996 John Wiley & Sons, Inc. 相似文献
2.
基于笔者多年对鄂尔多斯盆地及周缘地区晚古生代研究成果,结合野外剖面实测、钻井资料分析、地层学与层序地层学、地球化学、年代学等研究结果,从岩性特征、地层厚度、地层接触关系、物源分析、沉积相类型多方面进行对比研究,认为鄂尔多斯盆地及周缘地区上古生界是华北地台的一部分,因此,其沉积充填及沉积演化研究必须置于晚古生代大华北盆地之中。在此研究基础上绘制了晚古生代各组鄂尔多斯盆地及周缘沉积相平面展布图,亮点是向东部和南部进行了扩张,并详述了晚古生代沉积演化过程,为该时期华北地台原始沉积面貌的恢复提供了新的依据。 相似文献
3.
基于笔者多年对鄂尔多斯盆地及周缘地区晚古生代研究成果,结合野外剖面实测、钻井资料分析、地层学与层序地层学、地球化学、年代学等研究结果,从岩性特征、地层厚度、地层接触关系、物源分析、沉积相类型多方面进行对比研究,认为鄂尔多斯盆地及周缘地区上古生界是华北地台的一部分,因此,其沉积充填及沉积演化研究必须置于晚古生代大华北盆地之中。在此研究基础上绘制了晚古生代各组鄂尔多斯盆地及周缘沉积相平面展布图,亮点是向东部和南部进行了扩张,并详述了晚古生代沉积演化过程,为该时期华北地台原始沉积面貌的恢复提供了新的依据。 相似文献
4.
Evaluation of the relative roles of global versus local sedimentary controls on Middle to Late Pleistocene formation of continental margin strata,Canterbury Basin,New Zealand 
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下载免费PDF全文 Tania Villaseñor John M. Jaeger Kathleen M. Marsaglia Greg H. Browne 《Sedimentology》2015,62(4):1118-1148
Determining the relative influence of eustasy versus local sedimentary processes on strata formation is a fundamental challenge in the study of continental margin stratigraphy. In this paper, the relative contribution of these factors on continental margin evolution during the Middle to Late Pleistocene is evaluated using samples from Integrated Ocean Drilling Program Expedition 317. Core‐logging, biostratigraphy and quantitative X‐ray diffraction mineralogy are used to delineate continental shelf sedimentary systems. Major lithological unconformities bound stratigraphic sequences that contain recurring compositional patterns and that resemble other examples of Middle to Upper Pleistocene sequences. However, a preliminary chronology suggests that sequence boundary formation cannot be linked ‘one to one’ with eustatic cycles and therefore these sequences can contain multiple ca 100 ka eustatic cycles. Smaller amplitude, higher frequency transitions in sediment composition are interpreted as stratigraphic sequences driven by more rapid perturbations in the interplay of accommodation and sediment supply; their stratigraphy is variable in time and across the shelf, suggesting a strong influence of local sedimentary forcing in their formation. Changes in sediment composition after the Middle Pleistocene Transition indicate that sediment transfer from onshore sources in the glaciated Southern Alps to the middle‐shelf occurred over a single 100 ka glacio‐eustatic cycle, with an additional 100 ka lag before the mineralogical signal was preserved on the outer‐shelf. This phenomenon is coincident with rapid shelf progradation in this basin, suggesting a causal relation between across‐shelf sediment transport and margin progradation. This is one of very few studies that provide insights at the core scale into the processes driving continental margin evolution during the Middle to Late Pleistocene. This work shows that compositional changes in mud‐dominated successions can lead to a sequence stratigraphic interpretation and the identification of high‐frequency sequences, which may not be possible using a conventional stratigraphic approach. 相似文献
5.
有机地球化学参数在层序划分对比中的应用——以冀中拗陷束鹿凹陷沙三下亚段为例 总被引：1，自引：0，他引：1
深水细粒沉积层系的层序地层单元细分和对比,是建立合理的层序地层格架的关键,也是进行深水区岩性油气藏勘探开发的一项重要基础研究工作。但往往由于细粒沉积层系层序地层单元划分标志不明显,其划分对比较为困难,这也是层序地层学研究的难点。依据高分辨率层序地层学原理,从沉积层序的成因及其表现入手,应用表征沉积环境或沉积物特征的有机地球化学参数在纵向上的周期性变化规律,对渤海湾盆地冀中坳陷束鹿凹陷沙三段下亚段半深湖—深湖相泥灰岩沉积进行了层序地层单元划分和对比,较好地识别出了4级旋回与5级旋回,为建立高分辨率层序地层格架奠定了基础。 相似文献
6.
海拉尔盆地呼和湖凹陷白垩系层序地层特征及沉积演化 总被引：4，自引：0，他引：4
以层序地层学理论为指导,通过对全凹陷范围内的地震、钻井、测井、岩心以及古生物等资料的综合研究,建立了呼和湖凹陷白垩系层序地层格架。将呼和湖凹陷白垩系划分为3个一级层序(TSq1-TSq3)、5个二级层序(Ⅰ-Ⅴ)、8个三级层序(Sq1-Sq8);并在层序格架内进行沉积相划分和沉积体系研究,确定该区主要发育冲积扇、扇三角洲、辫状河三角洲、湖底扇和湖泊沉积等沉积体系。其中冲积扇沉积体系主要分布在早期Sq1层序中;扇三角洲沉积体系主要分布在Sq2层序的南部和Sq5层序的北部;而辫状河三角洲沉积体系在Sq3、Sq4层序中尤其发育,并在Sq2层序的北部也有所发育;湖底扇沉积体系主要发育在Sq2、Sq3和Sq4层序的洼陷带;湖泊沉积体系主要发育在各层序的洼陷带。沉积体系在平面与纵向上的演化受古构造与古地貌的控制,呼和湖凹陷南部沉积砂体为较有利的勘探区域。 相似文献
7.
层序地层分析与海平面变化研究—进展与争论 总被引：9，自引：0，他引：9
当代地质学之热点层序地层分析提出于70年代,至今正在成为被广泛注意和应用的学科。在石油勘探领域应用这一新的概念体系和方法已经为储集砂体的预测带来了战略性的变化,并取得了重要成就,特别是低位体系域底界面上的深切谷充填砂体的预测和发现。但是目前也存在着理论上的尖锐争论,其中主要针对全球海平面变化问题,许多学者根据新的资料和模拟结果论证了层序地层样式受控于构造、海平面变化、沉积物补给等多种因素;在许多地区证实的相对海平面变化事件不能轻易地当作全球性事件去进行对比。本文选择了一些重要的代表性著作以及1992年AAPG年会和在北美考察所获信息针对主要的进展和争论进行了综述。 相似文献
8.
《Gondwana Research》2008,13(4):560-565
The method of sequence stratigraphy requires the application of the same workflow and principles irrespective of the age of strata under analysis. In that respect, its application to Precambrian successions is similar to the approach used for Phanerozoic case studies. Differences, however, are recorded in terms of the preservation potential and the amount of data available for analysis; the rates and intensities of the allogenic controls on sedimentation; the environmental conditions and related physical processes; and the evolution of competing groups of organisms and associated biogenic processes. The combined effect of these contrasting aspects accounts for differences in the architecture of depositional sequences, particularly with respect to the relative contributions of various systems tracts to the makeup of a sequence.The application of sequence stratigraphy to Precambrian basins has considerably enlarged the perspective on the fundamental principles governing the processes of sedimentary basin formation and the mechanisms controlling stratigraphic cyclicity in the rock record. These first-order principles are perhaps the most important contribution of Precambrian research to sequence stratigraphy. At the broader scale of Earth's geological history, the tectonic regimes governing the formation and evolution of sedimentary basins are shown to have been much more erratic in terms of nature and rates than originally inferred solely from the study of the Phanerozoic record. This provides important clues with respect to the criteria that should be involved in the hierarchy system of classification of stratigraphic sequences and bounding surfaces. 相似文献
9.
10.
沾化凹陷垦西地区新近系馆陶组沉积微相研究 总被引：1，自引：0，他引：1
油田开发阶段的精细油藏描述,要进行小层沉积微相的研究,阐明小层单元沉积微相特征,为相关开发研究奠定必要的沉积学基础.以传统沉积学和高精度层序地层学理论为指导,通过岩心观察和测井相分析,进而应用油藏描述技术中的沉积微相分析方法,从标准井测井沉积微相分析到全区多井对比,对垦西油田K71断块区新近系馆陶组储层的沉积微相类型及... 相似文献
11.
利用沉积学及层序地层学方法,通过对章丘煤田主要构造单元单井沉积相、层序地层分析,将章丘煤田石炭二叠纪含煤岩系的本溪组、太原组、山西组划分为1个一级盆地层序、2个二级构造层序、3个三级层序。在层序内部识别最大湖泛面或与之相当的沉积转换面,划分体系域,并重点对三级层序的划分进行研究。研究认为：三级层序Ⅰ发育高水位体系域和海侵体系域,主要由潮坪沉积体系、障壁-泻湖沉积体系和碳酸盐台地沉积体系组成;层序Ⅱ发育海侵体系域和高水位体系域,主要由潮坪体系、滨外台地体系和障壁-泻湖沉积体系组成;层序Ⅲ中低水位体系域、海侵体系域、高水位体系域都有较好发育,主要由浅水曲流河三角洲沉积体系组成。 相似文献
12.
应用高分辨率层序地层学和沉积学的原理与方法,综合岩心、钻井以及测井和地震资料,对鄂尔多斯盆地南部上三叠统延长组进行了深入的研究,识别出5个层序界面,划分出4个三级层序和11个四级层序,建立了鄂尔多斯盆地南部上三叠统延长组层序地层格架。在研究区识别出曲流河三角洲、辫状河三角洲、深水重力流和湖泊4种沉积相。分析了层序格架内沉积相时空展布特征,揭示了层序格架内沉积相的时空演化规律,归纳了层序格架内砂体发育与展布的特点。讨论了层序界线划分与以往地层界的区别及其实际意义,探讨了重力流沉积对鄂尔多斯盆地油气勘探的重大意义。 相似文献
13.
层序地层是在一个等时地质年代格架内从三维空间上认识一个有成因联系的沉积组合体，层序内部沉积地质体的性质、叠置关系和沉积相演变与海平面升降周期变化有对应关系。对滇黔桂地区晚震量世陡山沱期层序地层研究，笔者在上扬子浅海区对晋宁王家湾上震量统剖面进行实测，拟建立浅海区基干层序剖面，并把陡山沱组划分为一个2级层序和四个3级层序；在深海区对广西灵川西岭剖面进行实测，拟建立深海地区的基干层序剖面。然后在研究区进行辅助对比剖面的观测，以编制该区二级层序海侵体系域和高水位体系域的构造－层序岩相古地理图，通过这些研究，使人们从另一个角度去揭示和认识谝我在陡山沱期的构造运动、沉积物组合特征与海平面变化的关系，从而更进一步弄清该区的时空演化特征。 相似文献
14.
The method of sequence stratigraphy requires the application of the same workflow and principles irrespective of the age of strata under analysis. In that respect, its application to Precambrian successions is similar to the approach used for Phanerozoic case studies. Differences, however, are recorded in terms of the preservation potential and the amount of data available for analysis; the rates and intensities of the allogenic controls on sedimentation; the environmental conditions and related physical processes; and the evolution of competing groups of organisms and associated biogenic processes. The combined effect of these contrasting aspects accounts for differences in the architecture of depositional sequences, particularly with respect to the relative contributions of various systems tracts to the makeup of a sequence.
The application of sequence stratigraphy to Precambrian basins has considerably enlarged the perspective on the fundamental principles governing the processes of sedimentary basin formation and the mechanisms controlling stratigraphic cyclicity in the rock record. These first-order principles are perhaps the most important contribution of Precambrian research to sequence stratigraphy. At the broader scale of Earth's geological history, the tectonic regimes governing the formation and evolution of sedimentary basins are shown to have been much more erratic in terms of nature and rates than originally inferred solely from the study of the Phanerozoic record. This provides important clues with respect to the criteria that should be involved in the hierarchy system of classification of stratigraphic sequences and bounding surfaces. 相似文献
15.
河流地质考古学是基于地层研究河流和考古遗址之间关系的学科.近年来我们在河南省内黄县开展的河流地质考古研究揭示了黄河复杂的演化历史,在此基础上进一步探讨了古代人类活动与周围环境的相互作用.本文主要介绍了2010~2016年我们在河南省内黄县3个全新世遗址(岸上、三杨庄和大张龙村)的地质考古工作中所取得的成果.研究区域内遗址的地层记录表明,许多考古遗址被深埋于地下,并可能影响了3000 a B.P.以来的河流沉积过程.我们在岸上遗址发掘了A、B、C、D共4处青铜时代的沟渠遗迹,这些沟渠的堆筑可能影响了后期的沉积过程并导致了遗址周边微地貌的改变;在三杨庄遗址识别出了多层不同时期的人为古土壤,包括新石器晚期、战国时期、汉代和唐代;在大张龙村发现了北宋时期黄河泛滥沉积物,其沉积过程可能受周边村落遗址的影响.根据测得的14C年代和沉积层厚度,本研究进一步对这3处遗址的沉积速率进行了估算,并与前人对华北平原沉积速率的相关研究进行了对比.结果表明,这3处遗址所显示的沉积速率自3000 a B.P.开始显著增加,与对早期历史时期黄河河道沉积速率的估算结果相吻合.因此,基于遗址的地质考古研究能够为探索人与环境的互动关系提供大量信息.未来的工作中,我们需要开展更多基于考古遗址的河流地质考古研究,以深入探讨华北平原的自然沉积过程与文明演进过程之间的关系. 相似文献
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17.
P. Clifford 《Australian Journal of Earth Sciences》2019,66(6):955-972
The cliffed and active dune coastal region of Broome provides an excellent record of Pleistocene and Holocene stratigraphy of desert environments interfacing with the Indian Ocean. The Mesozoic Broome Sandstone is the basal stratigraphic unit in the area and is overlain by Pleistocene red desert quartz sand (Mowanjum Sand). Modern coastal processes of waves, wind and tide have resulted in distinctive sedimentary bodies (stratigraphic units) clearly linked to the sedimentary environment. The Mowanjum Sand, reworked by coastal winds, generates the landward-ingressing orange quartzose Churchill Sand, or reworked by waves and abraded to white sand with the addition of carbonate grains that form the beaches (Cable Beach Sand) and with eolian action, coastal dunes or inland-ingressing white dunes (Shoonta Hill Sand). These sedimentary bodies and stratigraphic units form a template with which to locate and interpret archaeological middens and Indigenous occupation over the past 5000?years in a context of coastal occupation, coastal stability, mean sea-level changes, climate changes, and availability of marine food and freshwater. Shell middens and stone artefacts form definitive layers or horizons in relation to the stratigraphy, in places in situ, and elsewhere reworked as sheets and plumes; understanding their inter-relationships has enabled the unravelling of the archaeological history and relating Indigenous occupation to biofacies and lithofacies. The array of sedimentary, biofacies and stratigraphic units are of national geoheritage significance in their own right. The addition of archaeological deposits as stratigraphic units provides a link between geoheritage and archaeology, where the archaeological materials are viewed as part of the complex stratigraphic story, part of the coastal history, and part of the geoheritage story. 相似文献
18.
以广西六景、象州大乐、桂林塘家湾及贵州独山与贵阳东北郊乌当剖面为例,在已有的地层、古生物、沉积相研究的基础上,开展了层序地层学研究.通过这项研究,认为那高岭组与莲花山组的界线是一年代地层、岩石地层及层序地层合一的界面;论证了大乐剖面应堂组的古琶段与贵州独山剖面的龙洞水组属于下泥盆统的可行性;总结了吉维特阶与艾菲尔阶间多处存在沉积间断面或沉积停滞面的客观事实,确认该界面为一符合实际又易于识别的自然界面,可作为D_2~2 /D_2~1的界面;讨论了存在于不同沉积相中的D_3/D_2界面,认为该界面置于D_2~2上部层序之上的海进体系域顶面,与以牙形类为准确立的界线很接近,但其更利于野外实际工作;对贵阳东北郊乌当剖面乌当组的归属提出疑问,并将其定为吉维特阶早期. 相似文献
19.
Z. Liu H. C. Jia J. X. Tian Y. H. Chen C. Y. Dong 《Australian Journal of Earth Sciences》2019,66(3):431-458
The Qaidam Basin is a Mesozoic–Cenozoic compresso-shearing basin in western China. This basin has been subsiding since the Indosinian orogeny, and the subsidence is a strongly inherited feature in its Quaternary development. Five third-order sequences (SQ1, SQ2, SQ3, SQ4 and SQ5) were recognised using drilling/logging, coring and seismic data analysis. Each sequence was further divided into transgressive systems tract and regressive systems tract based on the maximum flooding surface. A sequence stratigraphic framework was established that revealed the distribution of sedimentary systems. Seven depositional systems, namely, alluvial fan, fan delta, braided-delta, shore lacustrine, shallow lacustrine, semi-deep lacustrine and incised valley depositional system, were identified from 105 well logs and 2?D seismic lines covering 1600?km. The sedimentary system distribution was identified as follows: (1) large-scale alluvial deposit located on the southern slope and adjacent to Kunlun Mountain and Yaber tectonic zone located northeast of the study area; (2) braided-delta deposits southeast of the Sanhu area; (3) widely developed fan-delta sediments on the base of Qigequan Formation in the Yaber tectonic zone; (4) well-deposited shoal lacustrine facies along the depositional strike in the regressive systems tract; (5) widely distributed shallow lacustrine facies; and (6) incised valley with large lateral extension and incision depth as an entity at the front of the Golmud Basin in the Sanhu area. Two different depositional models, namely, east and west models, were built by conducting an integrated analysis of sequence stratigraphy and sedimentary process. In the Sanhu area, the main controlling factors of the sequence architecture and depositional systems associations of the Qigequan Formation are tectonic subsidence and climate change with sediment supply and lake-level fluctuation secondary factors. This case study provides an example of the analyses of sequence stratigraphy and depositional systems in a salinised plateau basin. The approach combines seismic and sedimentary facies analysis to investigate Quaternary deposition and stratigraphy. The low-amplitude tectonic belt on the northern slope and the lithological traps on the southern slope are predicted to be favourable for the lithological gas reservoirs. 相似文献
20.
ANDREW D. MIALL 《Sedimentology》1985,32(6):763-788
Eight continuous cores up to 150 m long and spaced an average of 200 m apart yield a detailed local insight into the composition and architecture of an ancient continental margin sequence, the Gowganda Formation (early Proterozoic: Huronian) near Elliot Lake, Ontario. Nearby outcrops of similar facies provide important supplementary data on sedimentary structures. Continental glaciers provided an abundant supply of coarse debris but, apart from rafting of debris by floating ice, played little or no part in Gowganda sedimentation. The basal 50 m of the Gowganda Formation in the drill-hole area represents a continental slope depositional system. It consists mainly of gravelly and sandy sediment gravity flow deposits, interbedded with minor rain-out units of diamictite, and argillite containing dropstones. Ten types of sediment gravity flow deposit are distinguished. An overlying submarine-channel depositional system, 10–50m thick, consists of hemipelagic argillites containing dropstones and showing deformation structures. These are interbedded with well-sorted channel-fill sandstones. Submarine point bars 4·5 m thick (identified in nearby outcrops) demonstrate a meandering channel geometry. This channel-fill sequence probably formed during a period of high sea-level and reduced sediment supply, but the relationship to ice advance-retreat cycles is unclear. The subsurface sequence is completed by a blanket of massive rain-out diamictites up to 55 m thick, and a younger slope sequence of sediment gravity flow diamictites and sandstones. The stratigraphy is quite different in outcrop section 10 km to the west of the drill-holes, suggesting the presence of major lateral facies changes and/or internal erosion surfaces within the Gowganda Formation. This complexity of stratigraphy and depositional processes is probably a feature of many ancient glacial units, and points to the advisability of not making climatic or tectonic interpretations from a few generalized or composite sections. 相似文献