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1.
本文从岩石的原生构造、残留结构和副矿物特征等探讨产于前寒武纪地层中的变质层状钠质岩的成因. 根据钠质岩的产出与上下岩层(正常沉积变质岩)整合和沉积过渡关系,岩石具变余层理构造、变余砂状结构,局部见交错层、韵律层,以及副矿物锆石、电气石呈浑圆状等.认为该岩石应属于沉积变质形成。而不是海底喷发的火山熔岩. 相似文献
2.
Jiang Qigang 《吉林大学学报(地球科学版)》1994,(3)
寒武－奥陶系太阳顶群是西秦岭南亚带天重要的合金－铀岩系，其主要由碳质硅质岩及碱质板岩组成，岩石中还保留了许多沉积组构，如块状构造、纹层构造、韵律构造、结核状构造等。根据岩石学、岩石组合、沉积组构，结合岩石化学、微量元素及稀土元素特征，认为太阳顶群岩石为被动大陆边缘陆缘海槽中的非补偿性沉积，形成于半深水的滞流水沉积环境。 相似文献
3.
姜琦刚 《长春地质学院学报》1994,24(3):271-277
寒武－奥陶系太阳顶群是西秦岭南亚带最重要的含金－铀岩系，其主要由碳质硅质岩及碳质板岩组成，岩石中还保留了许多沉积组构，如块状构造，纹层构造，韵律构造，结核状构造等，根据岩石学，岩石组合，沉积组构，结合岩石化学，微量元素及稀土元素特征，认为太阳顶群岩石为被动大陆边缘陆海槽中的非补偿性沉积，形成于半深水的滞流水沉积环境。 相似文献
4.
凤县八卦庙特大型金矿热水沉积岩的地质地球化学特征 总被引：6，自引：0，他引：6
八卦庙特大型金矿的成因引人注目 ,作者提出含矿地层中存在的一套条带状岩石属于热水沉积成因。此套岩石顺层产出 ,主要由富石英纹层、富钠长石 -石英纹层和富铁碳酸盐纹层互层 ,构成纹层条带构造 ,具有沉积韵律和沉积旋回 ;地层走向上 ,条带状岩石渐变过渡为千枚岩或板岩 ,显示局部凹陷的热水沉积盆地特点 ;条带岩的化学成分、微量元素特征与秦岭泥盆系铅锌矿床中的硅质 -钠质 -铁碳酸质热水沉积岩非常相似 ,具有热水沉积特点。热水沉积岩与金矿化空间关系密切 ,说明八卦庙金矿属于热水沉积 (改造 )型金矿床。矿床成因类型的正确认识有利于指导区域找矿工作。 相似文献
5.
王成文 《吉林大学学报(地球科学版)》1998,(2)
在概要地讨论了辽河岩群基本地层学特征基础上,提出了构造变质岩石地层的概念,其含义为经强烈构造变形的中浅变质沉积（含火山沉积）岩系构成的岩石地层单位的一种类型。构造变质岩石地层单位是强变形、中浅变质沉积岩区１∶５万填图的基本填图单位。建议采用岩群、岩组、岩段等地层单位命名系统,强调了变形、变质、沉积综合研究方法。 相似文献
6.
7.
层形态的概念及地质意义 总被引：1，自引：0，他引：1
层形态是作者在开发“大陆伸展盆地构造沉积模拟系统”过程中提出的一个新概念，层形态是指能够反映盆地构造沉积演化过程的沉积地层的几何形态，大陆伸展盆地的构造沉积学模拟结果表明，在不同伸展速率下形成的盆地具有不同的层形态，瞬时伸展盆地的层形态为板状，快速持续伸展盆地表现为尖楔形层形态，在这两种端元情况下存在着一系列过渡类型，通过在地震剖面和地质剖面上分析盆地的层形态和其随时间的变化，有助于对盆地构造沉积 相似文献
8.
本文所提出的确定构造运动速率的数学方法是建立在利用沉积盆地的动力学模型的基础之上的,这些模型描述了沉积盖层之间面运动的动力学特征。所需输入资料为,现在沉积层面、陆地表面和基底的位置、地层时代、每个层沉积深度的变化范围。根据地球动力学模型,古构造分析问题可简化为对构造速率的确定,这一构造速率在规定的参考时刻和假设的限制下,确定了模型的表面地形,而在最后时刻使界面与同时的 相似文献
9.
层形态是作者在开发“大陆伸展盆地构造沉积模拟系统（ＴＳＭＳ）”过程中提出的一个新概念。层形态是指能够反映盆地构造沉积演化过程的沉积地层的几何形态，大陆伸展盆地的构造沉积学模拟结果表明，在不同伸展速率下形成的盆地具有不同的层形态、瞬时伸展盆地的层形态为板状，快速持续伸展盆地表现为尖楔形层形态，在这两种端元情形下存在着一系列过渡类型，通过在地震剖面和地质剖面上分析盆地的层形态和其随时间的变化，有助于对盆地构造沉积过程的认识 相似文献
10.
大地化学背景是一种区域地球化学背景。计算深度为地壳最上部的沉积构造层。根据现有的地质学、地球物理学、地球化学和地理学资料,新疆北部地区的面积857000km2,沉积构造层平均厚度为13.9km,其质量为3.13×1016t.在沉积构造层模型和岩石化学资料基础上,计算和研究了新疆北部地区沉积构造层的平均化学成分和元素丰度。大地化学背景比地壳和岩石圈的化学背景具有更高肯定性。其背景值对区域成矿分析和矿产资源总量评价以及环境质量分析和评估等工作,具有更大的实用价值。本文给出新疆北部地区各大地构造单元的大地化学背景。 相似文献
11.
N. P. Chamov 《Lithology and Mineral Resources》2008,43(4):338-353
Interrelation of tectonic and sedimentary processes is realized at different hierarchical levels (from a common geodynamic setting of sedimentary basin to the behavior of its local structures) and at different stages of basin evolution (from sedimentation to rock formation). Based on several examples, the paper considers issues related to the reflection of tectonic processes in sedimentary sequence, the development of complex tectonosedimentation models of sedimentary basins, the identification of mineralogical-petrographical and petrochemical indicators of tectonic settings, as well as the study of mutual influence of tectonic and lithogenetic factors on the rock formation in the basins. 相似文献
12.
云南楚雄盆地位于场子陆块的西南边缘,为一典型的中生代周缘前陆盆地,盆地演化阶段明显,晚三叠世为前陆早期复理石沉积,侏罗纪则为前陆晚期磨拉石沉积。对盆地构造沉降史研究后笔者认为：①晚三叠世复理石沉积盆地构造沉降幅度巨大,沉降与沉积中心位于盆地最西部,紧邻古哀牢山造山带,沉积体呈形楔形展布;③侏罗纪磨拉石沉积盆地构造沉降和沉积中心以及前缘隆起向内陆方向迁移明显;③中生代构造快速沉降的沉积体的楔形展布表 相似文献
13.
Zhenglong Jiang Shu Jiang Xiaodong Lan Buqing Wang Shaoying Huang He Zhang 《International Geology Review》2018,60(10):1213-1230
The Tarim Basin Craton is located in the center of the Tarim Basin. Since the beginning of the Miocene, the tectonic activity has been weaker in the Tarim Basin Craton than in the marginal depression and the peripheral orogenic belts. This study investigates the tectonic movements in the Tarim Basin Craton by calculating the sedimentation rates and constructing balanced cross-sections based on well, seismic and geologic data. The tectonic movements in the Tarim Basin Craton have mainly been revealed by geological processes such as sedimentation and subsidence, structural inversion, changes in the structural feature, migration of the structural highs, and faulting. The Neogene sedimentary strata were mainly deposited in two sedimentation centers, the southern and northern sedimentation centers, and the strata in the Central Uplift Zone are relatively thin. The different depressions in different geological periods experienced wide variations in tectonic activity. Tectonic subsidence was significant and the sedimentation rates were high in the Tarim Basin Craton during the Pliocene Period (phase II). During the Neotectonic period, the stresses in the South-North direction converged in the Central Uplift Zone (the Bachu uplift–Central Tarim uplift), and the tectonic activity in this region was more intense than that in the Northern Depression and the Maigaiti Slope in the southwest. In addition, the scale of the paleo-uplift, including paleo-North Tarim Uplift and paleo-Central Uplift Zone, gradually decreased. The faults and fault systems developed zonationally in Neotectonic formations in different structural units, and always distributed discontinuously in vertical direction in sections. 相似文献
14.
N. G. Vashchenkova M. T. Gorovaya A. V. Mozherovskii I. B. Tsoy 《Stratigraphy and Geological Correlation》2011,19(6):663-678
A complex (petrographic, micropaleontological, and X-ray diffraction) investigation of the sedimentary cover on the northwestern
slope of the Okushiri Ridge in the Sea of Japan revealed that its basal layers are of Oligocene age and composed of terrigenous
silty-clayey sediments, which were deposited in coastalmarine environments with calm hydrodynamics and low sedimentation rates.
The relative sea-level rise combined with regional tectonic processes at the early-middle Miocene transition resulted in widening
and deepening of sea basins and accumulation of a thick diatomaceous-clayey sequence of middle-upper Miocene sediments. Tectonic
activation in the Pliocene was responsible for development of the ridge and exhumation of rocks formerly occurring at depth
of 500–1000 m. 相似文献
15.
西藏羌北—昌都地区三叠纪岩石地层及印支运动 总被引：1，自引：0，他引：1
西藏羌北—昌都地区地处阿尔卑斯—喜马拉雅构造域东段弧形转弯部分,位于“劳亚大陆”与“冈瓦纳大陆”之间,是一个具有过渡性质的中间陆块,即常被称为“三江褶皱系”。羌北—昌都地区属于“褶皱系”的北段,其岩石地层、生物地层、岩浆活动、火山作用、构造运动、地壳变形变质作用等方面都具有独立的特征,但与周围也具有诸多的联系。从现代地层学、沉积学的观点研究认为,羌塘—昌都地区的印支运动主要受到３个区域性构造运动界面的控制,形成两个主要的构造层,属于印支运动的主幕有两期。印支期的海水进退、岩石地层沉积、岩浆火山活动、变形变质作用与成矿作用等都可分属这两期构造运动的产物。 相似文献
16.
Wilfried Winkler 《Geodinamica Acta》2013,26(2):81-102
AbstractDeep-sea turbidite sedimentation in convergent margin settings generally is controlled by tectonic uplift, climate and eustatic sea-level variations. The rate of tectonic uplift governs the relief of the source area and the position of the base level (coinciding with sea-level), climate influences the rate and style of weathering and continental runoff and eustatic seal-level additionally shifts the base level, functioning with the concurrently working tectonic movements. Thus, these factors primarly determine the availability of sediment (yield and nature of material and the site of intermittent storage) at the basin margin which is unlocked periodically to flow downslope to the basin.This paper attempts to decipher quantitatively the importance of the individual factors in the Late Maastrichtian to Early Eocene Schieren Flysch Croup. The flysch was deposited in a moderately converging remnant oceanic trench basin. Mean parameters are calculated on the basis of formations and the duration of nannofossil zones comprised in. For transposing these zone into absolute age intervals the problem of inconsistent durations in current time scales had to be solved by a best-fit approach. Frequencies and periodicities of turbidite events, decompacted and compacted sedimentation rates (the latter are considered as apparent denudation rates) are calculated to reveal the dynamics of sedimentation. Climatic evidence is deduced from clay mineralogy. Changing uplift rates in the drainage area are indirectly interpreted from back-stripped tectonic subsisdence rates in the basin.The obtained data point to an immediate control of sub-duction-Iinked tectonic uplift in the bordering drainage and shelf area on turbidite sedimentation, as frequency and thickness of the turbidite events are closely correlated with the increasing tectonic subsisdence in the basin (assumed to match the rate of subduction and underplating). This general trend is modified by the temporary migration of the oceanic hinge zone towards the trench causing periodically the starvation of outer portions of the basin at the transition from Early to Late Paleocene and Late Paleocene to Eocene. Regional climatic trends additionnaly rule the turbidite facies development and apparent denudation rates. In the upper part of Early Eocene series high rate mud dominated sediments correlate with warm/humid conditions and in Late Paleocene deposits low rate sandy sediments coincide with cool ones. During the Late Paleocene period the global 2nd-order sea-level lowering probably may be responsible for the by-passing of the shelf by the coarse grained sediments. 相似文献
17.
震旦系灯影组白云岩多级次岩溶储层叠合发育特征及机制 总被引：1，自引：0，他引：1
受加里东早期桐湾运动一幕和二幕强烈构造抬升运动影响,震旦系灯影组二段和四段白云岩顶部分别遭受了强烈长期区域性不整合面岩溶作用。除顶部不整合面岩溶之外,灯影组二段和四段白云岩层内部也都见有多个具有层状特征的短期岩溶发育段,与灯影组二段和灯影组四段沉积过程中多个短期构造抬升沉降旋回有关,在四级层序界面下发育。在短期构造抬升事件影响下,相对海平面下降,白云岩暴露地表,发生同生/准同生期短期层内岩溶作用;形成多个几米至十几米厚的白云岩层内岩溶孔洞发育段;岩溶孔洞发育段之间为短期构造沉降期间较深水环境下沉积形成的致密泥晶白云岩、泥质白云岩或硅质白云岩层。四川盆地北部南江县映水坝剖面灯影组二段和四段分别识别出4层和8层层内短期岩溶发育段;川中乐山-龙女寺隆起钻井对比在灯影组二段白云岩中识别出6层层内短期岩溶发育段。白云岩层内的多个同生/准同生期短期岩溶发育段在垂向上的叠加形成了现今灯影组具有较大厚度的白云岩储层。桐湾一幕和二幕长期不整合面岩溶作用使灯影组二段或四段内部的短期岩溶层储集性能进一步改善。 相似文献
18.
V. V. Ivanova A. A. Shchetnikov I. A. Filinov S. V. Veshcheva A. Yu. Kazansky G. G. Matasova 《Lithology and Mineral Resources》2016,51(3):179-194
The results of study of rocks of the Ust-Oda section, one of the key outcrops of Upper Neopleistocene sediments in the Irkutsk Amphitheater of the Siberian Platform, are presented. It is shown that primary sediments were deposited in the Neopleistocene under subarid conditions and relatively high sedimentation rates. Similar contents of trace elements in all rock lithologies suggest that the provenance was unaltered during sedimentation. It is shown that variation in the sediment transport mechanism is one of the signs of changes in the paleoclimatic setting. Climatic cyclicity of the Ust-Oda section formation and succession of sedimentation setting, which were reconstructed on the basis of grain size data, correspond to variations in the petrochemical correlations and geochemical coefficients. 相似文献
19.
《Sedimentary Geology》2002,146(1-2):11-24
Sedimentation coeval with growth of the Santaren anticline provides an excellent opportunity to study the relationships between sedimentation and anticline uplift through time. The Santaren anticline is a kilometre-scale, NW–SE trending fold offshore of Cuba, in the Bahamas foreland of the Cuban fold and thrust belt. The growth strata associated with this anticline consist of a thick package of carbonate sediments that were deposited without major interruptions from Neogene (and perhaps before) to present day.The excellent seismic resolution and age control of a number of seismic horizons within the growth strata allowed us to define 25 growth beds, each of them representing between 0.1 and 3.2 Ma. An analysis of the thickness of these beds allowed us to determine accurate quantitative values of cumulative decompacted thickness and crestal structural relief at the time of their deposition. In addition, for the same periods, sedimentation and fold uplift rates were calculated. Moreover, some information on relationships between sedimentation and fold uplift rates was inferred from the growth stratal geometry. Growth beds that overlap the fold crest and thin over it indicate that sedimentation rates outpaced fold growth rates during their deposition. Some overlapping beds have constant thickness indicating that no fold uplift occurred during their sedimentation. The rest of the growth beds exhibit onlap/offlap geometries that do not indicate a unique sedimentation/fold uplift rate relationship. Only in those cases in which the geometry of the underlying bed at the end of its deposition is known is it possible to infer a specific sedimentation/fold uplift rate relationship.As a result of this analysis, we have been able to (1) illustrate that the geometry of the growth strata associated with the Santaren anticline results from competition between sedimentation and tectonic fold uplift, (2) document the episodic and non-steady nature of fold growth, and (3) show that short-term rates (at the scale of hundreds of thousands years) provide much insight into the interplay between sedimentation and tectonic fold uplift that control the growth stratal patterns. 相似文献
20.
Valentine O. Mikhailov 《Mathematical Geology》1993,25(7):949-961
The method to determine the rates of tectonic movements is based on the use of dynamic models of sedimentary basins. A standard dataset should be provided as input information: the present-day position of sedimentary layer interfaces (chronostratigraphic boundaries), land surface and basement, the layer ages, and the uncertainty limits within which the depth of sedimentation of each layer may have differed. In terms of dynamic models, the paleotectonic analysis problem is reduced to the determination of such tectonic rates that, at prescribed reference times, the model surface topography within the assumed limits would be constrained. At the final moment, the interfaces would be brought into agreement with the contemporary geologic cross-section. The analysis the problem of tectonic rates determination has shown that it has no unique solution. One of the ways to obtain the unique solution is to seek it within a prescribed class of functions, for example, the Fourier series. This method differs from the paleotectonic analysis methodology in that it treats the tectonic rates of motion as functions of time and spatial variables. Under certain conditions, it proves feasible to reconstruct the rates of tectonic movements not only within the time intervals represented in the deposited strata, but within periods of erosion as well. It also is possible to take into account the deformation-induced changes in thickness of the layers. The method's application is illustrated with an example of the Terek-Caspian Trough. As follows from the computation, the tectonic movements since the Middle Jurassic may be presented as a sum of two components: an overall slowing-down subsidence whose rate is proportional to the square root of the age, and local movements which follow a regular oscillatory time pattern with a period of 60–70 MY. The character of the local movements is such that the profile appears to break into a northern and southern segment. When one was being uplifted, the other segment was sinking, andvice versa. These two segments are separated by a deep-seated fault. This may have been a result of an external compression on the trough. 相似文献