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Cyclic Sequences, Events and Evolution of the Sino-Korean Plate, with a Discussion on the Evolution of Molar-tooth Carbonates, Phosphorites and Source Rocks 被引量:17
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作者 MENG Xianghua and GE MingInstitute of Sedimentary Basin, China University of Geosciences, Beijing 100083 E-mail: mengxh@cugb.edu.cn Liu Xinzhu and Zhu Xiling 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第3期382-401,共20页
This paper gives an account of the research that the authors conducted on the cyclic sequences, events and evolutionary history from Proterozoic to Meso-Cenozoic in the Sino-Korean plate based on the principle of the ... This paper gives an account of the research that the authors conducted on the cyclic sequences, events and evolutionary history from Proterozoic to Meso-Cenozoic in the Sino-Korean plate based on the principle of the Cosmos-Earth System. The authors divided this plate into 20 super-cyclic or super-mega-cyclic periods and more than 100 Oort periods. The research focused on important sea flooding events, uplift interruption events, tilting movement events, molar-tooth carbonate events, thermal events, polarity reversal events, karst events, volcanic explosion events and storm events, as well as types of resource areas and paleotectonic evolution. By means of the isochronous theory of the Cosmos-Earth System periodicity and based on long-excentricity and periodicity, the authors elaborately studied the paleogeographic evolution of the aulacogen of the Sino-Korean plate, the oolitic beach platform formation, the development of foreland basin and continental rift valley basin, and reconstructed the evolution 展开更多
关键词 Cosmos-Earth system periodicity cyclic sequence geological event Sino-Korean plate
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Genetic Types of Meter-Scale Cyclic Sequences and Fabric Natures of Facies Succession 被引量:16
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作者 Mei Mingxiang Xu Debin Zhou Hongrui Institute of Earth Sciences and Natural Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 2000年第4期3-10,共8页
Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result f... Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result from the sedimentation governed by different sediment sources and sedimentary dynamic conditions in different paleogeographical backgrounds, corresponding to high-frequency sea-level changes. Naturally, this is the fundamental criterion for the classification of genetic types of meter-scale cyclic sequences. The widespread development in stratigraphic records and the regular vertical stacking patterns in long-term sequences, the evolution characters of earth history and the genetic types reflected by specific fabric natures of facies successions in different paleogeographical settings, all that show meter-scale cyclic sequences are not only the elementary working units in stratigraphy and sedimentology, but also the replenishment and extension of parasequence of sequence stratigraphy. Two genetic kinds of facies succession for meter-scale cyclic sequence in neritic-facies strata of carbonate and clastic rocks, are normal grading succession mainly formed by tidal sedimentation and inverse grading succession chiefly made by wave sedimentation, and both of them constitute generally shallowing upward succession, the thickness of which ranges from several tens of centimeters to several meters. The classification of genetic types of meter-scale cyclic sequence could be made in terms of the fabric natures of facies succession, and carbonate meter-scale cyclic sequences could be divided into four types: L-M type, deep-water asymmetrical type, subtidal type and peritidal type. Clastic meter-scale cyclic sequences could be grouped into two types: tidal-dynamic type and wave-dynamic type. The boundaries of meter-scale cyclic sequences are marked by instantaneous punctuated surface formed by non-deposition resulting from high-frequency level changes, which include instantaneous exposed punctuated surface, drowned punctuated surface as well as their relative surface. The development of instantaneous punctuated surface used as the boundary of meter-scale cyclic sequence brings about the limitations of Walter's Law on the explanation of facies distribution in time and space, and reaffirm the importance of Sander's Rule on analysis of stratigraphic records. These non-continuous surface could be traced for long distance and some could be correlative within same basin range. The study of meter-scale cyclic sequences and their regularly vertical stacking patterns in long-term sequences indicate that the research into cyclicity of stratigraphic records is a useful way to get more regularity from stratigraphic records that are frequently complex as well as non-integrated. 展开更多
关键词 genetic types fabric natures of facies succession meter-scale cyclic sequences.
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Almost perfect sequences based on cyclic difference sets 被引量:6
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作者 Chen Gang Zhao Zhengyu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期155-159,共5页
The perfect sequences are so ideal that all out-of-phase autocorrelation coefficients are zero, and if the sequences are used as the coding modulating signal for the phase-modulated radar, there will be no interferenc... The perfect sequences are so ideal that all out-of-phase autocorrelation coefficients are zero, and if the sequences are used as the coding modulating signal for the phase-modulated radar, there will be no interference of side lobes theoretically. However, it has been proved that there are no binary perfect sequences of period 4 〈 n ≤ 12100. Hence, the almost perfect sequences with all out-of-phase autocorrelation coefficients as zero except one are of great practice in engineering. Currently, the cyclic difference set is one of most effective tools to analyze the binary sequences with perfect periodic autocorrelation function. In this article, two characteristic formulas corresponding to the autocorrelation and symmetric structure of almost perfect sequences are calculated respectively. All almost perfect sequences with period n, which is a multiple of 4, can be figured out by the two formulas. Several almost perfect sequences with different periods have been hunted by the program based on the two formulas and then applied to the simulation program and practical application for ionospheric sounding. 展开更多
关键词 Perfect sequence Almost perfect sequence cyclic difference sets Autocorrelation coefficients Side lobes Ionospheric sounding
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GAUSS PERIODS AND CYCLIC CODES FROM CYCLOTOMIC SEQUENCES OF SMALL ORDERS 被引量:1
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作者 Hu Liqin Yue Qin Zhu Xiaomeng 《Journal of Electronics(China)》 2014年第6期537-546,共10页
Let p =ef +1 be an odd prime with positive integers e and f. In this paper, we calculate the values of Gauss periods of order e =3, 4, 6 over a finite field GF(q), where q is a prime with q≠p. As applications, severa... Let p =ef +1 be an odd prime with positive integers e and f. In this paper, we calculate the values of Gauss periods of order e =3, 4, 6 over a finite field GF(q), where q is a prime with q≠p. As applications, several cyclotomic sequences of order e =3, 4, 6 are employed to construct a number of classes of cyclic codes over GF(q) with prime length. Under certain conditions, the linear complexity and reciprocal minimal polynomials of cyclotomic sequences are calculated, and the lower bounds on the minimum distances of these cyclic codes are obtained. 展开更多
关键词 sequence cyclic code Weight distribution Gauss period CYCLOTOMY
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Base-level Chang and Sequence Stratigraphy of Lishu Fault Lacustrine Basin
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作者 Wang Simin Liu Zhaojun Liu Kui 《Global Geology》 2000年第1期70-76,共7页
Base-level is a kind of surface which controls sedimentation and erosion. So, it can be concluded that it is base-level change that controls the formation and internal structure of a sequence. A single cycle of base-l... Base-level is a kind of surface which controls sedimentation and erosion. So, it can be concluded that it is base-level change that controls the formation and internal structure of a sequence. A single cycle of base-level change can generate four sets of different stacking patterns. They are two sets of aggradation, one progradation and one retrogradation, which affects the features of the internal structure of a sequence. Lishu fault subsidence of Songliao basin is a typical half-graben lacustrine basin. Comprehensive base-level change analysis indicates that six base-level cycles and their related six sequences can be recognized between T 4 and T 5 seismic reflection surface. The contemporaneous fault is the main controlling factor of the fault lacustrine basin. There are obvious differences exist in the composition of sedimentary systems and all systems tracts between its steep slope (the side that basin control fault existed) and flat slope. Except highstand systems tract is composed of fan delta-lacustrine system, lowstand systems tract, transgressive systems tract and regressive systems tract are all made up of fan delta-underwater fan-lacustrine sedimentary systems in the side of steep slope. 展开更多
关键词 base-level FAULT LACUSTRINE basin sequence STRATIGRAPHY sequence STRATIGRAPHIC model Songliao bas
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On the analysis of the high-resolution sequence stratigraphy and coal accumulating law of jurassic in Ordos Basin 被引量:8
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作者 李增学 韩美莲 +3 位作者 李江涛 余继峰 吕大炜 柳汉丰 《Journal of Coal Science & Engineering(China)》 2008年第1期85-91,共7页
The strata of Jurassic was divided into three tectonic sequences and eight se- quences of third rank,according to the developing feature of the tectonic inconformity and the transforming feature of the depositional sy... The strata of Jurassic was divided into three tectonic sequences and eight se- quences of third rank,according to the developing feature of the tectonic inconformity and the transforming feature of the depositional system tracts.Also the identification and the division of the base-level cycle of different period were carried through.Therefore three cycles of super period,eight cycles of long period,twenty-four cycles of middle period and some cycles of short period were identified.From the overall character of the coal-accu- mulation in the Mesozoic,we can see that the Yan'an formation is of the best nature of coal bearing.When the coal bearing systems of Jurassic were depositing,the Ordos area is the coal accumulating basin of terrene of large scale and located in the same tectonic unit.But the local structure of different part and the paleolandform are different in the basin which resulted in the difference of the depositional environment.So the layer number and the distribution of the thickness of the coal beds are different in the different part of the ba- sin.The coal-accumulating action migrated regularly along with the development,evolve- ment and migration of the depositional systems.The layer numbers of the coal beds, which can be mined,are more in the north and west fringe of the basin,whose distributing area is extensive,and they are more steady in the landscape orientation,also the total thickness is great.Therefore the nature of coal bearing and the coal-accumulating action of different part changed obviously in the space in Ordos area. 展开更多
关键词 high resolution sequence stratigraphy base-level cycle coal accumulating law the migration of rich-coal units
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Selection and application of wavelet transform in high-frequency sequence stratigraphy analysis of coarse-grained sediment in rift basin 被引量:1
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作者 Ling Li Zhi-Zhang Wang +4 位作者 Shun-De Yin Wei-Fang Wang Zhi-Chao Yu Wen-Tian Fan Zhi-Heng Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3016-3028,共13页
Wavelet transformation is a widely used method in high-frequency sequence stratigraphic analysis.However, the application is problematic since different wavelets always return the same sequence analysis results. To ad... Wavelet transformation is a widely used method in high-frequency sequence stratigraphic analysis.However, the application is problematic since different wavelets always return the same sequence analysis results. To address this issue, we applied five commonly used wavelets to theoretical sequence models to document some application criteria. Five gradual scale-change sequence models were simplified from the glutenite succession deposition by gravity flows to form the fining-upwards cycle sequences(FUCS) and coarsening-upwards cycle sequences(CUCS). After conducting theoretical sequence model tests, the optimal wavelet(sym4) was selected and successfully used with actual data to identify the sequence boundaries. We also proposed a new method to optimize the scale of continuous wavelet transformation(CWT) for sequence boundary determination. We found that the balloon-like marks in scalograms of db4, sym4, and coif4 wavelet determine, respectively, the fourth-order sequence boundary, the thick succession sequence boundaries in FUCS, and the thick succession sequence in FUCS and CUCS. Comparing the sequence identification results shows that the asymmetric wavelets had an advantage in high-frequency sequence boundary determination and sedimentary cycle discrimination through the amplitude trend of the coefficient, in which the sym4 wavelet is the most effective. In conclusion, the asymmetry of wavelets is the first selection principle, of which asymmetric wavelets are more sensitive to sediment deposition by flood flows. The match of the wavelet between the sequence is the second selection principle, in which the correlation of time-frequency impacts the accuracy of sequence surface localization. However, the waveform of the wavelet is a visual and abstract parameter for sequence boundary detection. The appropriate wavelet for lacustrine sequence analysis is the asymmetric wavelet with a weak number of side lobes. The depositional flows, depositional process,and autogenic are three sedimentary factors that influence the sequence analysis results. 展开更多
关键词 Wavelet analysis High-resolution sequence Sedimentary cyclicity Asymmetric wavelets
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HIGH-RESOLUTION SEQUENCE STRATIGRAPHIC ANALYSIS OF THE PERMIAN IN THE WESTERN SHANDONG AND HUAINAN-HUAIBEI COALFIELDS 被引量:1
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作者 李增学 魏久传 韩美莲 《Journal of Coal Science & Engineering(China)》 1999年第1期1-10,共10页
The sedimentary characteristics and their combination succession of the Permian in the Shandong nd Huainan-Huaibei coalfields are analyzed. The mid-and short-term stratigraphic base-level cycles are identified. High-r... The sedimentary characteristics and their combination succession of the Permian in the Shandong nd Huainan-Huaibei coalfields are analyzed. The mid-and short-term stratigraphic base-level cycles are identified. High-resolution sequences are divided based on the above results. The study shows that the stratigraphic base-level cyclic method is an efficient way in the determination of the high-resolution sequences, especially in the classification of tbe terrestrial and transitional depositional succession. 展开更多
关键词 PERMIAN stratigraphic base-level cycles high-resolution sequence stratigraphic analysis western Shandong coalfields Huainan-Huaibei coalfields
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Sequence Stratigraphic Features of Mesozoic-Cenozoic Nonmarine Sediments in Eastern China
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作者 Xu Huaida Wei Kuisheng (Departrment of Energy Resources Geology, China University of Geosciences, Beijing 100083) 《Journal of Earth Science》 SCIE CAS CSCD 1994年第1期55-64,共10页
The basic concepts of sequence stratigraphy can be applied to any cyclic successions regardless of their origin being marias or nonmarine .The storm base can be taken as the base level at the gentle slope side of a f... The basic concepts of sequence stratigraphy can be applied to any cyclic successions regardless of their origin being marias or nonmarine .The storm base can be taken as the base level at the gentle slope side of a faulted basin for distinguishing the systems tractS as no shelf edge is present in nonmarihe fault6d basins. Most of coatinuous rethetions with high amplitude in seismic sections, misunderstood previously as the boundaries of stratigraphic unit, are maximum flooding surface (MFS)in fact. Abundant and diversified microfossils and nannofossils high content of organic carbon,various authigenic minerals such as glauconie,siderite are concentrated nearby these surfaces. It means that the open sea water invaded iato the faulted basins many times in Cretaceous and Paleogene, which make a restricted environment favourable for oil generation. The trend of lake level changes is similar to that of Haq's curve generally, however, the influence of local movements and autostrahgraphic events have to be colandered. The stratal patterns and models of nonmarine sequence are proposed. 展开更多
关键词 nonmarine depositional sequence sequence boundary condensed section systems tract model base-level change curve basin floor fan Eastern china.
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一种基于Hoey序列的8环QC-LDPC码构造方法
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作者 袁建国 宋万闯 《电讯技术》 北大核心 2025年第5期793-799,共7页
针对准循环低密度奇偶校验(Quasi-Cyclic Low-Density Parity-Check,QC-LDPC)码存在短环及纠错性能不好的问题,基于Hoey序列(Hoey Sequence,HS)提出了一种新颖的QC-LDPC码构造方法。该方法从HS中选取一些元素,组成呈递增趋势的集合,进... 针对准循环低密度奇偶校验(Quasi-Cyclic Low-Density Parity-Check,QC-LDPC)码存在短环及纠错性能不好的问题,基于Hoey序列(Hoey Sequence,HS)提出了一种新颖的QC-LDPC码构造方法。该方法从HS中选取一些元素,组成呈递增趋势的集合,进行简单的四则运算构造出指数矩阵,扩展得到围长至少为8的奇偶校验矩阵,并且可通过改变选取HS元素的数量进而灵活地改变码率和码长。仿真结果表明,同等条件下,在误码率为10^(-6)时,该方法所构造的码率为0.5的HS-QC-LDPC(1200,600)码与对比的几种码型相比,其净编码增益至少有0.12 dB的提升;在误码率为10^(-7)时,该方法所构造的码率为0.67的HS-QC-LDPC(3600,2400)码与对比的几种码型相比,其净编码增益至少有0.06 dB的提升。此外,所构造的校验矩阵的复杂度与指数矩阵的行列数乘积呈线性关系,与其他对比文献相比具有较低复杂度。 展开更多
关键词 准循环低密度奇偶校验(QC-LDPC)码 构造方法 Hoey序列 低复杂度
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基于Fibonacci-Lucas序列的8环QC-LDPC码新颖构造方法
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作者 袁建国 伏博文 +1 位作者 杨婷 胡坤 《半导体光电》 北大核心 2025年第3期543-549,共7页
针对当前准循环低密度奇偶校验(Quasi-Cyclic Low-Density Parity-Check,QCLDPC)码存在短环结构并且其纠错性能差的问题,文章基于斐波那契-卢卡斯序列(FibonacciLucas Sequence,FLS)提出一种围长至少为8的QC-LDPC码新颖构造方法。该方... 针对当前准循环低密度奇偶校验(Quasi-Cyclic Low-Density Parity-Check,QCLDPC)码存在短环结构并且其纠错性能差的问题,文章基于斐波那契-卢卡斯序列(FibonacciLucas Sequence,FLS)提出一种围长至少为8的QC-LDPC码新颖构造方法。该方法首先利用Fibonacci-Lucas序列构成一个满足无4环条件的指数矩阵,再利用搜索算法搜索出让该指数矩阵满足无6环条件的元素得到一个递增序列,构造相应的指数矩阵,得到其奇偶校验矩阵。仿真结果表明,当误码率为1×10^(-6)时,所构造的FLS-QC-LDPC码相较于其他三种具有相同码率和码长的QC-LDPC码,其净编码增益得到了明显改善,表现出较好的纠错性能。此外,该构造方法灵活多变,支持多种码长和码率选择,同时保持较低的计算复杂度,高效且适应性强。 展开更多
关键词 准循环低密度奇偶校验码 Fibonacci-Lucas序列 搜索算法 净编码增益
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Linear recurring sequences and subfield subcodes of cyclic codes 被引量:2
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作者 GAO ZhiHan FU FangWei 《Science China Mathematics》 SCIE 2013年第7期1413-1420,共8页
Linear recurring sequences over finite fields play an important role in coding theory and cryptography. It is known that subfield subcodes of linear codes yield some good codes. In this paper, we study linear recurrin... Linear recurring sequences over finite fields play an important role in coding theory and cryptography. It is known that subfield subcodes of linear codes yield some good codes. In this paper, we study linear recurring sequences and subfield subcodes. Let Mqm(f(x)) denote the set of all linear recurring sequences over Fqm with characteristic polynomial f(x) over Fqm . Denote the restriction of Mqm(f(x)) to sequences over Fq and the set after applying trace function to each sequence in Mqm(f(x)) by Mqm(f(x)) | Fq and Tr( Mqm(f(x))), respectively. It is shown that these two sets are both complete sets of linear recurring sequences over Fq with some characteristic polynomials over Fq. In this paper, we firstly determine the characteristic polynomials for these two sets. Then, using these results, we determine the generator polynomials of subfield subcodes and trace codes of cyclic codes over Fqm . 展开更多
关键词 linear recurring sequences characteristic polynomial cyclic codes subfield subcodes trace codes
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濮城油田沙三上地层基准面旋回及储层流动单元 被引量:14
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作者 曾大乾 李中超 +2 位作者 宋国英 汤军 张昌民 《石油学报》 EI CAS CSCD 北大核心 2002年第3期39-42,共4页
根据基准面旋回和可容纳空间变化原理 ,研究了东濮凹陷濮城油田沙三上亚段长期、中期、短期基准面旋回 ,划分出长期基准面旋回 1个、中期基准面旋回 10个、短期基准面旋回 5 0个 ,并对三种类型的短期基准面旋回结构特征及分布进行了详... 根据基准面旋回和可容纳空间变化原理 ,研究了东濮凹陷濮城油田沙三上亚段长期、中期、短期基准面旋回 ,划分出长期基准面旋回 1个、中期基准面旋回 10个、短期基准面旋回 5 0个 ,并对三种类型的短期基准面旋回结构特征及分布进行了详细描述。在高分辨率层序地层划分对比的基础上 ,建立了高精度层序地层格架。利用储层非均质性的层次性及流动单元层次性与基准面旋回级次性的相关性 ,对储层流动单元进行了划分 ,为精细储层研究提供了一种新的思路。 展开更多
关键词 濮城油田 沙三上地层 基准面旋回 储层流动单元 层序地层格架 沙三段
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环脂肽氨基酸顺序的质谱测定 被引量:19
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作者 杨世忠 牟伯中 +1 位作者 吕应年 陈涛 《化学学报》 SCIE CAS CSCD 北大核心 2004年第21期2200-2204,共5页
从一株枯草芽孢杆菌的培养液中分离得到一种生物表面活性剂,红外光谱、茚三酮显色及质谱分析表明它是一种具有环状结构的脂肽.质谱显示脂肽的脂肪酸部分为β羟基脂肪酸;氨基酸分析表明肽部分由4个亮氨酸、1个天门东氨酸、1个缬氨酸和1... 从一株枯草芽孢杆菌的培养液中分离得到一种生物表面活性剂,红外光谱、茚三酮显色及质谱分析表明它是一种具有环状结构的脂肽.质谱显示脂肽的脂肪酸部分为β羟基脂肪酸;氨基酸分析表明肽部分由4个亮氨酸、1个天门东氨酸、1个缬氨酸和1个谷氨酸组成.利用串联飞行时间质谱测定了环脂肽的分子量及质谱图.根据分子量的氮规则和质谱碎片产生的简单断裂、双氢转移机制、McLafferty等单氢重排机制,直接确定了未水解的环脂肽中脂肪链的长度以及氨基酸连接的顺序.质谱中的峰可以得到合理解释.确定了该环脂肽的环状结构. 展开更多
关键词 生物表面活性剂 脂肽 环状结构 质谱 氨基酸顺序 谷氨酸 缬氨酸 枯草芽孢杆菌 结构
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米级旋回层序的成因类型及其相序组构特征 被引量:98
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作者 梅冥相 徐德斌 周洪瑞 《沉积学报》 CAS CSCD 北大核心 2000年第1期43-49,共7页
与米兰柯维奇旋回存在成因联系的幕式地层堆积作用的结果 ,是在地层记录中形成各种类型的米级旋回层序。在不同的古地理背景中 ,受物质来源及沉积动力学背景的控制 ,故发育具有不同相序组构的不同类型的米级旋回层序。因此 ,相序组构特... 与米兰柯维奇旋回存在成因联系的幕式地层堆积作用的结果 ,是在地层记录中形成各种类型的米级旋回层序。在不同的古地理背景中 ,受物质来源及沉积动力学背景的控制 ,故发育具有不同相序组构的不同类型的米级旋回层序。因此 ,相序组构特征就成为米级旋回层序类型划分的基本准则。地层记录中米级旋回层序的广泛发育 ,以及它们在长周期层序中的有序垂直叠加形式和地史演化特征 ,由不同相序组构所反映的成因类型以及由不同类型所指示的沉积动力背景等等 ,不但表明了米级旋回层序是描述地层结构的基本工作单元 ,而且是对“准层序”的延展和补充。在海相地层中 ,不管是碳酸盐岩还是陆源碎屑岩地层 ,这种厚几厘米至几米的米级旋回层序 ,大致都可以划分为正粒序和反粒序两种相序组构 ,正粒序组构主要是潮汐作用的结果 ,而反粒序主要是以波浪作用为主的浅海环境的产物 ;不管是正粒序还是反粒序序列 ,均构成总体向上变浅序列。由此 ,碳酸盐岩米级旋回层序可划分为L—M型、深水非对称型、潮下型及环潮坪型 ;碎屑岩米级旋回层序可划分为潮汐动力型及波浪动力型。米级旋回层序的界面是由高频率海平面变化所产生的非沉积作用面 ,包括瞬时暴露间断面和瞬时加深淹没间断面乃至它们的相关面 ,这些在区域上延伸较远 ,甚至? 展开更多
关键词 成因类型 相序组构 米级旋回层序 地层 古地理
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塔里木盆地巴楚地区石炭系高频旋回层序分析 被引量:8
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作者 陈国俊 薛莲花 +2 位作者 王琪 肖立新 史基安 《沉积学报》 CAS CSCD 北大核心 1998年第4期37-41,共5页
高频旋回层序是海平面高频振荡的结果和产物。通过对塔里木盆地巴楚地区石炭系地面、钻井剖面的详细解析,首次总结出7个高频旋回层序类型,识别出50余个五级(或六级)高频旋回层序,它们在纵向上有规律地组合、叠加,组成8个四级... 高频旋回层序是海平面高频振荡的结果和产物。通过对塔里木盆地巴楚地区石炭系地面、钻井剖面的详细解析,首次总结出7个高频旋回层序类型,识别出50余个五级(或六级)高频旋回层序,它们在纵向上有规律地组合、叠加,组成8个四级旋回层序,3个三级旋回层序及2个二级旋回层序,构成了塔里木盆地巴楚地区石炭系的层序地层格架,同时也反映了该区石炭纪海平面的变化规律及其沉积响应。 展开更多
关键词 旋回层序 海平面变化 石炭纪 巴楚地区 盆地
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四川盆地须家河组层序地层格架及沉积体系分布规律探讨 被引量:34
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作者 叶泰然 李书兵 +1 位作者 吕正祥 柯光明 《天然气工业》 EI CAS CSCD 北大核心 2011年第9期51-57,135-136,共7页
不同学者针对四川盆地上三叠统地层特征及沉积演化规律从不同角度进行了诸多研究,但各自获得的地质认识却存在一定的差异。为此,在地表露头和钻测井资料分析、地震层序分析的基础上,将四川盆地须家河组划分为2个超长期基准面旋回层序,... 不同学者针对四川盆地上三叠统地层特征及沉积演化规律从不同角度进行了诸多研究,但各自获得的地质认识却存在一定的差异。为此,在地表露头和钻测井资料分析、地震层序分析的基础上,将四川盆地须家河组划分为2个超长期基准面旋回层序,为须上盆、须下盆2大成盆期的沉积响应;盆地周缘造山旋回变化是控制2大成盆期砂体分布的主导因素,纵向上总体具阶梯状分布特征,由坳陷中心向周边逐层超覆并阶梯状退积。须家河组主要为陆相河湖三角洲沉积体系,主要发育冲积扇—冲积平原—曲流河或辫状河三角洲—湖泊和冲积扇—扇三角洲—湖泊沉积体系模式。须下盆沉积体系受西低东高大型缓坡古地貌特征控制,总体具有不对称分布特点,湖盆中心位于川西坳陷中南段;前陆造山对须上盆沉积体系分布具有明显的控制作用,沉积体系呈近于对称的环带状分布,前陆隆起及湖盆东移,湖盆走向明显的受古龙门山控制。 展开更多
关键词 四川盆地 晚三叠世 沉积体系 层序地层格架 砂体分布 基准面旋回层序 沉积演化特征 造山旋回
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Fischer图解及其在旋回层序研究中的应用──以北京西山张夏组为例 被引量:32
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作者 苏德辰 李庆谋 +1 位作者 罗光文 梅冥相 《现代地质》 CAS CSCD 1995年第3期279-283,共5页
Fischer图解(又称为容纳空间图解)为人们研究沉积旋回在空间上的叠置规律、相对海平面变化、层序级次的划分以及地层层序对比等提供了一种客观实用的方法。本文较详细地讨论了该图解的绘制方法及应注意的问题。运用该图解,将... Fischer图解(又称为容纳空间图解)为人们研究沉积旋回在空间上的叠置规律、相对海平面变化、层序级次的划分以及地层层序对比等提供了一种客观实用的方法。本文较详细地讨论了该图解的绘制方法及应注意的问题。运用该图解,将北京西山下苇甸剖面张夏组划分为1个大的三级旋回层序和4个四级旋回层序,根据图解反映的相对海平面变化讨论了旋回层序与构造运动间的关系,提出华北板块晚寒武世之前的"翘翘板运动"应始于中寒武世张夏期之早期到中期。 展开更多
关键词 旋回层序 张夏组 容纳空间图解 地层 寒武纪
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华北地台中寒武世鲕滩碳酸盐旋回沉积、古海平面变动控制及旋回年代学研究 被引量:27
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作者 柳永清 孟祥化 葛铭 《地质科学》 CAS CSCD 北大核心 1999年第4期442-450,共9页
华北地台中寒武世鲕滩碳酸盐沉积序列中具有特征的低频 ( 级 )和高频 ( 级- 级 )旋回层序叠加样式和规律。旋回层序内部的沉积构成、微相组构、成岩特点以及高频旋回的复合、叠加严格受复合海平面变动的控制。巨厚鲕滩形成于低频海平... 华北地台中寒武世鲕滩碳酸盐沉积序列中具有特征的低频 ( 级 )和高频 ( 级- 级 )旋回层序叠加样式和规律。旋回层序内部的沉积构成、微相组构、成岩特点以及高频旋回的复合、叠加严格受复合海平面变动的控制。巨厚鲕滩形成于低频海平面变化的回落时期 ,但复合叠加于低频海平面变化中的 级海平面变化更直接地控制着鲕滩建造的时空发育、进积迁移。鲕滩微相中鲕粒组构特征则主要与高频海平面变化相关。鲕滩高频海平面变化旋回层序的厚度频率分布、不同级次旋回叠加比率和样式以及大范围空间上的连续可比性规律可能说明它们受地球轨道参数周期性变动的控制。轨道旋回层序具有的特定变化时间周期和频率使得旋回地层学具有了年代学意义 ,可以对重要地层段、事件层及生物带高精度测年。应用旋回地层学的研究得到了中寒武世毛庄 \徐庄 \张夏期的界线 (面 )年龄 ,即毛庄 (期 ) \徐庄 (期 )为 530 .50 Ma、徐庄 (期 ) \张夏 (期 )为 52 6.90 Ma,与前人应用生物年代地层学等方法得到的年龄值极为一致。 展开更多
关键词 中寒武世 碳酸盐鲕滩 沉积 旋回年代学 古海平面
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塔巴庙区块山西组高分辨率层序地层学研究 被引量:11
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作者 李君文 陈洪德 +2 位作者 田景春 侯中健 刘文均 《油气地质与采收率》 CAS CSCD 北大核心 2005年第5期1-4,共4页
以高分辨率层序地层学理论为指导,以露头剖面、钻井岩心、测井资料的综合研究为基础,研究了塔巴庙区块下二叠统山西组的高分辨率层序地层学特征,识别和划分了一个超长期、两个长期、六个中期及若干个短期基准面旋回层序。详细分析了不... 以高分辨率层序地层学理论为指导,以露头剖面、钻井岩心、测井资料的综合研究为基础,研究了塔巴庙区块下二叠统山西组的高分辨率层序地层学特征,识别和划分了一个超长期、两个长期、六个中期及若干个短期基准面旋回层序。详细分析了不同级次基准面旋回层序的叠加式样、沉积序列、岩性岩相组合等特征。在此基础上,讨论了基准面旋回层序与天然气富集的关系,认为主要气层段主要处于长期及中期旋回的底部,即基准面上升阶段的早期或湖平面下降的低水位时期及湖侵期的开始时期。 展开更多
关键词 高分辨率层序地层学 山西组 基准面旋回层序 天然气 塔巴庙区块
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