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Science China Earth Sciences 2008年第2期51卷 187-193页

作者： PENG XingFang FENG QingLai Li ZhouBo MENG YouYan MOE Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China Faculty of Mathematics and Physics China University of GeosciencesWuhan 430074China Guangxi Geological Survey Research Institute Nanning 530031China

Spectral analysis is applied to geochemical data from a deep-water Permian-Triassic Boundary (PTB) section across PTB in Dongpan, Guangxi for high-resolution cyclostratigraphic research. The characteristics of the Milankovitch Cycles have been well recorded in the strata of the Dongpan section. Spectrum on Ce/La records shows especially that the ratios among its three preponderant cycles in the section are 5:2:1, which well displays the phenomenon of the sedimentary cycles driven by orbital force. The Milankovitch theory is further confirmed by the Paleozoic records.

关键词： spectral analysis P/T boundary geochemistry cyclostratigraphy Guangxi

The Ordovician Magnetostratigraphy and cyclostratigraphy:A Review

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Acta Geologica Sinica(English Edition) 2019年第S1期93卷 94-97页

作者： DAI Shuang LUO Junhua Mark DEKKERS WANG Weiguo QIANG Xiaoke WU Huaichun QIANG Lei TIAN Chao XI Haiyu Wout KRIJISMAN School of Earth Sciences and Key Laboratory of Mineral Resources in Western China(Gansu Province) Lanzhou UniversityLanzhou 730000China Key Laboratory of Western China’s Environmental Systems Ministry of Education of China&College of Resources and EnvironmentLanzhou UniversityLanzhouGansu 730000China Paleomagnetic Laboratory’Fort Hoofddijk’ Utrecht University3584 CD UtrechtThe Netherlands Lab of Coast and Ocean Geology Third Institute of OceanographyState Oceanic AdministrationXiamen361005China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710075China State Key Laboratory of Biogeology and Environmental Geology and School of Ocean Sciences China University of GeosciencesBeijing 100083China

The study of magnetostratigraphy and cyclostratigraphy in the last two decades has provided a great deal of opportunities to improve the geologic time scale.The Cenozoic and Mesozoic geologic timescale have been well calibrated(Gradstein et al..2012;Ogg et al,2012;Cohen et al.,2018).However,for the Paleozoic era the uncertainty over boundary ages are still very large.

关键词： magnetostratigraphy geomagnetic polarity timescale cyclostratigraphy geologic timescale Ordovician

cyclostratigraphy of the Induan (Early Triassic) in West Pingdingshan Section,Chaohu,Anhui Province

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Science China Earth Sciences 2008年第1期51卷 22-29页

作者： GUO Gang TONG JinNan ZHANG ShiHong ZHANG Jie BAI LingYan GPMR and BGEG Laboratories at China University of Geosciences Wuhan 430074China School of the Earth Sciences and Resources China University of GeosciencesBeijing 100083China

The Induan sequence in the West Pingdingshan Section, Chaohu, Anhui Province, displays a series of superimposed mudstone/limestone cycles. The lithological character of the cycles, combined with power spectral and wavelet analysis of magnetic susceptibility readings, reveals 12 short eccentricity and 56 precession Milankovitch cycles - obliquity cycles are not apparent. The uniformity of cycle thicknesses indicates a stable depositional setting making this section ideal to perform various geo-logical studies. Accordingly, the Induan Stage is estimated to have lasted 1.1 Ma, and the depositional rate for this part of the section is about 3.7 cm/ka. This places the Induan-Olenekian boundary in the West Pingdingshan Section at about 251.5 Ma based on an age of 252.6 Ma for the Permian-Triassic boundary.

关键词： Induan cyclostratigraphy magnetic susceptibility spectral analysis wavelet analysis Chaohu Anhui Province

cyclostratigraphy Data as a Proxy for Geoelectrical Data Interpretation: Application to Phosphate Minerals Exploration in Matam (Senegal)

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Open Journal of Geology 2014年第10期4卷 551-570页

作者： Mapathe Ndiaye Seydou Coulibaly Winimi Saratou Zouwinaba Issa Ba Laboratoire de Mécanique et Modélisation University of Thies Thies Senegal

The vertical electrical soundings on the Matam region phosphates deposits are interpreted by inversion. To retrieve lithology from the obtained resistivities, mechanical drilling was performed to compare directly the lithologies and the geoelectrical resistivities. The obtained relation is not simple and is not sufficient to interpret all the VES. This situation motivated the collection of supplementary information from cyclostratigraphy. Geoelectrical and cyclostratigraphic?information is combined using fuzzy logic techniques to build a fuzzy inference system. The obtained results seem to be consistent with the stratigraphy of the investigated region and allow retrieving lithological succession. Further investigations are necessary for more accurate thickness determination.

关键词： cyclostratigraphy Geoelectrical Vertical Electrical Sounding Phosphate Matam Fuzzy Logic

Magnetic field hyperactivity during the early Neoproterozoic: A paleomagnetic and cyclostratigraphic study of the Katav Formation, southern Urals, Russia

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Geoscience Frontiers 2023年第4期14卷 42-56页

作者： Inessa V.Golovanova Konstantin N.Danukalov Raushaniia Yu.Salmanova Natalia M.Levashova Nikita P.Parfiriev Nina D.Sergeeva Joseph G.Meert Institute of Geology-Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences(IG UFRC RAS) Russia Geological Institute Russian Academy of SciencesMoscowRussia Department of Earth and Planetary Sciences Neil Opdyke Paleomagnetic LaboratoryUniversity of FloridaGainesvilleFL 32611United States

We present a detailed magnetostratigraphic and cyclostratigraphic profile through the Riphean(Tonian)Katav Formation in the southern Urals.The study confirms the primary nature of the magnetization in these rocks.The cyclostratigraphic study identified several orbital periods including the 405 ka long eccentricity.This allows us to quantify the reversal frequency in the Katav and our estimates range of 7–12 reversals per million years.Based on our study,we identify an interval of magnetic field reversal hyperactivity in the Neoproterozoic interval.Age estimates for the Katav are contentious and range somewhere between 800 Ma and 900 Ma based on carbonate Pb-Pb ages and stable isotope correlations.The paleomagnetic poles obtained in this study of the Katav(and overlying Inzer)Formation do not fit anywhere on the Baltica apparent polar wander path between 1100 Ma and 900 Ma.Furthermore,they lie 90away from the 900 Ma segment of the path.We tentatively estimate their age to be closer to 800 Ma and perhaps confirm a previously hypothesized pulse of rapid true polar wander between 825 Ma and 790 Ma.

关键词： Magnetostratigraphy cyclostratigraphy Hyperactive reversal True polar wander Tonian

cyclostratigraphy Study on Upper Cretaceous Eastern Tethys

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地学前缘 2009年第S1期16卷 268-268页

作者： Chao Ma,Chengshan Wang,Xi Chen,Yongjian Huang,Yan Zheng,Meng Wang 1.China University of Geosciences(Beijing),Beijing 100083,China. 2.Research Center for Tibetan Plateau Geology,China University of Geosciences(Beijing),Beijing 100083,China

The cyclostratigraphy study is increasingly important in the precise dating of the marine strata, especially in the Tethyan realm.Compared with the Western Tethys,the cyclostratigraphy study on the Eastern Tethys is relatively insufficient.Cretaceous marine sediments are cropped out widely in Southern Tibet,among them the late Cretaceous in the Gongzha section of Tingri area is rather continuous and integral.

关键词： Southern Tibet Tingri Upper Cretaceous Coniacian cyclostratigraphy

A case study on how astronomical cycles affect the organic carbon accumulation

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Journal of Palaeogeography 2023年第4期12卷 637-651页

作者： Yang Li Ren-Chao Yang Carlos Zavala Liang Dong Valentin Trobbiani Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071Shandong ProvinceChina Geology Department Universidad Nacional del SurBahía Blanca 8000Argentina Geología de Cuencas Sedimentarias(GCS)Argentina Bahía Blanca 8000Argentina

The paleoclimate change impacts the sedimentary environment and process,which in turn control the accumulation of organic carbon.Numerous studies have shown that the paleoclimate is controlled by astronomical cycles.Hence,understanding how these cycles impact the accumulation of organic carbon is a critical question that requires in-depth discussion.Previous studies have shown that Milankovitch cycle can be revealed from the sediments of the 7^(th)Oil Member(Chang 7 Member for short)of the Triassic Yanchang Formation in the southern Ordos Basin,suggesting that the deposition was controlled by astronomically-forced climate changes.Building on previous research,this study collected natural gamma(GR)data of Chang 7 Member from the N36 Well to further analyze astronomical cycles,combined with X-ray fluorescence(XRF)analysis and total organic carbon(TOC)tests,to reconstruct the paleoenvironment and analyze the organic matter enrichment characteristics.The results of this contribution show that,paleoclimate,paleo-redox conditions,paleo-water level,paleo-productivity and sediment accumulation rate(SAR)collectively controlled the enrichment of organic matter.Notably,this study identified the presence of eccentricity,obliquity,precession,and the 1.2 Myr long obliquity cycle in the Chang 7 Member.These cycles controlled the paleoenvironmental changes at different timescales and influenced the enrichment of organic matter,which has implications for subsequent energy exploration.

关键词： cyclostratigraphy Milankovitch cycle Organic matter enrichment Paleoenvironmental Ordos Basin Chang 7 Member

Nonmarine time-stratigraphy in a rift setting: An example from the Mid-Permian lower Quanzijie low-order cycle, Bogda Mountains, NW China

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Journal of Palaeogeography 2015年第1期4卷 27-51页

作者： Jonathan Obrist-Farner Wan Yang Geology and Geophysics Program Missouri University of Science and TechnologyRolla Missouri 65409 USA Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences

Sedimentological and stratigraphic studies of seven stratigraphic sections of Permian Hongyanchi （HYC） and Quanzijie （QZJ） low-order cycles （LCs） in the Tarlong-Taodonggou half graben and Dalongkou area in Bogda Mountains, NW China, demonstrate effective approaches and methodology in cyclo- and time-stratigraphic analyses of complex fluviallacustrine deposits in an intracontinental rift setting. A new synchronous stratigraphic unit, the lower QZJ LC is defined. The lower and upper boundaries of this cycle include a regionally correlative disconformity, erosional unconformity, and conformity, across which significant and abrupt changes in palaeoenvironments and tectonic and climatic conditions occurred. The lower boundary is an erosional unconformity and disconformity with a high-relief topography that juxtaposes lacustrine deposits of the underlying HYC LC with the overlying meandering stream deposits of the lower QZJ LC, and was caused by a regional tectonic uplift. The up- per boundary is a disconformity and local erosional unconformity and conformity, juxtaposing stacked paleosols developed on fluvial sediments with overlying fluvial and loessial deposits of the upper QZJ LC. The paleosols indicate landscape stability and a prolonged period of subaerial exposure and minimal deposition and suggest that climatic conditions were semiarid with strong precipitation seasonality in the Tarlong-Taodonggou half graben and subhumid in the Dalongkou area. The fluvial-loessial deposits indicate a renewed tectonic uplift and a change in the atmospheric circulation pattern. The newly-defined lower QZJ LC facilitates accurate palaeogeographic reconstruction in the study area during a period of major tectonic and climatic changes. The interpreted tectonic and climatic conditions provide a critical data point in the mid-latitude east coast of NE Pangea during the Mid-Permian icehouse-hothouse transition. The results demonstrate that a process-response approach is effective in time- stratigraphic analysis of complex fluvial-lac

关键词： fluvial loess cyclostratigraphy Permian China

Effects of astronomical orbital cycle and volcanic activity on organic carbon accumulation during Late Ordovician–Early Silurian in the Upper Yangtze area, South China

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Petroleum Exploration and Development 2021年第4期48卷 850-863页

作者： ZHANG Xi ZHANG Tingshan ZHAO Xiaoming ZHU Haihua MIHAI Emilian Popa CHEN Lei YONG Jinjie XIAO Qiang LI Hongjiao School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China Faculty of Geology and Geophysics University of BucharestBucharest 010041Romania

Based on field outcrop data,the effects of cyclic change of astronomical orbit and volcanic activity on organic carbon accumulation during the Late Ordovician-Early Silurian in the Upper Yangtze area were studied using cyclostratigraphic and geochemical methods.d13 C and chemical index of alteration(CIA)were used to filter the astronomical orbit parameters recorded in sediments.It is found that the climate change driven by orbital cycle controls the fluctuations of sea level at different scales,obliquity forcing climate changes drive thermohaline circulation(THC)of the ocean,and THC-induced bottom currents transport nutrient-laden water from high latitude regions to the surface water of low-latitude area.Hence,THC is the main dynamic mechanism of organic-carbon supply.The marine productivity indexes of Ba/Al and Ni/Al indicate that volcanic activities had limited effect on marine productivity but had great influences on organic carbon preservation efficiency in late Hirnantian(E4).Paleo-ocean redox environmental indicators Th/U,V/Cr and V/(V+Ni)show that there is a significant correlation between volcanism and oxygen content in Paleo-ocean,so it is inferred that volcanisms controlled the organic carbon preservation efficiency by regulating oxygen content in Paleo-ocean,and the difference in volcanism intensity in different areas is an important factor for the differential preservation efficiency of organic carbon.The organic carbon input driven by orbital cycle and the preservation efficiency affected by volcanisms worked together to control the enrichment of organic carbon in the Middle–Upper Yangtze region.

关键词： cyclostratigraphy organic carbon accumulation geochemical weathering index thermohaline circulation volcanic activity Upper Ordovician Wufeng Formation Lower Silurian Longmaxi Formation

Cretaceous integrative stratigraphy and timescale of China

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Science China Earth Sciences 2019年第1期62卷 256-286页

作者： Dangpeng XI Xiaoqiao WAN Guobiao LI Gang LI State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

Cretaceous strata are widely distributed across China and record a variety of depositional settings. The sedimentary facies consist primarily of terrestrial, marine and interbedded marine-terrestrial deposits, of which marine and interbedded facies are relatively limited. Based a thorough review of the subdivisions and correlations of Cretaceous strata in China, we provide an up-to-date integrated chronostratigraphy and geochronologic framework of the Cretaceous system and its deposits in China.Cretaceous marine and interbedded marine-terrestrial sediments occur in southern Tibet, Karakorum, the western Tarim Basin,eastern Heilongjiang and Taiwan. Among these, the Himalayan area has the most complete marine deposits, the foraminiferal and ammonite biozonation of which can be correlated directly to the international standard biozones. Terrestrial deposits in central and western China consist predominantly of red, lacustrine-fluvial, clastic deposits, whereas eastern China, a volcanically active zone, contains clastic rocks in association with intermediate to acidic igneous rocks and features the most complete stratigraphic successions in northern Hebei, western Liaoning and the Songliao Basin. Here, we synthesise multiple stratigraphic concepts and charts from southern Tibet, northern Hebei to western Liaoning and the Songliao Basin to produce a comprehensive chronostratigraphic chart. Marine and terrestrial deposits are integrated, and this aids in the establishment of a comprehensive Cretaceous chronostratigraphy and temporal framework of China. Further research into the Cretaceous of China will likely focus on terrestrial deposits and mutual authentication techniques(e.g., biostratigraphy, chronostratigraphy, magnetostratigraphy and cyclostratigraphy). This study provides a more reliable temporal framework both for studying Cretaceous geological events and exploring mineral resources in China.

关键词： Cretaceous Stage/age Biostratigraphy Chronostratigraphy Magnetostratigraphy cyclostratigraphy Stratigraphic correlation China