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Source modeling of the 2023 Herat earthquake sequence determined from InSAR observations
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作者 Jiong Fu Yunguo Chen +2 位作者 Qixiang Nie Zhipeng Lv Jingwei Li 《Geodesy and Geodynamics》 2025年第5期624-634,共11页
During 7th-15th October 2023,an earthquake sequence with four MW6.2-6.3 occurred in the Herat region,Afghanistan,causing damage to buildings,fire,and loss of life.The co-seismic deformation induced by the earthquake s... During 7th-15th October 2023,an earthquake sequence with four MW6.2-6.3 occurred in the Herat region,Afghanistan,causing damage to buildings,fire,and loss of life.The co-seismic deformation induced by the earthquake sequence helps us invert the rupture model of these earthquakes to constrain the geometric characteristics of the Herat fault system,and estimate the future seismic risk at this fault system.In this work,we utilized the line-of-sight(LOS)displacements from Interferometric Synthetic Aperture Radar(InSAR)observations to determine the optimal fault geometry and slip distribution of the 2023 Afghanistan earthquake sequence through a two-step inversion method.Our results indicated that these four MW6.2-6.3 earthquakes ruptured the western and northwestern segments of the Herat fault system,which are dominated by thrust motions.We identified two fault models from InSAR LOS displacement data,with two different strikes,and the same dip angle range of about 35-45°.The source model with the strike of 280.5°has a peak slip of about 2.2 m,a central rupture zone with about 25 km along-strike length,and a depth range of 5-10 km,corresponding to a MW6.67 earthquake.The following source model with the strike direction of about 240°has smaller rupture length and width,and a peak slip of about 2.5 m,corresponding to a MW6.65 earthquake.We also calculated the Coulomb Failure Stress of the Herat fault system around this rupture area caused by this earthquake sequence.Our results indicated that the stress loading at the western segment of the Herat Fault system is greater than the triggering threshold,suggesting that the future seismic risk in this area is at a relatively high stage.In summary,the rupture model of these earthquakes indicates that two unidentified thrust faults between the western and northwestern segments of the Herat fault system are in a compression-stress environment. 展开更多
关键词 2023 Herat earthquake sequence Co-seismic LOS displacements Source modeling Coulomb failure stress
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Bayesian-based analysis of sequence activity characteristics in the Bohai Rim region
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作者 Bi Jin-Meng Song Cheng Cao Fu-Yang 《Applied Geophysics》 2025年第2期237-251,554,共16页
Disaster mitigation necessitates scientifi c and accurate aftershock forecasting during the critical 2 h after an earthquake. However, this action faces immense challenges due to the lack of early postearthquake data ... Disaster mitigation necessitates scientifi c and accurate aftershock forecasting during the critical 2 h after an earthquake. However, this action faces immense challenges due to the lack of early postearthquake data and the unreliability of forecasts. To obtain foundational data for sequence parameters of the land-sea adjacent zone and establish a reliable and operational aftershock forecasting framework, we combined the initial sequence parameters extracted from envelope functions and incorporated small-earthquake information into our model to construct a Bayesian algorithm for the early postearthquake stage. We performed parameter fitting and early postearthquake aftershock occurrence rate forecasting and effectiveness evaluation for 36 earthquake sequences with M ≥ 4.0 in the Bohai Rim region since 2010. According to the results, during the early stage after the mainshock, earthquake sequence parameters exhibited relatively drastic fl uctuations with signifi cant errors. The integration of prior information can mitigate the intensity of these changes and reduce errors. The initial and stable sequence parameters generally display advantageous distribution characteristics, with each parameter’s distribution being relatively concentrated and showing good symmetry and remarkable consistency. The sequence parameter p-values were relatively small, which indicates the comparatively slow attenuation of signifi cant earthquake events in the Bohai Rim region. A certain positive correlation was observed between earthquake sequence parameters b and p. However, sequence parameters are unrelated to the mainshock magnitude, which implies that their statistical characteristics and trends are universal. The Bayesian algorithm revealed a good forecasting capability for aftershocks in the early postearthquake period (2 h) in the Bohai Rim region, with an overall forecasting effi cacy rate of 76.39%. The proportion of “too low” failures exceeded that of “too high” failures, and the number of forecasting failures for the next three days was greater than that for the next day. 展开更多
关键词 earthquake sequences Bayesian algorithm model parameters correlation analysis effectiveness evaluation
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Single-cell sequencing reveals the features of adaptive immune responses in the liver of a mouse model of dengue fever
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作者 Yizhen Yuan Qian Chen +3 位作者 Zhe Li Fangzhou Cai Dan Li Wei Wang 《Animal Models and Experimental Medicine》 2025年第1期30-43,共14页
Background:Dengue fever,an acute insect-borne infectious disease caused by the dengue virus(DENV),poses a great challenge to global public health.Hepatic involve-ment is the most common complication of severe dengue a... Background:Dengue fever,an acute insect-borne infectious disease caused by the dengue virus(DENV),poses a great challenge to global public health.Hepatic involve-ment is the most common complication of severe dengue and is closely related to the occurrence and development of disease.However,the features of adaptive immune responses associated with liver injury in severe dengue are not clear.Methods:We used single-cell sequencing to examine the liver tissues of mild or se-vere dengue mice model to analyze the changes in immune response of T cells in the liver after dengue virus infection,and the immune interaction between macrophages and T cells.Flow cytometry was used to detect T cells and macrophages in mouse liver and blood to verify the single-cell sequencing results.Results:Our result showed CTLs were significantly activated in the severe liver injury group but the immune function-related signal pathway was down-regulated.The rea-son may be that the excessive immune response in the severe group at the late stage of DENV infection induces the polarization of macrophages into M2 type,and the macrophages then inhibit T cell immunity through the TGF-βsignaling pathway.In ad-dition,the increased proportion of Treg cells suggested that Th17/Treg homeostasis was disrupted in the livers of severe liver injury mice.Conclusions:In this study,single-cell sequencing and flow cytometry revealed the characteristic changes of T cell immune response and the role of macrophages in the liver of severe dengue fever mice.Our study provides a better understanding of the pathogenesis of liver injury in dengue fever patients. 展开更多
关键词 adaptive immunity dengue fever model liver injury single-cell sequencing
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A cloud model target damage effectiveness assessment algorithm based on spatio-temporal sequence finite multilayer fragments dispersion
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作者 Hanshan Li Xiaoqian Zhang Junchai Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期48-64,共17页
To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage p... To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage probability leveraging spatio-temporal finite multilayer fragments distribution and the target damage assessment algorithm based on cloud model theory.Drawing on the spatial dispersion characteristics of fragments of projectile proximity explosion,we divide into a finite number of fragments distribution planes based on the time series in space,set up a fragment layer dispersion model grounded in the time series and intersection criterion for determining the effective penetration of each layer of fragments into the target.Building on the precondition that the multilayer fragments of the time series effectively assail the target,we also establish the damage criterion of the perforation and penetration damage and deduce the damage probability calculation model.Taking the damage probability of the fragment layer in the spatio-temporal sequence to the target as the input state variable,we introduce cloud model theory to research the target damage assessment method.Combining the equivalent simulation experiment,the scientific and rational nature of the proposed method were validated through quantitative calculations and comparative analysis. 展开更多
关键词 Target damage Cloud model Fragments dispersion Effectiveness assessment Spatio-temporal sequence
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3D static modeling and sequence stratigraphy using well logs and seismic data:An example of Abu Roash G member in Bahga oilfield
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作者 Mohamed Reda Mohamed Fathy +2 位作者 Mohamed Mosaad Fahad Alshehri Mohamed S.Ahmed 《Energy Geoscience》 EI 2024年第3期362-377,共16页
This research uses both three-dimensional(3D)modeling and geologic well control to piece back together the architectural parts of the Late Cretaceous formations.The goal is to figure out the sizes,directions,locations... This research uses both three-dimensional(3D)modeling and geologic well control to piece back together the architectural parts of the Late Cretaceous formations.The goal is to figure out the sizes,directions,locations,and controls of the layers of the fluvial sandstone reservoirs.Sequence stratigraphy is essential for 3D reservoir modeling and petroleum geology understanding in the Bahga oilfield.The purpose of this work is to create a static model that shows the layers and facies distribution in the reservoir interval.We will use data from nine well logs and 22 seismic lines calibrated by the Abu Roash G Member reservoir core intervals to accomplish this.The petrophysical study discovered three parts in the Abu Roash G Member reservoir rock:channel fill that is affected by tides,channel fill that is dominated by tides(intertidal sands),and channel top with lenticular bedded sandstone.The model's findings point to the existence of an NNW-oriented sand body,which could be a prime location to produce hydrocarbons.The original oil in place(OOIP)is about 3,438,279 Stock Tank Barrels(STB),and the oil reserve reaches up to 1,031,484(STB).Sequence stratigraphic analysis using seismic and well log information(SB)reveals that the Upper Cretaceous AR/G reservoir of the Bahga field is characterized by third-and fourth-order stratigraphic sequences,which are constrained by three Maximum Flooding Surfaces(MFS)and two Sequence Boundaries.The integration of the derived geological model and sequence stratigraphic results can lower future extraction risk by identifying the locations and trends of the geologic facies with the necessary petrophysical properties for the hydrocarbon accumulations. 展开更多
关键词 Three-dimensional reservoir modeling sequence stratigraphy Reservoir characterization Abu Roash reservoir Abu Gharadig Basin
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Development characteristics of the third-order sequence of Upper Devonian–Lower Carboniferous shore-mixed shelf in Tarim Basin, NW China
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作者 MA Qing MA Tao +2 位作者 YANG Haijun ZHAO Xueqin ZHU Yiqing 《Petroleum Exploration and Development》 2019年第4期701-710,共10页
Based on the study of stratigraphic sedimentary facies of the prototype sedimentary basin formed in the Late Devonian to Permian Period in the Tarim Basin, the prototype sedimentary basin are divided into five order s... Based on the study of stratigraphic sedimentary facies of the prototype sedimentary basin formed in the Late Devonian to Permian Period in the Tarim Basin, the prototype sedimentary basin are divided into five order sequences according to the theory of sequence stratigraphy. It is considered that the Upper Devonian–Lower Carboniferous shore-mixing shelf in the lower part of the prototype sedimentary basin is a typical third-order sequence and a sequence development model is established. The third-order sequence is actually a transgression systems tract and highstand systems tract cycle assemblage, and the type I sequence(no lowstand systems tract) is a typical developmental mode of the third order sequence, and the identification mark is the existence of huge mudstone and limestone wedges from sea to land. The fifth-order parasequence is the basic sequence, which is a single cycle sequence. The thin layer limestone isochronous sediments, which are easy to be identified in the mixed shelf areas, are the isochronous sediments of the largest or secondary marine-flooding surface. The mixed shelf area belongs to the equilibrium sedimentary profile of internal and external sediments, and there is no condensed section. The inclined deposition phenomenon of extraneous source sediments in the sea area weakens or disappears in the mixed shelf area. The paleogeomorphology at the bottom of the third-order sequence is a terrace-slope break zone. This paleogeomorphological feature is not only the main reason for the sedimentary diachronism of Donghe sandstone, but also the main reason for the formation of the transgression-highstand fourth-order cyclic sequences of the Donghe sandstone section and its upper gravel-bearing sandstone section. 展开更多
关键词 SHORE MIXED SHELF TARIM BASIN prototype sedimentary BASIN sequence stratigraphy third-order sequence model
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Optimal state and branch sequence based parameter estimation of continuous hidden Markov model
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作者 俞璐 吴乐南 谢钧 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期136-140,共5页
A parameter estimation algorithm of the continuous hidden Markov model isintroduced and the rigorous proof of its convergence is also included. The algorithm uses theViterbi algorithm instead of K-means clustering use... A parameter estimation algorithm of the continuous hidden Markov model isintroduced and the rigorous proof of its convergence is also included. The algorithm uses theViterbi algorithm instead of K-means clustering used in the segmental K-means algorithm to determineoptimal state and branch sequences. Based on the optimal sequence, parameters are estimated withmaximum-likelihood as objective functions. Comparisons with the traditional Baum-Welch and segmentalK-means algorithms on various aspects, such as optimal objectives and fundamentals, are made. Allthree algorithms are applied to face recognition. Results indicate that the proposed algorithm canreduce training time with comparable recognition rate and it is least sensitive to the training set.So its average performance exceeds the other two. 展开更多
关键词 continuous hidden Markov model optimal state and branch sequence MAXIMUMLIKELIHOOD CONVERGENCE viterbi algorithm
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Identification and validation of a pyroptosis-related prognostic model for colorectal cancer based on bulk and single-cell RNA sequencing data 被引量:2
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作者 Li-Hua Zhu Jun Yang +3 位作者 Yun-Fei Zhang Li Yan Wan-Rong Lin Wei-Qing Liu 《World Journal of Clinical Oncology》 2024年第2期329-355,共27页
BACKGROUND Pyroptosis impacts the development of malignant tumors,yet its role in colorectal cancer(CRC)prognosis remains uncertain.AIM To assess the prognostic significance of pyroptosis-related genes and their assoc... BACKGROUND Pyroptosis impacts the development of malignant tumors,yet its role in colorectal cancer(CRC)prognosis remains uncertain.AIM To assess the prognostic significance of pyroptosis-related genes and their association with CRC immune infiltration.METHODS Gene expression data were obtained from The Cancer Genome Atlas(TCGA)and single-cell RNA sequencing dataset GSE178341 from the Gene Expression Omnibus(GEO).Pyroptosis-related gene expression in cell clusters was analyzed,and enrichment analysis was conducted.A pyroptosis-related risk model was developed using the LASSO regression algorithm,with prediction accuracy assessed through K-M and receiver operating characteristic analyses.A nomo-gram predicting survival was created,and the correlation between the risk model and immune infiltration was analyzed using CIBERSORTx calculations.Finally,the differential expression of the 8 prognostic genes between CRC and normal samples was verified by analyzing TCGA-COADREAD data from the UCSC database.RESULTS An effective pyroptosis-related risk model was constructed using 8 genes-CHMP2B,SDHB,BST2,UBE2D2,GJA1,AIM2,PDCD6IP,and SEZ6L2(P<0.05).Seven of these genes exhibited differential expression between CRC and normal samples based on TCGA database analysis(P<0.05).Patients with higher risk scores demonstrated increased death risk and reduced overall survival(P<0.05).Significant differences in immune infiltration were observed between low-and high-risk groups,correlating with pyroptosis-related gene expression.CONCLUSION We developed a pyroptosis-related prognostic model for CRC,affirming its correlation with immune infiltration.This model may prove useful for CRC prognostic evaluation. 展开更多
关键词 Colorectal cancer PYROPTOSIS Single-cell RNA sequencing Immune infiltration Prognostic model
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Interval grey number sequence prediction by using non-homogenous exponential discrete grey forecasting model 被引量:20
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作者 Naiming Xie Sifeng Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期96-102,共7页
This paper aims to study a new grey prediction approach and its solution for forecasting the main system variable whose accurate value could not be collected while the potential value set could be defined. Based on th... This paper aims to study a new grey prediction approach and its solution for forecasting the main system variable whose accurate value could not be collected while the potential value set could be defined. Based on the traditional nonhomogenous discrete grey forecasting model(NDGM), the interval grey number and its algebra operations are redefined and combined with the NDGM model to construct a new interval grey number sequence prediction approach. The solving principle of the model is analyzed, the new accuracy evaluation indices, i.e. mean absolute percentage error of mean value sequence(MAPEM) and mean percent of interval sequence simulating value set covered(MPSVSC), are defined and, the procedure of the interval grey number sequence based the NDGM(IG-NDGM) is given out. Finally, a numerical case is used to test the modelling accuracy of the proposed model. Results show that the proposed approach could solve the interval grey number sequence prediction problem and it is much better than the traditional DGM(1,1) model and GM(1,1) model. 展开更多
关键词 grey number grey system theory INTERVAL discrete grey forecasting model non-homogeneous exponential sequence
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A Climatic Sequence Stratigraphic Model in the Terrestrial Lacustrine Basin:A Case Study of Green River Formation,Uinta Basin,USA 被引量:5
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作者 WANG Junling ZHENG Herong +3 位作者 XIAO Huanqin ZHONG Guohong Ronald STEEL YIN Peigui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第1期130-135,共6页
In recent years, with the development of terrestrial sequence stratigraphy, more attention has been focused on the study of the terrestrial lacustrine sequence stratigraphic model globally. Different viewpoints are pr... In recent years, with the development of terrestrial sequence stratigraphy, more attention has been focused on the study of the terrestrial lacustrine sequence stratigraphic model globally. Different viewpoints are preferred by researchers. Under the guidance of the theory of sequence stratigraphy, the findings of this paper indicate that climate is a major factor controlling the formation of the fourth-order sequence, based upon the study of the sequence stratigraphy in the Green River Formation of the Uinta basin in the USA. It also divides the fourth-order sequence in the terrestrial lacustrine basin into two system tracts: the wet (rising) half-cycle and the dry (falling) half- cycle, establishing a new-style fourth-order sequence stratigraphic model for the terrestrial lacustrine basin, that is, the climate-genetic sequence stratigraphic model. As a result, the theory of sequence stratigraphy is greatly enriched. 展开更多
关键词 CLIMATE fourth-order sequence sequence stratigraphic model terrestrial lacustrine basin Green River Formation Uinta basin
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Chaos game representation(CGR)-walk model for DNA sequences 被引量:4
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作者 高洁 徐振源 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第1期370-376,共7页
Chaos game representation (CGR) is an iterative mapping technique that processes sequences of units, such as nucleotides in a DNA sequence or amino acids in a protein, in order to determine the coordinates of their ... Chaos game representation (CGR) is an iterative mapping technique that processes sequences of units, such as nucleotides in a DNA sequence or amino acids in a protein, in order to determine the coordinates of their positions in a continuous space. This distribution of positions has two features: one is unique, and the other is source sequence that can be recovered from the coordinates so that the distance between positions may serve as a measure of similarity between the corresponding sequences. A CGR-walk model is proposed based on CGR coordinates for the DNA sequences. The CGR coordinates are converted into a time series, and a long-memory ARFIMA (p, d, q) model, where ARFIMA stands for autoregressive fractionally integrated moving average, is introduced into the DNA sequence analysis. This model is applied to simulating real CGR-walk sequence data of ten genomic sequences. Remarkably long-range correlations are uncovered in the data, and the results from these models are reasonably fitted with those from the ARFIMA (p, d, q) model. 展开更多
关键词 CGR-walk model DNA sequence LONG-MEMORY ARFIMA(p d q) model
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On the Carboniferous Sequence Stratigraphy in the Tazhong Area, Xinjiang——A Model of the Sequence Stratigraphy Framework of Intracratonic Depressional Basins 被引量:4
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作者 Guo Jianhua Zeng Yunfu Zhai Yonghong and Gao Zhenzhong Jianghan Petroleum Institute, Jingsha, Hubei Chengdu Institute of Technology, Chengdu, Sichuan Jianghan Petroleum Institute, Jingsha, Hubei Liu Xinzhu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第3期328-343,共16页
The Carboniferous prototype sedimentary basin in the Tazhong (Central Tarimbasin) area is recognized as a compressive intracratonic depressional one. Three type Ⅰ sequenceboundaries and three type Ⅱ sequence boundar... The Carboniferous prototype sedimentary basin in the Tazhong (Central Tarimbasin) area is recognized as a compressive intracratonic depressional one. Three type Ⅰ sequenceboundaries and three type Ⅱ sequence boundaries can be identified in the CarboniferousSystem, which can accordingly be divided into five sedimentary sequences. These sequencespossess stratigraphic characters of the standard sequence and correspond to the depositionalstratigraphic unit of a third-order eustatic cycle. They can be regionally or globally correlatedwith each other. The framework of sequence stratigraphy of the intracratonict basin in thestudy area distinctly differs from that of the passive continental-margin basin in the lack ofdepositional systems of early-middle lowstand, poor development of the deeply incised valleyand condensed section of the maximum sea-flood, good development of type Ⅱ sequenceboundaries and coastal plain depositional systems coexisting with shelf-type fan deltas underwet climatic conditions, Which consequently led to the formation of a paralic lithofacies frame-work. 展开更多
关键词 sequence stratigraphy intracratonic depressional basin framwork model depositional system CARBONIFEROUS
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Chaos game representation walk model for the protein sequences 被引量:3
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作者 高洁 蒋丽丽 徐振源 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4571-4579,共9页
A new chaos game representation of protein sequences based on the detailed hydrophobic-hydrophilic (HP) model has been proposed by Yu et al (Physica A 337(2004) 171). A CGR-walk model is proposed based on the ne... A new chaos game representation of protein sequences based on the detailed hydrophobic-hydrophilic (HP) model has been proposed by Yu et al (Physica A 337(2004) 171). A CGR-walk model is proposed based on the new CGR coordinates for the protein sequences from complete genomes in the present paper. The new CCR coordinates based on the detailed HP model are converted into a time series, and a long-memory ARFIMA(p, d, q) model is introduced into the protein sequence analysis. This model is applied to simulating real CCR-walk sequence data of twelve protein sequences. Remarkably long-range correlations are uncovered in the data and the results obtained from these models are reasonably consistent with those available from the ARFIMA(p, d, q) model. 展开更多
关键词 chaos game representation CGR-walk model protein sequence long-memory ARFIMA(p d q) model autocorrelation function
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Microfacies models and sequence stratigraphic architecture of the Oligocene-Miocene Qom Formation, south of Qom City, Iran 被引量:3
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作者 Mahnaz Amirshahkarami Mahnaz Karavan 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第4期593-604,共12页
The Oligocene-Miocene Qom Formation has different depositional models in the Central han, Sanandaj-Sirjan and Urunlieh-Dokhtar inagmatic arc provinces in han. The Kahak section of the Qom Formation in the Uiumieh-Dokh... The Oligocene-Miocene Qom Formation has different depositional models in the Central han, Sanandaj-Sirjan and Urunlieh-Dokhtar inagmatic arc provinces in han. The Kahak section of the Qom Formation in the Uiumieh-Dokhtar magmatic arc has been studied, in order to determinate its microfacies, depositional model and sequence stratigraphy. The textural analysis and faunal assemblages reveal ten microfacies. These microfacies are indicative of five depositional settings of open marine, patch reef, lagoon, tidal flat and beach of the inner and middle ramp. On the basis of the vertical succession architecture of depositional system tracts, four third-order sequences have been recognized in the Oligocene-Miocene Kahak succession of Qom Formation. Based on the correlation charts, the transgression of the Qom Sea started fiom the southeast and continued gradually towards the north. This resulted in widespread northward development of the lagoon paleoenvironment in the Aquitanian-Burdigalian stages. Also, the sequence stratigraphic model of the Oligocene Miocene Qom Formation has an architecture similar to those that have developed from Oligocene Miocene global sea level changes. 展开更多
关键词 Rupelian-ChattianAquitanian- Burdigalian Paleoenvironment Sedimentary model sequence stratigraphy
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Classification and Facies Sequence Model of Subaqueous Debris Flows 被引量:8
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作者 XIAN Benzhong LIU Jianping +3 位作者 DONG Yanlei LU Zhiyong HE Yanxin WANG Junhui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期751-752,共2页
Objective Debris flows are cohesive sediment gravity flows which occur in both subaerial and subaqueous settings. Compared to subaerial debris flows which have been well studied as a geological hazard, subaqueous deb... Objective Debris flows are cohesive sediment gravity flows which occur in both subaerial and subaqueous settings. Compared to subaerial debris flows which have been well studied as a geological hazard, subaqueous debris flows showing complicated sediment composition and sedimentary processes were poorly understood. The main objective of this work is to establish a classification scheme and facies sequence models of subaqueous debris flows for well understanding their sedimentary processes and depositional characteristics. 展开更多
关键词 Classification and Facies sequence model of Subaqueous Debris Flows
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Integration of Sequence Stratigraphic Analysis and 3D Geostatistical Modeling of Pliocene–Pleistocene Delta,F3 Block,Netherlands 被引量:1
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作者 Haris Ahmed KHAN Ali Asghar SHAHID +3 位作者 Muhammad Jahangir KHAN Taher ZOUAGHI Maria Dolores ALVAREZ Syed Danial Mehdi NAQVI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期256-268,共13页
This research is focused on the analysis of the sequence stratigraphic units of F3 Block,within a wave-dominated delta of Plio–Pleistocene age.Three wells of F3 block and a 3D seismic data,are utilized in this resear... This research is focused on the analysis of the sequence stratigraphic units of F3 Block,within a wave-dominated delta of Plio–Pleistocene age.Three wells of F3 block and a 3D seismic data,are utilized in this research.The conventional techniques of 3D seismic interpretation were utilized to mark the 11 surfaces on the seismic section.Integration of seismic sequence stratigraphic interpretation,using well logs,and subsequent 3D geostatistical modeling,using seismic data,aided to evaluate the shallow hydrocarbon traps.The resulting models were obtained using System Tract and Facies models,which were generated by using sequential stimulation method and their variograms made by spherical method,moreover,these models are validated via histograms.The CDF curve generated from upscaling of well logs using geometric method,shows a good relation with less percentage of errors(1 to 2 for Facies and 3 to 4 for System Tract models)between upscaled and raw data that complements the resulted models.These approaches help us to delineate the best possible reservoir,lateral extent of system tracts(LST and/or HST)in the respective surface,and distribution of sand and shale in the delta.The clinoform break points alteration observed on seismic sections,also validates the sequence stratigraphic interpretation.The GR log-based Facies model and sequence stratigraphy-based System Tract model of SU-04-2 showed the reservoir characteristics,presence of sand bodies and majorly LST,respectively,mainly adjacent to the main fault of the studied area.Moreover,on the seismic section,SU-04-2 exhibits the presence of gas pockets at the same location that also complements the generated Facies and System Tract models.The generated models can be utilized for any similar kind of study and for the further research in the F3 block reservoir characterization. 展开更多
关键词 sequence stratigraphy facies modeling system tract modeling F3 block North Sea
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EXTENSION OF SEQUENCE STRATIGRAPHIC MODELAND SEQUENCE STRATIGRAPHIC ANALYSIS IN LIMNIC DEPOSITIONAL BASIN 被引量:1
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作者 李增学 魏久传 +4 位作者 王民镇 李守春 李青山 金秀昆 兰恒星 《Journal of Coal Science & Engineering(China)》 1996年第2期1-8,共8页
The architectural patterns of sedimentary succession are diverse in different depositionalbasins. The sedimentary architecture and geological condition of such basins asepicontinental sea, intraplate limnic basins, et... The architectural patterns of sedimentary succession are diverse in different depositionalbasins. The sedimentary architecture and geological condition of such basins asepicontinental sea, intraplate limnic basins, etc., differ cIearly from those of continentalmargin basin. Extension, complement and perfection of sequence stratigraphic models are needed in the studies of various depositional basins based on the classical sequence model. This paper, for this reason,expounds the thought, principles of sequence division, methodology and technology of the study of sequence stratigraphy in epicontinental and limnic basins. 展开更多
关键词 epicontinental sea basin limnic basin extension of sedimentary sequence model sequence stratigraphic analysis
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High-Resolution Sequence Stratigraphy and Coal Accumulating Models of the Permo-Carboniferous Coal Measures in Southwestern Shanxi
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作者 Zhenghui Xiao~(1,2),Longyi Shao~2,Hao Wang~2,Jing Lu~2 1.Hunan University of Science and Technology,Xiangtan 411201,China. 2.Department of Resources and Earth Sciences,China University of Mining and Technology(Beijing),Beijing 100083,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期143-144,共2页
The Qinshui Basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China.The methane reservoirs in this area are the Carboniferous and Permian coals and their thic... The Qinshui Basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China.The methane reservoirs in this area are the Carboniferous and Permian coals and their thickness are strongly controlled by the depositional environments and the sequence stratigraphic framework.This paper analyzes the high-resolution sequence stratigraphy of the Permo-Carbo- 展开更多
关键词 sequence STRATIGRAPHIC framework coal-accumulating model PERMO-CARBONIFEROUS Qinshui Basin
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Brief Introduction to Self-Adapting Hidden Markov Model Program for Multiple Sequences Alignment
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作者 GuYan-hong SHIDing-hua 《Journal of Shanghai University(English Edition)》 CAS 2001年第2期93-95,共3页
In this letter, we briefly describe a program of self adapting hidden Markov model (SA HMM) and its application in multiple sequences alignment. Program consists of two stage optimisation algorithm.
关键词 hidden Markov model (HMM) profile HMM multiple sequences alignment BIOINFORMATICS
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Estimation of Partial Linear Error-in-Variables Models under Martingale Difference Sequence
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作者 Zhuoxi YU Dehui WANG Na HUANG 《Journal of Mathematical Research with Applications》 CSCD 2015年第4期463-472,共10页
Consider the partly linear model Y = xβ + g(t) + e where the explanatory x is erroneously measured, and both t and the response Y are measured exactly, the random error e is a martingale difference sequence. Let ... Consider the partly linear model Y = xβ + g(t) + e where the explanatory x is erroneously measured, and both t and the response Y are measured exactly, the random error e is a martingale difference sequence. Let ~ be a surrogate variable observed instead of the true x in the primary survey data. Assume that in addition to the primary data set containing N observations of {(Yj, xj, tj)n+N j=n+1 }, the independent validation data containing n observations of {(xj, x j, tj)n j=1 } is available. In this paper, a semiparametric method with the primary data is employed to obtain the estimator ofβ and g(-) based on the least squares criterion with the help of validation data. The proposed estimators are proved to be strongly consistent. Finite sample behavior of the estimators is investigated via simulations too. 展开更多
关键词 partial linear error-in-variables models martingale difference sequence validationdata strong consistency
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