期刊文献+
共找到922篇文章
< 1 2 47 >
每页显示 20 50 100
Oil-source correlation and Paleozoic source rock analysis in the Siwa Basin,Western Desert:Insights from well-logs,Rock-Eval pyrolysis,and biomarker data
1
作者 Mohamed I.Abdel-Fattah Mohamed Reda +3 位作者 Mohamed Fathy Diaa A.Saadawi Fahad Alshehri Mohamed S.Ahmed 《Energy Geoscience》 EI 2024年第3期313-327,共15页
Understanding the origins of potential source rocks and unraveling the intricate connections between reservoir oils and their source formations in the Siwa Basin(Western Desert,Egypt)necessitate a thorough oil-source ... Understanding the origins of potential source rocks and unraveling the intricate connections between reservoir oils and their source formations in the Siwa Basin(Western Desert,Egypt)necessitate a thorough oil-source correlation investigation.This objective is achieved through a meticulous analysis of well-log responses,Rock-Eval pyrolysis,and biomarker data.The analysis of Total Organic Carbon across 31 samples representing Paleozoic formations in the Siwa A-1X well reveals a spectrum of organic richness ranging from 0.17 wt%to 2.04 wt%,thereby highlighting diverse levels of organic content and the presence of both Type II and Type III kerogen.Examination of the fingerprint characteristics of eight samples from the well suggests that the Dhiffah Formation comprises a blend of terrestrial and marine organic matter.Notably,a significant contribution from more oxidized residual organic matter and gas-prone Type III kerogen is observed.Contrarily,the Desouky and Zeitoun formations exhibit mixed organic matter indicative of a transitional environment,and thus featuring a pronounced marine influence within a more reducing setting,which is associated with Type II kerogen.Through analysis of five oil samples from different wells—SIWA L-1X,SIWA R-3X,SIWA D-1X,PTAH 5X,and PTAH 6X,it is evident that terrestrial organic matter,augmented by considerable marine input,was deposited in an oxidizing environment,and contains Type III kerogen.Geochemical scrutiny confirms the coexistence of mixed terrestrial organic matter within varying redox environments.Noteworthy is the uniformity of identified kerogen Types II and III across all samples,known to have potential for hydrocarbon generation.The discovery presented in this paper unveils captivating prospects concerning the genesis of oil in the Jurassic Safa reservoir,suggesting potential links to Paleozoic sources or even originating from the Safa Member itself.These revelations mark a substantial advancement in understanding source rock dynamics and their intricate relationship with reservoir oils within the Siwa Basin.By illuminating the processes of hydrocarbon genesis in the region,this study significantly enriches our knowledge base. 展开更多
关键词 Biomarker data oil-source correlation rock-Eval pyrolysis Source rocks Siwa Basin
下载PDF
Oil-source rock correlation and quantitative assessment of Ordovician mixed oils in the Tazhong Uplift, Tarim Basin 被引量:11
2
作者 Li Sumei Pang Xiongqi +2 位作者 Zhang Baoshou Xiao Zhongyao Gu Qiaoyuan 《Petroleum Science》 SCIE CAS CSCD 2010年第2期179-191,共13页
The origin of the marine oils in the Tarim Basin has long been a disputed topic. A total of 58 DST (drill stem test) crude oil and 8 rock samples were investigated using a comprehensive geochemical method to charact... The origin of the marine oils in the Tarim Basin has long been a disputed topic. A total of 58 DST (drill stem test) crude oil and 8 rock samples were investigated using a comprehensive geochemical method to characterize and identify the origin of the Ordovician oils in the Tazhong Uplift, Tarim Basin, northwest China. Detailed oil–oil and oil–source rock correlations show that the majority of the oils have typical biomarker characteristics of the Middle-Upper Ordovician (O2+3) source rock and the related crude oil. These characteristics include a distinct "V-shaped" relative abundance of C27, C28 and C29 regular steranes, low abundance of dinosterane, 24-norcholestanes, triaromatic dinosteroids and gammacerane. Only a few oils display typical biomarker characteristics indicating the Cambrian–Lower Ordovician (∈-O1) genetic affinity, such as linear or anti "L" shape distribution of C27, C28 and C29 regular sterane, with relatively high concentrations of dinosterane, 24-norcholestanes, triaromatic dinosteroids and gammacerane. It appears that most of the Ordovician oils in the Tazhong Uplift were derived from the O2+3 intervals, as suggested by previous studies. However, the compound specific n-alkane stable carbon isotope data indicate that the Ordovician oils are mixtures from both the ∈-O1 and O2+3 source rocks rather than from the O2+3 strata alone. It was calculated that the proportion of the∈-O1 genetic affinity oils mixed is about 10.8%-74.1%, with an increasing trend with increasing burial depth. This new oil-mixing model is critical for understanding hydrocarbon generation and accumulation mechanisms in the region, and may have important implications for further hydrocarbon exploration in the Tarim Basin. 展开更多
关键词 BIOMARKER compound specific isotope oil–source rock correlation mixed oil
下载PDF
The geochemical characteristics and oil-source rock correlation of oilshow from the Majiashan profile, Chaoxian County, South of Anhui Province 被引量:4
3
作者 TANG Youjun WEN Zhigang ZAN Ling 《Chinese Journal Of Geochemistry》 EI CAS 2008年第1期53-57,共5页
In the future time the exploration of marine oil and gas will be one of the significant domains in China. In this paper the biomarker assemblage characteristics of oilshow in the Nanlinghu Formation of the Majiashan p... In the future time the exploration of marine oil and gas will be one of the significant domains in China. In this paper the biomarker assemblage characteristics of oilshow in the Nanlinghu Formation of the Majiashan pro- file, which is located in Chaoxian County, south of Anhui Province, are described in the light of gas chromatogra- phy/mass spectrometric (GCMS) analysis on the qualitative and quantitative basis. Based on the investigation of the biomarker assemblage characteristics of possible source rocks developed in the area studied, a conclusion is drawn that the oilshow was generated from the Nanlinghu Formation source rocks (abbreviated as T1n), instead of the Qixia Formation source rocks (abbreviated as P1q). It is pointed out that the T1n is of strong potential for future oil explora- tion, and therefore much attention should be paid to it. 展开更多
关键词 地理特征 岩石 油-水系统 安徽省
下载PDF
Dibenzofuran Series in Terrestrial Source Rocks and Crude Oils and Applications to Oil-Source Rock Correlations in the Kuche Depression of Tarim Basin, NW China 被引量:9
4
作者 李景贵 李梅 王兆云 《Chinese Journal Of Geochemistry》 EI CAS 2004年第2期113-123,共11页
Ten series of aromatic hydrocarbon compounds (biphenyl, naphthalene, phenanthrene, anthracene, retene, chrysene, benzoanthracene, dibenzofuran, fluorene, dibenzothiophene) isolated from seven Triassic and Jurassic lac... Ten series of aromatic hydrocarbon compounds (biphenyl, naphthalene, phenanthrene, anthracene, retene, chrysene, benzoanthracene, dibenzofuran, fluorene, dibenzothiophene) isolated from seven Triassic and Jurassic lacustrine mudstone samples and three swamp coal samples, as well as five crude oil samples collected in the Kuche depression of the Tarim Basin, NW China, have been analysed by GC-MS techniques. It is found that the relative abundances of dibenzofuran series are higher in the three swamp coal samples than those in the lacustrine mudstone samples. Based on the similar relative abundances of dibenzofuran series, especially dibenzofuran compound, in the TICs of aromatic hydrocarbons, crude oils from wells SA3 (K), YTK5 (E, K) and QL1 (E) are thought to have been derived predominantly from the coals of the Lower Jurassic Yangxia Formation or Middle Jurassic Kezilenuer Formation, whereas those from wells YM7 (O) and YH1 (E) were derived mainly from Triassic and Jurassic lacustrine mudstones in the Kuche depression. This is the first report about how to distinguish coal-generated oils from lacustrine mudstone-generated oils in the Kuche depression in terms of the dibenzofuran series. The present paper has enlightening and directive significance for further oil-source rock correlations and oil and/or gas exploration in the Kuche depression of the Tarim Basin. 展开更多
关键词 氧芴 芳烃 三叠纪 侏罗纪 泥岩 油源
下载PDF
Influence of rock property correlation on reliability analysis of rock slope stability: From property characterization to reliability analysis 被引量:8
5
作者 Adeyemi Emman Aladejare Yu Wang 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第6期1639-1648,共10页
Cohesion(c) and friction angle(φ) of rock are important parameters required for reliability analysis of rock slope stability. There is correlation between c and φ which affects results of reliability analysis of roc... Cohesion(c) and friction angle(φ) of rock are important parameters required for reliability analysis of rock slope stability. There is correlation between c and φ which affects results of reliability analysis of rock slope stability. However, the characterization of joint probability distribution of c and φ through which their correlation can be estimated requires a large amount of rock property data, which are often not available for most rock engineering projects. As a result, the correlation between c and φ is often ignored or simply assumed during reliability studies, which may lead to bias estimation of failure probability. In probabilistic rock slope stability analysis, the influence of ignoring or simply assuming the correlation of the rock strength parameters(i.e., c and φ) on the reliability of rock slopes has not been fully investigated. In this study, a Bayesian approach is developed to characterize the correlation between c and φ, and an expanded reliability-based design(RBD) approach is developed to assess the influence of correlation between c and φ on reliability of a rock slope. The Bayesian approach characterizes the sitespecific joint probability distribution of c and φ, and quantifies the correlation between c and φ using available limited data pairs of c and φ from a rock project. The expanded RBD approach uses the joint probability distribution of c and φ obtained through the Bayesian approach as inputs, to determine the reliability of a rock slope. The approach gives insight into the propagation of the correlation between c and φ through their joint probability into the reliability analysis, and their influence on the calculated reliability of the rock slope. The approaches may be applied in practice with little additional effort from a conventional analysis. The proposed approaches are illustrated using real c and φ data pairs obtained from laboratory tests of fractured rock at Forsmark, Sweden. 展开更多
关键词 Reliability-based design rock SLOPE correlation Failure PROBABILITY BAYESIAN approach Joint PROBABILITY distribution
下载PDF
Uniaxial experimental study of the acoustic emission and deformation behavior of composite rock based on 3D digital image correlation(DIC) 被引量:17
6
作者 Jian-Long Cheng Sheng-Qi Yang +3 位作者 Kui Chen Dan Ma Feng-Yuan Li Li-Ming Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第6期999-1021,共23页
In this paper, uniaxial compression tests were carried out on a series of composite rock specimens with different dip angles, which were made from two types of rock-like material with different strength. The acoustic ... In this paper, uniaxial compression tests were carried out on a series of composite rock specimens with different dip angles, which were made from two types of rock-like material with different strength. The acoustic emission technique was used to monitor the acoustic signal characteristics of composite rock specimens during the entire loading process. At the same time, an optical non-contact 3 D digital image correlation technique was used to study the evolution of axial strain field and the maximal strain field before and after the peak strength at different stress levels during the loading process. The effect of bedding plane inclination on the deformation and strength during uniaxial loading was analyzed. The methods of solving the elastic constants of hard and weak rock were described. The damage evolution process, deformation and failure mechanism, and failure mode during uniaxial loading were fully determined. The experimental results show that the θ = 0?–45?specimens had obvious plastic deformation during loading, and the brittleness of the θ = 60?–90?specimens gradually increased during the loading process. When the anisotropic angle θincreased from 0?to 90?, the peak strength, peak strain,and apparent elastic modulus all decreased initially and then increased. The failure mode of the composite rock specimen during uniaxial loading can be divided into three categories:tensile fracture across the discontinuities(θ = 0?–30?), slid-ing failure along the discontinuities(θ = 45?–75?), and tensile-split along the discontinuities(θ = 90?). The axial strain of the weak and hard rock layers in the composite rock specimen during the loading process was significantly different from that of the θ = 0?–45?specimens and was almost the same as that of the θ = 60?–90?specimens. As for the strain localization highlighted in the maximum principal strain field, the θ = 0?–30?specimens appeared in the rock matrix approximately parallel to the loading direction,while in the θ = 45?–90?specimens it appeared at the hard and weak rock layer interface. 展开更多
关键词 Uniaxial compression tests on composite rock ANISOTROPY Elastic constant Failure mode 3D digital image correlation Acoustic emission Strain field
下载PDF
Deformation mechanism of high-stress and broken-expansion surrounding rock and supporting optimization based on the gray correlation theory 被引量:6
7
作者 余伟健 WANG Ping DU Shao-hua 《Journal of Chongqing University》 CAS 2014年第3期99-114,共16页
Aiming at the large deformation and support problems of high-stress and broken-expansion surrounding rock, and taking 1 000 m level roadway of Mine II in Jinchuan as the research object, an investigation on the deform... Aiming at the large deformation and support problems of high-stress and broken-expansion surrounding rock, and taking 1 000 m level roadway of Mine II in Jinchuan as the research object, an investigation on the deformation and damage of roadway surrounding rock and an analysis of its mechanism were carried out. The gray correlation theory was used in support scheme optimization design. First, causes and mechanism of deformation of the 1 000 m horizontal transport channel were analyzed through field investigation, laboratory test and data processing methods. We arguued that poor engineering geological conditions and deep pressure increases were the main factors, and the deformation mechanism was mainly the ground deformation pressure. Second, the gray correlation theory was used to construct supporting optimization decision method in the deep roadway. This method more comprehensively considers various factors, including construction, costs, and supporting material functions. The combined support with pre-stressed anchor cables, shotcrete layer, bolt and metal net was put forward according to the actual roadway engineering characteristics. Finally, 4 support schemes were put forward for new roadways. The gray relational theory was applied to optimizing the supporting method, undertaking technical and economic comparison to obtain the correlation degree, and accordingly the schemes were evaluated. It was concluded as follows: the best was the flexible retaining scheme using the steel strand anchor; the second best was the one using plate anchors on the top and rigid common screw steel bolt on the two sides; the ttiird was; the rigid common screw steel bolt in full section of roadway; and the worst is the planished steel rigid support. The optimized scheme was applied to the 1000 m level of new excavation roadway. The results show that the roadway surrounding rock can reach a stable state after 5 to 6 months monitoring, with a convergence rate less than 1 mm/d. 展开更多
关键词 deep high stress broken-expansion surrounding rock deformation and failure of roadways gray correlation theory
下载PDF
Effective source rock selection and oil–source correlation in the Western Slope of the northern Songliao Basin,China 被引量:2
8
作者 He Bi Peng Li +2 位作者 Yun Jiang Jing-Jing Fan Xiao-Yue Chen 《Petroleum Science》 SCIE CAS CSCD 2021年第2期398-415,共18页
This study considers the Upper Cretaceous Qingshankou Formation,Yaojia Formation,and the first member of the Nenjiang Formation in the Western Slope of the northern Songliao Basin.Dark mudstone with high abundances of... This study considers the Upper Cretaceous Qingshankou Formation,Yaojia Formation,and the first member of the Nenjiang Formation in the Western Slope of the northern Songliao Basin.Dark mudstone with high abundances of organic matter of Gulong and Qijia sags are considered to be significant source rocks in the study area.To evaluate their development characteristics,differences and effectiveness,geochemical parameters are analyzed.One-dimensional basin modeling and hydrocarbon evolution are also applied to discuss the effectiveness of source rocks.Through the biomarker characteristics,the source–source,oil–oil,and oil–source correlations are assessed and the sources of crude oils in different rock units are determined.Based on the results,Gulong and Qijia source rocks have different organic matter primarily detrived from mixed sources and plankton,respectively.Gulong source rock has higher thermal evolution degree than Qijia source rock.The biomarker parameters of the source rocks are compared with 31 crude oil samples.The studied crude oils can be divided into two groups.The oil–source correlations show that group I oils from Qing II–III,Yao I,and Yao II–III members were probably derived from Gulong source rock and that only group II oils from Nen I member were derived from Qijia source rock. 展开更多
关键词 Songliao basin Western slope Source rock distinction Crude oils BIOMARKER oil-source correlation
下载PDF
Microscopic damage evolution of anisotropic rocks under indirect tensile conditions: Insights from acoustic emission and digital image correlation techniques 被引量:2
9
作者 Chaoqun Chu Shunchuan Wu +1 位作者 Chaojun Zhang Yongle Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第9期1680-1691,共12页
The anisotropy induced by rock bedding structures is usually manifested in the mechanical behaviors and failure modes of rocks.Brazilian tests are conducted for seven groups of shale specimens featuring different bedd... The anisotropy induced by rock bedding structures is usually manifested in the mechanical behaviors and failure modes of rocks.Brazilian tests are conducted for seven groups of shale specimens featuring different bedding angles. Acoustic emission (AE) and digital image correlation (DIC) technologies are used to monitor the in-situ failure of the specimens. Furthermore, the crack morphology of damaged samples is observed through scanning electron microscopy (SEM). Results reveal the structural dependence on the tensile mechanical behavior of shales. The shale disk exhibits compression in the early stage of the experiment with varying locations and durations. The location of the compression area moves downward and gradually disappears when the bedding angle increases. The macroscopic failure is well characterized by AE event location results, and the dominant frequency distribution is related to the bedding angle. The b-value is found to be stress-dependent.The crack turning angle between layers and the number of cracks crossing the bedding both increase with the bedding angle, indicating competition between crack propagations. SEM results revealed that the failure modes of the samples can be classified into three types:tensile failure along beddings with shear failure of the matrix, ladder shear failure along beddings with tensile failure of the matrix, and shear failure along multiple beddings with tensile failure of the matrix. 展开更多
关键词 anisotropic rock failure mechanism acoustic emission digital image correlation Brazilian test
下载PDF
Anisotropic creep behavior of soft-hard interbedded rock masses based on 3D printing and digital imaging correlation technology 被引量:2
10
作者 TIAN Yun WU Fa-quan +5 位作者 TIAN Hong-ming LI Zhe SHU Xiao-yun HE Lin-kai HUANG Man CHEN Wei-zhong 《Journal of Mountain Science》 SCIE CSCD 2023年第4期1147-1158,共12页
Three-dimensional(3D)printing technology is increasingly used in experimental research of geotechnical engineering.Compared to other materials,3D layer-by-layer printing specimens are extremely similar to the inherent... Three-dimensional(3D)printing technology is increasingly used in experimental research of geotechnical engineering.Compared to other materials,3D layer-by-layer printing specimens are extremely similar to the inherent properties of natural layered rock masses.In this paper,soft-hard interbedded rock masses with different dip angles were prepared based on 3D printing(3DP)sand core technology.Uniaxial compression creep tests were conducted to investigate its anisotropic creep behavior based on digital imaging correlation(DIC)technology.The results show that the anisotropic creep behavior of the 3DP soft-hard interbedded rock mass is mainly affected by the dip angles of the weak interlayer when the stress is at low levels.As the stress level increases,the effect of creep stress on its creep anisotropy increases significantly,and the dip angle is no longer the main factor.The minimum value of the long-term strength and creep failure strength always appears in the weak interlayer within 30°–60°,which explains why the failure of the layered rock mass is controlled by the weak interlayer and generally emerges at 45°.The tests results are verified by comparing with theoretical and other published studies.The feasibility of the 3DP soft-hard interbedded rock mass provides broad prospects and application values for 3DP technology in future experimental research. 展开更多
关键词 3D printing Soft-hard interbedded rock mass Digital imaging correlation technology Weak interlayer Anisotropic creep
下载PDF
Application of gray correlation analysis and artificial neural network in rock mass blasting 被引量:2
11
作者 朱红兵 吴亮 《Journal of Coal Science & Engineering(China)》 2005年第1期44-47,共4页
Studied forecasting and controlling the blasting fragmentation by using artifi- cial neural network for multi-ingredients. At the same time, according to the characteris- tic of multi-parameters input to network model... Studied forecasting and controlling the blasting fragmentation by using artifi- cial neural network for multi-ingredients. At the same time, according to the characteris- tic of multi-parameters input to network model, the gray correlation theory was employed to find out key factors, which can not only save time of computation and parameters in- put, but improve the stability of the model. 展开更多
关键词 gray correlation analysis neural network rock mass blasting
下载PDF
Petroleum in the Jurassic Reservoirs within the Eastern Fukang Sub-depression,Junggar Basin,NW China:Correlation and Source Rock
12
作者 CHENG Bin LIU Hua +3 位作者 ZHANG Kuihua REN Xincheng MENG Xiangyu LIU Dezhi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第3期777-795,共19页
The origin and source of the petroleum in the Jurassic reservoirs within the eastern Fukang sub-depression were geochemically investigated.They show thermal maturities matching the peak generation stage,while the cond... The origin and source of the petroleum in the Jurassic reservoirs within the eastern Fukang sub-depression were geochemically investigated.They show thermal maturities matching the peak generation stage,while the condensates are at the early stage of intense cracking.Oils and condensates may have experienced mild evaporative fractionation,while mixing of severely biodegraded with non-biodegraded oils has occurred.Using biomarkers and isotopes,petroleums were classified into GroupⅠ,ⅡandⅢgenetic groups,with GroupⅢfurther divided intoⅢa andⅢb subgroups.GroupⅠpetroleum displays heavy carbon isotopes,a strong predominance of pristine over phytane,high C_(19)and C_(20)tricyclic and C_(24)tetracyclic terpanes,low gammacerane,and dominant C_(29)steranes,while GroupⅡshows light carbon isotopes,a predominance of phytane over pristine,high C_(21)and C_(23)tricyclic with low C_(24)tetracyclic terpanes,high gammacerane and dominant C_(27)steranes.GroupⅢa petroleum shows mixing compositions of GroupⅠandⅡ,while GroupⅢb displays similar compositions to Group I,but with significantly higher Ts,C_(29)Ts and C_(30)diahopane proportions.Oil-source rock correlation suggests GroupⅠandⅡpetroleums originate from Jurassic and Permian source rocks,respectively,while GroupⅢa are mixtures sourced from these rocks andⅢb are mixtures from Jurassic and Triassic source rocks. 展开更多
关键词 biomarkers oil-source rock correlation Jurassic reservoirs Fukang sub-depression Junggar Basin
下载PDF
Deformation Field around the Stress Induced Crack Area in Sandstone by the Digital Speckle Correlation Method 被引量:4
13
作者 ZHAO Yonghong MA Shaopeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期661-672,共12页
The deformation field around sub-cracks was calculated using the digital speckle correlation method. First, the uni-axial compression tests on sandstone samples containing a pre- fabricated fracture were made. Photomi... The deformation field around sub-cracks was calculated using the digital speckle correlation method. First, the uni-axial compression tests on sandstone samples containing a pre- fabricated fracture were made. Photomicrographs showing the characteristics of the sub-crack development were taken using a scanning electron microscope (SEM). From these photomicrographs, the real-time images showing the initiation, growth and coalescence of sub-cracks and micro-cracks in the sandstone specimens were obtained and the effects of loading level as well as grain boundaries on the development of cracks were analyzed. Second, the intensity images of the sandstone specimen surface were captured from the observations of the SEM corresponding to different loading levels. Then correlation computation was carried out for the sequential pairs of intensity images to evaluate the displacement components, as well as the strain field. The results show that the deformation varies in different areas separated by sub-cracks during rock damage processes. 展开更多
关键词 SANDSTONE sub-crack in rock scanning electron microscopy observation displacementfield digital speckle correlation method rock mechanics
下载PDF
Stratigraphic Correlation And Division of the Salite Strata 被引量:1
14
作者 WANG Hao YIN Taiju WANG Shu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期138-139,共2页
1 Introduction Stratigraphic correlation is the most important basic work in oil and gas exploration and development,Scientific and reasonable stratigraphic correlation is the premise of developing fine reservoir desc... 1 Introduction Stratigraphic correlation is the most important basic work in oil and gas exploration and development,Scientific and reasonable stratigraphic correlation is the premise of developing fine reservoir description,and it is 展开更多
关键词 In Stratigraphic correlation And Division of the Salite Strata rock
下载PDF
Time difference correlation between earthquake lights and seismic ground accelerations
15
作者 Juan Antonio Lira Maurizio Mulas 《Applied Geophysics》 SCIE CSCD 2021年第1期9-16,128,共9页
Although earthquake lights have been known since ancient times,it has not been easy to study them.It was not until the 60s that the first photographs of them were taken.During the Peruvian earthquake in 2007,it was po... Although earthquake lights have been known since ancient times,it has not been easy to study them.It was not until the 60s that the first photographs of them were taken.During the Peruvian earthquake in 2007,it was possible to obtain the fi rst fi lm recording on earthquake lights.Likewise,during the earthquakes in Ecuador in 2016 and in Mexico in 2017,two fi lms of the earthquake lights were recorded.These fi lm recordings have helped in the study of earthquake lights,both for their objectivity and for their informational content.Several causal mechanisms have been proposed to explain earthquake lights:piezoelectricity,radon emanation,fluid diffusion,friction-vaporization,positive holes and dipole currents,among others.In this work a time difference correlation between earthquake lights and seismic ground accelerations was found and we use both seismic data and fi lm recordings of earthquake lights to explain its origin.In the discussion section it is suggested that fracturing of rocks manifest itself to some extent in the form of static electricity producing earthquake lights through induction The induction model proposed is new and it can explain the formation of EQL,even if the earth’s crust has layers of large electrical resistivity.The model also explains the formation of seismic lights without the need for special conditions on the earth’s surface or in the atmosphere.A better understanding of the earthquake lights generation process can improve our understanding of seismicity and help in the prediction of earthquakes. 展开更多
关键词 time diff erence correlation earthquake lights seismic ground accelerations rock fracturing
下载PDF
Roughness characterization and shearing dislocation failure for rock-backfill interface
16
作者 Meifeng Cai Zhilou Feng +3 位作者 Qifeng Guo Xiong Yin Minghui Ma Xun Xi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1167-1176,共10页
Shearing dislocation is a common failure type for rock–backfill interfaces because of backfill sedimentation and rock strata movement in backfill mining goaf.This paper designed a test method for rock–backfill shear... Shearing dislocation is a common failure type for rock–backfill interfaces because of backfill sedimentation and rock strata movement in backfill mining goaf.This paper designed a test method for rock–backfill shearing dislocation.Using digital image techno-logy and three-dimensional(3D)laser morphology scanning techniques,a set of 3D models with rough joint surfaces was established.Further,the mechanical behavior of rock–backfill shearing dislocation was investigated using a direct shear test.The effects of interface roughness on the shear–displacement curve and failure characteristics of rock–backfill specimens were considered.The 3D fractal dimen-sion,profile line joint roughness coefficient(JRC),profile line two-dimensional fractal dimension,and the surface curvature of the frac-tures were obtained.The correlation characterization of surface roughness was then analyzed,and the shear strength could be measured and calculated using JRC.The results showed the following:there were three failure threshold value points in rock–backfill shearing dis-location:30%–50%displacement before the peak,70%–90%displacement before the peak,and 100%displacement before the peak to post-peak,which could be a sign for rock–backfill shearing dislocation failure.The surface JRC could be used to judge the rock–backfill shearing dislocation failure,including post-peak sliding,uniform variations,and gradient change,corresponding to rock–backfill disloca-tion failure on the field site.The research reveals the damage mechanism for rock–backfill complexes based on the free joint surface,fills the gap of existing shearing theoretical systems for isomerism complexes,and provides a theoretical basis for the prevention and control of possible disasters in backfill mining. 展开更多
关键词 rock–backfill ROUGHNESS correlation characterization shearing dislocation interface failure
下载PDF
A Novel ISSA–DELM Model for Predicting Rock Mass Permeability
17
作者 Chen Xing Leihua Yao Yingdong Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2825-2848,共24页
In pumped storage projects,the permeability of rock masses is a crucial parameter in engineering design and construction.The rock mass permeability coefficient(K)is influenced by various geological parameters,and prev... In pumped storage projects,the permeability of rock masses is a crucial parameter in engineering design and construction.The rock mass permeability coefficient(K)is influenced by various geological parameters,and previous studies aimed to establish an accurate relationship between K and geological parameters.This study uses the improved sparrow search algorithm(ISSA)to optimize the parameter settings of the deep extreme learning machine(DELM),constructing a prediction model with flexible parameter selection and high accuracy.First,the Spearman method is applied to analyze the correlation between geological parameters.A sample database is built by comprehensively selecting four geological indexes:burial depth,rock quality designation(RQD),fracture density characteristic index(FD),and rock mass integrity designation(RID).Hence,the defects of the sparrow search algorithm(SSA)are enhanced using the improved strategy,and the initial input weights of the DELM are optimized.Finally,the proposed ISSA–DELM model is employed to predict the permeability coefficient of rock mass in the entire study area.The results showed that the predictive performance of the model is superior to that of the DELM and SSA–DELM.Therefore,this model successfully provides insights into the distribution characteristics of rock mass permeability at engineering sites. 展开更多
关键词 ISSA DELM rock mass permeability coefficient geological parameter correlation analysis
下载PDF
A novel indirect optical method for rock stress measurement using microdeformation field analysis
18
作者 Yujie Feng Peng-Zhi Pan +2 位作者 Zhaofeng Wang Xufeng Liu Shuting Miao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3616-3628,共13页
Stress measurement plays a crucial role in geomechanics and rock engineering,especially for the design and construction of large-scale rock projects.This paper presents a novel method,based on the traditional stress r... Stress measurement plays a crucial role in geomechanics and rock engineering,especially for the design and construction of large-scale rock projects.This paper presents a novel method,based on the traditional stress relief approach,for indirectly measuring rock stress using optical techniques.The proposed method allows for the acquisition of full-field strain evolution on the borehole’s inner wall before and after disturbance,facilitating the determination of three-dimensional(3D)stress information at multiple points within a single borehole.The study focuses on presenting the method’s theoretical framework,laboratory validation results,and equipment design conception.The theoretical framework comprises three key components:the optical imaging method of the borehole wall,the digital image correlation(DIC)method,and the stress calculation procedure.Laboratory validation tests investigate strain field distribution on the borehole wall under varying stress conditions,with stress results derived from DIC strain data.Remarkably,the optical method demonstrates better measurement accuracy during the unloading stage compared to conventional strain gauge methods.At relatively high stress levels,the optical method demonstrates a relative error of less than 7%and an absolute error within 0.5 MPa.Furthermore,a comparative analysis between the optical method and the conventional contact resistance strain gauge method highlights the optical method’s enhanced accuracy and stability,particularly during the unloading stage.The proposed optical stress measurement device represents a pioneering effort in the application of DIC technology to rock engineering,highlighting its potential to advance stress measurement techniques in the field. 展开更多
关键词 rock stress measurement Optical technology Digital image correlation(DIC)technology Micro-deformation field
下载PDF
Wmic-GMTS and Wmic-GMERR criteria for micron-scale crack propagation in red-bed soft rocks under hydraulic action
19
作者 Guangjun Cui Chunhui Lan +2 位作者 Cuiying Zhou Zhen Liu Chang Xia 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3641-3660,共20页
Micron-scale crack propagation in red-bed soft rocks under hydraulic action is a common cause of engineering disasters due to damage to the hard rockesoft rockewater interface.Previous studies have not provided a theo... Micron-scale crack propagation in red-bed soft rocks under hydraulic action is a common cause of engineering disasters due to damage to the hard rockesoft rockewater interface.Previous studies have not provided a theoretical analysis of the length,inclination angle,and propagation angle of micron-scale cracks,nor have they established appropriate criteria to describe the crack propagation process.The propagation mechanism of micron-scale cracks in red-bed soft rocks under hydraulic action is not yet fully understood,which makes it challenging to prevent engineering disasters in these types of rocks.To address this issue,we have used the existing generalized maximum tangential stress(GMTS)and generalized maximum energy release rate(GMERR)criteria as the basis and introduced parameters related to micron-scale crack propagation and water action.The GMTS and GMERR criteria for micronscale crack propagation in red-bed soft rocks under hydraulic action(abbreviated as the Wmic-GMTS and Wmic-GMERR criteria,respectively)were established to evaluate micron-scale crack propagation in redbed soft rocks under hydraulic action.The influence of the parameters was also described.The process of micron-scale crack propagation under hydraulic action was monitored using uniaxial compression tests(UCTs)based on digital image correlation(DIC)technology.The study analyzed the length,propagation and inclination angles,and mechanical parameters of micron-scale crack propagation to confirm the reliability of the established criteria.The findings suggest that the Wmic-GMTS and Wmic-GMERR criteria are effective in describing the micron-scale crack propagation in red-bed soft rocks under hydraulic action.This study discusses the mechanism of micron-scale crack propagation and its effect on engineering disasters under hydraulic action.It covers topics such as the internal-external weakening of nano-scale particles,lateral propagation of micron-scale cracks,weakening of the mechanical properties of millimeter-scale soft rocks,and resulting interface damage at the engineering scale.The study provides a theoretical basis for the mechanism of disasters in red-bed soft-rock engineering under hydraulic action. 展开更多
关键词 Red-bed soft rocks Hydraulic action Micron-scale cracks Generalized maximum tangential stress (GMTS)criterion Generalized maximum energy release rate (GMERR)criterion Digital image correlation(DIC)
下载PDF
Rho/ROCK信号通路与脑动脉硬化患者血液流变学的相关性研究 被引量:9
20
作者 许忠波 杜婷婷 +1 位作者 冯欣 金桂林 《中国动脉硬化杂志》 CAS 2019年第1期51-54,共4页
目的探讨Rho/ROCK信号通路与脑动脉硬化(CAS)患者血液流变学之间的关系。方法选择CAS患者80例及健康体检者80例,收集血液样本,检测相应生物化学指标、Ras同族体基因家族成员A(RhoA)、Rho激酶2(ROCK2)水平及血细胞比容、全血表观黏度(高... 目的探讨Rho/ROCK信号通路与脑动脉硬化(CAS)患者血液流变学之间的关系。方法选择CAS患者80例及健康体检者80例,收集血液样本,检测相应生物化学指标、Ras同族体基因家族成员A(RhoA)、Rho激酶2(ROCK2)水平及血细胞比容、全血表观黏度(高切、低切)、血浆黏度。比较2组血液流变学指标、RhoA、ROCK2水平;分析CAS患者RhoA、ROCK2水平与血液流变学指标的相关性。结果 CAS组吸烟比例、体质指数、空腹血糖、餐后2 h血糖、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、甘油三酯、血清同型半胱氨酸均高于对照组(P<0.05)。CAS组血细胞比容、全血表观黏度(高切、低切)、血浆黏度、ROCK2、RhoA水平均高于对照组(P <0.05)。Pearson相关分析及多重线性回归分析显示,ROCK2水平与血细胞比容、全血表观黏度高切、低切、血浆黏度呈正相关; RhoA水平与全血表观黏度(高切、低切)呈正相关。结论 Rho/ROCK信号通路与CAS患者血液流变学的异常密切相关,可能参与了CAS的发生发展。 展开更多
关键词 RHO/rock信号通路 脑动脉硬化 血液流变学 相关性
下载PDF
上一页 1 2 47 下一页 到第
使用帮助 返回顶部