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Percutaneous microwave ablation and transcatheter arterial chemoembolization for serum tumor markers and prognostics of middle-late primary hepatic carcinoma 被引量:1
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作者 Zhi-Peng Lin Da-Bei Huang +3 位作者 Xu-Gong Zou Yuan Chen Xiao-Qun Li Jian Zhang 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第12期2783-2791,共9页
BACKGROUND Primary hepatic carcinoma(PHC)has an insidious onset and is usually diagnosed in the middle and late stages.Although transcatheter arterial chemoembolization(TACE)is the preferred option for treating middle... BACKGROUND Primary hepatic carcinoma(PHC)has an insidious onset and is usually diagnosed in the middle and late stages.Although transcatheter arterial chemoembolization(TACE)is the preferred option for treating middle-and advanced-stage PHC,it has limited efficacy in killing tumor cells and poor long-term efficacy.TACE plus percutaneous microwave coagulation therapy(PMCT)is more effective than interventional therapy alone and can improve survival time.However,there are few reports on the effects of TACE and PMCT on serum marker levels and the prognosis of patients with advanced PHC.AIM To investigate the effect of PMCT+TACE on serum tumor markers and the prognosis of middle-late PHC.METHODS This retrospective study included 150 patients with middle-late PHC admitted to Zhongshan People’s Hospital between March 2018 and February 2021.Patients were divided into a single group(treated with TACE,n=75)and a combined group(treated with TACE+PMCT,n=75).Before and after treatment,the clinical efficacy and serum tumor marker levels[carbohydrate antigen 19-9(CA19-9),alpha-fetoprotein(AFP),and carcinoembryonic antigen(CEA)]of both groups were observed.The 1-year survival rates and prognostic factors of the two groups were analyzed.RESULTS The combined group had 21 and 35 cases of complete remission(CR)and partial remission(PR),respectively.The single group had 13 and 25 cases of CR and PR,decreased,with the decrease in the combined group being more significant(P<0.05).The 1-year survival rate of the combined group(80.00%)was higher than that of the single group(60.00%)(P<0.05).The average survival time within 1 year in the combined group was 299.38±61.13 d,longer than that in the single group(214.41±72.97 d,P<0.05).COX analysis revealed that tumor diameter,tumor number,and the treatment method were prognostic factors for patients with middle-late PHC(P<0.05).CONCLUSION TACE+PMCT is effective in treating patients with mid-late PHC.It reduces the levels of tumor markers,prolongs survival,and improves prognosis. 展开更多
关键词 middle-late primary hepatic carcinoma Percutaneous microwave coagulation therapy Transcatheter arterial chemoembolization Effect Tumor markers Prognosis SURVIVAL
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An Updated Review of the Middle-Late Jurassic Yanliao Biota: Chronology,Taphonomy,Paleontology and Paleoecology 被引量:7
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作者 XU Xing ZHOU Zhonghe +2 位作者 Corwin SULLIVAN WANG Yuan REN Dong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2229-2243,共15页
The northeastern Chinese Yanliao Biota (sometimes called the Daohugou Biota) comprises numerous, frequently spectacular fossils of non-marine organisms, occurring in Middle-Upper Jurassic strata in western Liaoning,... The northeastern Chinese Yanliao Biota (sometimes called the Daohugou Biota) comprises numerous, frequently spectacular fossils of non-marine organisms, occurring in Middle-Upper Jurassic strata in western Liaoning, northern Hebei, and southeastern Inner Mongolia. The biota lasted for about 10 million years, divided into two phases: the Bathonian-Callovian Daohugou phase (about 168-164 million years ago) and the Oxfordian Linglongta phase (164-159 million years ago). The Yanliao fossils are often taphonomically exceptional (many vertebrate skeletons, for example, are complete and accompanied by preserved integumentary features), and not only are taxonomically diverse but also include the oldest known representatives of many groups of plants, invertebrates, and vertebrates. These fossils have provided significant new information regarding the origins and early evolution of such clades as fleas, birds, and mammals, in addition to the evolution of some major biological structures such as feathers, and have demonstrated the existence of a complex terrestrial ecosystem in northeast China around the time of the Middle-Late Jurassic boundary. 展开更多
关键词 Yanliao Biota Daohugou phase Linglongta phase middle-late Jurassic Yanliao area
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Field Efficacy Trial and Optimum Control Period of Rice False Smut(Ustilaginoidea virens) in Single Cropping Middle-late Rice 被引量:2
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作者 Liu Huaizhen Li Kanghuo +5 位作者 Huang Qing Lu Xiuming Zhang Bin Li Huifeng Zou Jixiang Zhou Shaochuan 《Plant Diseases and Pests》 CAS 2014年第2期31-34,共4页
[Objective]The paper was to study optimum chemical agents and control periods against rice false smut( Ustilaginoidea virens) in single cropping middle-late rice. [Method]Taking chemical agents( triadimefon,armure,Jin... [Objective]The paper was to study optimum chemical agents and control periods against rice false smut( Ustilaginoidea virens) in single cropping middle-late rice. [Method]Taking chemical agents( triadimefon,armure,Jinggangmycin) as main treatments and spraying periods( within 7 d before initial heading stage,within 7 d before initial heading stage + initial heading stage,initial heading stage) as assisted treatments,the field efficacy trial and optimum control period of U. virens in single cropping middle-late rice were studied using Huanghuazhan and Jinnongsimiao as experimental materials in 2013. [Result] Three chemical agents,triadimefon,armure,Jinggangmycin,extremely reduced diseased panicle rate and disease index of U. virens,but there was no significant difference among three chemical agents. Spraying period did not have significant impact on diseased panicle rate and disease index of U. virens,whereas spraying within7 d before initial heading stage and during initial heading stage had relatively good control effect. Yield increased significantly after application of three chemical agents,and armure led to greater increase. The reason for yield increase was that seed setting rate was significantly increased,and the number of filled grains per panicle was significantly increased. Although spraying period influenced yield,the difference was not significant. [Conclusion] Triadimefon,armure and Jinggangmycin had good control effects against U. virens in single cropping middle-late rice,of which armure had better control effects. Spraying chemical agents increased seed setting rate,and further increased the number of filled grains per panicle and yield. Spraying within 7 d before initial heading stage and during initial heading stage had relatively better control effect against U. virens. 展开更多
关键词 Single cropping middle-late rice Ustilaginoidea virens Field efficacy test
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The Shishugou Fauna of the Middle-Late Jurassic Transition Period in the Junggar Basin of Western China 被引量:1
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作者 XU Xing James M.CLARK +1 位作者 David A.EBERTH Philip J.CURRIE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第4期1115-1135,共21页
The Middle-Late Jurassic transition period is a critical period for the evolution of terrestrial vertebrates,but the global fossil record from this time is relatively poor.The Shishugou Fauna of this period has recent... The Middle-Late Jurassic transition period is a critical period for the evolution of terrestrial vertebrates,but the global fossil record from this time is relatively poor.The Shishugou Fauna of this period has recently produced significant fossil remains of dinosaurs and other vertebrate groups,some representing the earliest known members of several dinosaurian groups and other vertebrate groups and some representing the best-known specimens of their group.These discoveries are significant for our understanding of the origin and evolution of several vertebrate lineages.Radiometric dating indicates that the fauna is aged approximately 159-164 Ma.Comparisons with other similarly-aged terrestrial faunas such as Shaximiao and Yanliao show both taxonomic similarities and differences between these faunas and indicate that the Junggar deposits might have preserved the most complete vertebrate fossil record for a Middle-Late Jurassic Laurasian terrestrial fauna. 展开更多
关键词 middle-late Jurassic Shishugou Fauna Shishugou Formation terrestrial ecosystem Shaximiao Yanliao Junggar Basin
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桑托斯盆地L区块早白垩世Aptian期火山喷发旋回特征与Itapema组介壳灰岩沉积
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作者 赵健 赵俊峰 +4 位作者 任康绪 王红平 王朝锋 阳孝法 杨柳 《地质学报》 EI CAS CSCD 北大核心 2023年第2期539-552,共14页
桑托斯盆地裂陷初期岩浆活动与储层发育关系密切。本文以盆地L区块火成岩-介壳灰岩复合体为研究对象,通过对火成岩岩石学、年代学测试及钻井、测井资料分析等,首次明确了桑托斯盆地裂陷初期岩浆活动特征及其对介壳灰岩沉积过程的控制,... 桑托斯盆地裂陷初期岩浆活动与储层发育关系密切。本文以盆地L区块火成岩-介壳灰岩复合体为研究对象,通过对火成岩岩石学、年代学测试及钻井、测井资料分析等,首次明确了桑托斯盆地裂陷初期岩浆活动特征及其对介壳灰岩沉积过程的控制,并指出介壳灰岩储层的分布特征。L区块内火成岩分属晚白垩世Santonian期—Campanian期和早白垩世Aptian两期岩浆活动产物,并以Aptian期为主,至少经历了7次不连续喷发和3次侵入过程,形成了块状玄武岩、杏仁状玄武岩和玻基斑状玄武岩(含再沉积玻基斑状玄武岩)等喷发相火成岩和以辉绿岩(局部属粗玄岩)、煌斑岩形式产出的侵入相火成岩。Aptian期岩浆多期活动重塑了古地貌,形成了局部构造凸起,促成并控制了下白垩统Itapema组至少6期介壳灰岩沉积,最终形成了~620 m厚火成岩-介壳灰岩复合体。介壳灰岩储层呈透镜体形状,以“散点式”不连续分布在Aptian期盆内古隆、古断阶(坡)等区域,横向连续性差,垂向连通性受限,其发育规模和质量受古地貌及水深条件等影响。 展开更多
关键词 桑托斯盆地 L区块 早白垩世aptian期岩浆 岩浆活动期次 火山喷发旋回 介壳灰岩储层
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Analysis of Sedimentary Environment and Sequence Stratigraphy of Middle-Late Permian Sediments in Coastal Fars, Iran (Zireh Gas Field, Well ZH-A)
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作者 Nasser Rezavand Davood Jahani Hossein Asilian 《Open Journal of Geology》 2016年第12期1539-1552,共14页
The current paper is focused on the facies, sedimentary environment and depositional cycles study of the Middle-Late Permian sediments in the South Fars Zireh Gas Field, the subsurface section of well ZH-A. Four hundr... The current paper is focused on the facies, sedimentary environment and depositional cycles study of the Middle-Late Permian sediments in the South Fars Zireh Gas Field, the subsurface section of well ZH-A. Four hundred thin-sections obtained from cores and cuttings were examined under standard petrographic microscope. For this study research, Corel Draw X6, Corel Photo-Paint, DN2 Microscopy Image Processing System, Scope Photo, Autodesk Map, Geocalc and Auto Cad 2014 were utilized. Based on microfacies analysis and significant founa and flora, fourteen major facies in four facies associations comprising tidal flat (A), lagoon (B), shoal (C) and open marine (D) identified in the well ZH-A. This formation was deposited in inner part of a homoclinal ramp. Based on depositional cycles, seven main 3rd order sequences were revealed in the Well ZH-A. The ooid grainstone facies with interparticle and oomoldic porosity has high reservoir potential. The diagenetic processes like dolomitization and dissolution have significant effect in the reservoir quality. Based on research results, a major framework can be weaved and used to correlate reservoir layering. 展开更多
关键词 middle-late Permian Sediments Depositional Cycles Homoclinal Ramp
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Geochemistry of the Aptian bituminous limestones in Gümuü?hane area,Eastern Black Sea region:new insight into paleogeography and paleoclimate conditions
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作者 Merve Ozyurt 《Acta Geochimica》 EI CAS CSCD 2023年第6期971-987,共17页
Aptian is characterized by widespread deposition of organic-rich sediment.The Aptian bitumen limestone horizon,which is thin decimetre-thick sequences,locally crops out in the Kircaova area,Eastern Black Sea Region(Ea... Aptian is characterized by widespread deposition of organic-rich sediment.The Aptian bitumen limestone horizon,which is thin decimetre-thick sequences,locally crops out in the Kircaova area,Eastern Black Sea Region(Eastern Pontides).They are well correlated with Aptian bitumen limestone in the other Tethys Reams.They are proposed as episodes of increased organic matter.However,background factors controlling organic matter enrichment are poorly known.In this study,we present new inorganic geochemistry,including trace elements,rare earth elements(REE),redox-sensitive elements(RSE),stable-isotopes(δ~(18)O andδ~(13)C),and total organic carbon(TOC).We integrated new geochemical data with existing stratigraphy,paleontology,and organic chemistry data to provide new insight into the depositional environment and paleoclimate conditions during Aptian.The lacustrine bitumen limestone(LBL)samples have variedδ~(13)C(ave.-1.45‰)andδ~(18)O(ave.-4.50‰).They possess distinct REE patterns,with an average of REE(ave.14.45 ppm)and Y/Ho(ave.35)ratios.In addition,they have variable Nd/YbN(0.28-0.81;ave.0.56)and Ce/Ce*(0.68-0.97;ave.0.86),and relatively high Eu^(*)/Eu(1.23-1.53;ave.1.35).They display seawater signatures with reduced oxygen conditions.The enrichment in RSE(Mo,Cu,Ni,and Zn)and the low Mo/TOC(0.70-3.69;ave.2.41)support a certain degree of water restriction.The high Sr/Ba,Sr/Cu,Ga/Rb,and K/Al records of the LBL facies suggest hot house climatic conditions.The sedimentary environment was probably an isolated basin that is transformed from the marine basin.In addition to depositional conditions,the regional parameters such as the climate,increased run-off period,nutrient levels,alkalinity level,and dominant carbonate producers favored the enrichment in organic matter of LBL facies.Thus,extreme greenhouse palaeoclimate conditions have an important role in organic matter enrichment in the isolated basin.Our results are conformable with the published data from marine,semi-restricted basin,and lacustrine settings in the different parts of the Tethys margin.Thus,this approach provides the first insight into the Aptian greenhouse paleo-climate conditions of the Eastern Black Sea Region,NE Turkey. 展开更多
关键词 aptian PALEOCLIMATE Sedimentary conditions GEOCHEMISTRY REE C and O isotopes Limestone Eastern Black Sea
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Sequence stratigraphy of the petroliferous Dariyan Formation (Aptian) in Qeshm Island and offshore (southern Iran) 被引量:2
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作者 P.Mansouri-Daneshvar R.Moussavi-Harami +2 位作者 A.Mahboubi M.H.M.Gharaie A.Feizie 《Petroleum Science》 SCIE CAS CSCD 2015年第2期232-251,共20页
After sea level rises during the Early Cretaceous, upper parts of the Khami Group sediments (Fahliyan, Gadvan, and Dariyan Formations) deposited over Jurassic sediments. The Lower Cretaceous (Aptian) Dariyan Forma... After sea level rises during the Early Cretaceous, upper parts of the Khami Group sediments (Fahliyan, Gadvan, and Dariyan Formations) deposited over Jurassic sediments. The Lower Cretaceous (Aptian) Dariyan Formation (equivalent to the Shu'aiba Formation and Hawar Member of the Arabian Plate) carbonates, which have hydrocarbon reservoir potential, form the uppermost portion of the Khami Group that unconformably overlays the Gadvan Formation and was unconformably covered by the Kazhdumi Formation and Burgan sandstones. Detailed paleontological, sedimentological, and well log analysis were performed on seven wells from Qeshm Island and offshore in order to analyze the sequence stratigraphy of this interval and correlate with other studies of the Dariyan Formation in this region. According to this study, the Dariyan Formation contains 14 carbonate lithofacies, which deposited on a ramp system that deepened in both directions (NE-wells 5, 6 and SWIwells 1, 2). Sequence stratigraphy led to recognition of 5 Aptian third-order sequences toward the Bab Basin (SW-well 1) and 4 Aptian third-order sequences toward Qeshm Island (NE-wells 5 and 6) so these areas show higher gamma on the gamma ray logs and probably have higher source rock potential. Other wells (wells 2-4 and 7) mainly deposited in shallower ramp systems and contain 3 Aptian third-order sequences. On the other hand, rudstone and boundstone lithofacies of studied wells have higher reservoir potential and were deposited during Apt 3 and Apt 4 sequences of the Arabian Plate. The Dariyan Formation in Qeshm Island (well 6) and adjacent well (well 5) was deposited in an intrashelf basin that should be classified as a new intrashelf basin in future Aptian paleogeographic maps. We interpret that salt-related differential subsidence, crustal warping, and reactivation of basement faults of the Arabian Plate boundary were responsible for the creation of the intrashelf basin in the Qeshm area. 展开更多
关键词 Arabian Plate Sequence stratigraphy -Qeshm Island - aptian and Dariyan formation
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Aptian综合年代地层事件:定量地层学的运用(英文) 被引量:1
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作者 Robert W. SCOTT 《地学前缘》 EI CAS CSCD 北大核心 2005年第2期22-30,共9页
以往发表的年代地层数据都是以Ma形式出现,以关键物种的首现面和末现面来界定的.一般而言,这些年龄是在用某种方法确定的某两个层的年龄基础上通过插值获得的,很大程度上仍然是估计值,而不是可以检验的科学结论.我们需要的是一个可以评... 以往发表的年代地层数据都是以Ma形式出现,以关键物种的首现面和末现面来界定的.一般而言,这些年龄是在用某种方法确定的某两个层的年龄基础上通过插值获得的,很大程度上仍然是估计值,而不是可以检验的科学结论.我们需要的是一个可以评价的、剖面重现的、标本重现的而且插值方法是经过严格检验的数据库.图形对比技术正是一个有用的方法,它可以综合众多剖面的分散分布的事件,并可以验证这些事件的顺序和年代.图形对比技术是一个定量的、非统计的方法,可以判别两个剖面之间存在的同时代关系.物种时限和非生物事件投点到X/Y图解上,时限可以通过对比线综合到单个的时间尺度上.其他剖面的数据通过重复以上过程把每个剖面的数据综合进来.获得的时限通过评价有这些物种出现的图形解而得到验证.Aptian阶(约124~112 Ma)时期环境发生巨大变化,用来确定Aptian阶的许多关键生物事件和年代地层事件并不都出现在同一个剖面.因此,这些事件的相对年龄始终是不确定的,也不是相关的.两个事件被提出来用于界定Aptian阶的底界,包括菊石Deshayesites tuarkyricus和磁极性带CM0.然而这两个事件标准地层剖面相隔600 km. 图形对比显示这两次事件出现在7万年间隔内.通过这一方法,来自23条Barremian-Aptian-Albian 期间的剖面被综合进入精确的数据库,可以用来评价和验证来自新剖面的数据. 展开更多
关键词 综合年代地层 定量地层学 aptian
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The Key Role of Aptian-Albian Marine Fossils from Eastern Heilongjiang in Marine-Nonmarine Stratigraphic Correlation 被引量:2
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作者 Gang Li Peter Bengtson 《Open Journal of Geology》 2019年第10期543-546,共4页
The alternating marine and nonmarine coal-bearing Lower Cretaceous successions are well developed in eastern Heilongjiang, northeastern China, including the Jixi Group in the west and the Longzhaogou Group in the east... The alternating marine and nonmarine coal-bearing Lower Cretaceous successions are well developed in eastern Heilongjiang, northeastern China, including the Jixi Group in the west and the Longzhaogou Group in the east. The correlation of these two lithostratigraphic groups with the nonmarine Jehol Group is important for dating the exceptionally well-preserved Jehol Biota. The Early Cretaceous marine fossils recovered from eastern Heilongjiang include ammonites, bivalves, radiolarians, foraminifers and dinocysts. During the early Aptian transgression the ammonite fauna entered the Hulin and Mishan areas and the bivalve Aucellina fauna in the Jixi area. This enables correlation of the marine lower part of the Chengzihe Formation of the Jixi Group with the Qihulin Formation of the Longzhaogou Group. 展开更多
关键词 Lower Cretaceous aptian ALBIAN Marine-Nonmarine Correlation MARINE FOSSILS EASTERN Heilongjiang NORTHEASTERN China
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Aptian biostratigraphy in South Zagros Basin, southwest Iran 被引量:2
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作者 Massih Afghah Arash Shaabanpour Haghighi 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第2期277-288,共12页
The Khami group within the petroliferous Zagros Basin of Iran includes the Surmeh, Hith, Fahliyan, Gadvan and Dariyan formations. The Dariyan Formation, previously known as Orbitolina limestone is very signif-icant as... The Khami group within the petroliferous Zagros Basin of Iran includes the Surmeh, Hith, Fahliyan, Gadvan and Dariyan formations. The Dariyan Formation, previously known as Orbitolina limestone is very signif-icant as a reservoir rock in the Zagros Basin. In this study, the age of the Dariyan Formation is examined based on biostratigraphic and paleontological investigations. 236 m of Dariyan Formation sediments in the sections at Kuh-e Rahmat (north) and Nour-Abad (west) of Iran were selected to study its biostratigraphy. According to the lithostratigraphic investigations, the Dariyan Formation in these sections is subdivided into three: lower, middle and upper, which include thin-bedded to medium-bedded and massive lime-stone. Micropaleontologic study of the Dariyan Formation has led to the recognition of two biozones in the Nour-Abad area and one biozone in the Kuh-e Rahmat stratigraphic column. Diagnostic foraminifera in these sections are as follows: Globigerinel oides algerianus Cushman and Ten Dam, Globigerinelloides fer-reolensis Moullade, Globigerinelloides maridalensis (Bolli), Globigerinelloides paragottisi Verga and Permoli Silva, Hedbergel a aptiana Bartenstein, Hedbergel a excelsa Longoria, Hedbergel a luterbacheri Longoria, Hedbergella occulta Longoria, Hedbergella ruka (Banner et al.), Hedbergella similis Longoria, Hedbergella trocoidea (Gandolfi), Muricohedbergella delrioensis (Carsey), Pseudoplanomalina cheniourensis Sigal, Con-icorbitolina conica d'Archiac, Iraqia sp., Mesorbitolina parva Douglass, Mesorbitolina pervia Douglass, Meso-rbitolina ovalis Gorog and Arnaud-Vanneau, Mesorbitolina subconcava Leymerie, Mesorbitolina texana (Roemer), Mesorbitolina ovalis-pervia Cherchi and Schroeder, Debarina hahounerensis Fourcade et al., Marssonel a trochus (d'Orbigny), Nezzazata sp., Orbitolina sp., Textularia sp. 展开更多
关键词 aptian Biostratigraphy Foraminifera Zagros Fars Iran
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Araucarian cone-scale complexes,newly found in Aptian Kitadani Formation of Tetori Group in Fukui Prefecture,Central Japan
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作者 Hirokazu Yukawa Atsushi Yabe 《Global Geology》 2019年第4期280-288,共9页
This study reports on two forms of Araucarian cone-scale complexes from the Aptian Kitadani Formation of the Tetori Group in Fukui Prefecture,Central Japan.One of these has been identified as a new fossil species:Arau... This study reports on two forms of Araucarian cone-scale complexes from the Aptian Kitadani Formation of the Tetori Group in Fukui Prefecture,Central Japan.One of these has been identified as a new fossil species:Araucarites kitadaniensis Yabe et Yukawa sp.nov.This is the first known occurrence of Araucarian macrofossils from the Tetori Group,indicating that this group was substantially diverse during that time period.This finding concurs with previous palynological investigations at the site,supporting the hypothesis that Araucarian plants began to diversify during Aptian global warming. 展开更多
关键词 Araucarian cone-scale complexes Araucarites kitadaniensis Yabe et Yukawa sp.nov. aptian Early Cretaceous Japan
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Geotechnical Study of the Aptian Limestone of the Kef Region,Northwestern Tunisia:Evaluation for Industrial Use
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作者 Imed Ben Salah Moufida Ben M’Barek Jemai +1 位作者 Safa Mezza Mabrouk Boughdiri 《Open Journal of Geology》 2018年第12期1084-1101,共18页
This study aims to the initial characterization of Aptian sedimentary limestones in the Kef region located in the North-West of Tunisia in order to use in industrial fields. The limestone samples were collected from t... This study aims to the initial characterization of Aptian sedimentary limestones in the Kef region located in the North-West of Tunisia in order to use in industrial fields. The limestone samples were collected from three outcrops respectively named Jebel Jerissa, Jebel Hmeima and Jebel Harraba. A geochemical characterization highlights a variation of the weight percentage (wt%) as follows: CaO (53 - 55), MgO (0.04 - 0.28), Al2O3 (0.07 - 0.51), Fe2O3 (0.41 - 2.87), and a loss on ignition (41.62 - 43.35). The other oxides (K2O, SO3, Na2O) are in trace amounts. Mineralogical analysis revealed that limestones contain more than 95% of calcite and the clay impurities are the minor phases detected. Petrographic study showed that these limestones are packestone-wakestone type. The hardness of Aptian limestones crosses the upper limit of the hard domain. Geotechnical tests reveal a Dry Micro Deval (MDS) coefficient varying from 23% to 33%, a Wet Micro Deval (MDH) coefficient with values oscillating around 26% to 36%, a Los Angeles coefficient (LA) about 25% against a value of the compressive strength ranging from 593 Kg/cm2 to 866 Kg/cm2. The gravimetric tests highlighted a flexural strength value from 106 Kg/cm2 at 208 Kg/cm2, while the ultrasonic coefficient oscillates from 4876 m/s to 5233 m/s, indicating the low porosity of these limestone (0.5% to 1%). The density recorded an average value of 2.50 g/cm3. The various properties studied have proved that the limestone studied can be used in various industrial fields such steel industry, aggregate, cement industry and marble. 展开更多
关键词 aptian Limestone Geotechnical Properties Geochemical Properties Industrial Use
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Middle-late Holocene environment change induced by climate and human based on multi-proxy records from the middle and lower reaches of Yangtze River,eastern China 被引量:2
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作者 Rui KE Xiayun XIAO +3 位作者 Changting CHI Aubrey HILLMAN Baoyan JIA &Xiangdong YANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2023年第7期1450-1467,共18页
Our knowledge about the interaction between human activities and the environment in the middle-late Holocene remains incomplete.Core C1 in Lake Chaohu from the middle and lower reaches of Yangtze River (MLYR),eastern ... Our knowledge about the interaction between human activities and the environment in the middle-late Holocene remains incomplete.Core C1 in Lake Chaohu from the middle and lower reaches of Yangtze River (MLYR),eastern China,provides an opportunity to investigate vegetation and climate changes,human activities,and East Asian summer monsoon(EASM) evolution since 5100 cal.yr BP.These variables are assessed based on radiocarbon dating,pollen and charcoal records,and magnetic susceptibility (χ_(lf)),median grain size and TP.Results reveal a hiatus in sedimentation between 2080 and 730 cal.yr BP in the western part of Lake Chaohu,which is common in most lakes in the MLYR.Evergreen and deciduous broadleaved mixed forest retreated gradually after 3650 cal.yr BP,and was replaced by secondary Pinus forest after at least 730 cal.yr BP.Intense agricultural activities and vegetation clearance are first detected at 2520 cal.yr BP.Human settlements expanded from the lake front wetlands (during the period 2520–2080 cal.yr BP) to remote high-altitude areas(2080–400 cal.yr BP),and then returned to the lake front to reclaim the wetlands and lake (after 400 cal.yr BP).A gradual trend of recessional EASM strength from 4300 cal.yr BP and centennial-scale variations of EASM during the period5100–3650 cal.yr BP are revealed.The reduction of summer insolation,southward shift of the ITCZ,and El Ni?o Southern Oscillation may control the intensity of EASM and climate on a large regional scale. 展开更多
关键词 POLLEN Environment change Human activity Lake sediment middle-late Holocene Middle and lower reaches of Yangtze River
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Geochronology,Eruption Sequence and Geochemistry of Mid-Late Jurassic Volcanics South of Manzhouli:Petrogenesis and Implications for Mesozoic Tectonic Regime Transformation
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作者 BAI Yuling WANG Tao +2 位作者 WANG Zongqi YAN Jie ZHANG Ai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第4期1112-1131,共20页
To the south of Manzhouli,Hulunbuir,Inner Mongolia,experienced a tectonic regime transformation from compression to extension in the mid-Mesozoic.Based on systematic research of the volcanics,petrology,volcanic facies... To the south of Manzhouli,Hulunbuir,Inner Mongolia,experienced a tectonic regime transformation from compression to extension in the mid-Mesozoic.Based on systematic research of the volcanics,petrology,volcanic facies,chronology and geochemistry of rocks in the Buridun area,two stages of volcanics are identified.The first stage named the trachyte series was formed in the late Middle Jurassic(167-163 Ma),its eruption rhythm is pyroxene trachyandesite-trachyandesite-trachyte,and its origin rock is basic volcanics from thickened lower crust,with a tectonic setting in the collision orogeny after the closure of the Mongolia Okhotsk Ocean(MOO).The second stage is a bimodal volcanic rock,formed in the early Late Jurassic(163-160 Ma).The eruption rhythm of basic volcanics in this stage is basaltic andesite-basalt-olivine basalt,which comes from the metasomatized lithospheric mantle,the acidic volcanics of which being characterized by the eruption rhythm of sedimentary-explosive-overflow facies,which came from the partial melting of newly formed lower crust,and this shows the characteristics of A-type granite;the tectonic setting is extension of the lithosphere after collision and closure of the MOO.The changes in the formation age and tectonic setting of the two stages of volcanics demonstrate that the transition time from the compressive system to the extensional system south of Manzhouli is about 163 Ma. 展开更多
关键词 tectonics GEOCHRONOLOGY middle-late Jurassic volcanics eruption sequence Inner Mongolia
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First Record of Sexual Dimorphism in Toxasterid Echinoid Heteraster from the Early Cretaceous Deposits of the Kopet-Dagh Basin,NE Iran
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作者 Hossein KAMYABI SHADAN Morteza TAHERPOUR KHALIL-ABAD 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第5期1318-1334,共17页
Spatangoid echinoids belonging to Heteraster found in the Lower Cretaceous limestones and calcareous deposits of the Tirgan and Sarcheshmeh formations(Barremian-Aptian)in the Bahman jan-Bala stratigraphic section on t... Spatangoid echinoids belonging to Heteraster found in the Lower Cretaceous limestones and calcareous deposits of the Tirgan and Sarcheshmeh formations(Barremian-Aptian)in the Bahman jan-Bala stratigraphic section on the northern flank of the Borouj syncline,situated in the eastern Kopet-Dagh Basin,northeastern Iran are assessed as a sexually dimorphic species.Sexual dimorphism is a common feature in echinoids and,in this study of Heteraster renngarteni Poretzkaja,1961,sexual dimorphism has been detected for the first time in the family Toxasteridae. 展开更多
关键词 invertebrate paleontology ECHINODERMATA Heteraster sexual dimorphism Barremian–aptian Kopet-Dagh Iran
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下刚果盆地油气成藏主控因素及勘探方向 被引量:27
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作者 丁汝鑫 陈文学 +2 位作者 熊利平 林卫东 刘志强 《特种油气藏》 CAS CSCD 2009年第5期32-35,共4页
下刚果盆地油气成藏条件非常有利,尤其盆地内沉积了阿普第阶盐岩层,发育多种类型盐相关构造,形成多种类型圈闭,同时盐岩层又是非常好的盖层。但该套盐岩层的存在也使下刚果盆地盐下、盐上油气成藏条件产生较大差异:盐下地层油气成藏的... 下刚果盆地油气成藏条件非常有利,尤其盆地内沉积了阿普第阶盐岩层,发育多种类型盐相关构造,形成多种类型圈闭,同时盐岩层又是非常好的盖层。但该套盐岩层的存在也使下刚果盆地盐下、盐上油气成藏条件产生较大差异:盐下地层油气成藏的主控因素为伸展构造有关的圈闭,未来重点勘探仍以寻找伸展构造有关的油气藏类型为主要方向;盐上白垩系油气成藏的主控因素为圈闭和储层,未来勘探应以寻找与阿尔布阶Pinda组碳酸盐岩和Vermelha组的滨岸砂岩为储层并与盐构造相关的油气藏为重点;第三系油气成藏的主控因素则为烃源岩成熟度、圈闭及浊积砂体的发育,未来重点勘探方向为寻找深水—超深水区盐构造与浊积砂体复合型油气藏。 展开更多
关键词 阿普第阶盐岩 成藏主控因素 勘探方向 下刚果盆地
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新疆塔里木盆地早白垩世克孜勒苏群孢粉组合 被引量:12
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作者 江德昕 王永栋 +3 位作者 何卓生 董凯林 倪庆 田宁 《微体古生物学报》 CSCD 北大核心 2006年第4期371-391,共21页
基于新疆塔里木盆地西南区和东南区下白垩统克孜勒苏群发现的孢子花粉57属96种的研究,建立了克孜勒苏群下亚旋回和上亚旋回孢粉组合,并根据孢粉组合讨论了地层时代。克孜勒苏群孢粉组合以松杉目的优势、真蕨目海金沙科的显赫和原始被子... 基于新疆塔里木盆地西南区和东南区下白垩统克孜勒苏群发现的孢子花粉57属96种的研究,建立了克孜勒苏群下亚旋回和上亚旋回孢粉组合,并根据孢粉组合讨论了地层时代。克孜勒苏群孢粉组合以松杉目的优势、真蕨目海金沙科的显赫和原始被子植物的出现为特征。克孜勒苏群下亚旋回孢粉组合与欧洲韦尔登期(陆相尼欧克姆期)和北美巴列姆期孢粉组合可以对比,克孜勒苏群上亚旋回孢粉组合与欧亚大陆、北美和澳大利亚阿普第期至阿尔必期孢粉组合可以对比。根据孢粉学证据,克孜勒苏群下亚旋回应属于尼欧克姆期,或赫特里夫期至巴列姆期,克孜勒苏群上亚旋回应归于阿普第期至阿尔必期。 展开更多
关键词 孢粉组合 尼欧克姆期 阿普第期-阿尔必期 早白垩世 克孜勒苏群 塔里木盆地
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甘肃平凉安国镇白垩系六盘山群的孢粉植物群 被引量:16
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作者 李建国 杜宝安 《古生物学报》 CAS CSCD 北大核心 2006年第4期498-513,共16页
对甘肃—宁夏交界处六盘山群一个露头剖面进行了孢粉分析,从和尚铺组、李洼峡组、马东山组和乃家河组中获得了孢粉化石。这些材料表明,六盘山群的孢粉植物群中白垩纪分子丰度高、分异度大,时代可能为晚Aptian—早、中Albian。孢粉反映... 对甘肃—宁夏交界处六盘山群一个露头剖面进行了孢粉分析,从和尚铺组、李洼峡组、马东山组和乃家河组中获得了孢粉化石。这些材料表明,六盘山群的孢粉植物群中白垩纪分子丰度高、分异度大,时代可能为晚Aptian—早、中Albian。孢粉反映当时的气候条件中性偏干,其中和尚铺组和乃家河组比李洼峡组和马东山组要更干一些。根据孢粉资料,六盘山群的和尚铺组至乃家河组的沉积可与盆地主体的志丹群的上部即泾川组对比,三桥组则可能相当于罗汉洞组。陕甘宁盆地西部边缘区缺少相当于志丹群宜君组至环河华池组的早白垩世早期的沉积。 展开更多
关键词 孢粉 六盘山群 aptian一早、中Albian
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松辽盆地早白垩世淡水沟鞭藻类 被引量:13
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作者 乔秀云 何承全 高瑞祺 《古生物学报》 CAS CSCD 北大核心 1992年第1期30-38,137-139,共9页
本文描述了松辽盆地早白垩世沙河子组一登娄库组(别里亚士期—阿普第早期)淡水角藻类沟鞭藻囊孢4属、5新种和2个未定种,并对拟蝙蝠藻属(Vesperopsis Bint, 1986)进行了修订。
关键词 松辽盆地 早白垩世 淡水 沟鞭藻类
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