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Eruptive xanthomas in a patient with severe hypertriglyceridemia:A case report
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作者 Ci Ren Ling Zhu +3 位作者 Yan-Chao Niu Lian-Yu Tu Zhou-Feng Jin Jian Zhang 《World Journal of Clinical Cases》 SCIE 2024年第16期2842-2846,共5页
BACKGROUND Xanthomatosis,a metabolic disorder causing yellow growths(xanthomas),poses challenges in lipid metabolism.This case study introduces the first documented instance within China's Yi population,emphasizin... BACKGROUND Xanthomatosis,a metabolic disorder causing yellow growths(xanthomas),poses challenges in lipid metabolism.This case study introduces the first documented instance within China's Yi population,emphasizing the need to explore dietary habits and treatment strategies tailored to this specific community.CASE SUMMARY Xanthomatosis is a metabolic disorder where lipid metabolism goes awry,resulting in the development of yellowish growths called xanthomas.A male patient,47 years of age,from China's Yi population,who is obese,visited our dermatology clinic complaining of widespread,non-painful rashes that have been present for two weeks.The patient works as a chef and has a diet that frequently includes oily and greasy foods.This case represents the initial documentation of xanthomatosis within the Yi population in China,offering a theoretical foundation for understanding dietary patterns and treatment options specific to the Yi community.CONCLUSION The first report of xanthomatosis in the Yi population in China lays a theoretical foundation for understanding Yi dietary patterns and treatment. 展开更多
关键词 eruptive xanthomas HYPERTRIGLYCERIDEMIA Yi ethnicity DERMATOLOGY Chef Case report
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Subaqueous volcanic eruptive facies,facies model and its reservoir significance in a continental lacustrine basin:A case from the Cretaceous in Chaganhua area of southern Songliao Basin,NE China 被引量:1
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作者 SHAN Xuanlong MU Hansheng +5 位作者 LIU Yuhu LI Ruilei ZHU Jianfeng SHI Yunqian LENG Qinglei YI Jian 《Petroleum Exploration and Development》 SCIE 2023年第4期826-839,共14页
The conventional lithofacies and facies model of subaerial and marine pyroclastic rocks cannot reflect the characteristics of subaqueous volcanic edifice in lacustrine basins.In order to solve this problem,the lithofa... The conventional lithofacies and facies model of subaerial and marine pyroclastic rocks cannot reflect the characteristics of subaqueous volcanic edifice in lacustrine basins.In order to solve this problem,the lithofacies of subaqueous eruptive pyroclastic rocks is discussed and the facies model is established by taking the tuff cone of Cretaceous Huoshiling Formation in the Chaganhua area of the Changling fault depression,Songliao Basin as the research object.The results indicate that the subaqueous eruptive pyroclastic rocks in the Songliao Basin can be divided into two facies and four subfacies.The two facies are the subaqueous explosive facies and the volcanic sedimentary facies that is formed during the eruption interval.The subaqueous explosive facies can be further divided into three subfacies:gas-supported hot pyroclastic flow subfacies,water-laid density current subfacies and subaqueous fallout subfacies.The volcanic sedimentary facies consists of pyroclastic sedimentary rocks containing terrigenous clast subfacies.A typical facies model of the tuff cone that is formed by subaqueous eruptions in the Songliao Basin was established.The tuff cone is generally composed of multiple subaqueous eruption depositional units and can be divided into two facies associations:near-source facies association and far-source facies association.The complete vertical succession of one depositional unit of the near-source facies association is composed of pyroclastic sedimentary rocks containing terrigenous clast subfacies,gas-supported hot pyroclastic flow subfacies,water-laid density current subfacies and subaqueous fallout subfacies from bottom to top.The depositional unit of the far-source facies association is dominated by the subaqueous fallout subfacies and contains several thin interlayered deposits of the water-laid density current subfacies.The gas-supported hot pyroclastic flow subfacies and the pyroclastic sedimentary rocks containing terrigenous clast subfacies are favorable subaqueous eruptive facies for reservoirs in continental lacustrine basins. 展开更多
关键词 continental lacustrine basin Songliao Basin Chaganhua area Cretaceous Huoshiling Formation subaqueous eruption volcanic facies tuff cone
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Eruptive Cutaneous Collagenoma: Report of Two Cases 被引量:1
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作者 Jian Wu Mei-Hong Cai +4 位作者 Ling-Ling Chen Lei Wu Xiao-Jian Chen Hong-Yan Zhu Feng Shi 《International Journal of Dermatology and Venereology》 2021年第2期128-130,共3页
Introduction:Eruptive cutaneous collagenoma is non familial connective tissue nevi of unknown etiology presented with an abrupt onset.To date,the literatures on eruptive cutaneous collagenoma are extremely rare in chi... Introduction:Eruptive cutaneous collagenoma is non familial connective tissue nevi of unknown etiology presented with an abrupt onset.To date,the literatures on eruptive cutaneous collagenoma are extremely rare in china.Case present:Two women presented with multiple asymptomatic,skin-colored papules and nodules on the trunk and extremities with no systemic involvement.Histopathology revealed dense,coarse collagen fibers by hematoxylin-esoin stain and decreased,fragmented elastic fibers by Elastic stain compared with the normal skin.Basing on these findings,the diagnosis of eruptive cutaneous collagenoma was made.No specific treatment was given.Discussion:Eruptive cutaneous collagenoma is a very rare dermatosis that is often misdiagnosed as other connective tissue nevi.The pathogenesis is unclear,and also no efficient treatment is available.It is usually diagnosed based on clinical and histopathological findings.Conclusion:The present cases are relatively rare type of eruptive cutaneous collagenoma that provide more experience for clinician,and may be helpful for them to make correct diagnosis for suspicious cases. 展开更多
关键词 case report eruptive cutaneous collagenoma chinese women trunk and extremities
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Derivation of the Spiral Motion of an Eruptive Prominence and Its Explanation
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作者 Xiao-Ma Gu Shu-Hua Zhong +1 位作者 Hong-Fei Liang La-Sheng Zhan 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第5期617-624,共8页
A 2D velocity field of the eruptive prominence (EP) of 1991 March 5 is obtained from its spectral data observed at the Yunnan Observatory and the velocity distributions along the entrance slit are derived for differ... A 2D velocity field of the eruptive prominence (EP) of 1991 March 5 is obtained from its spectral data observed at the Yunnan Observatory and the velocity distributions along the entrance slit are derived for different observing frames. Under the assumption that matter in the EP undergoes axial, radial and possible rotational motions, we construct a theoretical velocity distribution of the EP along the entrance slit, to derive, by fitting, the angular velocity of rotation ω and the other three parameters (axial velocity v0, radial velocity vr and the angle between the EP plane and the line of sight Ф). We found: an averaged angular velocity ω of 3.0 × 10^-3 arc s^-1 and the variation of ω with the height above the solar limb. As the EP rises, the matter within it in fact moves along a spiral path around its axis. The spiral motion may be explained by the theory of plasma ‘double pole diffusion' (DPD) caused by a sharp density gradient between the eruptive prominence and the surrounding corona. A theoretical angular velocity ω′ is estimated based on the DPD and basically coincides with ω obtained from the optimal velocity fitting. 展开更多
关键词 SUN eruptive prominence -- Sun Spiral motion
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Diagnostic imaging:Morphological and eruptive disturbances in the permanent teeth
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作者 Deepak Sharma Ramneet Kaur +2 位作者 Suneet Monga Simerjeet Kaur Ruchika Kundra 《World Journal of Stomatology》 2015年第2期72-80,共9页
This paper reviewed the literature on newer threedimensional imaging techniques and their applications in diagnosis and treatment planning of various dental anomalies. Developmental anomalies can occur during any of t... This paper reviewed the literature on newer threedimensional imaging techniques and their applications in diagnosis and treatment planning of various dental anomalies. Developmental anomalies can occur during any of the developmental stages and are manifested clinically after the tooth is fully formed. These dental anomalies may involve a single tooth, a group of teeth, or the entire dentition. Two-dimensional diagnosticimaging, including periapical, occlusal, panoramic, or cephalometric radiographs are essential in localization and management of morphological and eruptive disorders. However, due to their inherent limitations such as insufficient precision because of unusual projection errors and lack of information about spatial relationships, these methods are considered unreliable. Thus, the use of newer image acquisition techniques that allow comprehensive three dimensional imaging and visualization of dental abnormalities is highly recommended for making a confirmatory diagnosis. The significance of accurate endodontic, surgical and orthodontic treatment planning in dental abnormalities cannot be overstated as it pertains to critical anatomic landmarks such as proximity to adjacent teeth or the mandibular canal. The precise information on spatial relationships provided by multiplanar imaging helps the dental surgeon to establish more accurate diagnosis, management strategies and also increases the patient safety. This review highlights the use of high-end diagnostic imaging modalities in diagnosis of the various morphologic and eruptive dental abnormalities. 展开更多
关键词 Three-dimensional IMAGING Spiral COMPUTED TOMOGRAPHY Magnetic resonance IMAGING eruptive MALFORMATIONS MORPHOLOGICAL disturbances Conebeam COMPUTED TOMOGRAPHY
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Eruptive Variables
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作者 Angel Fierros Palacios 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第2期155-160,共6页
In this paper, a solution of the problem about how a massive star knows that it gets rid of its excess of mass before it can become a white dwarf, a pulsar or a black hole, is proposed. Many astronomers believe that t... In this paper, a solution of the problem about how a massive star knows that it gets rid of its excess of mass before it can become a white dwarf, a pulsar or a black hole, is proposed. Many astronomers believe that this may take place in the form of a nova and supernova outburst, as well as in the form of a continuous outflow of gas [1]. 展开更多
关键词 eruptive Variables
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Molar incisor hypomineralization and pre-eruptive intracoronal lesions in dentistry-diagnosis and treatment planning
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作者 Uri Zilberman Jomanna Hassan Shirley Leiboviz-Haviv 《World Journal of Stomatology》 2019年第2期20-27,共8页
The aim of this study is to report the diagnostic features, prevalence, mineral content, clinical significance and treatment options of molar incisor hypomineralization(MIH) and pre-eruptive intracoronal lesions(PEIR)... The aim of this study is to report the diagnostic features, prevalence, mineral content, clinical significance and treatment options of molar incisor hypomineralization(MIH) and pre-eruptive intracoronal lesions(PEIR), in order to minimize miss-treatment of primary and permanent teeth in young children.MIH was defined as the occurrence of hypomineralization of one up to four permanent first molars from a systemic origin and frequently associated with affected incisors. PEIR are lesions that are located in the occlusal portion of the crown of unerupted permanent or primary teeth. The prevalence of MIH was reported between 2.5%-40% in the permanent first molars and 0%-21.8% in primary second molars. PEIR was observed in 2%-8% of children, mainly in mandibular second premolars and second and third permanent molars. A number of possible causes for MIH were mentioned, including environmental changes, diet and genetics in prenatal and postnatal periods, but all are questionable. In PEIR, the resorption of the intracoronal dentine begins only after crown development is complete and is caused by giant cells resembling osteoclast observed histologically on the dentine surface close to the pulp. The mineral content in MIH is reduced in comparison to normal enamel and dependent on the severity of the lesion. In PEIR the resorbed surface of enamel showed less mineral content. The hypomineralized enamel in MIH is not suitable for restorations with amalgam or composite materials, and the best material should be based on remineralization material like glass-ionomers. Similar, the resorbed dentin surface in PEIR should be covered by the biocompatible and remineralizing glass-ionomer cement. 展开更多
关键词 MOLAR INCISOR hypomineralization Pre-eruptive intracoronal LESIONS Glassionomer cements Enamel DENTIN
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A comparison study of a solar active-region eruptive filament and a neighboring non-eruptive filament 被引量:2
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作者 Chao-Wei Jiang Shi-Tsan Wu +1 位作者 Xue-Shang Feng Qiang Hu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第1期151-158,共8页
Solar active region (AR) 11283 is a very magnetically complex region and it has produced many eruptions. However, there exists a non-eruptive filament in the plage region just next to an eruptive one in the AR, whic... Solar active region (AR) 11283 is a very magnetically complex region and it has produced many eruptions. However, there exists a non-eruptive filament in the plage region just next to an eruptive one in the AR, which gives us an opportunity to perform a comparison analysis of these two filaments. The coronal magnetic field extrapolated using our CESE-MHD-NLFFF code reveals that two magnetic flux ropes (MFRs) exist in the same extrapolation box supporting these two filaments, respectively. Analysis of the magnetic field shows that the eruptive MFR contains a bald-patch separatrix surface (BPSS) co- spatial very well with a pre-eruptive EUV sigmoid, which is consistent with the BPSS model for coronal sigmoids. The magnetic dips of the non-eruptive MFRs match Hα observation of the non-eruptive filament strikingly well, which strongly supports the MFR-dip model for filaments. Compared with the non-eruptive MFR/filament (with a length of about 200 Mm), the eruptive MFR/filament is much smaller (with a length of about 20 Mm), but it contains most of the magnetic free energy in the extrapolation box and holds a much higher free energy density than the non-eruptive one. Both the MFRs are weakly twisted and cannot trigger kink instability. The AR eruptive MFR is unstable because its axis reaches above a critical height for torus instability, at which the overlying closed arcades can no longer confine the MFR stably. On the contrary, the quiescent MFR is very firmly held by its overlying field, as its axis apex is far below the torus-instability threshold height. Overall, this comparison investigation supports that an MFR can exist prior to eruption and the ideal MHD instability can trigger an MFR eruption. 展开更多
关键词 magnetic fields -- Sun: corona -- Sun: filaments -- Sun: eruptions
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Modelling of Eruptive Fire Occurrence and Behaviour 被引量:1
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作者 Jacques-Henri Balbi Frangois Joseph Chatelon +3 位作者 Jean Louis Rossi Albert Simeoni Domingos Xavier Viegas Carlos Rossa 《Journal of Environmental Science and Engineering(B)》 2014年第3期115-132,共18页
关键词 森林火灾 行为建模 喷发 实验室规模 物理模型 非线性关系 人员伤亡 消防人员
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Variations in the Patterns of Precipitation in the Watershed of the Ambato River Associated with the Eruptive Process of the Tungurahua Volcano in Ecuador
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作者 Iván Ríos García Abel Solera 《Open Journal of Modern Hydrology》 2015年第4期121-139,共19页
The Tungurahua, located in the Cordillera de los Andes, is the volcano with the most eruptive activity in Ecuador nowadays. 1993 records the eruptive initial process and in August of 1999, after almost 80 years of res... The Tungurahua, located in the Cordillera de los Andes, is the volcano with the most eruptive activity in Ecuador nowadays. 1993 records the eruptive initial process and in August of 1999, after almost 80 years of rest, the volcano begins an explosive eruptive period. This research examines the effects of the eruptive process of the volcano in the patterns of change in precipitation in the short term in a hydrographic watershed. Their results are intended to contribute to the studies carried out to understand the weather and the factors influencing its variability at local and global level. It aims also to contribute with technical data in the debate about experimenting with artificial volcanoes to weather modification. The analysis demonstrates a process of redistribution of rainfall, with significant increases in rainfall from 42.25% on December, and significant decreases of 40.03% on September, during the presence of the eruptive process. 展开更多
关键词 VOLCANIC ERUPTION RAINFALL Variability Tungurahua
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Hydrothermal Alteration of Basaltic Rocks at Eruptive Vents on Mount Cameroon Volcano, West Africa
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作者 Akumbom Vishiti Taboko Armstrong +2 位作者 Elisha Mutum Shemang Jacques Etame Cheo Emmanuel Suh 《International Journal of Geosciences》 2018年第9期513-527,共15页
The study of changes in rocks due to interaction with hydrothermal fluids at active volcanoes provides insights into wall rock alteration associated with ore deposits formed in the geological past. Therefore, the natu... The study of changes in rocks due to interaction with hydrothermal fluids at active volcanoes provides insights into wall rock alteration associated with ore deposits formed in the geological past. Therefore, the nature of mineral alteration and chemical changes experienced by wall rocks can be investigated at eruptive sites on active volcanoes and the results used to better constrain ore-forming processes. In this study, we investigated the alteration at eruptive sites at Mount Cameroon volcano. These eruptive vents lie along NE-SW-trending fissures that define the Mount Cameroon rift. The vents are surrounded by cones composed largely of pyroclastic materials and to a lesser extent lava. Fumaroles (volcanic gases) rising through the vents during and after the 1999 eruption have resulted in the alteration of the pyroclastic robble along the fissures and the inner walls of the cones. Consequently, altered basaltic materials are covered with thin films of reddish, yellowish to whitish secondary minerals. These coatings result from an interaction between the surfaces of the basaltic glass with volcanically-derived acidic fluids. Petrographic investigations and XRD analysis of the basalts have identified primary mineral phases, such as olivine, pyroxene (mainly augite) and feldspars. Alteration products revealed include ubiquitous silica as well as gypsum, magnetite, feldspar, alunite and jarosite. Jarosite occurrence indicates that SO2 is the primary volcanically-derived acid source involved in coating formation. High contents of sulfur identified in the basalts indicate that melts at Mount Cameroon can be sulfur saturated as backed by previous melt inclusion data. Whole rock geochemical analysis shows a gain in silica in the altered samples and this ties with the mass balance calculations although minor gains of Al2O3, , MgO, MnO, CaO and K2O are shown by some samples. 展开更多
关键词 Mount Cameroon 1999 ERUPTION Fumarole Wall Rock ALTERATION Mass Bal-ance
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抗癫痫药物致住院患者药疹的临床表现及防治策略
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作者 陈慧 张青霞 +4 位作者 张艺丹 林于樱 赵琛 赵宇 朱威 《中国药业》 CAS 2024年第1期124-128,共5页
目的 初步评价抗癫痫药物的安全性,并探讨抗癫痫药物引发药疹的防治策略。方法 回顾性分析医院神经内科或儿科2016年1月至2022年12月收治的经皮肤科会诊确诊为由抗癫痫药物致药疹的15例住院患者的临床资料,总结常见引发药疹的抗癫痫药... 目的 初步评价抗癫痫药物的安全性,并探讨抗癫痫药物引发药疹的防治策略。方法 回顾性分析医院神经内科或儿科2016年1月至2022年12月收治的经皮肤科会诊确诊为由抗癫痫药物致药疹的15例住院患者的临床资料,总结常见引发药疹的抗癫痫药物种类、药疹的分型、系统受累情况、药疹治疗方法的选择和预后。结果 15例患者中,最常引发药疹的药物为奥卡西平(6/15);药疹分型中以麻疹型最常见(13/15),2例Stevens-Johnson综合征(SJS)型分别由奥卡西平和苯巴比妥引起;除药疹外,患者常合并肝功能异常(8/15)、发热(7/15)和外周血嗜酸性粒细胞水平升高(6/15)。经停用/更换致敏抗癫痫药物、抗过敏等对症治疗后,药疹完全消退、系统损害恢复正常。结论 多种抗癫痫药物均可引发药疹,抗癫痫药物引发的药疹以麻疹型多见,但应警惕SJS型的出现及肝功能损害。及时停用致敏药物并更换抗癫痫药物的种类,使用糖皮质激素和(或)抗组胺药物对症治疗,对抗癫痫药物引发的药疹疗效较好。 展开更多
关键词 抗癫痫药物 药疹 临床表现 防治策略
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从长英质侵入体揭示火山喷发过程与岩浆通道系统
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作者 马昌前 刘彬 +6 位作者 薛振华 邹博文 黄贵治 连泉程 高珂 孙洋 王连训 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第7期1997-2018,共22页
汇聚板块边缘的大型长英质火山喷发是地球上最具破坏性的自然灾害之一。然而,与这些火山相关的岩浆通道系统的结构及其对火山活动的控制方式迄今仍知之甚少。基于在青藏高原北部东昆仑造山带三叠纪火山岩与侵入体关系的观察以及全球岩... 汇聚板块边缘的大型长英质火山喷发是地球上最具破坏性的自然灾害之一。然而,与这些火山相关的岩浆通道系统的结构及其对火山活动的控制方式迄今仍知之甚少。基于在青藏高原北部东昆仑造山带三叠纪火山岩与侵入体关系的观察以及全球岩浆通道系统的研究进展,本文提出要将火山机构与侵入体结合起来开展研究,通过重建岩浆通道系统来揭示侵入体(古岩浆储库)与火山活动的潜在联系。本文指出,地球上只有少部分侵入岩与火山活动存在密切关系,这些侵入岩可能是抽取火山喷发物质后留下的岩浆储库残余物质。有些岩浆储库不仅为火山喷发提供物质,还在提供火山喷发动力、控制火山喷发方式在溢流式与爆炸式之间的转换以及影响火山机构定位等方面发挥着关键作用。富挥发分的流体大量溢出地表会减少大型伟晶岩型和斑岩型矿床的形成机会,特别是在爆炸式的长英质火山喷发过程中。本文将岩浆通道系统划分为5个区域,即部分熔融区、岩浆聚集区、岩浆迁移区、岩浆侵位区和火山喷口区,这些区域构成了一个复杂的纵向递进、横向连接的岩浆网络系统,是构造环境(构造阶段)、地壳状态和岩浆动力学属性的耦合产物。为了深入理解长英质岩浆通道系统结构和动力学演化及其对火山活动机制的控制,本文建议要将火山机构、侵入体和围岩系统作为岩浆通道系统的组成部分,开展构造地质学、岩石学、矿物学、岩浆动力学、地球化学、地球物理学等多学科的综合研究,以精细解剖典型岩浆通道系统的组成和结构,重建其岩浆动力学过程。 展开更多
关键词 东昆仑 长英质岩浆 岩浆通道系统 火山喷发方式 侵入体 岩浆动力学
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改良型左甲状腺素钠相关药疹2例
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作者 高妍 陶蕾 +1 位作者 张群群 钱芳 《中国医药导刊》 2024年第4期417-420,共4页
优甲乐是一种人工合成外源性左甲状腺素,成分类似于甲状腺自然分泌的四碘甲状腺原氨酸,且可在外周器官中转化为游离三碘甲状腺原氨酸,并进一步结合受体,调节甲状腺功能。我院2例患者均为年轻女性,既往无药物及食物过敏史,也无家族遗传... 优甲乐是一种人工合成外源性左甲状腺素,成分类似于甲状腺自然分泌的四碘甲状腺原氨酸,且可在外周器官中转化为游离三碘甲状腺原氨酸,并进一步结合受体,调节甲状腺功能。我院2例患者均为年轻女性,既往无药物及食物过敏史,也无家族遗传史。入院后行甲状腺切除术,术后常规给予优甲乐预防甲状腺肿复发,且服用同一批次、同一厂家优甲乐。2例患者前后出现不同程度的药物性皮疹,经抗过敏治疗后好转。2例患者的不良反应均与优甲乐的服用具有时间相关性,考虑为优甲乐的新辅料甘露醇引起。甘露醇静滴时,常见的不良反应包括过敏性皮疹和荨麻疹。本研究基于我院2例优甲乐疑似引起药物性皮疹病例,综合分析患者相关指标变化,并结合国内外相近案例回顾分析,探讨药物性皮疹特点及可能机制,以期提高临床医师对这一现象的关注,并为该疾病的深入研究、促进优甲乐安全合理用药提供一定参考。 展开更多
关键词 改良型新药 左甲状腺素钠片 药疹 药品不良反应 病理机制
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陆相湖盆水下喷发火山岩储层特征及发育模式——以松辽盆地长岭断陷查干花次凹为例
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作者 任宪军 石云倩 靖伟 《油气藏评价与开发》 CSCD 北大核心 2024年第2期176-189,共14页
在松辽盆地长岭断陷陆相湖盆水下喷发的火石岭组火山碎屑岩中发现了工业油气,有广阔的勘探前景。研究针对火石岭组水下喷发火山碎屑岩储层的储集空间特征、物性特征及孔隙结构差异开展,分析不同类型储层物性差异原因及其形成和演化过程... 在松辽盆地长岭断陷陆相湖盆水下喷发的火石岭组火山碎屑岩中发现了工业油气,有广阔的勘探前景。研究针对火石岭组水下喷发火山碎屑岩储层的储集空间特征、物性特征及孔隙结构差异开展,分析不同类型储层物性差异原因及其形成和演化过程。主要有以下4个方面:①凝灰岩中火山玻璃含量较高,储集空间以脱玻化孔和溶蚀孔为主,并且粒度越粗物性越好,孔隙规模、孔径大小、孔隙丰度等方面逐渐变大;沉凝灰岩黏土矿物含量高,以黏土矿物晶间孔为主,物性差;凝灰质砂岩中长石、岩屑和浊沸石等易溶组分含量高,以溶蚀孔为主。②研究区火山碎屑岩储层原生孔隙不发育,储层较为致密,平均孔隙度为2.43%,渗透率平均值为0.076×10^(-3)μm^(2),粗粒凝灰岩孔隙度最高,其次是凝灰质砂岩和细粒凝灰岩,沉凝灰岩物性最差。③脱玻化作用是凝灰岩储层中高孔隙度和超低渗透率的重要原因,中成岩阶段的2次油气充注导致岩石发生有机酸溶蚀,此外,裂缝可以为有机酸和深部热液提供运移通道,导致后期溶蚀,并连接各种分散的溶蚀孔隙,提高储集空间的有效性。④近源相带气携水下火山碎屑流亚相粗粒凝灰岩储层是油气勘探的有利目标。 展开更多
关键词 松辽盆地 长岭断陷 陆相湖盆 水下喷发 火山碎屑岩储层 储层发育模式
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滇东地区裂谷盆地内火山-侵入岩序列与金属成矿
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作者 方维萱 郭玉乾 李天成 《地质学报》 EI CAS CSCD 北大核心 2024年第6期1776-1802,共27页
碱性岩浆对金属成矿和金属矿集区有独特控制作用,因火山—侵入岩序列与金属成矿和岩浆叠加侵入构造系统识别难度大,长期制约了深部勘探和找矿预测。本文以云南东川铁铜金矿集区(元古宙陆缘裂谷盆地)和个旧锡铜钨铯铷多金属矿集区(三叠... 碱性岩浆对金属成矿和金属矿集区有独特控制作用,因火山—侵入岩序列与金属成矿和岩浆叠加侵入构造系统识别难度大,长期制约了深部勘探和找矿预测。本文以云南东川铁铜金矿集区(元古宙陆缘裂谷盆地)和个旧锡铜钨铯铷多金属矿集区(三叠纪弧后裂谷盆地)为主,采用大比例尺构造岩相学填图新方法,解析研究了碱性岩浆活动有关的火山—侵入岩侵入序列与岩石组合、裂谷盆地演化和岩浆叠加侵入构造系统,揭示了它们与滇东地区铁氧化物铜金型(IOCG)、铜钴-金红石-稀土和锡铜钨铯铷多金属矿叠加成矿内在关系。研究认为:①云南东川铁铜金矿集区内,新太古代末期碱性岩类以方解石钠长岩(2520±14 Ma)和碱性铁质苦橄岩(2529±77 Ma)为主。新太古界—古元古界小溜口岩组(>2.50Ga)顶部古岩溶风化壳,受中元古代火山喷发—岩浆侵入构造叠加再造形成了特殊单元(独立填图单元,2.50~1.80Ga),它们是铜钴-金红石-稀土矿床的新找矿层位。②在中元古界因民组一段内,铁钠质碱性基性岩、铁钾质粗面岩和铁质碱性辉绿辉长岩等岩石组合形成于因民期火山断陷成盆期。因民组二段和三段是稀矿山式铁铜矿床储矿层位,铁铜矿层下盘铁钾质粗面岩为独居石型稀土成矿层位。在格林威尔造山期碱性钛铁质辉长岩(1097~1047 Ma)-碱性钛铁质闪长岩-碱性二长斑岩等碱性钛铁质侵入岩体,形成了白锡腊深部IOCG矿床和金红石富集成矿。③在个旧三叠纪弧后裂谷盆地内,三叠纪碱性苦橄岩和碱玄岩中形成了Sn-Cu-Zn-Li-Rb-Cs初始富集;在晚白垩世浅色花岗岩叠加成矿作用下,形成了金云母矽卡岩型锡铜钨铯铷矿床。④裂谷盆地内早期碱性岩中初始富集金属与后期富含成矿金属的碱性侵入岩叠加成矿可能是金属超常富集机理。在东川地区岩浆叠加侵入构造内,岩浆热液角砾岩筒对铜钴-金红石-稀土元素叠加富集成矿控制显著;在个旧地区,浅色花岗岩侵入于碱性苦橄岩-碱玄岩中,对金云母矽卡岩型锡铜钨钴铯铷矿床的叠加富集成矿控制显著。 展开更多
关键词 陆缘裂谷盆地 弧后裂谷盆地 火山—侵入岩序列 岩浆叠加侵入构造 碱性岩 关键矿产 滇东
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内蒙古锡林浩特地区晚新生代火山喷发序列研究
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作者 史志伟 白志达 +3 位作者 赵志丹 董国臣 王建伟 金笃斌 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第7期2087-2102,共16页
火山喷发序列是恢复火山活动历史的重要基础。锡林浩特火山群是大兴安岭-大同新生代火山喷发带中火山数量最多、喷发时间最长的火山群。本文从火山地质学入手,查明了火山堆积物之间及与沉积地层(离石黄土、马兰黄土和黑土)的叠置关系,... 火山喷发序列是恢复火山活动历史的重要基础。锡林浩特火山群是大兴安岭-大同新生代火山喷发带中火山数量最多、喷发时间最长的火山群。本文从火山地质学入手,查明了火山堆积物之间及与沉积地层(离石黄土、马兰黄土和黑土)的叠置关系,并根据火山结构组成、形貌特征、喷发类型、火山岩类型及火山锥体的风化降解程度等,结合光释光(OSL)、^(14)C等定年方法,对火山喷发序列进行综合研究,确定了喷发相对时序和绝对年龄。锡林浩特火山群火山活动具有周期性变化规律,其喷发序列由老到新依次为:上新世,早更新世,中更新世早期、中更新世晚期,晚更新世早、中、晚和末期,以及全新世,共9个火山喷发旋回。晚更新世是火山喷发的鼎盛时期。首次确定了鸽子山火山的最晚喷发年龄距今约6800年,为广义活火山。不同旋回火山喷发方式及火山风化降解程度差异较大。上新世为裂隙式喷发,早、中更新世主要是裂隙-中心式喷发,晚更新世以来为中心式喷发。中心式喷发火山类型有斯通博利型、夏威夷型、玛珥型和亚布里尼型,其中玛珥型火山在本区属首次发现。中更新世及以前的火山锥基本已剥蚀殆尽,晚更新世以来的火山地貌形态保存尚好。每个喷发旋回几乎都呈现从碱性玄武岩向拉斑玄武岩演化的特征,反映了本区深部岩浆房演化与构造活动强度的周期性变化规律。 展开更多
关键词 晚新生代 喷发序列 喷发类型 鸽子山活火山 锡林浩特
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琼北玛珥火山的结构特征及其对喷发历史和火山灾害的启示
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作者 何衍鑫 田伟 +4 位作者 刘平平 刘建平 崔亚圣 张朝鲲 许鑫 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第7期2103-2121,共19页
作为陆地和海岛上第二常见的火山类型,玛珥火山相关区域内生活着大约10%的世界人口,因此玛珥火山灾害研究具有重要科学意义。琼北地区发育的第四纪玛珥火山,是天然的研究对象。根据琼北地区卫星影像、数字高程模型和实地测量结果,确定... 作为陆地和海岛上第二常见的火山类型,玛珥火山相关区域内生活着大约10%的世界人口,因此玛珥火山灾害研究具有重要科学意义。琼北地区发育的第四纪玛珥火山,是天然的研究对象。根据琼北地区卫星影像、数字高程模型和实地测量结果,确定了11座玛珥火山的形态学特征。结果表明,琼北地区玛珥火山具圆形、椭圆形和三联点形三类平面形态,其面积0.01~3.42km2,周长0.43~6.64km,平均直径128~2128m,深度8~50m,喷出物体积(致密岩石当量,DRE)共计2.2km^(3),初始岩浆碎屑体积(DRE)共计1.7km^(3),爆炸能量1.2×10^(13)~6.4×10^(16)J,能量转换率则在1%~2%之间。玛珥火山活动可分成三期,第一期杨花岭、儒黄岭和那有岭的火山活动持续了6.35~0.11kyr;第二期陈永岭、石岭、罗经盘、玉墩岭和同类岭的火山活动持续了1.06~0.02kyr;第三期好秀岭、双池岭东岭和西岭的火山活动持续了仅16~0.3yr。石山-永兴一带的区域应力场控制着玛珥火山的拉伸方向。根据最新一期火山爆炸点的侧向迁移轨迹预测下一次爆炸点位于双池岭西岭向西约100~200m处。玛珥火山灾害类型多样,有地震、火山灰云、火山灰空落沉积、基浪涌流、火山弹和火山块喷射、火山泥流、火山气体和身体心理创伤等。喷发情景建模表明琼北火山喷发所产生的火山灰影响区域包括我国海南北部、广东和广西南部、台湾南部,以及越南东部,具体影响范围取决于喷发特征和实时气候。综上所述,我们制定了琼北火山灾害的危险性区划图,并建议对全国火山进行详细形态学调查,建立有代表性的典型案例,作为预测未来火山爆发、预防火山灾害的参考指南。 展开更多
关键词 玛珥火山 形态学 喷发历史 火山灾害 爆炸点迁移 琼北地区
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儿童抗癫痫药物所致重症药疹与HLA基因的关系
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作者 唐鲜艳 耿玲玲 +2 位作者 赵斯钰 温新然 李小青 《中国麻风皮肤病杂志》 2024年第7期461-465,共5页
目的:明确西北地区汉族儿童抗癫痫药物所致重症药疹与人类白细胞抗原(HLA)基因多态性的关联性。方法:收集2018年1月1日至2023年6月30日应用抗癫痫药物所致重症药疹的住院患儿20例为病例组,应用抗癫痫药物3个月以上未出现皮肤不良反应的... 目的:明确西北地区汉族儿童抗癫痫药物所致重症药疹与人类白细胞抗原(HLA)基因多态性的关联性。方法:收集2018年1月1日至2023年6月30日应用抗癫痫药物所致重症药疹的住院患儿20例为病例组,应用抗癫痫药物3个月以上未出现皮肤不良反应的患儿55例为耐受组,正常体检的40例儿童为正常对照组,采用序列特异性引物-聚合酶链反应法(PCR-SSP)检测外周血HLA-B^(*)1502、HLA-A^(*)2402、HLA-A^(*)3101 3个等位基因,分析等位基因分布频率在三组之间的差异。结果:重症药疹平均发病年龄(6.78±3.28)岁,平均潜伏期15天。三组总体基因分布频率有统计学差异(P<0.05)。病例组HLA-B^(*)1502等位基因分布频率与耐受组及正常对照组有统学差异(P<0.05),HLA-A^(*)2402及HLA-A^(*)3101基因分布频率在三组之间无统计学差异(P>0.05)。病例组HLA-B^(*)1502等位基因分布频率在卡马西平组与非卡马西平组有统计学差异(P<0.05)。结论:抗癫痫药物引发的重症药疹学龄前及学龄期儿童高发,潜伏期长。卡马西平所致重症药疹与HLA-B^(*)1502等位基因密切相关,建议患者服用抗癫痫药物前筛查HLA基因型,避免重症药疹的发生。 展开更多
关键词 癫痫 抗癫痫药物 重症药疹 人类白细胞抗原基因
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广东硇洲岛火山地质与射气岩浆喷发
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作者 王佳龙 成智慧 +1 位作者 丁冉 刘春茹 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第7期2122-2134,共13页
硇洲岛位于雷州半岛东部海域,该岛最具特征的火山喷发形式是发生在其东南部那晏湾的射气岩浆喷发,这也是揭开硇洲岛火山喷发历史、环境和过程的窗口。本文从硇洲岛火山地质、射气岩浆喷发基浪堆积物粒度分析、有机质稳定同位素分析、电... 硇洲岛位于雷州半岛东部海域,该岛最具特征的火山喷发形式是发生在其东南部那晏湾的射气岩浆喷发,这也是揭开硇洲岛火山喷发历史、环境和过程的窗口。本文从硇洲岛火山地质、射气岩浆喷发基浪堆积物粒度分析、有机质稳定同位素分析、电子自旋共振(ESR)测年等方法入手,分析讨论火山活动历史和射气岩浆喷发特征并追溯其基浪堆积物原始沉积环境。研究结果表明,早更新世强烈的岩浆溢流完成了岛屿的初始建造,之后硇洲岛高出海平面以上停止接受沉积;中更新世发生了两幕中小规模的火山活动,分别为距今约588ka的射气岩浆喷发和距今448ka的岩浆溢流;晚更新世在存亮湾附近可能发生了弱爆炸式火山喷发,自此硇洲岛的火山活动结束。 展开更多
关键词 硇洲岛 射气岩浆喷发 物源分析
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