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由中国地震局监测预报司主办、中国地震局地质研究所、吉林省地震局和长白山科学研究院承办的长白山火山研讨会于2006年8月28日至31日在吉林省二道白河市新落成的国家野外科学观测研究站———长白山天池火山观测试验站举行。来自中国科技部、中国地震局、中国科学院、高等院校、国土资源部等20余个单位的共70余名代表出席了会议。这是一次全国范围内活动火山监测与研究的盛会,丁国瑜、邓起东和刘嘉麒3位院士参加了会议,并做了重要发言。会议期间代表们考察了中国规模最大和最具潜在喷发危险性的天池火山口,天池巧夺天工的火山地貌给大家留下了十分深刻的印象。长白山地处中国东北的东部和朝鲜北部,主峰海拔2691米,为东北最高峰。位于主峰之颠的天池及其附近的十几个火山群,构成了规模庞大的火山系统,是目前中国境内保存最为完整的新生代多成因复合火山,被认为是世界上最具潜在喷发危险性的火山之一。据地震部门监测,2002年下半年以来长白山火山出现了震群活动,火山活动呈现出趋于活跃的态势。为了交流火山监测与研究的经验,探讨中国大陆火山活动的趋势、火山未来喷发的危险性、火山活动在现今构造活动中的意义,减轻火山重新活动可能带来的灾害,本次会议以“火山活动 相似文献
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腾冲火山地质研究述评 总被引：7，自引：0，他引：7
在综合分析前人有关腾冲火山研究成果的基础上，对该区火山活动的研究现状，火山活动特征，火山活动背景及火山活动与深部岩浆侵入活动的关系等进行了评述。认为腾冲火山群中存在全新世活火山，现今处于休眠状态，具有再次喷发的潜在危险性，因此，进一步深入研究腾冲火山在全新世活动的时间分布规律，对于在该区开展火山活动监测，减灾防灾等方面具有重要意义。 相似文献
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根据火山喷发实例总结了火山喷发在不同阶段的活动状态,并探讨了可能的物理机理。火山活动从岩浆补给到岩浆喷发的物理过程可分为3个阶段:1)岩浆补给阶段,岩浆囊压力差或过剩压力的大小决定了火山活动是否休眠或扰动,岩浆补给速率对压力差起了决定性的作用;2)通道形成阶段,当过剩压力超过围岩破裂强度时,围岩开始破裂,之后水热活动起了重要的作用;3)岩浆运移与失稳喷发阶段,主要是岩浆运移与地壳盖层的相互作用与失稳的过程。文中还讨论了火山活动状态与火山喷发危险性等级之间的关系,7个危险性等级分别对应于火山活动的7种状态,即休眠、平静、扰动、动荡、临界、活动、灾变 相似文献
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长白山天池火山潜在喷发危险性讨论 总被引：3，自引：0，他引：3
根据吉林省新生代以来火山喷溢活动的时空演化历史，特别是全新世以来火山活动频民强度变化特征，以及现代喷发活动史记资料，结合１０多年火山动态观测数据，讨论了长白山天池潜在喷发的危险程度，认为其灾害性潜在喷发危险的时间尺度仍属于地质范畴。 相似文献
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通过对2016年全球活动火山监测信息的统计，2016年共有96座火山记录到喷发活动，主要分布在环太平洋俯冲带及印度板块与欧亚板块碰撞边界上。火山预警等级共有4个，可以标识火山的危险程度，本文根据火山每个预警等级在全年52次监测信息报道中的出现次数，将96座活动火山按危险程度划为4类，并对每类的火山活动作出了详细描述。2016年的火山喷发也造成了人员伤亡和财产损失，印度尼西亚是受火山灾害影响最严重的国家。此外，根据火山灰柱海拔高度的整理及近年活动火山数量的调查，推测2016年的火山活动仅会使火山附近区域的天气受到影响，应不会引起全球性的气候异常。 相似文献
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《地球物理学进展》2016,(5)
长白山火山是一座具有潜在喷发危险的大型近代活动火山,因此通过对该火山活动的监测,加强对长白山天池火山岩浆系统的研究并了解天池火山的活动性质是很有意义的.除了开展长白山火山活动历史、火山地层学、火山岩岩石学、年代学以及火山地质等研究之外,我国从20世纪80年代开始在该火山区域进行了一系列的地球物理探测活动.为深入了解长白山火山区岩浆的分布与活动特征,本文对前人工作进行总结,得到了关于长白山火山活动的以下几个方面的认识:1)通过火山区地震活动性监测得到了火山区的岩浆活动状态;2)利用大地电磁测深对火山区地下是否存在可能再次活动的岩浆囊及其分布形态进行监测,为火山喷发的危险性预测和灾害评价提供依据;3)利用人工源深地震测深对长白山天池及其邻域的结晶基底及地壳精细结构进行讨论;4)利用天然地震对火山区地壳、上地幔结构进行深入研究,分析了与火山区有关的深层动力学因素;5)对国外火山区重力监测实例的调研表明,重力监测对了解岩浆活动状态是十分有效的手段.多种地球物理方法的综合应用,获得了长白山火山地区地壳至地幔转换带的详细资料. 相似文献
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归纳总结2017年度全球81座活火山的活动情况，共计活动1058座次，平均每周记录20座活火山的活动信息。根据火山潜在喷发的危险性和火山活动的强弱程度对上述火山进行分级描述，火山活动主要反映了地球表层的构造活动，其中大角度俯冲带的弧后火山最为强烈，小角度的俯冲带、拉张裂谷和走滑为主的板块边界火山活动较为平静，火山活动频繁的印度尼西亚岛链是受灾最为严重的区域。预计全球火山活动将进一步加剧，印尼岛链受火山灾害威胁的程度依然较大。位于印尼岛链巴厘岛上的阿贡火山自2017年9月开始活动以来，整个喷发过程极具代表性，监测阿贡火山喷发过程可为全球典型火山喷发事件研究提供参考。 相似文献
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国外火山减灾研究进展 总被引：4，自引：1，他引：3
概述了国外近期火山灾害减轻进展,内容包括：火山灾害分类,识别高危险性火山,灾害识别、评价和分带,火山监测和喷发预测。减轻火山灾害的工程措施以有火山应急管理等方面。并对几次重大火山喷发灾难实例作了介绍和分析比较 相似文献
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More than 40 late Cenozoic monogenetic volcanoes formed a volcanic belt striking NNW from Keluo, through Wudalianchi to Erkeshan in NE China. These volcanoes belong to a unified volcano system, namely Wudalianchi volcanic belt(WVB for short). Based on the volcanic evolution history and the nature of monogenetic volcanic system, we estimate that the volcanic system of WVB is still active and has the potential to erupt again. Hence, this paper studied the temporal-spatial distribution and volcanic eruption types to evaluate the possible eruption hazard types and areas of influence in the future.
Volcanic field characteristics and K-Ar radiometric data suggest two episodes of volcanism in the WVB, the Pliocene to early Pleistocene volcanism(4.59~1.00MaBP)and the middle Pleistocene to Holocene volcanism(0.79Ma to now). The early episode volcanoes are distributed only in the north of WVB(mainly in Keluo volcanic field), featured by effusive eruption, and mainly formed monogenetic shield, whose base diameter is large and slope is gentle. However, the late episode eruptions occurred over the entire WVB. The explosive eruption in this stage formed numerous relatively intact scoria cones of explosive origin. Meanwhile the effusive eruption formed widely distributed lava flows.
Both effusive eruption and explosive eruption are common in WVB. The effusive eruption formed monogenetic shields and lava flows. The resulting pahoehoe lava, aa lava and block lava appeared in WVB. There are three end-member types of explosive eruption driven by magmatic volatile. Violent Strombolian eruption has the highest degree of fragmentation and mass flux, characterized by eruption column. Strombolian eruption has the high degree of fragmentation, but low mass flux, featured by pulse eruption. Hawaiian eruption has low degree of fragmentation, but high in mass flux, generating large scoria cones. In addition, this paper for the first time found phreatomagmatic eruption in WVB, which formed tuff cone. Transitional eruptions are also common in WVB, which have certain characteristics among the end-member eruption types. Besides, certain volcanoes displayed multiple explosive eruption types during the whole eruption span.
According to the volcanic temporal-spatial distribution and eruption characteristics in WVB, the potential volcanic hazards in future are constrained. It appears that the violent Strombolian and Strombolian eruption will not have significant impact on aviation safety in the vertical direction. In the radial direction, the ejected volcanic bomb can reach as far as 1km from the vents and the fallout tephra may disperse downwind over a distance ranging from 1~10km. The major hazard of Hawaiian eruption and effusive eruption comes from lava flow, and its migration distance may reach 3.0~13.5km for pahoehoe lava and 2.9~14.9km for aa lava. The base surge in phreatomagmatic eruption can reach a velocity of 200~400m/s, and the migration distance is around 10km. This is a big threat that people should pay more attention to and take precautions in advance. Besides, it is necessary to strengthen the real-time observation of the volcanoes in the WVB, especially those formed in the late episode as well as near the active fault. 相似文献
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中国大陆火山监测研究进展 总被引：4，自引：2，他引：4
吴建平 《地震地磁观测与研究》2005,26(5):1-10
在过去几年里，长白山天池火山观测到了明显的地震活动增加、地表抬升和膨胀以及多种流体化学异常。地震学研究和形变模拟表明，长白山天池火山近年来的活动可能是由其下方的岩浆活动引起的。1993年以来，腾冲火山出现强烈的水热活动。地球化学参数的变化表明，气体源区的深度逐渐增加。火山区存在的震群活动、部分台站观测到的S波阴影区以及地表的缓慢抬升等，指示火山区存在一个岩浆系统。监测研究结果表明，目前我国大陆其他火山的活动性较弱。 相似文献
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El Chichón volcano is an andesite stratovolcano in southern México. It erupted in March 1982, after about 550 years of quiescence. The 1982 eruption of El Chichón has not been followed by the growth of a lava dome within the newly formed crater. This is rather anomalous since the construction of a new dome after the destruction of an old one is a common process during the eruptions at andesite and dacite volcanoes. To discuss this anomalous aspect of the El Chichón eruption, some regularity in the process of re-awakening of dormant (here defined as a period of quiescence of more than 100 years) andesite and dacite volcanoes are studied based on the seismic activity recorded at the volcanoes Bezymianny, Mount St. Helens, El Chichón, Unzen, Pinatubo and Soufrière Hills. Three stages were identified in the re-awakening activity of these volcanoes: (1) preliminary seismic activity, leading up to the first phreatic explosion; (2) activity between the first and the largest explosions; (3) post-explosion dome-building process. The eruptions were divided into two groups: low-VEI (Volcanic Explosivity Index) and the long duration stage-1 events (Unzen, 1991 and Soufrière Hills volcano, 1995) and high-VEI and the short duration stage-1 events (Bezymianny, 1956; Mount St. Helens, 1980; El Chichón, 1982 and Pinatubo, 1992). The comparative analysis of the seismo-eruptive activity of two eruptions of the second group, the 1980 of Mt. St. Helens and the 1982 of El Chichón, produced an explanation the absence of new dome building during the 1982 eruption of El Chichón volcano. It may be explained in terms of the unusually rapid emission of gas and water from the magmatic and hydrothermal system beneath the volcano during a relatively short sequence of large explosions that could have sharply increased the viscosity of the magma making impossible its exit to the surface. 相似文献
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The 1995–1996 eruption of Mt. Ruapehu has provided a number of insights into the geochemical processes operating within the magmatic-hydrothermal system of this volcano. Both pre-eruption degassing of the rising magma and its eventual intrusion into the convective zone of the hydrothermal system beneath the lake were clearly reflected in lake water compositions. The eruptions of September–October 1995 expelled the lake, and provided the first-ever opportunity to characterise gas discharges from this volcano. The fumarolic discharges revealed compositions typical of andesite volcanoes and strong interaction with the enclosing meteoric and hydrothermal system fluids. Some 1.1 MT of SO2 gas was released from the volcano between September 1995 and December 1996, whereas ca. twice this amount (2.2 MT equivalent SO2) was erupted as soluble (i.e. leachable) oxyanions of sulphur. Significantly more sulphur was released from the volcano over this period than can be accounted for from the magma volume actually erupted. The evidence suggests that a sizable component of the evolved sulphur was remobilised from the long-lived hydrothermal system within the volcano during the 1995–1996 activity. 相似文献
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PRELIMINARY VOLCANIC HAZARD ZONATION IN JINLONGDINGZI VOLCANO,LONGANG VOLCANO AREA,JILIN PROVINCE,CHINA 
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下载免费PDF全文 Longgang volcano cluster is 150km away from the Tianchi volcano, located in Jingyu and Huinan Counties, Jilin Province, China. It had a long active history and produced hundreds of volcanoes. The latest and largest eruption occurred between 1 500 and 1 600 years ago by Jinlongdingzi(JLDZ)volcano which had several eruptions in the history. This paper discusses the volcanic hazard types, and using the numerical simulations of lava flow obtained with the Volcflow model, proposes the hazard zonation of JLDZ volcano area. JLDZ volcano eruption type is sub-plinian, which produced a great mass of tephra fallout, covering an area of 260km2. The major types of volcanic hazards in JLDZ area are lava flow, tephra fallout and spatter deposits. Volcflow is developed by Kelfoun for the simulation of volcanic flows. The result of Volcflow shows that the flows are on the both sides of the previous lava flows which are low-lying areas now. According to the physical parameters of historical eruption and Volcflow, we propose the preliminary volcanic hazard zonation in JLDZ area. The air fall deposits are the most dangerous product in JLDZ. The highly dangerous region of spatter deposits is limited to a radius of about 2km around the volcano. The high risk area of tephra fallout is between 2km to 9km around the volcano, and between 9km to 14km is the moderate risk area. Out of 14km, it is the low risk area. Lava flow is controlled by topography. From Jinchuan Town to Houhe Village near the volcano is the low-lying area. If the volcano erupts, these areas will be in danger. 相似文献
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阿什库勒盆地位于NE向阿尔金断裂与NW向康西瓦断裂的"弧形"交会处,构造活动十分活跃,盆地内发育10余座火山,其中阿什火山为该火山群中最新活动的火山。文中从火山地质、熔岩和斑晶成分、显微结构特征及地质温压计4个方面对阿什火山进行了详细研究。结果表明,阿什火山由火山锥和熔岩流组成,锥体由早期的渣锥和晚期的溅落锥组成,熔岩流分布面积约33km2,可划分为4个流动单元。熔岩属于钾玄岩系列,岩性为粗安岩,显微镜下呈斑状结构。斑晶以长石(主要为中长石)和辉石(包括普通辉石、古铜辉石和紫苏辉石)为主;基质为玻璃质、隐晶质、微晶质,部分含有大量的长石和辉石。斑晶与岩浆的平衡温度为1 104~1 194℃,压力为570~980MPa,对应的岩浆房深度为18.92~32.29km。 相似文献
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科洛火山群的新生代火山共有23座,坐落于科洛河两岸,火山岩面积约为350km2,岩性主要为碱性玄武岩.由于地处NE向断陷盆地这一特殊的构造位置,科洛地区的火山活动及展布主要受到区域基底断裂的制约.火山喷发形式总体为中心式,属斯通博利式火山.火山活动可划分为上新世、更新世和全新世3期.上新世在断陷盆地边缘形成了一系列NE向线性展布的中心式溢出型火山,其中部分火山因风化剥蚀而失去了原有的火山地貌特征,仅保留盾形熔岩台地.早更新世火山活动相对平静.中-晚更新世火山活动仍受到NE向基底断裂的控制,但喷发中心、喷发方式及喷发强度均发生改变,火山由碱玄质火山渣锥和熔岩流组成.进入全新世以后南山喷发,其火山结构保存完好,裸露的熔岩台地保留了较好的微地貌特征.该期火山亦由碱玄质火山渣锥和熔岩流构成.在科洛火山群的火山活动过程中,其熔岩流覆盖了早期沉积地层,并对盆地中的河流进行了改造,最终导致该区断陷盆地初始地貌的改变. 相似文献
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Hideo Hoshizumi Kozo Uto Kazunori Watanabe 《Journal of Volcanology and Geothermal Research》1999,89(1-4)
During the past 500 thousand years, Unzen volcano, an active composite volcano in the Southwest Japan Arc, has erupted lavas and pyroclastic materials of andesite to dacite composition and has developed a volcanotectonic graben. The volcano can be divided into the Older and the Younger Unzen volcanoes. The exposed rocks of the Older Unzen volcano are composed of thick lava flows and pyroclastic deposits dated around 200–300 ka. Drill cores recovered from the basal part of the Older Unzen volcano are dated at 400–500 ka. The volcanic rocks of the Older Unzen exceed 120 km3 in volume. The Younger Unzen volcano is composed of lava domes and pyroclastic deposits, mostly younger than 100 ka. This younger volcanic edifice comprises Nodake, Myokendake, Fugendake, and Mayuyama volcanoes. Nodake, Myokendake and Fugendake volcanoes are 100–70 ka, 30–20 ka, and <20 ka, respectively. Mayuyama volcano formed huge lava domes on the eastern flank of the Unzen composite volcano about 4000 years ago. Total eruptive volume of the Younger Unzen volcano is about 8 km3, and the eruptive production rate is one order of magnitude smaller than that of the Older Unzen volcano. 相似文献