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1.
五大连池老黑山、火烧山的火山喷发特征   总被引:1,自引:0,他引:1  
从野外调查及火山喷发观测记录入手, 结合国内外火山研究的新进展, 在火山成因类型、喷发方式及喷发前兆等方面讨论了五大连池老黑山、火烧山的火山喷发特征。指出老黑山、火烧山的火山成因类型属于单成因火山, 喷发方式不是简单的中心式喷发, 而是经历了裂隙式喷发后转为中心式喷发。通过火山喷发观测记录的分析及与国外火山对比, 揭示出此次火山喷发是有前兆的, 其前兆特征对监测预报未来火山喷发有借鉴意义。  相似文献   

2.
松辽盆地梨树断陷双龙地区白垩系火石岭组发育中心式和裂隙式两种喷发型火山,其在发育规模、油气成藏等方面存在不同。中心式喷发型火山活动剧烈,持续时间长,火山岩分布面积广,厚度大,岩性从基性火山岩逐渐向中性火山岩转变;裂隙式喷发型火山活动弱,持续时间短,火山岩分布面积小,厚度薄,岩性主要为中性火山岩。中心式喷发型火山与湖盆水体相邻,形成火山-湖泊沉积环境,火山岩、砂砾岩、深湖-半深湖泥岩交替沉积,使得中心式喷发型火山发育区的火石岭组具有良好的生、储、盖条件,并形成自生自储型生储盖组合方式;裂隙式喷发型火山远离湖盆水体,火山岩的分布与深湖相泥岩没有直接接触,加之储层物性差,因此裂隙式喷发型火山发育区的火石岭组油气成藏条件差。通过对研究区钻井、试油、地震等资料的综合分析认为,研究区西部中心式喷发型火山发育区是火石岭组有利的勘探区域,其烃源岩为深湖-半深湖泥岩,储集体包括火山碎屑岩、砂砾岩和火山岩,储集空间主要为裂缝和孔隙。  相似文献   

3.
刘祥  隋维国  向天元 《地质论评》1999,45(7):196-203
东北地区有4个活火山群,它们是长白山火山群 、五大连池火山群、龙岗火山群和镜泊湖火山群。这些活火山群中的活火山有潜在的喷发危险,一旦再次爆发,由火山喷发空中降落堆积物、火山泥流、火山碎屑流、火山碎屑崩塌和熔岩流等造成的灾害和环境污染将是巨大的。当务之急是重塑火山喷发历史和模式,编制火山灾害预测图。东北地区火山灾害类型如此之多,影响范围如此之广,进行专项火山灾害调查研究是必须的。  相似文献   

4.
Vulnerability Analysis in Earthquake Loss Estimate   总被引:1,自引:0,他引:1  
Yong  Chen  Qi-fu  Chen  Ling  Chen 《Natural Hazards》2001,23(2-3):349-364
The abodes in Costa Rica have almost the samevulnerability as the old civil houses in China, whichrepresent the vulnerability in worst cases. On theother hand, the high quality buildings in Middle Easthave the same vulnerability as the reinforced concretebuildings in China due to employing thestate-of-art-design and construction techniques, whichrepresent the vulnerability of the best cases. Themacroeconomic vulnerability is defined as the ratio ofphysical economic loss caused by earthquake to theGross Domestic Product (GDP) within a given area.Since the total macroscopic loss is the sum of lossesof different types of buildings and facilities, themacroeconomic vulnerability must be greater than thatof best cases while less than that of worst cases. Inthe present paper, the implications of macroeconomicvulnerability to earthquake loss estimate arediscussed.  相似文献   

5.
长白山天池火山喷发历史文献记载的考究   总被引:7,自引:2,他引:7  
金东淳  崔钟燮 《地质论评》1999,45(7):304-307
长白山天池火山是世界著名的火山之一,是我国规模最大、最具有潜在喷发危险的一座近代活动火山。除了距今大约1000 a前(据14C测年)此火山曾发生过特大规模喷发外,还多次发生规模不等的火山喷发。本文通过收集和查阅几千万字的文史古籍资料,进行整理、筛选、考证和分析,认为长白山天池火山于1018年、1124年、1200年、1265年、1373年、1401年、1573年、1668年、1702年和1903年多次喷发过。  相似文献   

6.
This paper is a partial discussion of a four-year study that investigated the vulnerability of the people living in the Cairns region to the tropical cyclone hazard. The longitudinal case study, focussing on the Cairns Northern Beaches area, was unique in that it included a social and societal `pre-cyclone impact' evaluation of various resident communities within the region, and then two consecutive `post-cyclone impact' studies. The primary research method supported an inductive qualitative approach to the collection and analysis of survey data. Some quantitative methods were invoked to support qualitative research findings. Survey data was collected in five separate questionnaire-based social surveys that were administered between 1996 and 2000. During the study, residents experiencedthe direct impact of two land-falling tropical cyclones. In addition to this, targeted andfocussed tropical cyclone awareness education was made increasingly available withinthe community. The social and demographic attributes that influence the individual'sperception of risk and contribute to our understanding of community vulnerability were examined and evaluated. Changes in the residents' attitudes, cyclone preparednessbehaviours and willingness to respond to cyclone warnings were monitored and measured. Analysis of early survey data indicated that community residents generally had some knowledge of cyclones but a limited understanding of cyclone processes and very little direct personal experience of the cyclone hazard. Individually and collectively, residents frequently demonstrated a biased perception of the risks associated with cyclones. The resident community was shown to be fragmented, with limited support being available to individual households. Initially, residents were found to be poorly prepared for cyclones and unlikely to respond to warnings appropriately. It appeared that, in the event of a land-falling tropical cyclone impacting the area, the community was highly vulnerable to unnecessary loss of property, livelihood and – in extreme circumstances – life. By 2000, Cairns community residents were somewhat better informed about cyclones and certainly more experienced. This paper provides some insight into how cyclone experience and education may synergisticly have contributed to a change in risk perceptions and a reduction in the vulnerability of Cairns residents to the tropical cyclone and storm surge hazards.  相似文献   

7.
本文综述了最近几年来中国研究者在地热流体地球化学研究领域取得的主要进展。在国际上关于地球内部流体及其作用研究取得重要进展的大背景下,我国学者在地热流体地球化学研究上也取得了一些重要成果,主要表现在火山地热区和非火山地热区两大方面,在火山学、地热学、环境学、大地构造学、地震学等五个学科领域都取得了一些重要进展。  相似文献   

8.
Tsunamis have occurred in Canada due to earthquakes, landslides, and a large chemical explosion. The Pacific coast is at greatest risk from tsunamis because of the high incidence of earthquakes and landslides in that region. The most destructive historical tsunamis, however, have been in Atlantic Canada – one in 1917 in Halifax Harbour, which was triggered by a catastrophic explosion on a munitions ship, and another in 1929 in Newfoundland, caused by an earthquake-triggered landslide at the edge of the Grand Banks. The tsunami risk along Canada's Arctic coast and along the shores of the Great Lakes is low in comparison to that of the Pacific and Atlantic coasts. Public awareness of tsunami hazard and risk in Canada is low because destructive tsunamis are rare events.  相似文献   

9.
吴越  刘东升  陆新  宋强辉 《岩土力学》2011,32(8):2487-2492
承灾体易损性定量评估是制约滑坡灾害风险评估研究的瓶颈问题。为此,以滑坡体冲击冲量为致灾强度指标、建筑物整体抗剪力为抗灾性能指标,推导出典型承灾体易损性定量评估模型。在此基础上,考虑滑体运动特征参数随机性对易损性的影响,提出风险曲线和最大风险度指标的概念,以反映滑坡灾害成灾全过程中不确定性对灾害后果的影响。并采用该模型分析了坡体几何特征参数、受灾体空间位置以及受灾体抗灾性能对易损性的影响规律。将风险度指标应用于算例分析,并与以往方法进行了比较,分析发现,建立的易损性定量评估模型可以反映二维简化情况下受灾体毁损程度与各种影响因素之间关系的基本规律,为易损性定量评估提供了一种途径。  相似文献   

10.
11.
Potential Hazards of Eruptions around the Tianchi Caldera Lake, China   总被引:8,自引:0,他引:8  
Since the eruption of the Tianchi volcano about 1000 years ago, there have been at least 3 to 5 eruptions of small to moderate size. In addition, hazardous avalanches, rock falls and debris flows have occurred during periods between eruptions. A future eruption of the Tianchi volcano is likely to involve explosive interaction between magma and the caldera lake. The volume of erupted magma is almost in a range of 0.1-0.5 km3. Tephra fallout may damage agriculture in a large area near the volcano. If only 1% of the lake water were ejected during an eruption and then precipitated over an area of 200 km2, the average rainfall would be 100 mm. Moreover, lahars are likely to occur as both tephra and water ejected from the caldera lake fall onto flanks of the volcano. Rocks avalanching into the caldera lake also would bring about grave hazards because seiches would be triggered and lake water with the volume equal to that of the landslide would spill out of the existing breach in the caldera and cause flooding  相似文献   

12.
13.
刘祥  郎建军 《地质论评》2011,57(5):650-658
黑龙江五大连池世界地质公园的老黑山、火烧山火山岩屑崩落(debris-avalanche)形成小丘状沉积.老黑山火山西面、东面和东南面有数十座小丘,火烧山火山北面和东北面也有数十座小丘.最大的小丘高约17m,基座直径50m以上.最远的小丘距火山2km.小丘为崩落堆积的岩块相,由巨大的崩落岩块组成.崩落岩块为灰紫色玄武质...  相似文献   

14.
长白山火山历史上最大火山爆发火山碎屑物层序与分布   总被引:11,自引:0,他引:11  
长白山火山历史时期规模最大的火山喷发发生在1199~1200年。这次大爆发分为两次普林尼(Plinian)式喷发:第一次(早期)喷发称赤峰期,第二次(晚期)喷发称园池期。赤峰期喷发模式为:普林尼式喷发柱(赤峰空落浮岩层)—火山碎屑流(长白火山碎屑流层)—火山泥流(二道白河火山泥流层),主要由火山碎屑流诱发火山泥流;园池期火山喷发模式为:普林尼式喷发柱(园池空落浮岩火山灰层)—火山碎屑流(冰场火山碎屑流层)。两次普林尼式喷发空落火山碎屑物总量约120 km3,长白火山碎屑流层总量约8 km3,冰场火山碎屑流层总量约0.5 km3,火山泥流堆积总量约为2 km3。主要论述了这次大爆发的火山喷发碎屑堆积物的层序和分布。  相似文献   

15.

广西北海涠洲岛是我国最大的第四纪火山岩海岛。近些年来随着我国核电事业的不断发展,涠洲岛火山最后喷发时代和对区域核电厂址的潜在火山灾害,受到了国内外地学界和核电工业界的广泛关注。我们通过对涠洲岛南部地区射汽岩浆喷发的基浪堆积物的野外地质地貌考察,研究了火山喷发物的岩性特征、沉积结构和堆积规模。同时,对系统采集于不同堆积部位的喷发物样品和上覆的黄土样品进行了电子自旋共振(ESR)年代测试分析,结合前人光释光(OSL)测年结果,得出涠洲岛火山最后一次喷发的时间为晚更新世晚期至全新世早期,距今约13~33ka。

  相似文献   

16.
魏海泉  陈正全 《地质论评》2022,68(3):2022052008-2022052008
洪加(Hunga)火山位于新西兰—克马德克—斐济俯冲带,该火山于2021年末又开始活动,并在2022年1月14、15日发生了千年一遇的世纪大喷发。喷发柱穿进平流层,形成了一个最高30 km、最宽800 km的蘑菇云,后期的气体火山灰云团几乎环绕南半球一周。喷发所引起的海啸在太平洋沿岸多地造成了灾害。根据现有的资料分析,洪加火山岩浆成分以安山岩为主,岩浆可能是沿着破火山口边缘由富气岩浆团块的“渗漏”驱动喷发的。这次洪加火山大喷发的一个最重要特征是喷发时产生了极为强烈的大气冲击波,这代表了岩浆内火山气体的极大富集。正是这种“超级富气岩浆”的喷发在喷火口位置形成了远超0.1 MPa(1 标准大气压)的出口压强,引发了向全球辐射的冲击波和数千千米以外都能听到的喷发声响。本次火山喷发引发海啸的机制,其一是爆炸冲击波,向外扩张的冲击波推动了海面表层海水的向外扩张;其二是苏特塞式(Surtseyan)喷发本身就有向外排走海水的能力。未来洪加火山喷发形式,很可能是沿着破火山口周边断裂或靠近破火山口中央谷地的熔岩穹丘或熔岩流。苏特塞式喷发会比较常见,但喷发规模不会太大。  相似文献   

17.
长白山天池火山晚更新世以来的喷发活动:   总被引:6,自引:0,他引:6  
应用高精度铀系不平衡TIMS法测定了吉林长白山天池火山岩锥体中上部的11个熔岩、浮岩样品的年龄,并据此划分出晚更新世、全新世以来6个喷发活动期次,分别为:>350ka、70ka、18-25ka、10ka、4-5ka和1-0.75ka。此外,还介绍了铀系不平衡法火山岩年代学的基本原理和试验流程,讨论了样品封闭等问题。  相似文献   

18.
中国西北水资源的脆弱性   总被引:8,自引:3,他引:8  
刘春蓁 《冰川冻土》2003,25(3):309-314
The vulnerability of water resources in Northwest China were described in terms of the sensitivity and adaptability of water resource systems effected by climate change and human activities. Most measures that reduce the vulnerability are closely linked with decreasing the sensitivity of climate change or human activity. In other words, the interaction of climate factors and human activity may either exacerbate or mitigate the vulnerability of water resources. Studying both positive and negative events in terms of sustainable utilization of water resources in the past, may establish the sound strategic base in regulating further human activity. The knowledge and correct awareness of recent and future tendencies of hydro-climatic condition may serve as an imperative scientific base for taking such actions as: 1) undertaking structural and non-structural (e.g., policy, law, and forecasting) measures in a reasonable way; 2) coordinating and allocating both differences of time and space between inflow water and water use and between water yield area and water assumption area as well.  相似文献   

19.
The examination of the Main Pugachevo gas-water-lithoclastic volcano during the summer of 2005 and GPS-controlled large-scale (1: 1000) mapping revealed its regular but rather peculiar eruption. It was the largest among the eruptions investigated since 1911 and produced a very unusual lithoclastic field with an area of about 100 000 m2 and a volume of about 100 000 m3. The eruption occurred from three distinct active centers and began with a vigorous explosion-like gas burst from one center followed by the noncontemporaneous discharge of a gas-and water-saturated liquid lithoclastic mass from the three centers, which produced a number of flows of different directions and sizes. The flows almost completely covered the smoothed flat open area of the volcano and even invaded the larch forest surrounding the volcano, where they bent, overturned, broke, and occasionally uprooted and dragged over some distance some large trees. The analysis and comparison with all the previously documented eruptions of the Main Pugachevo gas-water-lithoclastic volcano revealed their fairly diverse, sometimes strongly variable character with respect to many parameters: the amount of ejected lithoclastic material; the number of eruption centers; and the proportions of the erupted gaseous, liquid, and solid components. In general, the eruptions show a distinctly multirank periodic character: relatively minor or small low-rank eruptions take place once every 1–2 yr, and large eruptions of a higher rank are much less frequent (supposedly, once in 70 years).  相似文献   

20.
张家口中生代火山盆地火山喷发对古气候的影响   总被引:5,自引:0,他引:5  
郭正府  刘嘉麟 《岩石学报》1998,14(3):318-331
本文在详细地研究了张家口中生代火山盆地火山喷发物的基础上,利用岩石学及大气环境化学的基本原理,提出了一套系统估算火山喷出气体及气溶胶总量的程序与方法,并对张家口中生代火山喷出气体的种类、总量及气溶胶总量进行了估算;分析了火山硫化物气体转化为火山硫酸盐气溶胶的光化学过程及可能途径。在分别研究了本区火山喷发导致的“阳伞效应”与“温室效应”的基础上,探讨了该区火山喷发对地表温度的综合影响。初步结果表明:张家口中生代火山盆地火山喷发向当时大气圈中输送了约9.96×1010kg的硫酸盐气溶胶,它们能导致当时北半球范围内太阳总幅射率降低0.81%~3.60%,最终造成地表温度下降约0.81℃~3.6℃。  相似文献   

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