搜索结果: 16-30 共查到“知识库 火山学”相关记录233条 . 查询时间(0.375 秒)
中国北方有着众多新生代以来形成的火山群，为研究火山锥降解问题提供了良好条件。文章通过３０ｍ精度ＤＥＭ统计
了来自五大连池、柴河—阿尔山、诺敏河—奎勒河、新疆阿什库勒、大同五个火山群共４０座火山的锥体形态学参数Ｈｃｏ与Ｗｃｏ
值，并搜集了对应的锥体年代学数据对火山锥的降解过程开展研究。获得的主要认识如下：（１）对火山锥进行了Ｈｃｏ／Ｗｃｏ—年
龄分组，结果显示在五个火山群中具有实际喷发年龄的４...
日本樱岛火山灰玻璃碎屑形态特征研究
火山玻璃 表面形态 表面结构 日本樱岛
2018/4/12
火山灰年代学是控制地层年代最简单可靠的直接手段，近年来在磁性地层、构造演化和古气候环境、考古等研究中被广泛重视和应用，经常成为最关键的要素。然而对其在地层中的识别常常产生较大分歧，制约了对年代的控制及与此相关的许多科学问题的解决。火山玻璃作为火山灰中的常见和标签物质，是识别火山灰最直接可靠的材料。日本强烈的第四纪火山活动和清晰连续的火山灰沉积在这方面具有代表性。本文利用光学显微镜和扫描电镜，对日本...
文中从各类岩石磁化率、密度统计数据出发，对比分析不同地层和岩性的磁性、密度，指出在研究区内开展火山岩重磁研究具有有利的物性基础。在利用带通滤波方法对重磁异常进行位场分离，消除沉积盖层和区域场影响后，获得由火山岩引起的剩余重磁异常，位场分离结果显示，反映火山岩的局部重磁异常多呈串珠状NE向分布。同时采用水平总梯度和垂向导数等边界信息增强手段，圈定研究区内的断裂构造分布情况，划分出了4条向SE弧形突出...
黑龙江省黑河地区广泛发育侏罗-白垩纪火山岩，但是该火山岩的岩石组合、成因和所表征的大地构造环境目前有很大的争议。本文对该套火山岩开展详细的岩石学、岩石地球化学等研究。该火山岩形成于早白垩世，主要以安山岩英安岩流纹岩为主，包含英安岩、安山岩、粗面岩、流纹岩、安粗岩、玄武安山岩、粗面英安岩、钾玄岩、歪长粗安岩，因此属于弧火山岩的组合。该区火山岩主要为亚碱性系列，岩石Na2O/K2O比值一般>1.2。A...
火山渣锥是白头山（或长白山）火山喷发的重要产物，主要沿熔岩台地周边呈圆锥状寄生小火山锥体分布。野外特征显示，火山渣是火山渣锥的重要组成；岩石手标本显示，火山渣具有气孔构造，样品自顶部至底部，颜色从赤色、赤褐色，向褐色、灰色发生转变。地球化学特征表明，火山渣岩性包括玄武岩、粗面玄武岩、玄武岩质粗面安山岩、粗面安山岩岩，具有较高SiO2（46.22%~55.38%），Al2O3含量（15.28%~22...
火山地层界面的储层意义——以松辽盆地南部火石岭组为例
喷发不整合界面 界面控储 储层意义
2016/5/17
基于岩心、薄片、物性及核磁测井T2谱等资料,从盆地火山地层界面分类及测井识别入手,开展火山地层界面与储层分布关系的研究,探讨了火山地层界面的控储机理。松南王府断陷火石岭组火山地层界面可划分为2级3类:喷发间断不整合界面构成一级界面,喷发整合和喷发不整合界面构成二级界面。火山地层界面与储层关系密切,距喷发间断不整合界面越近,储层物性越好,反之则越差,优质储层往往发育在喷发间断不整合界面之下30 m之...
Simultaneous determination of 58 major and trace elements in volcanic glass shards from the INTAV sample mount using femtosecond laser ablation-inductively coupled plasma-mass spectrometry
volcanic glass tephra LA-ICP-MS element abundance femtosecond lasert
2017/4/10
Four volcanic glass samples on the INternational focus group on Tephrochronology And Volcanism (INTAV) sample
mount described by Kuehn et al. (2011) were analyzed to establish a new methodology for m...
Indication of hydrothermal deposits and ore area on caldera floor and shallow sub-seafloor of the Bayonnaise knoll, based on high-resolution acoustic investigation
hydrothermal deposits high-resolution acoustic observation AUV sub-seafloor SBP
2017/4/10
The Bayonnaise knoll, an active submarine volcano belonging to an actively rifted part of the Izu-Bonin volcanic arc,
exhibits hydrothermal ore deposits on its caldera floor in a region known as the ...
Stress tensor computations at Mount St. Helens (1995-1998)
Mount St. Helens (USA) fault-plane solutions inversion stress field
2015/9/29
Fault plane solutions of 459 events occurring between 1995 and 1998 at Mount St. Helens (State of Washington, Northwest U.S.A.) were considered in order to infer the state of stress beneath the volcan...
An integrated magnetotelluric study of the Mt. Etna volcanic structure
Magnetotellurics Mt. Etna Volcanic structure feeding system
2015/9/28
he results of a magnetotelluric (MT) survey performed at Mt. Etna (Sicily, Italy) are presented and discussed.
The MT interpretation is preceded by the description of the data managing strategy used ...
New magnetotelluric soundings in the Mt. Somma-Vesuvius volcanic complex: preliminary results
Magnetotellurics volcanology crustal explorations Mt. Somma-Vesuvius
2015/9/28
During 1997 ten magnetotelluric (MT) soundings were recorded in single-site mode above the Mt. Somma-Vesuvius volcanic area. A first campaign of MT measurements was carried out, during spring, by the ...
Application of electric and electromagnetic methods to the definition of the Campi Flegrei caldera (Italy)
applied geophysics electric and electromagnetic methods campi flegrei caldera
2015/9/28
The results of an analysis of Dipolar Geoelectrical (DG), Magnetotelluric (MT) and Self-Potential (SP) data
collected over the emerged portion of the Campi Flegrei (CF) caldera (South Italy) are pres...
Temperature distribution analysis of July 2001 Mt. Etna eruption observed by the airborne hyperspectral sensor MIVIS
remote-sensing volcano monitoring thermal infrared dual-band technique
2015/9/17
On 17th and 18th July 2001, several fractures opened on Mt. Etna southern flank generating different lava flows
spreading both in Valle del Bove and towards Nicolosi. On 29th July the image spectrome...
Radon, water chemistry and pollution check by volatile organic compounds in springs around Popocatepetl volcano, Mexic
soil radon water chemistry volcanic activity
2015/9/10
Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country
is settled. Radon in the soil and groundwater together with water chemistry fr...
Water chemistry and soil radon survey at the Poas volcano (Costa Rica)
Poas volcano geochemistry radon precursor
2015/9/10
Radon-in-soil monitoring at the Poas volcano (Costa Rica) has been performed together with water chemistry
from the hot crater lake since 1981 and 1983 respectively. The results are discussed as a fu...