大型火成岩破火山口的沉降诱发早期穹隆

Geology Pub Date : 2024-04-05 DOI:10.1130/g52130.1
Peter W. Lipman
{"title":"大型火成岩破火山口的沉降诱发早期穹隆","authors":"Peter W. Lipman","doi":"10.1130/g52130.1","DOIUrl":null,"url":null,"abstract":"Uplift at many well-documented resurgent calderas started only after completion of the associated ignimbrite eruption, but arching of the large Bachelor caldera in the Southern Rocky Mountain volcanic field, Colorado (USA), began during the eruption. A well-defined arched or domical structure, initiated within thickly accumulating ignimbrite as the caldera subsided, is documented by growth of keystone faults as the caldera filled, rheomorphism and local diapiric mobilization of early-erupted tuff, decreased dips in upper welding zones, and wedging of a late-erupted dacitic phase against flanks of the growing dome. Early subsidence-induced doming may have been triggered by preferential magma draw-down along ring-fault vents, relatively impermeable vesiculation and differential magma buoyancy centrally within the caldera, peripheral loading at caldera margins by landslides and talus from caldera walls, or some combination of factors. Early inception of caldera doming has implications for models of magma withdrawal and residual compositional gradients in non-erupted magma.","PeriodicalId":503125,"journal":{"name":"Geology","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Subsidence-induced early doming at a large ignimbrite caldera\",\"authors\":\"Peter W. Lipman\",\"doi\":\"10.1130/g52130.1\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Uplift at many well-documented resurgent calderas started only after completion of the associated ignimbrite eruption, but arching of the large Bachelor caldera in the Southern Rocky Mountain volcanic field, Colorado (USA), began during the eruption. A well-defined arched or domical structure, initiated within thickly accumulating ignimbrite as the caldera subsided, is documented by growth of keystone faults as the caldera filled, rheomorphism and local diapiric mobilization of early-erupted tuff, decreased dips in upper welding zones, and wedging of a late-erupted dacitic phase against flanks of the growing dome. Early subsidence-induced doming may have been triggered by preferential magma draw-down along ring-fault vents, relatively impermeable vesiculation and differential magma buoyancy centrally within the caldera, peripheral loading at caldera margins by landslides and talus from caldera walls, or some combination of factors. Early inception of caldera doming has implications for models of magma withdrawal and residual compositional gradients in non-erupted magma.\",\"PeriodicalId\":503125,\"journal\":{\"name\":\"Geology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-04-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Geology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1130/g52130.1\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Geology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1130/g52130.1","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0

摘要

许多有据可查的复燃火山口都是在相关的辉绿岩喷发结束后才开始抬升的,但美国科罗拉多州南落基山火山区的大贝克尔火山口在喷发期间就开始拱起。随着破火山口的下沉,在厚厚堆积的闪长岩中开始形成一个明确的拱形或圆拱形结构,破火山口的填充、早期侵蚀凝灰岩的流变形态和局部塌陷移动、上部焊接区的倾角减小以及晚期侵蚀的白云岩阶段与不断扩大的圆顶侧面的楔形,都证明了这一结构的形成。早期沉降引起的穹隆可能是由以下因素引发的:岩浆沿环状断层喷口优先向下汲取、相对不透水的裂隙和破火山口中央的岩浆浮力差异、破火山口边缘的山体滑坡和破火山口壁的滑石造成的外围荷载,或者是这些因素的某些组合。破火山口穹隆的早期出现对岩浆抽出模型和未喷发岩浆的残余成分梯度有影响。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Subsidence-induced early doming at a large ignimbrite caldera
Uplift at many well-documented resurgent calderas started only after completion of the associated ignimbrite eruption, but arching of the large Bachelor caldera in the Southern Rocky Mountain volcanic field, Colorado (USA), began during the eruption. A well-defined arched or domical structure, initiated within thickly accumulating ignimbrite as the caldera subsided, is documented by growth of keystone faults as the caldera filled, rheomorphism and local diapiric mobilization of early-erupted tuff, decreased dips in upper welding zones, and wedging of a late-erupted dacitic phase against flanks of the growing dome. Early subsidence-induced doming may have been triggered by preferential magma draw-down along ring-fault vents, relatively impermeable vesiculation and differential magma buoyancy centrally within the caldera, peripheral loading at caldera margins by landslides and talus from caldera walls, or some combination of factors. Early inception of caldera doming has implications for models of magma withdrawal and residual compositional gradients in non-erupted magma.
求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
自引率
0.00%
发文量
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信