Structure and eruptive mechanisms at Surtsey Volcano, Iceland
Abstract Glassy basalt tuff was the primary material cored in 1979 from a 181 m deep drill hole on the east tuff ring of Surtsey volcano. Despite the fact that the hole extends 122 m below sea level all the core is similar to the exposed tephra composing the two tuff rings of the island. The tuff in...
Published in: | Geological Magazine |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
1985
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1017/s0016756800032052 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0016756800032052 |
id |
crcambridgeupr:10.1017/s0016756800032052 |
---|---|
record_format |
openpolar |
spelling |
crcambridgeupr:10.1017/s0016756800032052 2024-09-30T14:37:26+00:00 Structure and eruptive mechanisms at Surtsey Volcano, Iceland Moore, James G. 1985 http://dx.doi.org/10.1017/s0016756800032052 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0016756800032052 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Geological Magazine volume 122, issue 6, page 649-661 ISSN 0016-7568 1469-5081 journal-article 1985 crcambridgeupr https://doi.org/10.1017/s0016756800032052 2024-09-04T04:03:24Z Abstract Glassy basalt tuff was the primary material cored in 1979 from a 181 m deep drill hole on the east tuff ring of Surtsey volcano. Despite the fact that the hole extends 122 m below sea level all the core is similar to the exposed tephra composing the two tuff rings of the island. The tuff includes abundant accretionary lapilli and tuff vesicles, indicating that it was all deposited subaerially. During the growth of the tuff rings, repeated hydromagmatic explosion cycles began with a series of intermittent tephra-finger explosions leading up to continuous uprush explosions which lasted for several minutes to several hours. This nozzle-like continuous activity produced eruption columns 100–250 m in diameter and 500–2000 m in height which probably quarried several hundred metres below the ground surface. The continuous-uprush explosion type provides a reasonable mechanism to excavate a diatreme from the top down. During construction of the tuff rings, concentric faults repeatedly downdropped a funnel-like structure (400–800 m in diameter) several hundred metres, thus accounting for the presence of subaerially deposited tephra in the drill core far beneath sea level. Ring dykes later intruded upward along these faults and fed small lava flows. Heat in the surface tephra probably originated primarily from these shallow intrusions. Article in Journal/Newspaper Iceland Surtsey Cambridge University Press Surtsey ENVELOPE(-20.608,-20.608,63.301,63.301) Nozzle ENVELOPE(159.100,159.100,-79.917,-79.917) Geological Magazine 122 6 649 661 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
Abstract Glassy basalt tuff was the primary material cored in 1979 from a 181 m deep drill hole on the east tuff ring of Surtsey volcano. Despite the fact that the hole extends 122 m below sea level all the core is similar to the exposed tephra composing the two tuff rings of the island. The tuff includes abundant accretionary lapilli and tuff vesicles, indicating that it was all deposited subaerially. During the growth of the tuff rings, repeated hydromagmatic explosion cycles began with a series of intermittent tephra-finger explosions leading up to continuous uprush explosions which lasted for several minutes to several hours. This nozzle-like continuous activity produced eruption columns 100–250 m in diameter and 500–2000 m in height which probably quarried several hundred metres below the ground surface. The continuous-uprush explosion type provides a reasonable mechanism to excavate a diatreme from the top down. During construction of the tuff rings, concentric faults repeatedly downdropped a funnel-like structure (400–800 m in diameter) several hundred metres, thus accounting for the presence of subaerially deposited tephra in the drill core far beneath sea level. Ring dykes later intruded upward along these faults and fed small lava flows. Heat in the surface tephra probably originated primarily from these shallow intrusions. |
format |
Article in Journal/Newspaper |
author |
Moore, James G. |
spellingShingle |
Moore, James G. Structure and eruptive mechanisms at Surtsey Volcano, Iceland |
author_facet |
Moore, James G. |
author_sort |
Moore, James G. |
title |
Structure and eruptive mechanisms at Surtsey Volcano, Iceland |
title_short |
Structure and eruptive mechanisms at Surtsey Volcano, Iceland |
title_full |
Structure and eruptive mechanisms at Surtsey Volcano, Iceland |
title_fullStr |
Structure and eruptive mechanisms at Surtsey Volcano, Iceland |
title_full_unstemmed |
Structure and eruptive mechanisms at Surtsey Volcano, Iceland |
title_sort |
structure and eruptive mechanisms at surtsey volcano, iceland |
publisher |
Cambridge University Press (CUP) |
publishDate |
1985 |
url |
http://dx.doi.org/10.1017/s0016756800032052 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0016756800032052 |
long_lat |
ENVELOPE(-20.608,-20.608,63.301,63.301) ENVELOPE(159.100,159.100,-79.917,-79.917) |
geographic |
Surtsey Nozzle |
geographic_facet |
Surtsey Nozzle |
genre |
Iceland Surtsey |
genre_facet |
Iceland Surtsey |
op_source |
Geological Magazine volume 122, issue 6, page 649-661 ISSN 0016-7568 1469-5081 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s0016756800032052 |
container_title |
Geological Magazine |
container_volume |
122 |
container_issue |
6 |
container_start_page |
649 |
op_container_end_page |
661 |
_version_ |
1811640296700641280 |