Unraveling the evolution, dynamics and time-scales of magmatic processes below the volcano, West-Java, Indonesia
Gede is the closest active stratovolcano to the capital of Indonesia, thus it is a potential hazard to millions of people around the volcano and in Jakarta. It is currently being monitored by various geophysical methods in a collaborative project between CVGHM and EOS. However, interpretation of new...
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Format: | Thesis |
Language: | English |
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2016
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Online Access: | http://hdl.handle.net/10356/68520 |
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author | Krimer, Daniel |
author2 | Fidel Costa Rodriguez |
author_facet | Fidel Costa Rodriguez Krimer, Daniel |
author_sort | Krimer, Daniel |
collection | NTU |
description | Gede is the closest active stratovolcano to the capital of Indonesia, thus it is a potential hazard to millions of people around the volcano and in Jakarta. It is currently being monitored by various geophysical methods in a collaborative project between CVGHM and EOS. However, interpretation of new unrest is fraught with uncertainty unless its geological and petrological history is well understood. I present here a detailed petrochemical study to untangle Gede’s past history since about the last 45 kyr to present that sheds light on its magmatic evolution and reservoir dynamics, and the time-scales of these processes. A key finding is that Gede’s evolutionary path changed in the Holocene: the main magma dynamics has shifted from a deep mafic reservoir (about 24 km below its summit) to a shallow one (at about 4 km) made of silica-rich melts. Mingling and mixing of volatile-rich basaltic and crystal-rich rhyolitic magmas is one of the most important processes that lead to the main erupted compositions (andesites) and which also may lead to eruption. Three-dimensional numerical simulation of diffusion of chemically zoned minerals reveals that these shallow reservoir processes start probably only a month before eruption. These results should guide interpretations of monitoring signals and improve hazard mitigation efforts in a future unrest event. |
first_indexed | 2024-10-01T07:03:25Z |
format | Thesis |
id | ntu-10356/68520 |
institution | Nanyang Technological University |
language | English |
last_indexed | 2024-10-01T07:03:25Z |
publishDate | 2016 |
record_format | dspace |
spelling | ntu-10356/685202023-02-28T16:52:54Z Unraveling the evolution, dynamics and time-scales of magmatic processes below the volcano, West-Java, Indonesia Krimer, Daniel Fidel Costa Rodriguez Asian School of the Environment DRNTU::Science::Geology::Volcanoes and earthquakes Gede is the closest active stratovolcano to the capital of Indonesia, thus it is a potential hazard to millions of people around the volcano and in Jakarta. It is currently being monitored by various geophysical methods in a collaborative project between CVGHM and EOS. However, interpretation of new unrest is fraught with uncertainty unless its geological and petrological history is well understood. I present here a detailed petrochemical study to untangle Gede’s past history since about the last 45 kyr to present that sheds light on its magmatic evolution and reservoir dynamics, and the time-scales of these processes. A key finding is that Gede’s evolutionary path changed in the Holocene: the main magma dynamics has shifted from a deep mafic reservoir (about 24 km below its summit) to a shallow one (at about 4 km) made of silica-rich melts. Mingling and mixing of volatile-rich basaltic and crystal-rich rhyolitic magmas is one of the most important processes that lead to the main erupted compositions (andesites) and which also may lead to eruption. Three-dimensional numerical simulation of diffusion of chemically zoned minerals reveals that these shallow reservoir processes start probably only a month before eruption. These results should guide interpretations of monitoring signals and improve hazard mitigation efforts in a future unrest event. Doctor of Philosophy (ASE) 2016-05-26T07:21:00Z 2016-05-26T07:21:00Z 2016 Thesis Krimer, D. (2016). Unraveling the evolution, dynamics and time-scales of magmatic processes below the volcano, West-Java, Indonesia. Doctoral thesis, Nanyang Technological University, Singapore. http://hdl.handle.net/10356/68520 10.32657/10356/68520 en 262 p. application/pdf |
spellingShingle | DRNTU::Science::Geology::Volcanoes and earthquakes Krimer, Daniel Unraveling the evolution, dynamics and time-scales of magmatic processes below the volcano, West-Java, Indonesia |
title | Unraveling the evolution, dynamics and time-scales of magmatic processes below the volcano, West-Java, Indonesia |
title_full | Unraveling the evolution, dynamics and time-scales of magmatic processes below the volcano, West-Java, Indonesia |
title_fullStr | Unraveling the evolution, dynamics and time-scales of magmatic processes below the volcano, West-Java, Indonesia |
title_full_unstemmed | Unraveling the evolution, dynamics and time-scales of magmatic processes below the volcano, West-Java, Indonesia |
title_short | Unraveling the evolution, dynamics and time-scales of magmatic processes below the volcano, West-Java, Indonesia |
title_sort | unraveling the evolution dynamics and time scales of magmatic processes below the volcano west java indonesia |
topic | DRNTU::Science::Geology::Volcanoes and earthquakes |
url | http://hdl.handle.net/10356/68520 |
work_keys_str_mv | AT krimerdaniel unravelingtheevolutiondynamicsandtimescalesofmagmaticprocessesbelowthevolcanowestjavaindonesia |