東華大學圖書館 |

語系: 繁體中文

說明(常見問題)

回圖書館首頁

手機版館藏查詢

登入

回首頁

切換: 標籤 | MARC模式 | ISBD

Weak-intensity, basaltic, explosive ...

Parcheta, Carolyn.

FindBook

Google Book

Amazon

博客來

Weak-intensity, basaltic, explosive volcanism: Dynamics of Hawaiian fountains.

紀錄類型:	書目-語言資料,印刷品 : Monograph/item
正題名/作者:	Weak-intensity, basaltic, explosive volcanism: Dynamics of Hawaiian fountains./
作者:	Parcheta, Carolyn.
面頁冊數:	202 p.
附註:	Source: Dissertation Abstracts International, Volume: 74-11(E), Section: B.
Contained By:	Dissertation Abstracts International74-11B(E).
標題:	Geology. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3572484
ISBN:	9781303313936

Weak-intensity, basaltic, explosive volcanism: Dynamics of Hawaiian fountains.
Parcheta, Carolyn.

Weak-intensity, basaltic, explosive volcanism: Dynamics of Hawaiian fountains. - 202 p.

Source: Dissertation Abstracts International, Volume: 74-11(E), Section: B.

Thesis (Ph.D.)--University of Hawai'i at Manoa, 2013.

Hawaiian fountains, typically occurring on basaltic volcanoes, are sustained, weakly-explosive jets of gas and juvenile ejecta. A broad range of Hawaiian fountaining styles occurred during twelve episodes of the Mauna Ulu eruption on Kilauea between May and December 1969. The western episode 1 fissure system is currently well exposed, providing an exclusive opportunity to study processes of low-intensity fissure fountains. Episode 1 fountains occurred along a 5 km long fissure system that exploited the eastern-most kilometer of the Ko'ai fault system. A low, near-continuous, spatter rampart is present on the northern upwind and upslope side of the fissure. Most pyroclastic products, however, fell downwind to the south and little was preserved because of two processes: 1) incorporation of proximal spatter in rheomorphic lava flows 10--20 meters from the vents, and 2) downslope transport of cooler spatter falling on top of these flows >20 meters from vent. There is a clear 'lava-shed' delineation between lava that drained back into the fissure and lava that continued flowing into the flowfield. Vents range in surface geometry from linear--circular, with superimposed irregularity and sinuosity, and range from straight-sided--flaring cross-sectional geometries. Irregularity results from joints in the pre-existing wall rock. Sinuosity results from the local stress field. Geometry of non-flared vents could indicate the true geometry of the dike. Flared vents likely formed through mechanical erosion and thermo-mechanical abrasion. Vent positions along the fissure likely resulted from flow focusing. Uniquely, these vents drained and remain unobstructed (some >100 m depth), despite subsequent nearby eruptive activity. Three vents were imaged .16 m in depth at <4 cm resolution with tripodmounted LiDAR. Textural analyses of pyroclasts from eruptive episodes 2.12 show three distinct degassing and outgassing paths: 1) rapid degassing and quenching with minimal outgassing, 2) prolonged degassing and outgassing, and 3) rapid degassing and quenching on pyroclasts' rims with prolonged internal bubble coalesce. Contrasting patterns of shallow degassing and outgassing were the dominant control driving Hawaiian fountain behavior and variability, and are probably the dominant control for many other Hawaiian-style eruptions.

ISBN: 9781303313936Subjects--Topical Terms:

516570
Geology.

Weak-intensity, basaltic, explosive volcanism: Dynamics of Hawaiian fountains.
LDR:03231nam a2200277 4500 001 1968893
005 20141231071630.5
008 150210s2013 ||||||||||||||||| ||eng d
020 $a 9781303313936
035 $a (MiAaPQ)AAI3572484
035 $a AAI3572484
040 $a MiAaPQ $c MiAaPQ
100 1 $a Parcheta, Carolyn. $3 2106120
245 1 0 $a Weak-intensity, basaltic, explosive volcanism: Dynamics of Hawaiian fountains.
300 $a 202 p.
500 $a Source: Dissertation Abstracts International, Volume: 74-11(E), Section: B.
500 $a Adviser: Bruce Houghton.
502 $a Thesis (Ph.D.)--University of Hawai'i at Manoa, 2013.
520 $a Hawaiian fountains, typically occurring on basaltic volcanoes, are sustained, weakly-explosive jets of gas and juvenile ejecta. A broad range of Hawaiian fountaining styles occurred during twelve episodes of the Mauna Ulu eruption on Kilauea between May and December 1969. The western episode 1 fissure system is currently well exposed, providing an exclusive opportunity to study processes of low-intensity fissure fountains. Episode 1 fountains occurred along a 5 km long fissure system that exploited the eastern-most kilometer of the Ko'ai fault system. A low, near-continuous, spatter rampart is present on the northern upwind and upslope side of the fissure. Most pyroclastic products, however, fell downwind to the south and little was preserved because of two processes: 1) incorporation of proximal spatter in rheomorphic lava flows 10--20 meters from the vents, and 2) downslope transport of cooler spatter falling on top of these flows >20 meters from vent. There is a clear 'lava-shed' delineation between lava that drained back into the fissure and lava that continued flowing into the flowfield. Vents range in surface geometry from linear--circular, with superimposed irregularity and sinuosity, and range from straight-sided--flaring cross-sectional geometries. Irregularity results from joints in the pre-existing wall rock. Sinuosity results from the local stress field. Geometry of non-flared vents could indicate the true geometry of the dike. Flared vents likely formed through mechanical erosion and thermo-mechanical abrasion. Vent positions along the fissure likely resulted from flow focusing. Uniquely, these vents drained and remain unobstructed (some >100 m depth), despite subsequent nearby eruptive activity. Three vents were imaged .16 m in depth at <4 cm resolution with tripodmounted LiDAR. Textural analyses of pyroclasts from eruptive episodes 2.12 show three distinct degassing and outgassing paths: 1) rapid degassing and quenching with minimal outgassing, 2) prolonged degassing and outgassing, and 3) rapid degassing and quenching on pyroclasts' rims with prolonged internal bubble coalesce. Contrasting patterns of shallow degassing and outgassing were the dominant control driving Hawaiian fountain behavior and variability, and are probably the dominant control for many other Hawaiian-style eruptions.
590 $a School code: 0085.
650 4 $a Geology. $3 516570
650 4 $a Geophysics. $3 535228
690 $a 0372
690 $a 0373
710 2 $a University of Hawai'i at Manoa. $b Geology and Geophysics. $3 2106121
773 0 $t Dissertation Abstracts International $g 74-11B(E).
790 $a 0085
791 $a Ph.D.
792 $a 2013
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3572484