Browsing by Author "Cronin, Shane J."

Now showing 1 - 8 of 8
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    Community Emergency Management During the 2005 Ambae Eruption, Vanuatu, SW Pacific.
    (Massey University., 2007-01-01) Cronin, Shane J.; Nemeth, Karoly; Procter, John N.; Charley, Douglas T.; Harrison, Morris J; Garaebiti, Esline; Scott, Brad J.; Sherburne, Steve; Bani, Philipson; Lardy, Michel
    No abstract available
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    The day Mount Manaro stirred
    (Massey University., 2007-01-01) Cronin, Shane J.; Nemeth, Karoly; Charley, Douglas T.; Thulstrup, Hans D.
    No abstract available
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    A large-scale, near-sea level, silicic caldera-forming eruption in Efate? An alternative model for the 1 Ma Efate Pumice Formation, Vanuatu, SW-Pacific
    (Massey University., 2007-01-01) Stewart, Robert B.; Nemeth, Karoly; Cronin, Shane J.; Charley, Douglas T.
    No abstract available
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    Lava lakes and shallow level magmatic feeding systems of mafic volcanoes of an ocean island: Ambrym, Vanuatu (New Hebrides), South Pacific
    (Massey University., 2006-01-01) Nemeth, Karoly; Cronin, Shane J.
    Ambrym is an active volcanic island with 2 major vent complexes; Marum and Benbow. These vent complexes are continuously active over at least the past two thousands of years. These active vents either produce constant degassing during quite periods or sub-Plinian to Vulcanian explosive eruptions commonly influenced by magma-water interaction triggered phreatomagmatic explosive phases. The active vents of Ambrym perfectly expos inner walls of the crater/conduit transition zone, allowing to study in cross sectional view of the interbedded coherent magmatic bodies with pyroclastic successions. In the inner crater/conduit wall of the Marum volcano, that consists of at least 3 major vents, as well as a vent that is located on its flank (Niri Taten) exposes solidified complex lava lake cross-sections, lava spatter cone feeding lava pods, shallow intrusions as well as large sills that connected through a complex network of pathways to the surface and/or into the pyroclastic edifice of the volcano. This suggests that shallow level infiltration of melt into a mafic volcano plays an important role in the edifice growth.
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    Magmaticand phreatomagmatic tephras in fine ash successions of an arc volcanic complex, the Mangatawai Tephra Formation, Tongariro Volcanic Centre, New Zealand
    (Massey University., 2007-01-01) Moebis, Anja; Cronin, Shane J.; Nemeth, Karoly
    No abstract available
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    Peperites and soft sediment deformation textures of a shallow subaqueous Miocene rhyolitic cryptodome and dyke complex, Pálháza, Hungary
    (Massey University., 2006-01-01) Nemeth, Karoly; Pecskay, Zoltan; Martin, Ulrike; Gmeling, Katalin; Molnar, Ferenc; Cronin, Shane J.
    Miocene rhyolitic shallow intrusions, cryptodomes and domes emplaced into soft, wet sediment in shallow subaqueous environment form a large intrusive complex in the NE side of the Tokaj Mts. at Pálháza in NE-Hungary. The intrusive complex show interaction textures with the host sediment where blocky peperites formed in a dm-scale, however, irregular contacts closely resembling globular mega-peperites are prominent in the tens of metres scale. The more than 200 m thick succession of intrusive complex interpreted to be a generally steadily growing shallow dyke, cryptodome, and dome complex in a shallow subaqueous environment, similar to those reported from Ponza, Italy.
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    Samoa technical report - Review of volcanic hazard maps for Savai'i and Upolu
    (South Pacific Applied Geoscience Commission, 2006-07) Cronin, Shane J.; Bonte-Grapentin, Michael; Nemeth, Karoly
    Both main islands of Samoa, Savai'i and Upolu need to be considered as potentially volcanically active. The most recent eruptions in historic times happened on Savai'i in 1905-1911, 1902 and 1760 (estimated). Though detailed volcanic studies and dating of volcanic events are very limited there is evidence for repeated volcanic activity on both islands since the time of human occupation of the islands marked by prominent and fresh appearance of tuff cones as Tafua (= fire mountain) Savai'i, the island of Apolima, Tafua Upolu and offshore Cape Tapaga. This report examines the volcanic risks for both islands and defines for disaster management considerations potential eruption scenarios based on eyewitness accounts of previous eruptions, geological field evidence, remote sensing information and experiences from similar volcanoes. A detailed timeline of events, potential impacts and required emergency response activities are listed for the five potential eruption types (1) long-term lava field (2) short-term spatter-cone (3) explosive phreatomagmatic (4) explosive scoria-cone and (5) submarine flank collapse. Given the nature of volcanism in Samoa with hundreds of individual "one-off" volcanoes scattered along zones of structural weakness within the Savai'i - Upolu Platform - predicting the exact location of future eruption centres is impossible. At the current stage of knowledge a presentation of a volcanic hazard map is inadequate and would require additional baseline studies to statistically define recurrence intervals and areas of higher volcanic activity. Taking these limitations into account, maps showing the relative potential for new eruption vents on Upolu and Savai'i are derived from geomorphologic features. To improve our understanding and management of the volcanic risks of Samoa, suggestions for achievable future work are listed and prioritised. These recommendations include geological/volcanological baseline studies (e.g. dating/detailed analyses of past events, rock chemistry, volcano structure); installation of early warning and monitoring network (e.g. permanent GPS, seismometers); and disaster preparedness and volcanic crisis response planning.
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