Christina A. Neal (Former Employee)
Science and Products
Filter Total Items: 96
Water-magma interaction and plume processes in the 2008 Okmok eruption, Alaska Water-magma interaction and plume processes in the 2008 Okmok eruption, Alaska
Eruptions of similar explosivity can have divergent effects on the surroundings due to differences in the behavior of the tephra in the eruption column and atmosphere. Okmok volcano, located on Umnak Island in the eastern Aleutian Islands, erupted explosively between 12 July and 19 August 2008. The basaltic andesitic eruption ejected ∼0.24 km3dense rock equivalent (DRE) of tephra...
Authors
Joel A. Unema, Michael H. Ort, Jessica D Larsen, Christina A. Neal, Janet R. Schaefer
Aniakchak National Monument and Preserve: Geologic resources inventory report Aniakchak National Monument and Preserve: Geologic resources inventory report
This GRI report is a companion document to previously completed GRI digital geologic map data. It was written for resource managers to support science-informed decision making. It may also be useful for interpretation. The report was prepared using available geologic information, and the NPS Geologic Resources Division conducted no new fieldwork in association with its preparation...
Authors
Chad P. Hults, Christina A. Neal
2013 volcanic activity in Alaska: summary of events and response of the Alaska Volcano Observatory 2013 volcanic activity in Alaska: summary of events and response of the Alaska Volcano Observatory
The Alaska Volcano Observatory (AVO) responded to eruptions, volcanic unrest or suspected unrest, and seismic events at 18 volcanic centers in Alaska during 2013. Beginning with the 2013 AVO Summary of Events, the annual description of the AVO seismograph network and activity, once a stand-alone publication, is now part of this report. Because of this change, the annual summary now...
Authors
James P. Dixon, Cheryl Cameron, Robert G. McGimsey, Christina A. Neal, Chris Waythomas
The 2008 phreatomagmatic eruption of Okmok volcano, Aleutian Islands, Alaska: Chronology, deposits, and landform changes The 2008 phreatomagmatic eruption of Okmok volcano, Aleutian Islands, Alaska: Chronology, deposits, and landform changes
Okmok volcano, Aleutian Islands, Alaska, explosively erupted over a five-week period between July 12 and August 23, 2008. The eruption was predominantly phreatomagmatic, producing fine-grained tephra that covered most of northeastern Umnak Island. The eruption had a maximum Volcanic Explosivity Index (VEI) of 4, with eruption column heights up to 16 km during the opening phase. Several...
Authors
Jessica Larsen, Christina A. Neal, Janet R. Schaefer, Max Kaufman, Zhong Lu
Postglacial eruptive history, geochemistry, and recent seismicity of Aniakchak volcano, Alaska Peninsula Postglacial eruptive history, geochemistry, and recent seismicity of Aniakchak volcano, Alaska Peninsula
Aniakchak is a Pleistocene to Holocene composite volcano of the Alaska–Aleutian arc that suffered at least one caldera-forming eruption in postglacial time and last erupted in 1931. The oldest recognized postglacial eruption, Aniakchak I, produced andesite ignimbrite ca. 9,500–7,500 14C yr B.P. Subsequently, a vent northeast of the summit issued dacite–rhyodacite magma ca. 7,000 14C yr B...
Authors
Charles R. Bacon, Christina A. Neal, Thomas P. Miller, Robert G. McGimsey, Christopher J. Nye
2012 volcanic activity in Alaska: Summary of events and response of the Alaska Volcano Observatory 2012 volcanic activity in Alaska: Summary of events and response of the Alaska Volcano Observatory
The Alaska Volcano Observatory (AVO) responded to eruptions, possible eruptions, volcanic unrest, or suspected unrest at 11 volcanic centers in Alaska during 2012. Of the two verified eruptions, one (Cleveland) was clearly magmatic and the other (Kanaga) was most likely a single phreatic explosion. Two other volcanoes had notable seismic swarms that probably were caused by magmatic...
Authors
Julie A. Herrick, Christina A. Neal, Cheryl E. Cameron, James P. Dixon, Robert G. McGimsey
Filter Total Items: 61
Science and Products
Filter Total Items: 96
Water-magma interaction and plume processes in the 2008 Okmok eruption, Alaska Water-magma interaction and plume processes in the 2008 Okmok eruption, Alaska
Eruptions of similar explosivity can have divergent effects on the surroundings due to differences in the behavior of the tephra in the eruption column and atmosphere. Okmok volcano, located on Umnak Island in the eastern Aleutian Islands, erupted explosively between 12 July and 19 August 2008. The basaltic andesitic eruption ejected ∼0.24 km3dense rock equivalent (DRE) of tephra...
Authors
Joel A. Unema, Michael H. Ort, Jessica D Larsen, Christina A. Neal, Janet R. Schaefer
Aniakchak National Monument and Preserve: Geologic resources inventory report Aniakchak National Monument and Preserve: Geologic resources inventory report
This GRI report is a companion document to previously completed GRI digital geologic map data. It was written for resource managers to support science-informed decision making. It may also be useful for interpretation. The report was prepared using available geologic information, and the NPS Geologic Resources Division conducted no new fieldwork in association with its preparation...
Authors
Chad P. Hults, Christina A. Neal
2013 volcanic activity in Alaska: summary of events and response of the Alaska Volcano Observatory 2013 volcanic activity in Alaska: summary of events and response of the Alaska Volcano Observatory
The Alaska Volcano Observatory (AVO) responded to eruptions, volcanic unrest or suspected unrest, and seismic events at 18 volcanic centers in Alaska during 2013. Beginning with the 2013 AVO Summary of Events, the annual description of the AVO seismograph network and activity, once a stand-alone publication, is now part of this report. Because of this change, the annual summary now...
Authors
James P. Dixon, Cheryl Cameron, Robert G. McGimsey, Christina A. Neal, Chris Waythomas
The 2008 phreatomagmatic eruption of Okmok volcano, Aleutian Islands, Alaska: Chronology, deposits, and landform changes The 2008 phreatomagmatic eruption of Okmok volcano, Aleutian Islands, Alaska: Chronology, deposits, and landform changes
Okmok volcano, Aleutian Islands, Alaska, explosively erupted over a five-week period between July 12 and August 23, 2008. The eruption was predominantly phreatomagmatic, producing fine-grained tephra that covered most of northeastern Umnak Island. The eruption had a maximum Volcanic Explosivity Index (VEI) of 4, with eruption column heights up to 16 km during the opening phase. Several...
Authors
Jessica Larsen, Christina A. Neal, Janet R. Schaefer, Max Kaufman, Zhong Lu
Postglacial eruptive history, geochemistry, and recent seismicity of Aniakchak volcano, Alaska Peninsula Postglacial eruptive history, geochemistry, and recent seismicity of Aniakchak volcano, Alaska Peninsula
Aniakchak is a Pleistocene to Holocene composite volcano of the Alaska–Aleutian arc that suffered at least one caldera-forming eruption in postglacial time and last erupted in 1931. The oldest recognized postglacial eruption, Aniakchak I, produced andesite ignimbrite ca. 9,500–7,500 14C yr B.P. Subsequently, a vent northeast of the summit issued dacite–rhyodacite magma ca. 7,000 14C yr B...
Authors
Charles R. Bacon, Christina A. Neal, Thomas P. Miller, Robert G. McGimsey, Christopher J. Nye
2012 volcanic activity in Alaska: Summary of events and response of the Alaska Volcano Observatory 2012 volcanic activity in Alaska: Summary of events and response of the Alaska Volcano Observatory
The Alaska Volcano Observatory (AVO) responded to eruptions, possible eruptions, volcanic unrest, or suspected unrest at 11 volcanic centers in Alaska during 2012. Of the two verified eruptions, one (Cleveland) was clearly magmatic and the other (Kanaga) was most likely a single phreatic explosion. Two other volcanoes had notable seismic swarms that probably were caused by magmatic...
Authors
Julie A. Herrick, Christina A. Neal, Cheryl E. Cameron, James P. Dixon, Robert G. McGimsey
Filter Total Items: 61
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government