A detection of Milankovitch Periodocity in records of global arc volcanism
Jegen, Marion D., Kutterolf, Steffen, Mitrovica, J. X., Kwasnitschka, Tom, Freundt, Armin and Huybers, P. (2010) A detection of Milankovitch Periodocity in records of global arc volcanism [Poster] In: AGU Fall Meeting 2010, 13.12.-17.12.2010, San Francisco, California, USA .Full text not available from this repository. (Contact)
The intervals between volcanic activity varies on a wide range of spatial and temporal scales, from less than a year in single volcanic systems to timescales of 10^6 years and longer in global volcanism. The causes of these timescales are poorly understood although the long-term global variations are likely linked to plate-tectonic processes. Here we present evidence for temporal changes in eruption frequencies at an intermediate timescale (10 000 years). In particular we use the Pleistocene to Recent records of widespread tephras of sub-Plinian to Plinian, and occasionally co-ignimbrite origin, along the Pacific Ring of Fire, which accounts for about half of the global length of 44,000 km of active subduction. Eruptions at arc volcanoes tend to be highly explosive and the well-preserved tephra records from the ocean floor can be assumed to be representative of how eruption frequencies varied with time. We show that volcanic activity along the Pacific Ring of Fire evolved through alternating intervals of high and low activity; although there are regional differences, these variations in activity have a statistically significant periodicity of approximately 41 ka that matches the temporal variation in the Earth's obliquity. This suggests that the timescale of volcanic activity is controlled by effects of global climate changes which result in redistribution of water masses between oceans and polar ice caps. While our statistical correlations suggest that the timescale of volcanic activity is controlled by effects of global climate changes, the physical nature of these effects is presently investigated.
|Document Type:||Conference or Workshop Item (Poster)|
|Keywords:||Volcanology; Global change, Sea level change; Glacial; Tectonophysics, Planetary volcanism; Volcano/climate interactions; Paleoceanography and Paleoclimatology|
|Research affiliation:||OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-MUHS Magmatic and Hydrothermal Systems
OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-GDY Geodynamics
|Date Deposited:||19 Jan 2011 15:18|
|Last Modified:||23 Feb 2012 06:07|
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