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  • Noble gas isotopes reveal degassing-derived eruptions at Deception Island (Antarctica): implications for the current high levels of volcanic activity
Title: Noble gas isotopes reveal degassing-derived eruptions at Deception Island (Antarctica): implications for the current high levels of volcanic activity
Abstract Deception Island is one of the most active volcanoes in Antarctica with more than twenty explosive eruptions in the past two centuries. Any future volcanic eruption(s) is a serious concern for scientists and tourists, will be detrimental to marine ecosystems and could have an impact to global oceanographic processes. Currently, it is not possible to carry-out low and high frequency volcanic gas monitoring at Deception Island because of the arduous climatic conditions and its remote location. Helium, neon and argon isotopes measured in olivine samples of the main eruptive events (pre-, syn- and post caldera) offer insights into the processes governing its volcanic history. Our results show that: (i) ascending primitive magmas outgassed volatiles with a MORB-like helium isotopic signature ( 3 He/ 4 He ratio); and (ii) variations in the He isotope ratio, as well as intensive degassing evidenced by fractionated 4 He/ 40 Ar * values, occurred before the beginning of the main eruptive episodes. Our results show how the pre-eruptive noble gas signals of volcanic activity is an important step toward a better understanding of the magmatic dynamics and has the potential to improve eruption forecasting.  more » « less
Award ID(s):
2137467
PAR ID:
10384560
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Scientific Reports
Volume:
12
Issue:
1
ISSN:
2045-2322
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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