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Title: Spatiotemporal gravity changes at the Santorini Volcanic complex and their interpretation
Understanding the complex dynamics of volcanic systems demands a multidimensional approach that combines geophysics, geology, and geodetics. In this study, we examine observed spatiotemporal gravity changes within the Santorini volcanic complex from 1975 to 2014. The historical data indicates that gravity has been increasing continuously since at least 1966 until our latest measurements in 2014, albeit with a decreasing rate of increase over time. Utilizing gravity inversion of various gravity datasets and evidence from other studies, we explore different scenarios to shed light on the underlying processes. Our preferred interpretation involves both a magmatic episode and continuous evolution of the shallow structure. We find that the 2011-12 unrest period resulted from the intrusion of ~3.3x1011 kg of basaltic magma at 3 km depth near the previously identified Mogi source. We attribute the continuous gravity increase beneath Nea Kameni to a density increases at about 1350 m depth. We infer these are a result of hydrothermal fluctuations, degassing, and/or vesicle collapse within the stored magma. Units: 1mGal = 10-5 m/s2 (SI)  more » « less
Award ID(s):
2023338
PAR ID:
10567271
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Quaternary Science Advances
Date Published:
Journal Name:
Quaternary Science Advances
Volume:
13
Issue:
C
ISSN:
2666-0334
Page Range / eLocation ID:
100140
Subject(s) / Keyword(s):
Santorini Spatiotemporal gravity changes Magma source Volcano Greece Caldera
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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