气候变化领域集成服务门户(CCPortal): Detectability of Melt-Rich Lenses in Magmatic Reservoirs From Teleseismic Waveform Modeling

CCPortal

DOI	10.1029/2020JB020264
	Detectability of Melt-Rich Lenses in Magmatic Reservoirs From Teleseismic Waveform Modeling
	Rasht-Behesht M.; Huber C.; Mancinelli N.J.
发表日期	2020
ISSN	21699313
卷号	125 期号:9
英文摘要	Seismic imaging is the most commonly used technique to constrain the size, geometry, and current state of active magma reservoirs in the Earth's crust. However, unequivocal detection of eruptible magma bodies (>0.5 melt fraction) have not been reported yet. In this study, using teleseismic waveform modeling applied to synthetic data, we investigate the limitations of seismic inversions on resolving idealized melt-rich layers with thicknesses smaller than the characteristic wavelength of the teleseismic waves. We show that inverting for melt-rich layers with thicknesses of about 0.2 km, consistent with the average thickness of erupted layers associated with voluminous caldera eruptions, yields significant underestimation of the inferred melt fractions and overestimation of the thickness of that layer. We further extend our synthetic tests to study the effect of noise, variable thickness of the input melt-rich layer, and different time windows from the seismograms on the quality of inverted parameters (thickness and melt fraction of the melt-rich layer). We find that (1) thicker melt-rich layers can be better resolved, (2) longer time windows (~4–6 s) from seismograms reduce the trade-off between melt fraction and layer thickness observed in the inversion results, and (3) noise emphasizes the melt fraction-thickness trade-off and leads to a bias toward thicker lower melt fraction layers retrieved from the inversions. Our synthetic study therefore supports that the lack of detection of melt-dominated horizons from seismic inversions does not preclude their existence and can be caused by a current limit in our ability to detect them. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	inversion; magma reservoir; P-to-S converted phases; synthetics; teleseismic waves
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187621
作者单位	Department of Earth Environmental and Planetary Sciences, Brown University, Providence, RI, United States
推荐引用方式 GB/T 7714	Rasht-Behesht M.,Huber C.,Mancinelli N.J.. Detectability of Melt-Rich Lenses in Magmatic Reservoirs From Teleseismic Waveform Modeling[J],2020,125(9).
APA	Rasht-Behesht M.,Huber C.,&Mancinelli N.J..(2020).Detectability of Melt-Rich Lenses in Magmatic Reservoirs From Teleseismic Waveform Modeling.Journal of Geophysical Research: Solid Earth,125(9).
MLA	Rasht-Behesht M.,et al."Detectability of Melt-Rich Lenses in Magmatic Reservoirs From Teleseismic Waveform Modeling".Journal of Geophysical Research: Solid Earth 125.9(2020).