气候变化领域集成服务门户(CCPortal): Origin and Properties of Hydrothermal Tremor at Lone Star Geyser, Yellowstone National Park, USA

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DOI	10.1029/2020JB019711
	Origin and Properties of Hydrothermal Tremor at Lone Star Geyser, Yellowstone National Park, USA
	Nayak A.; Manga M.; Hurwitz S.; Namiki A.; Dawson P.B.
发表日期	2020
ISSN	21699313
卷号	125 期号:12
英文摘要	Geysers are rare geologic features that intermittently discharge liquid water and steam driven by heating and decompression boiling. The cause of variability in eruptive styles and the associated seismic signals are not well understood. Data collected from five broadband seismometers at Lone Star Geyser, Yellowstone National Park are used to determine the properties, location, and temporal patterns of hydrothermal tremor. The tremor is harmonic at some stages of the eruption cycle and is caused by near-periodic repetition of discrete seismic events. Using the polarization of ground motion, we identify the location of tremor sources throughout several eruption cycles. During preplay episodes (smaller eruptions preceding the more vigorous major eruption), tremor occurs at depths of 7–10 m and is laterally offset from the geyser's cone by ~5 m. At the onset of the main eruption, tremor sources migrate laterally and become shallower. As the eruption progresses, tremor sources migrate along the same path but in the opposite direction, ending where preplay tremor originates. The upward and then downward migration of tremor sources during eruptions are consistent with warming of the conduit followed by evacuation of water during the main eruption. We identify systematic relations among the two types of preplays, discharge, and the main eruption. A point-source moment tensor fit to low-frequency waveforms of an individual tremor event using half-space velocity models indicates average VS ≳ 0.8 km/s, source depths ~4–20 m, and moment tensors with primarily positive isotropic and compensated linear vector dipole moments. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.
英文关键词	Geyser; hydrothermal tremor; moment tensor; tremor polarization; volcanic tremor; Yellowstone National Park
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/187481
作者单位	Department of Earth and Planetary Science, University of California, Berkeley, Berkeley, CA, United States; Now at Earth and Environmental Sciences Area, Lawrence Berkeley National Laboratory, Berkeley, CA, United States; U.S. Geological Survey, Moffett Field, CA, United States; School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan
推荐引用方式 GB/T 7714	Nayak A.,Manga M.,Hurwitz S.,et al. Origin and Properties of Hydrothermal Tremor at Lone Star Geyser, Yellowstone National Park, USA[J],2020,125(12).
APA	Nayak A.,Manga M.,Hurwitz S.,Namiki A.,&Dawson P.B..(2020).Origin and Properties of Hydrothermal Tremor at Lone Star Geyser, Yellowstone National Park, USA.Journal of Geophysical Research: Solid Earth,125(12).
MLA	Nayak A.,et al."Origin and Properties of Hydrothermal Tremor at Lone Star Geyser, Yellowstone National Park, USA".Journal of Geophysical Research: Solid Earth 125.12(2020).