Details

Autor(en) / Beteiligte

• Kedar, Sharon
• Panning, Mark P.
• Smrekar, Suzanne E.
• Stähler, Simon C.
• King, Scott D.
• Golombek, Matthew P.
• Manga, Michael
• Julian, Bruce R.
• Shiro, Brian
• Perrin, Clement
• Power, John A.
• Michaut, Chloe
• Ceylan, Savas
• Giardini, Domenico
• Lognonné, Philippe H.
• Banerdt, William B.

Titel

Analyzing Low Frequency Seismic Events at Cerberus Fossae as Long Period Volcanic Quakes

Ist Teil von

• Journal of geophysical research. Planets, 2021-04, Vol.126 (4), p.n/a

Ort / Verlag

Washington: Blackwell Publishing Ltd

Erscheinungsjahr

2021

Link zum Volltext

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• The InSight Mission began acquiring the first seismic data on Mars in early 2019 and has detected hundreds of events. The largest events recorded to date originate at Cerberus Fossae, a young volcanic region characterized by high volume, low viscosity lava flows. A handful of Low Frequency (LF) quakes that share key attributes of Long Period quakes recorded on Earth's volcanoes are also traced to Cerberus Fossae. This study explores whether a traditional volcanic source model that simulates the generation of tremor as pressurized fluid makes its way through a channel at depth, can explain these atypical LF events. We consider a wide range of physical parameters including fluid viscosity, the ratio of driving pressure to lithostatic pressure, aspect ratio of the channel, and the equilibrium channel opening. We find that the model can produce the observed seismic signature, with a combination of low‐viscosity magma and high volume flux of ∼104 − 105 m3/s that are within an order‐of‐magnitude agreement with Cerberus Fossae lava flow properties deduced from analysis of lava flow dimensions. It is impossible, however, at this stage to conclude whether or not this is a likely explanation for Mars, as the model results in fluxes that are extreme for Earth yet are just within bounds of what has been inferred for Cerberus Fossae. We therefore conclude that we cannot rule out active magma flow as the mechanism responsible for the atypical LF events that likely originate from Cerberus Fossae. Plain Language Summary A number of Marsquakes are located at a region of Mars that hosted geologically recent volcanic eruptions. A subset of these events resemble seismic events recorded at volcanoes on Earth. We set out to study whether these events can be explained by fluid flow at depth, using a model of fluid flow through a channel. We find that low viscosities and high flow rates that are within an order‐of‐magnitude agreement with flow properties deduced from modeling of Cerberus Fossae lava flows are required to match the observed events in question. It is impossible at this stage of the InSight mission, however, to conclude whether or not this is a likely explanation for Mars. Key Points Low Frequency (LF) events that share attributes of volcanic quakes are traced to a young volcanic region on Mars LF events are modeled as deep volcanic quakes caused by pressure‐driven flow across a channel at Cerberus Fossae LF attributes are matched by fluids less viscous and of higher fluxes than terrestrial flood basalts