Analytical Prediction of Seismicity Rate Due to Tides and Other Oscillating Stresses

Heimisson, Elías Rafn; Avouac, Jean Philippe

doi:10.1029/2020gl090827

Cited by 20 publications

(24 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…InSight offers other opportunities to search for confined aquifers. If fluid pressure in a cryosphere or otherwise confined aquifer is high, the state of stress may be close to that needed to initiate slip on faults, and tidal stresses may trigger marsquakes (Heimisson & Avouac, 2020; Manga et al., 2019). Unfortunately, the large diurnal variations in noise, and hence the ability to detect marsquakes (Giardini et al., 2020), makes it somewhere between very difficult and impossible to identify tidal modulation of seismicity (Knapmeyer et al., 2021).…”

Section: Discussionmentioning

confidence: 99%

No Cryosphere‐Confined Aquifer Below InSight on Mars

Manga

Wright

2021

Geophysical Research Letters

View full text Add to dashboard Cite

Large volumes of water are hypothesized to have carved and passed through the Martian outflow channels (e.g., Baker, 2001). Because these channels originate from discrete sources, a groundwater origin is typically invoked (e.g., Head et al., 2003). Given the large discharges needed to create the observed landforms, in some cases a couple orders of magnitude greater than the largest catastrophic floods on Earth (Baker, 1982), large and permeable aquifers would be needed (e.g., Carr, 1979;Manga, 2004). While most of the outflow channels are Hesperian (e.g., Tanaka, 1997), their formation continued through the Amazonian (e.g., Rodriguez et al., 2015). Some of the youngest channels originated from fissures in Athabasca Valles, Eastern Elysium Planitia within the past 10s of millions of years (Burr et al., 2002;Voigt & Hamilton, 2018). The subsurface of Mars thus appears to have hosted and episodically released large volumes of water over most of Martian history. Hence, detecting the presence and quantifying the volume of subsurface water and ice would help constrain the water budget and cycle from the Noachian to present (e.g., Clifford and Parker, 2001), the amount of water lost to space (e.g., Jakosky, 2021), the fate of possible oceans (e.g., Citron et al., 2018), and the amount of water sequestered in minerals (e.g., Scheller et al., 2021).To discharge water at the surface, aquifers must have sufficient pressure for water to reach the surface. One way to achieve hydraulic heads greater than hydrostatic and hence enable surface discharge is to confine aquifers beneath an overlying ice-saturated crust or cryosphere (e.g., Andrews-Hanna and Phillips, 2007;Carr, 1996;Harrison & Grimm, 2004). As Mars cools and this cryosphere thickens, hydraulic heads will increase and may also create the pressure needed to fracture the crust (Wang et al., 2006). The MARSIS radar system has identified reflections interpreted as lakes confined under Mars' southern ice cap (Lauro et al., 2021;Orosei et al., 2018), though this interpretation is contested (Ojha et al., 2021) and would require recent magmatism (Sori & Bramson, 2019). Aquifers in the crust, if they exist, would be at depths of several kilometers (Clifford et al., 2010), deeper than the MARSIS and SHARAD radar systems can penetrate in volcanic terrain (e.g., Abotalib & Heggy, 2019). MARSIS has not identified a deep reflector indicative of an aquifer below the outflow channels in Athabasca Valles, for example (Clifford et al., 2010). Other geophysical data, such as seismic shear wave velocity, Vs, may be useful because Vs is sensitive to physical properties of the subsurface and probes greater depths.Our objective is to interpret Vs measured by the InSight mission in Elysium Planitia. We use rock physics models to compute effective medium properties and to help distinguish between porous basalt filled with gas, liquid water, ice, or mineral cement. We focus on two observations. First, Vs within Mars' upper

show abstract

Section: Discussionmentioning

confidence: 99%

No Cryosphere‐Confined Aquifer Below InSight on Mars

Manga

Wright

2021

Geophysical Research Letters

View full text Add to dashboard Cite

show abstract

“…InSight offers other opportunities to search for confined aquifers. If fluid pressure in a cryosphere or otherwise confined aquifer is high, the state of stress may be close to that needed to initiate slip on faults, and tidal stresses may trigger marsquakes (Manga et al, 2019;Heimisson and Avouac, 2020). Unfortunately, the large diurnal variations in noise, and hence the ability to detect marsquakes (Giardini et al, 2020), makes it somewhere between very difficult and impossible to identify any tidal modulation of seismicity.…”

Section: Discussionmentioning

confidence: 99%

No cryosphere-confined aquifer below InSight on Mars

Manga

Wright²

2021

Preprint

View full text Add to dashboard Cite

The seismometer deployed by the InSight lander measured the seismic velocity of the Martian crust. We use a rock physics model to interpret those velocities and constrain hydrogeological properties. The seismic velocity of the upper ~10 km is too low to be ice-saturated. Hence there is no cryosphere that confines deeper aquifers. An increase in seismic velocity at depths of ~10 km could be explained by a few volume percent of mineral cement (1-5%) in the pores and may document the past or present depth of aquifers. Plain Language Summary Large amounts of water may be stored in the Martian crust and episodically released to flood the surface. Where this water exists, and even why, is uncertain. The seismometer on the InSight lander measured the speed of seismic waves in the Martian crust. The presence of ice and water affects seismic velocity. We argue that the measurements preclude a layer of ice-filled crust that confines liquid water in an aquifer. Key points • We interpret the seismic wave velocity of the Martian crust measured by InSight. • We quantity the effects of ice and water on seismic velocity using a rock physics model. • Measurements preclude a layer of ice-filled upper crust that confines liquid water in an aquifer. 1. Introduction Large volumes of water are hypothesized to have carved and passed through the Martian outflow channels (e.g., Baker, 2001). Because these channels originate from discrete sources, a groundwater origin is typically invoked (e.g., Head et al., 2003). Given the large discharges needed to create the observed landforms, in some cases a couple orders of magnitude greater than the largest catastrophic floods on Earth (Baker, 1982), large and permeable aquifers would be needed (e.g., Carr, 1979; Manga 2004). While most of the outflow channels are Hesperian (e.g., Tanaka, 1997), their formation continued through the Amazonian (e.g., Rodriguez et al., 2015). Some of the youngest channels originated from fissures in Eastern Elysium Planitia within the past 10s of millions of years (Burr et al., 2002; Voight and Hamilton, 2017). The subsurface of Mars thus appears to have hosted and episodically released large volumes of water over most of Martian history. Hence, detecting the presence and quantifying the volume of subsurface water and ice would help constrain the water budget and cycle from the Noachian to present (Clifford and Parker, 2001). To discharge water at the surface, aquifers must have sufficient pressure for water to reach the surface. One way to achieve hydraulic heads greater than hydrostatic and hence enable surface discharge is to confine aquifers beneath an overlying ice-saturated crust or cryosphere (e.g.

show abstract

“…Wang et al, 2022;Wilcock, 2001) and in the laboratory (e.g., Bartlow et al, 2012;Beeler & Lockner, 2003;Chanard et al, 2019;Noël et al, 2019). We expect a larger response for smaller 𝐴𝐴 𝐴𝐴𝐴𝐴 (e.g., Ader et al, 2014;Beeler & Lockner, 2003;Heimisson & Avouac, 2020). To estimate the periodic variations of seismicity rate in the Westmorland area (latitude 32.98°-33.12°N, longitude 115.50°-115.65°W), we use the Quake Template Matching seismicity catalog (Ross, Trugman, et al, 2019).…”

Section: Estimating the Friction Parameter And Stress Conditionsmentioning

confidence: 99%

The 2020 Westmorland, California Earthquake Swarm as Aftershocks of a Slow Slip Event Sustained by Fluid Flow

et al. 2022

Self Cite

View full text Add to dashboard Cite

Earthquakes are often seen to cluster in time and space. Many clusters have a clearly identifiable mainshock followed by numerous smaller aftershocks. Others occur as a sustained burst of small magnitude earthquakes lasting from hours to several years without an obvious mainshock, referred to as a swarm (Mogi, 1963). The peak seismicity rate during swarms can reach >10,000 times the background level with complex temporal evolution that cannot be explained by the simple Omori-Utsu type power-law decay (Omori, 1894;Utsu, 1961) typical of mainshock-aftershock sequences (Holtkamp & Brudzinski, 2011;Vidale & Shearer, 2006). Swarms also often expand spatially (X. Chen et al., 2012) with a velocity ranging from m/day (e.g., Ross et al., 2020) to km/hr (e.g., Roland & McGuire, 2009). Swarms can occur in a wide range of geological settings, such as volcanoes (e.g.,

show abstract

Analytical Prediction of Seismicity Rate Due to Tides and Other Oscillating Stresses

Abstract: • We derive a simple analytical model for seismicity rate based on rate-and-state friction • The model can be applied to perpetually oscillating stresses on earth and other solid-surface bodies • We reevaluate recent work on possible tidally triggered seismicity on Mars

Cited by 20 publications

References 42 publications

No Cryosphere‐Confined Aquifer Below InSight on Mars

No Cryosphere‐Confined Aquifer Below InSight on Mars

No cryosphere-confined aquifer below InSight on Mars

The 2020 Westmorland, California Earthquake Swarm as Aftershocks of a Slow Slip Event Sustained by Fluid Flow

Contact Info

Product

Resources

About