Fault mirrors in seismically active fault zones: A fossil of small earthquakes at shallow depths

Inelastic response of compliant fault zones to nearby earthquakes

[1] Using dynamic rupture models, we examine the response of compliant fault zones that surround pre‐existing faults to nearby earthquakes. We find that some portions of a compliant fault zone can experience inelastic deformation due to dynamic stress perturbations, while the remaining portions deform elastically. Inelastic response of the fault zone results in sympathetic fault‐parallel motion...

Resolving Fault Plane Ambiguity for Small Earthquakes

Earth tides can trigger shallow thrust fault earthquakes.

We show a correlation between the occurrence of shallow thrust earthquakes and the occurrence of the strongest tides. The rate of earthquakes varies from the background rate by a factor of 3 with the tidal stress. The highest correlation is found when we assume a coefficient of friction of mu = 0.4 for the crust, although we see good correlation for mu between 0.2 and 0.6. Our results quantify ...

CO2/Brine transport into shallow aquifers along fault zones.

Unintended release of CO(2) from carbon sequestration reservoirs poses a well-recognized risk to groundwater quality. Research has largely focused on in situ CO(2)-induced pH depression and subsequent trace metal mobilization. In this paper we focus on a second mechanism: upward intrusion of displaced brine or brackish-water into a shallow aquifer as a result of CO(2) injection. Studies of two ...

Characterization of Fault Zones

There are currently three major competing views on the nature of earthquake fault zones. The first is that faults are (possibly segmented and heterogeneous) Euclidean zones in a continuum solid. The second focuses on granular aspects of faults and deformation fields. The third is that faults are fundamentally rough fractal objects at all relevant scales. The existing data can not distinguish un...