Pore Pressure Drop During Dynamic Rupture and Conditions for Dilatancy Hardening

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985858%3A_____%2F23%3A00573882" target="_blank" >RIV/67985858:_____/23:00573882 - isvavai.cz</a>

Alternative codes found

RIV/44555601:13440/23:43897742

Result on the web

<a href="https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2023JB026396?src=getftr" target="_blank" >https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2023JB026396?src=getftr</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1029/2023JB026396" target="_blank" >10.1029/2023JB026396</a>

Result language

angličtina

Original language name

Pore Pressure Drop During Dynamic Rupture and Conditions for Dilatancy Hardening

Original language description

Pore pressure drop brought about by fault dilatancy during accelerating slip may suppress nucleation of earthquakes. Yet, direct measurements of pore pressure during dynamic slip are challenging to produce. We present results of a physics-based model simulating onset of slip in saturated granular layers coupled to a constant fluid pressure reservoir. Grain rearrangements required for slip to commence induce incipient rapid dilatation during which the maximum pore pressure drop is generated. We find that up to a critical slip rate the pore pressure drop is consistent with a prediction derived for an incompressible fluid flow. In this drained regime, excess pore pressure is efficiently relaxed and has little effect on slip stability. Above the critical slip rate, marking the onset of undrained conditions, the pore pressure drop decays slowly, inhibits dilatation rate, and significantly increases strength of the layer, stabilizing the rupture growth. The magnitude of the pore pressure drop increases monotonically with the drainage number given as the ratio of the dilatation rate to a characteristic fluid infiltration rate. The pore pressure drop in the undrained regime also depends on a second non-dimensional parameter, urn:x-wiley:21699313:media:jgrb56355:jgrb56355-math-0001, where β is storage capacity, and urn:x-wiley:21699313:media:jgrb56355:jgrb56355-math-0002 is the effective normal stress. Low values of this parameter enhance localization of strain near the drained boundaries of the layer, promoting fluid flow into the layer. Our results can be used to better constrain drainage conditions associated with changes in slip rate, the magnitude of the generated pore pressure and the corresponding fault strengthening.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10505 - Geology

Project

<a href="/en/project/GJ19-21114Y" target="_blank" >GJ19-21114Y: Granular mechanics of dynamically-triggered earthquakes</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Geophysical Research-Solid Earth

ISSN

2169-9313

e-ISSN

2169-9356

Volume of the periodical

128

Issue of the periodical within the volume

7

Country of publishing house

US - UNITED STATES

Number of pages

30

Pages from-to

e2023JB026396

UT code for WoS article

001042049100001

EID of the result in the Scopus database

2-s2.0-85164031833