Publications associées à Roche ultramafique

Elongated hydraulic fracture emerging from layers of alternating fracture toughness

Brice Tanguy Alphonse Lecampion, Carlo Peruzzo

Whether used to enhance the hydrocarbon production from low permeability rocks or to measure the minimum in-situ principal stress in rock formations, height growth of a hydraulic fracture above the formation of interest is a key metric for the design of su ...

2023

The influence of water-saturation on the strength of volcanic rocks and the stability of lava domes

Marie Estelle Solange Violay, Michael Heap

The rocks forming a volcanic edifice or dome are typically saturated or partially-saturated with water. However, most experiments aimed at better understanding the mechanical behaviour of volcanic rocks have been performed on dry samples, and therefore mos ...

2023

Experimental plastic reactivation of pseudotachylyte‐filled shear zones

Marie Estelle Solange Violay, François Xavier Thibault Passelègue

Pseudotachylytes are fine‐grained fault rocks that solidify from melt that is produced in fault zones during earthquakes. Exposed sections of natural fault zones reveal evidence of post‐seismic plastic deformation (i.e. reactivation) of pseudotachylyte, wh ...

2021

Rock strength properties of granitic rocks in Yosemite Valley, Yosemite National Park, California

Federica Sandrone, Michel Jaboyedoff

Yosemite National Park, located in the central part of California’s Sierra Nevada mountains, is a glacially carved landscape filled with iconic rock formations such as Cathedral Peak, El Capitan, and Half Dome. Igneous rocks, consisting primarily of variat ...

U.S. Geological Survey2020

Taking the pulse of volcanic eruptions using plagioclase glomerocrysts

Anders Meibom, Stéphane Laurent Escrig, Anders McCarthy, Pierre Vonlanthen

Crystallization timescales in subvolcanic systems and the consequences of interaction between ascending magmas and gases remain largely unconstrained, as do links between these processes and monitoring signals at restless volcanoes. We apply diffusion chro ...

ELSEVIER2020

Seismic and Microseismic Signatures of Fluids in Rocks: Bridging the Scale Gap

Lucas Xan Pimienta, Christian David

The aim of this collection is to record a snapshot of our current state of understanding of the impact of fluids on the evolution and monitorability of subsurface rock formations during anthropogenic fluid injection/withdrawal operations, accounting for sc ...

AMER GEOPHYSICAL UNION2019

Seismic Dispersion and Attenuation in Fluid-Saturated Carbonate Rocks: Effect of Microstructure and Pressure

Lucas Xan Pimienta

The frequency dependence of seismic properties of fully saturated rocks can be related to wave-induced fluid flows at different scales. The elastic dispersion and attenuation of four fluid-saturated carbonate rocks, with different microstructures, have bee ...

2019

Anomalous Vp/Vs ratios at seismic frequencies might evidence highly damaged rocks in subduction zones

Marie Estelle Solange Violay, Lucas Xan Pimienta

Unusually high compressional (P) to shear (S) wave velocity ratios (V-p/V-s) were measured at different subduction zones and interpreted as fluid-pressurized regions. Because no laboratory data reported such high values in isotropic rocks, mineralogical or ...

2018

Supercritical CO2 injection and residence time in fluid-saturated rocks: Evidence for CO2 and mineral dissolution and effects on rock integrity

Lucas Xan Pimienta, Ke Liu

CO2 injection and storage in geological reservoirs is an attractive prospect for mitigating the anthropogenic production of greenhouse gases and global warming. The technology could lead to mineral precipitation and therefore stable storage over geological ...

Elsevier Sci Ltd2017

Vertical changes of the Co and Mn speciation along a lateritic regolith developed on peridotites (New Caledonia)

Gabrielle Dublet, Vincent Noel

Because they can host significant amounts of Co, the Mn-oxides are commonly considered as the major Co-bearing mineral species in lateritic environments. However, little is known about the process leading to the formation and/or the weathering of these Co- ...

Pergamon-Elsevier Science Ltd2017