Search results for "Caprock"
showing 4 items of 4 documents
Experimental assessment of the hydro-mechanical behaviour of a shale caprock during CO2 injection
2021
Abstract The presented experimental study focuses on the hydro-mechanical characterisation of a shale caprock (Opalinus Clay) in contact with carbon dioxide. The objective of this paper, consists in the evaluation of the material's sealing capacity in terms of entry-pressure, mechanical behaviour and sensitivity of the transport properties to chemo-mechanical effects induced by gaseous and liquid CO2 injection. Two types of Opalinus Clay core samples are tested; shaly and carbonate-rich. The sealing capacity has been evaluated on the shaly OPA according to the stepwise and the residual methods and compared to the results from mercury intrusion porosimetry. The obtained results and the diffe…
Thermo‐Hydro‐Mechanical Model and Caprock Deformation Explain the Onset of an Ongoing Seismo‐Volcanic Unrest
2021
Acknowledgments The authors are grateful to the Editor, Prof. Ben‐Zion Yehuda, and the reviewers: Prof. Micol Todesco and an anonymous reviewer, whose comments and recommendations have significantly improved the quality of this work. The authors acknowledge the financial support of the Petroleum Technology Development Fund (PTDF) Nigeria for this research. The comparison of our models with monitoring data was made possible by the outstanding efforts of the staff at the INGV‐Osservatorio Vesuviano, who provide weekly information about geophysical parameters at the Campanian volcanoes (http://www.ov.ingv.it/ov/en/bollettini/272-campi-flegrei-bollettini-settimanali.html). The authors are parti…
Three-dimensional kernel-based coda attenuation imaging of caldera structures controlling the 1982-84 Campi Flegrei unrest
2019
Abstract Coda-wave attenuation imaging has risen as a state-of-the-art technique to depict volcanic structures using their dispersion effects. The 1982–84 seismic and deformation unrest at Campi Flegrei caldera (Italy) is a unique example of non-eruptive volcanic activity in a structured caldera. Here, we propose the first application of 3D coda-attenuation kernels to image caldera structures at multiple frequencies during unrest. Using sensitivity kernels is necessary to assess the effective resolution of coda imaging in highly heterogeneous volcanoes. The technique relies on the solution of Paasschens' equations in the framework of radiative transfer theory. The results map coda attenuati…
Hot water injection in relation to 1982-84 microseismic events at Campi Flegrei Caldera by thermo-hydro-mechanical simulation
2020
The repeated deformations and seismic unrests at Campi Flegrei caldera (southern Italy) have been identified due to a fluid injection source in volcano active area. We investigated the role of hot water injection in the seismic unrests of 1982-1984 with a view to gaining insights into the caldera’s dynamics, by applying coupled TOUGHREACT-FLAC3D simulator to our computational domain of 10 × 1 × 3 km with a single-phase steam isothermal (HM) and non-isothermal (THM) simulations comparison. The results indicated that the overlying caprock blocks the uprising hot water injection, leading to the building up of pore pressure and shear stress underneath over time. This process substantially modif…