Reactions between fluids and rocks have a fundamental impact on many of the natural and geo-engineering processes in crustal settings. Examples of such natural processes are localization of deformation, earthquake nucleation caused by high pressure fluid pulses, as well as metamorphic reactions and rheological weakening triggered by fluid flow, metasomatism and fluid-mediated mass transport. Moreover, the efficiency of many geo-engineering processes is partly dependent on fluid-rock interactions, such as hydraulic fracturing, geothermal energy recovery, CO2 storage and wastewater injection. All our observations in the rock record are the end-product of all metamorphic, metasomatic and deformation changes that occurred during the interaction with fluid. Therefore, to investigate and understand these complex and interconnected processes, it is required to merge knowledge and techniques deriving from several disciplines of the geosciences.
We invite multidisciplinary contributions that investigate fluid-rock interactions throughout the entire breadth of the topic, using fieldwork, microstructural and petrographic analyses, geochemistry, experimental rock mechanics, thermodynamic modeling and numerical modeling.

This session welcomes contributions from geophysical, geochemical, microbial, numerical, and laboratory studies to promote a better understanding of geological processes and Life in modern and fossil extreme environments, with a special emphasis on mud volcanoes and hydrothermal systems. We encourage multidisciplinary studies related to environments that promoted Life emergence on the Hadean Earth both in past and present extreme terrestrial environments including planetary analogues. We welcome discussion about new approaches to detect and characterise Life in such conditions ranging from biology to geophysics. This also includes geochemical, geological and multidisciplinary datasets investigating piercement structures and their geochemical reactions occurring at depth and at the surface as well as microbiological studies. The session will also discuss the effects of extreme environments on palaeo-climate and how external forcing may affect such systems.

Public information:
Dear Authors,

in order to facilitate the exchange of information during the chat session, we have divided the contributions by topics and accordingly we proposed an attendance time (see below). We wish you all a productive EGU conference.

BG5.3 convenors
--------------------------------------------------------------------------------------

----------------------------------------------------------------------
Attendance time: Tuesday, 05 May 08:30–10:15

D796 |
EGU2020-3344
| Highlight
The effects of climate change on the Atacama Desert as a pertinent Mars analog model
Armando Azua-Bustos and Alberto G. Fairén

D797 |
EGU2020-12720
A characterization of microbial diversity in the Winter Wonderland Ice Cave, Uinta Mountains, Utah, USA
Miranda Seixas, Erin Eggleston, Jeffrey Munroe, and David Herron

D798 |
EGU2020-12203
Linking decay of microbial mats and dolomite formation in the sabkhas of Qatar
Zach Diloreto, Maria Dittrich, Tomaso Bontognali, Hamad Al Saad Al Kuwari, and Judith A. McKenzie

D799 |
EGU2020-1581
The waterbodies of the Dallol volcano: A physico-chemical and geo-microbial survey
Hugo Moors, Miroslav Honty, Carla Smolders, Ann Provoost, Mieke De Craen, and Natalie Leys

D813 |
EGU2020-3003
Detecting microbial pigments from gypsum using Raman spectroscopy: from field prospection to laboratory studies
Jan Jehlicka, Kateřina Němečková, and Adam Culka

D814 |
EGU2020-12335
The characteristics of microbial communities along the littoral gradient of a proglacial lake in Qinghai-Tibet Plateau
Meiqing Lu, Xin Luo, Jiu Jimmy Jiao, Hailong li, Xingxing Kuang, Rong Mao, Xiaoyan Shi, and Yuqing Feng

D815 |
EGU2020-667
The ferruginous, sulfate-rich hypolimnion of a post-mining lake as an analogue to disentangle redox cycling in Paleoproterozoic coastal zones
Daniel Petráš, Christophe Thomazo, and Stefan Lalonde

D816 |
EGU2020-20279
Detection of sulphuric life in Mars analogue material using a miniature LIMS system
Andreas Riedo, Valentine Grimaudo, Joost W. Aerts, Alena Cedeño López, Marek Tulej, Pascale Ehrenfreund, and Peter Wurz


----------------------------------------------------
Attendance time: Tuesday, 05 May 10:45–12:30


D800 |
EGU2020-15205
New insights into the magmatic system southeast of El Hierro from high-resolution 2D seismic data
Kai-Frederik Lenz, Felix Gross, Andreas Klügel, Rachel Barrett, Philipp Held, Katja Lindhorst, Paul Wintersteller, and Sebastian Krastel

D801 |
EGU2020-3673
| Highlight
Earthquake triggering of mud volcanoes and fluid seepage systems in fold-and-thrust belts and subduction zones
Marco Bonini and Daniele Maestrelli

D802 |
EGU2020-1271
Peculiarities of mud volcanism in Lake Baikal
Grigorii Akhmanov, Adriano Mazzini, Oleg Khlystov, Alina Kudaeva, and Olesia Vidishcheva

D803 |
EGU2020-16565
Different pockmark systems and their potential importance for the hydrological and biogeochemical balance of a peri-alpine lake
Adeline N.Y. Cojean, Maciej Bartosiewicz, Jeremy Zimmermann, Moritz F. Lehmann, Katrina Kremer, and Stefanie B. Wirth

D804 |
EGU2020-4840
Internal Structure of Venere Mud Volcano in the Crotone Forearc Basin, Calabrian Arc, Italy, from Multibeam Bathymetry, Wide-Angle and Multichannel Seismic Data
Michael Riedel, Anne Krabbenhoeft, Cord Papenberg, Joerg Bialas, Gerhard Bohrmann, and Silvia Ceramicola

D805 |
EGU2020-3664
Tectonic structures vs genesis and activity of mud volcanoes: examples from Emilia and Marche (Northern Apennines, Italy)
Marco Bonini, Daniele Maestrelli, and Federico Sani

D806 |
EGU2020-1336
A shallow mud volcano in the sedimentary basin off the Island of Elba
Alessandra Sciarra, Anna Saroni, Fausto Grassa, Roberta Ivaldi, Maurizio Demarte, Christian Lott, Miriam Weber, Andi Eich, Ettore Cimenti, Francesco Mazzarini, and Massimo Coltorti

D807 |
EGU2020-1315
Explosive mud volcano eruptions and rafting of mud breccia blocks
Adriano Mazzini, Grigorii Akhmanov, Manga Michael, Alessandra Sciarra, Ayten Khasayeva, and Ibrahim Guliyev

D808 |
EGU2020-5213
Palynology of Holocene Lake Baikal sediments
Alienor Labes, Adriano Mazzini, Grigorii G. Akhmanov, and Wolfram M. Kürschner

D809 |
EGU2020-20934
Integrated analysis of geophysical and geochemical data from cold fluid seepage system along the Gydratny Fault (Lake Baikal)
Olesya Vidischeva, Marina Solovyeva, Evgeniya Egoshina, Yana Vasilevskaya, Elena Poludetkina, Grigorii Akhmanov, Oleg Khlystov, and Adriano Mazzini

D810 |
EGU2020-1741
Geochemistry of oil-and-gas seepage in Lake Baikal: towards understanding fluid migration system
Evgeniya Egoshina, Michail Delengov, Olesya Vidishcheva, Elena Bakay, Natalya Fadeeva, Grigorii Akhmanov, Adriano Mazzini, and Oleg Khlystov

D811 |
EGU2020-4413
Concentrations and behavior of rare earth elements in mud volcanic waters
Alexey Sobisevich, Valery Ershov, Evgeniy Elovskiy, Elnur Baloglanov, and Irina Puzich

D812 |
EGU2020-3307
Borate accumulations related to onshore mud volcanism: Case study from the Kerch Peninsula, the Caucasus collision zone
Ellina Sokol, Svetlana Kokh, Olga Kozmenko, and Vasili Lavrushin

Fractures and faults are common tectonic features within shallowly deformed rocks. Fracture networks play a fundamental role in fluid migration. Understanding the mechanical and chronological development of fracture networks is therefore key for tectonic studies as well as for resources exploration and waste repositories studies.
Fractures and faults are witnesses of the medium history, resulting from processes controlled by physical forces and/or chemical potential. A better understanding of the parameters that control fracture complexity in rocks will lead to new tools for reconstructing crustal-scale processes such as fluid flow and fluid-rock interactions, paleostress evolution and earthquake tectonics. However, the great challenge is the understanding of dynamic feedbacks between fluid flow, permeability rise/fall, chemical reactions and rock failure. Fluid sources, fluid flow and fluid-rock interactions vary spatially and temporally as a function of basin and reservoir structural evolution, altering the physical/mechanical properties of fractures and host rocks.
Fractures form at all stages of rock history, from early diagenesis/burial to major deformation events. Building realistic conceptual and predictive models of fracture types and occurrence therefore requires recognition of fractures formed prior to, and during deformation events. A blind spot in fracture analysis has been for long the lack of constraints on the absolute timing of brittle failure and structural diagenesis. Recent progress in absolute dating of calcite cements/coatings of veins/faults has proven the relevance of meso-structures to regional structural evolution, allowing for a refined tectonic history. New steps forward include a better appraisal of the rate of development and lifetime of individual fracture and fracture sets, and of the timing and rate of fluid flow in fractured rocks.
This session aims at bringing together scientists working in the field, in the lab, and on simulations to foster discussion towards improving our understanding of (1) the mechanics, occurrence, timing and stress history of fractures in upper crustal rocks, and (2) the role fracture networks play on subsurface fluid flow. We welcome contributions from all fields, including structural geology, mechanics, isotope geochemistry, and hydrogeology that aim at comprehending the development of fracture systems in time and space and their co-evolution with fluid flow in a variety of geological settings.

Dissolution, precipitation and chemical reactions between infiltrating fluid and rock matrix alter the composition and structure of the rock, either creating or destroying flow paths. Strong, nonlinear couplings between the chemical reactions at mineral surfaces and fluid motion in the pores often leads to the formation of intricate patterns: networks of caves and sinkholes in karst area, wormholes induced by the acidization of petroleum wells, porous channels created during the ascent of magma through peridotite rocks. Dissolution and precipitation processes are also relevant in many industrial applications: dissolution of carbonate rocks by CO2-saturated water can reduce the efficiency of CO2 sequestration, mineral scaling reduces the effectiveness of heat extraction from thermal reservoirs, acid rain degrades carbonate-stone monuments and building materials.

With the advent of modern experimental techniques, these processes can now be studied at the microscale, with a direct visualization of the evolving pore geometry. On the other hand, the increase of computational power and algorithmic improvements now make it possible to simulate laboratory-scale flows while still resolving the flow and transport processes at the pore-scale.

We invite contributions that seek a deeper understanding of reactive flow processes through interdisciplinary work combining experiments or field observations with theoretical or computational modeling. We seek submissions covering a wide range of spatial and temporal scales: from table-top experiments and pore-scale numerical models to the hydrological and geomorphological modelling at the field scale. We also invite contributions from related fields, including the processes involving coupling of the flow with phase transitions (evaporation, sublimation, melting and solidification).

Public information:
There will be a zoom session connected with the session on Tue, May 5th, at 18.00 CET

https://us04web.zoom.us/j/79628870111