Temporal and spatial correlations between soil CO2 flux and crustal stress. Issue 10 (9th October 2016)

• Record Type: Journal Article
• Authors: Camarda, Marco; De Gregorio, Sofia; Di Martino, Roberto M. R.; Favara, Rocco
• Is Part Of: Journal of geophysical research. Volume 121:Issue 10(2016:Oct.)
• Page Start: 7071
• Page End: 7085
• Publication Date: 2016-10-09
• Subjects: Soil CO2 flux -- Crustal stress -- seismotectonic process; Geomagnetism -- Periodicals; Geochemistry -- Periodicals; Geophysics -- Periodicals; Earth sciences -- Periodicals; 551.1
• DOI: 10.1002/2016JB013297
• Languages: English
• ISSNs: 2169-9313

Abstract

Abstract: In seismically active areas, tectonic stress deforms and breaks the rocks of the crust. Ongoing deformation produces detectable modifications in the shallower portions of the crust, resulting in a wide variety of changes in several parameters. In this paper, we report the results of a large‐scale spatial (across an area of 15, 000 km 2 ) and temporal (up to 3 years) investigation of the relationship between active crustal stress and soil CO2 flux. We deployed a network of 10 automatic stations in most of the seismically active districts of southern Italy to monitor the soil CO2 fluxes, and we used seismicity data to track crustal stress. The results of the investigation show that the CO2 flux signals varied independently in the districts with low and sporadic seismicity. Conversely, in the only district with nearly continuous seismic activity, almost all of the CO2 flux signals were well correlated with each other, and we recorded a clear synchronous sharp increase of the seismicity and signals recorded by several stations. The high spatial and temporal correlation between seismicity and gas discharge evidenced in this study prove that the crustal stress associated with the seismogenic process is able to effectively modulate the gas release in a seismically active area. Key Points: First investigation between crustal stress and soil CO2 flux relationship on broad spatial and temporal scale. Clear evidence of connection between soil CO2 flux variations and the action of crustal stress Experimental proof of the variations of fluid release associated to seismogenic process