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<p>Estimados,</p>
<p>Los invitamos hoy a asistir a la siguiente Charla Especial dentro
del marco de Profesores Visitantes organizado por FCAG, a las 16
hs en el Salón Meridiano.</p>
<p>Atentamente,</p>
<p>Secyt - FCAG</p>
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<p><b style="font-weight:normal;"
id="docs-internal-guid-c411744a-a5a0-0718-7c0b-53cc330885a4"> </b></p>
<p dir="ltr"
style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><b
style="font-weight:normal;"
id="docs-internal-guid-c411744a-a5a0-0718-7c0b-53cc330885a4"><span style="font-size:12pt;font-family:Verdana;color:#000000;background-color:transparent;font-weight:700;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">Charla Especial: </span><span style="font-size:12pt;font-family:Verdana;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">Damien Jougnot</span></b></p>
<b style="font-weight:normal;"
id="docs-internal-guid-c411744a-a5a0-0718-7c0b-53cc330885a4">
<p dir="ltr"
style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:12pt;font-family:Verdana;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">CNRS, Sorbonne Universités, UPMC Univ Paris 06, UMR 7619 Metis, Paris, France</span></p>
<br>
<p dir="ltr"
style="line-height:1.2;margin-top:0pt;margin-bottom:0pt;text-align:
justify;"><span style="font-size:12pt;font-family:Verdana;color:#000000;background-color:transparent;font-weight:700;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">Título</span><span style="font-size:12pt;font-family:Verdana;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">: Impact of small-scale saline tracer heterogeneity on electrical resistivity monitoring: insight from a geoelectric millifluidic experiment.</span></p>
<br>
<p dir="ltr"
style="line-height:1.2;margin-top:0pt;margin-bottom:0pt;text-align:
justify;"><span style="font-size:12pt;font-family:Verdana;color:#000000;background-color:transparent;font-weight:700;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">Resumen</span><span style="font-size:12pt;font-family:Verdana;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">:Time-lapse electrical resistivity tomography is a widely used geophysical method to remotely monitor water saturation and the migration of contaminant plumes. The effects of heterogeneous solute concentrations below the resolution limits of the tomogram are commonly ignored. We have adapted an experimental set-up to study the effects of sub-resolution solute heterogeneities on the effective bulk electrical resistivity. We performed saline tracer tests under full and partial water saturations. The unsaturated flow was imposed by jointly injecting air and water. The bulk resistivities measured at the scale of the medium were confronted to resistivities computed numerically from the measured spatial distributions of the fluid phases and the salinity field. We find that the air distribution, saline tracer channeling and fingering, and mixing phenomena all result in large changes in the measured and simulated bulk resistivities by creating preferential flow paths or barriers for electric current at the pore scale. Based on these findings, we postulate that sub-resolution effects contribute to one of the most important inconsistencies in conventional time-lapse ERT imaging, namely the apparent loss of tracer mass. </span></p>
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