Gocad modelling of self-potential data for 3-D reconstitution of soil heterogeneity and paleo-channels in the Rhone river delta.

@inproceedings{BileGM2009,
 abstract = { The heterogeneity of soil and sedimentation in the deltas and plains with small relief makes difficult the mapping of soil and surface formations. The gOcad geomodel has long been recognized as an appropriate tool to reconstruction of 3D architectures in fundamental geology and geology engineering for minerals and oil prospection. gOcad is applied here, in a deltaic environment, in the Camargue, for interpretation and visualization of geoelectrical data of self-potential (SP). The SP anomalies are related to the heterogeneity of salinity of water and hydraulic conductivity of soils and sediments. gOcad allows thus the 3D cartography of the system, and the description of a paleochannel. In this 3D model, a threshold value of SP close to - 5 mV allows to map the lateral boundaries of the paleochannel. In addition, the values of SP anomalies more negative (from - 15 mV to - 20 mV) indicate more strong electro-kinetic effects, influenced by ground water flow inside the paleochannel (streaming potential), the presence of fast circulation zones, lenses with greater hydraulic conductivity, gradients of salinity (salted bevel/fresh water). Moreover, the SP method is non-destructive. This application shows the interest to combine gOcad and geophysical measurements for morphological characterization of underground structures and hydrogeologic and agronomic applications. },
 author = { Bile, Raymond AND Viseur, Sophie AND Trolard, Fabienne AND Revil, A. AND Bourrie, G. },
 booktitle = { Proc. 29th Gocad Meeting, Nancy },
 title = { Gocad modelling of self-potential data for 3-D reconstitution of soil heterogeneity and paleo-channels in the Rhone river delta. },
 year = { 2009 }
}