Figure 7
From: Three-dimensional inversion of magnetotelluric data from the Central Andean continental margin
3-D model (RMS = 1.91) of the forearc (area C). Background resistivity was set to 1,000 Ωm. PO, Pacific Ocean with a resistivity of 0.3 Ωm; CC, Coastal Cordillera; LV, Longitudinal Valley; J, connection with the Pacific Ocean and highly conductive anomalies in the Longitudinal Valley and near Chacarilla canyon; K, near Chacarilla canyon. (a) A plan view at a depth of 3.2 km of the resistivity distribution. Near-surface structures partly connect to the Pacific Ocean and force currents to flow around sites, resulting in phases leaving the quadrant (c.f. (Ichihara and Mogi2009)). Black dots: sites with phases >90°. (b) Resistivity distribution with depth along investigation area C at latitude 21 °S. Beneath 12-km depth, the 3-D model resembles a rather homogeneous, poorly conducting half-space (L). K, K1, K2 - West Fissure zone.