2 1/2 and 3 dimensional interpretation of magnetic anomalies in the central-southern Pyrenees (Spain)

Abstract

Available aeromagnetic data have been used to interprete magnetic anomalies using 2 1/2 and 3 D techniques in an area that includes parts of the Axial Zone and of the South Pyrenean Thrust Sheets in the Spanish Pyrenees. The interpretation has been made with the help of field magnetic susceptibility measurements. The dip of the Ebro Basin basement to the north has been inferred for part of the magnetic profile. Large magnetically disturbing bodies with the top at about sea level can be interpreted as a stack of Paleozoic basement thrusts or, alternatively, as an accumulation of Triassic volcanic rocks. Some smaller anomalies are clearly associated with outcropping or buried basaltic rocks (ophites). The disposition of major magnetic anomalies suggests that shear movement may have affected part of the studied area.