Active tectonics on Deception Island (West-Antarctica): A new approach by using the fractal anisotropy of lineaments, fault slip measurements and the caldera collapse shape

The tectonic field on Deception Island (South Shetlands, West Antarctica) is determined from structural and
fractal analyses. Three different analyses are applied to the study of the strain and stress fields in the area: (1) field
measurements of faults (strain analysis), (2) fractal geometry of the spatial distribution of lineaments and (3) the caldera
shape (stress analyses). In this work, the identified strain field is extensional with the maximum horizontal shortening
trending NE-SW and NW-SE. The fractal technique applied to the spatial distribution of lineaments indicates a stress
field with SHMAX oriented NE-SW. The elliptical caldera of Deception Island, determined from field mapping, satellite
imagery, vents and fissure eruptions, has an elongate shape and a stress field with SHMAX trending NE-SW.