The southern Aegean seafloor exhibits clear evidence of internal deformation (stretching) as shown by tectonics, seismology, and space geodesy. We use an analog three-layer laboratory experiment of sand, silicon putty, and honey to investigate the deformation of the southern Aegean lithosphere. The model is installed in a box and confined by a vertical wall. We open the gate and observe the deformation of the two upper layers due to buoyancy forces. The general pattern of deformation of the southern Aegean is found in the analog model. We observe the formation of an arc spreading outward with time; the extension is radial in the inner part but parallel to the arc in the external part and of comparable importance. At both ends of the gate we observe strike-slip motion (dextral in the western part, sinistral in the eastern part). Rotation (clockwise in the western part, counterclockwise in the eastern part) of up to 40 degrees is seen on both sides of the gate but also present, with a smaller amplitude, far in the internal region, partially due to distributed shear. The spreading is associated with the thinning of the two upper layers and affects a region of dimensions comparable to the length of the free boundary. This spreading does not propagate inward with time. Some pieces of material located near the active boundary remain undeformed during the experiment.
AGU Index Terms: 8110 Continental Tectonics; 1209; 8155 Plate motions-general
Keywords/Free Terms: Geodynamics of the Aegean
JGR-Solid Earth 96JB02594
Vol. 102
, No. B1
, p. 649