Drainage Pattern and Fault Growth within the Easternmost End of the Gulf of Corinth; Greece

Vasiliki Zygouri¹, Ioannis Koukouvelas¹, and Gerassimos Papadopoulos^2
1University of Patras, Patras, Greece
²National Observatory of Athens, Athens, Greece

The Gulf of Corinth, in Greece, is a 130-km long by 30-km wide asymmetric graben that is delineated on its margins by large scale roughly E – W trending normal fault systems. The primitive cause of growth of these fault systems is the interaction and linkage of normal fault segments. Our study focuses at three representative areas of the eastern Gulf of Corinth, which are, the Sofiko area, the Kenchriae – Athikia area and the offshore Xylokastro – Kiato area. Dense drainage pattern as is analyzed by using remote sensing of air photographs as well mesoscopic structural analyses give insights into the spatial characteristics of the fault zones at particular stages of their evolution. The ability of stream courses to accommodate rapidly changing topography constitutes a particular key marker of fault growth by segment linkage. Fault's segment linkage resulted in a redistribution of displacement with the loci of faulting being transferred from the center of each segment onto the center of the breaching fault. As a consequence river course change and this cause changes in the depositional environment and the depocenter of the basin. Such changes are denoted within the study area by reverse of drainage pattern in the Sofiko area or by the incision of streams through uplifted footwalls of predominant fault segments that coalesce into a large alluvial plain in Corinthos area. In similar U –shaped canyons cutting through gently dipping slopes formed at transfer zones in the offshore Xylokastro – Kiato area. Our study tries to demonstrate that drainage pattern analysis shed light to the evolution of fault arrays, and gives lines of evidence into the relative linkage mechanism of fault segments during profile readjustment that cannot be obtained through structural analysis of fault geometry.

AAPG Search and Discovery Article #90072 © 2007 AAPG and AAPG European Region Conference, Athens, Greece