Uplift and slip rates of the eastern Eliki fault segment, Gulf of Corinth, Greece, inferred from Holocene and Pleistocene terraces

Abstract

Uplifted Pleistocene and Holocene marine and fluvial deposits are preserved in the footwall of the Eliki fault, western Gulf of the Corinth, where geodetic extension rates exceed 10 mm a-1. Up to 10 Pleistocene terraces are distinguished in the footwall block of the eastern Eliki fault segment, discontinuously preserved along strike. Terraces are depositional, forming by the progradation of clastic fan deltas, or predominantly erosional, between fan deltas. Correlation of terrace profiles with Late Pleistocene eustatic sea level suggests an uplift rate of c. 1 mm a-1, with an alternative of c. 1.5 mm a-1. On average, higher rates are obtained from uplifted Holocene deposits (c. 1–2 mm a-1). To determine slip rates, a long-term ratio of uplift to subsidence of c. 1:2–3.2, derived from net footwall altitude and basin subsidence–fill and a fault dip of 50° are applied to uplift of c. 1 mm a-1. These produce a slip rate of c. 4–7 mm a-1 contributing c. 2–4 mm a-1 to extension across the Gulf, significantly less than geodetic rates. This discrepancy may result from strain taken up on faults to the north and offshore. Uplift rates decrease little at the Eliki fault tips. Uplift rates are broadly consistent in the central–western Gulf but show a decrease in average uplift from Corinth eastward