2018/04/23 by Silke Mechernich, Sascha Schneiderwind, Jack Mason +6 · 1 voice · 2 citations
Earth and Planetary Sciences · #earthquake and tectonic studies #Geology and Paleoclimatology Research #Geological and Geochemical Analysis
paper · pdf · doi:10.1029/2017jb014600
openalex publication_date 2018/04/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/12
Abstract The deformation of the eastern Corinth rift (Greece) is distributed along several E‐W trending active normal faults. Here the 25‐km‐long Pisia fault experienced up to 150 cm of coseismic displacement during the 1981 Alkyonides earthquake sequence ( M = 6.7, 6.4, 6.3). Using terrestrial laser scanning, coupled with analyses of color changes, lichen colonization, and karstic features, we identify differentially weathered horizontal stripes on the exposed Pisia fault plane. The stripe boundaries occur at scarp heights of 1.10, 2.05, 2.85, 3.60, 4.15, and 5.15 m, with two additional possible boundaries at 3.10 and 4.65 m (~±0.1 m, respectively). This indicates that six to eight paleoearthquakes have exhumed the fault plane in a series of distinct coseismic slip events. A vertical profile of cosmogenic 36 Cl measurements is used to constrain age models of the exhumation. The results imply that, in addition to the last earthquake of 1981 (EQ1), exhumation events occurred at ~2.0 kyr (EQ2), ~3.1 kyr (EQ3), ~4.5 kyr (EQ4/4a,b), ~6.0 kyr (EQ5), and ~7.3 kyr (EQ6/6a,b), with modeled age uncertainties of ~0.7 kyr. Bayesian modeling provides a middle and late Holocene slip rate of 0.5–0.6 mm/yr (last 7.3 ± 0.7 kyr), while the upper part of the 8.45‐m‐high fault plane was exhumed at a higher rate of 0.8–2.3 mm/yr (7.3 ± 0.7 kyr to 10.2 ± 1.9 kyr). This slip rate variability suggests an increased seismicity or larger slip events during the early Holocene.