Paleoclimate records from the Atacama Desert are rare and mostly discontinuous, mainly recording runoff from the Precordillera to the east, rather than local precipitation. Until now, paleoclimate records have not been reported from the hyperarid core of the Atacama Desert (<2 mm/yr). Here we report the results from multi-disciplinary investigation of a 6.2 m drill core retrieved from an endorheic basin within the Coastal Cordillera. The record spans the last 215 ka and indicates that the long-term hyperarid climate in the Central Atacama witnessed small but significant changes in precipitation since the penultimate interglacial. Somewhat ‘wetter’ climate with enhanced erosion and transport of material into the investigated basin, commenced during interglacial times (MIS 7, MIS 5), whereas during glacial times (MIS 6, MIS 4–1) sediment transport into the catchment was reduced or even absent. Pelagic diatom assemblages even suggest the existence of ephemeral lakes in the basin. The reconstructed wetter phases are asynchronous with wet phases in the Altiplano but synchronous with increased sea-surface temperatures off the coasts of Chile and Peru, i.e. resembling modern El Niño-like conditions.

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.The most frequently applied technique for earthquake analysis on limestone bedrock fault scarps is exposure dating using cosmogenic 36 Cl (e.g., Zreda & Noller, 1998). A regular and dense distribution of 36 Cl samples can MECHERNICH ET AL. 4266

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 m, 2.05 m, 2.85 m, 3.60 m, 4.15 m, and 5.15 m, with two additional possible boundaries at 3.10 m and 4.65 m (ca. ± 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 36Cl 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 mid 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.

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