Kahramanmaras Afterslip 2023-2024, East Anatolian Fault, Turkey

Fourteen carbon-rod extensometers (creepmeters) were placed across surface ruptures of the Mw7.8 and Mw7.6 ruptures of the Kahramanmaraş earthquake sequence of 6 February 2023 to record potential afterslip. The data are organized in site folders. Each folder contains a graphical time series (pdf) and narrative of installation and location information. Data from 2023 and 2024 are listed as .csv text files and Igor.pxp files. Each instrument consists of a carbon rod extensometer with a rotary Hall sensor, which has a full-scale wrap of ≈10 mm measured to 12-bit-precision (~2.5 µm), and a concatenated range of 1.6 m (after the data are unwrapped). Most of the data were recorded at a rate of 1 sample per minute, but some data are recorded at rates as low as 10 minute samples. At two sites (Karakose and Goksun (1Dec2023) biaxial creepmeters were installed, the orthogonal component permitting fault dilation to be quantified.
At many sites where coseismic offsets exceeded 3 m, afterslip was absent and measured displacements recorded fissure closure and collapse. At three locations, however, afterslip occurs at 3-5 mm/yr. These are the two ends of the Mw7.6 event and at the eastern end of the Mw7.8 event in the Puturge creeping section. The 2020 Sivrice earthquake also terminated in the Puturge creeping segment.