Field reconnaissance and observations from the February 6, 2023, Turkey earthquake sequence

On February 6, 2023, a sequence of earthquakes hit Kahramanmaras, Turkey, with magnitudes of Mw = 7.8 and 7.5, at 4:17 am and 1:24 pm local time, respectively. According to the records, the Mw = 7.8 event was the biggest earthquake since the 1939 Erzincan earthquake of the same magnitude and second-strongest recorded after the 1668 North Anatolia Earthquake. However, it was the most devastating earthquake in the history of Turkey in terms of structural and geotechnical damage and fatalities caused by this. The objective of this article is to explore the aftermath of this major seismic event, with a particular focus on the following areas: (1) regional geology and seismotectonics background, along with geological field observations; (2) seismological context and analysis of strong ground motion records; (3) a summary of field reconnaissance findings; (4) an evaluation of residential structures, bridges, schools, hospitals, and places of worship, as well as, building foundations; (5) a study of soil and rock slopes, seismic soil liquefaction manifestations, rockfalls, earth dams, harbors, lifelines, ports, deep excavations, and retaining structures. The conclusions drawn herein are from the field reconnaissance and, therefore, are preliminary in nature. Subsequent research utilizing the gathered data will offer more comprehensive insights and definitive conclusions regarding the observations discussed.