Multi-proxy analysis of sediment cores from Lake Ginjal (Azores archipelago, Portugal)

The Azores archipelago is a group of nine oceanic volcanic islands located in the mid-North Atlantic, roughly 1500 km from Europe and 1900 km from America. In 2018, a sediment core was recovered from Lake Ginjal on Terceira island. A 3.5 m long sediment core was taken using a Russian chamber corer, 0.5 m long, with 5 cm diameter. Lake Ginjal occupies the bottom of a small crater at 390 m above sea level located in the plains of Achada, the oldest volcanic crater of Terceira island. Its maximum length and width are 120 m and 70 m, respectively, and its maximum water depth is 1 m. The core was dated using ¹⁴C and produced a multi-proxy dataset of geochemical and biological analyses that we used to uncover paleoenvironmental changes on Lake Azul in the last 550 years.