Recent sediments and sedimentological processes in the Strait of Magellan

The Strait of Magellan is made up of 5 main morphological-sedimentological units: 3 are located in the Atlantic arm and two in the Pacific. The first unit consists of the first two basins that open onto the Atlantic Ocean and that are separated by a narrow (Primera Angostura) and by the northernmost tip of Punta Arenas Basin. The second morphological-sedimentological unit basically consists of the Punta Arenas Basin, which follows the first two basins through as additional narrow (Segunda Angostura). This is the largest basin and has a depth of 400-500 m. The energy levels, which tend to decrease gradually from the north to the south, affect the distribution of sands become finer. Starting from the Punta Arenas Basin, a network of bays and channels branch off forming the third physiographical unit which is characterized by both ancient tillite deposits and fluvio-glacial mud. The Pacific arm is characterized by two narrow, prolonged basins (fourth and fifth unit). These basins are the ...