Holocene tephrochronology of Kerguelen Archipelago , 1 Subantarctic Indian Ocean 2 3

31 Up to now, no geochemical or geochronological data has been published about Holocene 32 volcanic activity on the Kerguelen Archipelago. Here we present the first continuous 33 Holocene chronology of volcanic eruptions on the archipelago. We compared 34 sedimentological, geochronological and geochemical data from two lake sediment cores taken 35 in two different depocenters of Lake Armor, located ca. 70 km away from the archipelago’s 36 main volcanic area. This allowed us to confidently assign the pumiceand ash-rich layers that 37 are interbedded in the lake sediments to distinct volcanic eruptions. Eight main and 3 minor 38 eruptions were thus documented and dated, among which the youngest occurred during the 39 Middle Ages, in AD 1020 +/58. The oldest eruption (11,175 +/275 cal. BP) is also by far 40 the strongest and deposited, more than 1.2 m of up to 3 cm-large pumices in Lake Armor area. 41 The new tephrostratigraphy presented here may serve as a tool to synchronise 42 paleoenvironmental records from Kerguelen as well as marine records from he Kerguelen rise 43 and beyond. areas. 44