About Afar Dallol Drilling - ONset of sedimentary processes in an active rift basin (ADD-ON)

Since the early days of the continental drift theory, the Afar triangle has been an ideal field laboratory where the onset of continental and potentially future oceanic rifting can be studied on land with easy access. The Danakil Depression is the northern portion of Afar where the Red Sea rift propagate on land, and is characterized by active rifting and recent volcanism.

The ADD-ON project (Afar Dallol Drilling) aims to explore drilling targets in the Danakil Depression (Afar, Ethiopia). The overarching scientific goal is to get insights into the detailed sedimentary facies evolution in an active rift setting paced by global environmental fluctuations and their interplay with volcano-tectonic events. Seismo-stratigraphic interpretations based on industrial seismic sections, core and borehole data evidence the presence of Pleistocene evaporite units until the depth of about 900 m below the Dallol salt pan (central Danakal Depression, northern Afar). However, to date no sub-salt sedimentary core records are available from the central part of the rift basin filled with more than 2 km of sediments.

The ICDP have approved our proposal. We aim to drill to ~2.3 km into the evaporite basin just south of Dallol volcano in Danakil basin in order to understand:

(1) intermittent and incipient basin dynamics in an initial extensive continental rift basin: from rifting towards the development of passive margins,

(2) East African climatic changes and Hominin evolution,

(3) the limits of the deep biosphere in extreme hypersaline and high-temperature environments below the salt deposits,

(4) natural fluid flow in an active geothermal system,

(5) earthquake activity and volcanic events in remote areas.

Deep scientific drilling in the Afar will be necessary in the rapid assessment of geothermal potential, the quest for ground water resources and advanced Potash exploitation.

The ADD-ON on study area is in the Danakil Depression of Northern Afar, and the aims is to drill more than 2 km into the evaporite basin (figures modified from Foubert et al. (2024) in Scientific Drilling - https://sd.copernicus.org/articles/33/207/2024/ )