Site U1604

Site U1604 (proposed Site MB-02C) was cored on the lower slope below the Melville Bugt Trough Mouth Fan (TMF) at 1943 meters below sea level (mbsl) at 73°06.9077′N, 63°47.3996′W below a prominent crescent-shaped protrusion of the Melville Bugt TMF on the northwest Greenland shelf margin (Figure F1). The site was aimed at retrieving a continuous high-resolution record of ice sheet–ocean interactions and processes going back to early Pleistocene. The depth target was the base of an expanded drift channel succession situated on the lower slope between two paleo–ice sheet outlets representing major drainage routes for the northern Greenland ice sheet (NGrIS) into Baffin Bay (Knutz et al., 2019; Newton et al., 2017, 2020, 2021). The sedimentary succession is covered by regional 2D industry data as well as high-resolution multichannel seismic data providing a detailed seismic stratigraphy to guide the drilling objectives (Figure F2). The strategy at Site U1604 was to core through the youngest seismic units (9–11) to capture the expanded depositional sequence within Seismic Unit 8 showing stratified intervals with asymmetric geometries resembling contourite drifts. Site U1604 is paired seismic-stratigraphically with Site U1603, located 16 nmi (~30 km) to the southeast adjacent to a deepwater channel. With Horizon 7 as a stratigraphic target (about 420 meters below seafloor [mbsf]), the succession cored at Site U1604 is complementary to Site U1603 but records sedimentation that is more distal to the channel system and presumably recovers an interval older than at Site U1603.