Arc rifting, metallogeny and microplate evolution: An integrated geodynamic, magmatic and hydrothermal study of the Bismarck Archipelago, Papua New Guinea, Cruise No. SO299, DYNAMET, 6 JUNE - 29 JULY 2023, Townsville (Australia) - Singapore

Cruise SO299 DYNAMET from Townsville (Australia) to Singapore aimed at studying the links between geodynamics (regional-scale plate tectonics, local structural geology and volcanism) and metallogeny with a special emphasis on the Au-rich mineralisation on and in the vicinity of Lihir Island, Papua New Guinea. The research programme started on 13th June and ended on 15 th July 2023, totalling to 32.5 working days within the Exclusive Economic Zone of Papua New Guinea and international waters. Underway hydroacoustic and gravity data were additionally recorded in international waters during the transit towards Singapore. The three main working areas targeted the New Ireland Basin at the newly discovered Karambusel vent field (Conical Seamount) and Mussel Cliff, the Weitin Fault area south of New Ireland, and the Mussau Ridge. We performed >4,800 kilometers of hydroacoustic (multibeam echosounder and sub-bottom profiler) and gravimetric surveys, twelve dives with the remotely operated vehicle (ROV) KIEL 6000 from GEOMAR, 16 stations with the TV-guided grab, 20 chain bag dredge and 20 heat flow stations. We recovered a total of 447 rock and 346 sediment samples and took 570 individual gas and fluid samples. We deployed and recovered 18 ocean bottom seismometers (OBS) and 16 ocean bottom magneto-telluric (OBMT) instruments in the vicinity of Lihir island. The wealth of samples and data collected during the cruise and complemented by a variety of geophysical, petrological and geochemical analyses post-cruise will aid the development of a new spatial and temporal model of the magmatic and hydrothermal evolution in response to recent plate tectonic changes.