IODP Expedition 339

IODP Expedition 339
Name	Expedition 339
Program	Integrated Ocean Drilling Program
Ship	RV JOIDES Resolution
Dates	2012
Objectives	Study Arctic paleoceanography, glaciation, methane hydrates
Sites	Arctic Ocean, Lomonosov Ridge, Yermak Plateau
Outcome	New records of Middle Miocene to Pleistocene climate, gas hydrate insights

IODP Expedition 339

IODP Expedition 339 was an ocean drilling campaign conducted by the Integrated Ocean Drilling Program aboard the RV JOIDES Resolution to recover sediment and stratigraphic records from the Arctic Ocean. The expedition sought to test hypotheses about Cenozoic climate evolution, Arctic glaciation, methane hydrate stability, and tectonic history using coordinated coring, logging, and paleoenvironmental analyses. Scientific aims connected paleoclimatology, paleoceanography, and sedimentology to address questions relevant to the Paleogene, Neogene, and Quaternary intervals.

Background and Objectives

The expedition built on work by programs such as the Ocean Drilling Program, Deep Sea Drilling Project, and subsequent scientific initiatives including the International Ocean Discovery Program and Arctic programs led by institutions like the University of Washington, University of Oslo, and Alfred Wegener Institute. Objectives included testing models of Arctic gateway evolution linked to the opening of the Fram Strait, examining the onset of Northern Hemisphere glaciation associated with the Pliocene and Pleistocene, and constraining methane hydrate occurrence tied to Neogene sedimentation rates and heat flow anomalies. Investigators referenced paleoclimate reconstructions, plate reconstructions from the North Atlantic plate tectonic framework, and stratigraphic correlations to explore links among the Greenland Ice Sheet, Antarctic cryosphere developments, and global climate events such as the Mid-Pliocene Warm Period and Miocene Climate Optimum.

Expedition Ship and Personnel

The RV JOIDES Resolution served as the primary platform, with operational support from shipboard facilities comparable to those used in previous expeditions such as ODP Leg 151 and IODP Expedition 302. The scientific party combined specialists affiliated with institutions including the British Geological Survey, Lamont‑Doherty Earth Observatory, University of Bergen, University of California, Scripps Institution of Oceanography, Woods Hole Oceanographic Institution, and GEOMAR Helmholtz Centre. Leadership roles included an Expedition Project Manager, Co-Chief Scientists with expertise in micropaleontology and geochemistry, and onboard technicians trained in geotechnical logging, well logging by Schlumberger-like teams, and downhole logging tools. Collaborating agencies included the National Science Foundation, European Consortium for Ocean Research Drilling, and national polar research programs.

Drilling Sites and Operations

Drilling targeted loci on rises and ridges such as the Lomonosov Ridge, Yermak Plateau, and adjacent basins with sites selected via multibeam bathymetry, seismic reflection profiles from institutions like the U.S. Geological Survey and the Norwegian Polar Institute, and legacy piston core records from the International Arctic Research Center. Operations used advanced piston coring, extended core barrel coring, and rotary coring systems adapted for high-latitude ice conditions. The campaign navigated hazards documented in seismic hazard assessments, and coordinated with icebreaker escorts when encountering sea ice near Svalbard and the Greenland continental margin. Shipboard stratigraphic logging integrated core description, magnetic susceptibility, and color reflectance to correlate sections among sites.

Scientific Methods and Sampling

Sampling approaches combined micropaleontological analysis of foraminifera and diatoms, stable isotope geochemistry of oxygen and carbon isotopes, X‑ray fluorescence core scanning, grain size analysis, and paleomagnetic stratigraphy to establish age models tied to magnetostratigraphy and biostratigraphy. Methane and gas hydrate investigations used pore‑water geochemistry, headspace gas analysis, and pressure coring techniques comparable to HYACINTH-like approaches to assess hydrate concentration. Paleoproductivity proxies such as biogenic silica, organic carbon TOC measurements, and biomarker lipid analyses (including alkenones and GDGTs) were employed alongside seismic stratigraphy and downhole logging to infer past oceanography and circulation changes, including Atlantic Water inflow variability and sea‑ice extent.

Key Findings and Results

Results provided new constraints on timing and development of Arctic glaciation, indicating episodes of ice‑rafting and increased detrital inputs during the late Miocene to Pleistocene that refine earlier syntheses of Northern Hemisphere glaciation onset. Paleoceanographic reconstructions revealed shifts in Atlantic gateway circulation modulated by tectonic changes along the Eurasian Basin and Fram Strait, with implications for global heat transport models and paleoclimate simulations used by groups such as the Paleoclimate Modelling Intercomparison Project. Geochemical signatures highlighted intervals of enhanced organic matter deposition and methane release episodes, informing assessments of methane hydrate stability in response to Pliocene warming events and modern anthropogenic forcing scenarios evaluated by the Intergovernmental Panel on Climate Change. Biostratigraphic and magnetostratigraphic frameworks improved correlation across Arctic sediment cores and boreholes used by stratigraphers and sedimentologists.

Environmental and Safety Considerations

Expedition operations conformed to Polar Code guidelines and risk assessments similar to those employed by polar research programs and maritime safety authorities, addressing sea‑ice hazards, hydrocarbon seep detection, and potential disturbance of gas hydrates. Environmental monitoring included mitigation of discharged cuttings, handling of hydrocarbon‑bearing cores, and coordination with national environmental agencies to minimize impacts on Arctic ecosystems monitored by the Norwegian Institute for Nature Research and other conservation bodies. Health and safety plans covered cold‑weather operations, emergency medical support, and contingency coordination with icebreaker assets and search and rescue services operating in high‑latitude waters.

Legacy and Impact on Earth Sciences

The expedition left a legacy through data contributions to international databases used by researchers in paleoclimatology, paleoceanography, and geodynamics, influencing studies at Lamont‑Doherty, Alfred Wegener Institute, and the British Antarctic Survey. Results have been integrated into multidisciplinary syntheses concerning Arctic gateway evolution, methane cycle dynamics, and ice‑sheet history, informing subsequent proposals to drilling programs and climate model intercomparison projects. The expedition enhanced methodological protocols for high‑latitude coring, fostered international collaborations among polar institutions, and provided long‑term archives for museums and core repositories that continue to support research into Cenozoic climate change and Arctic system science.

Category:Ocean drilling expeditions