Night falls on the U.S. Coast Guard Cutter POLAR SEA. The POLAR SEA is a 399-ft long icebreaking vessel served as home for her crew and the MITAS expedition science team for 12 days in September 2009. - click on image to enlarge

Co-chief scientist Warren Wood (U.S. Naval Research Laboratory) and Pat Hart (U.S. Geological Survey) review seismic data to assist in selection of the next coring site. - click on image to enlarge

Lowered into the chilly Beaufort Sea is the CTD (Conductivity, Temperature, and Density). The CTD is attached to a metal frame called a rosette or carousel along with numerous water sampling bottles. Deployed off the side of the POLAR SEA, the CTD provided information about the composition of the water column. - click on image to enlarge

Co-chief scientist Jens Greinert (Royal Netherlands Institute for Sea Research) collects water samples from sampling bottles on the CTD rosette for further analysis.

The MCS, or Multi-Core Sampler, is lowered into the water for its trip down to the seafloor. The MCS used onboard the POLAR SEA collected four short cores simultaneously. Upon its return to the surface, the cores were removed and samples were collected for post-cruise microbiological and geochemical analyses. - click on image to enlarge

Tina Treude (IFM-Geomar) and Stefan Krause (IFM-Geomar) assist ENS Chris Verlinden (U.S. Coast Guard) in securing the MCS system upon its return to the ship. - click on image to enlarge

Shown here is the acoustic resonator apparatus (ARA) that utilized a core collected by the MCS system. This device allows researchers to extract the sound speed of the sediment which is used by geophyscists and other researchers to accurately interpret seismic survey data, and hence accurately locate gas bearing sediments and methane hydrate. Chad Greene (University of Texas - Austin) is shown using the ARA which utilizes an acoustic source and a receiver (hydrophone) attached to the top of the sample. A vector signal analyzer (VSA) provides an acoustic excitation signal, which sounds something like a bird's chirp. Excited in this way, the sample resonates like an organ pipe. The VSA also digitizes the acoustic data received on the hydrophone. This data is converted into a resonance spectrum which is used to infer the speed of sound in the sample material. Chad is measuring the temperature of the core with a thermistor, which is important because the sound speed is dependent upon temperature. - click on image to enlarge

Using a cable pulley system supported by the J-frame seen here, the piston corer is lowered into the water. The piston core system can collect cores up to 9 m in length, with the longest core collected during the MITAS expedition measuring a little more than 7 m in total length. - click on image to enlarge

Retrieving a piston core in the Arctic was made a little more interesting with the presence of icebergs. - click on image to enlarge

Chief Scientist Rick Coffin (U.S. Naval Research Laboratory), ENS Chris Verlinden (U.S. Coast Guard) and ENS Jenn Hom (U.S. Coast Guard) anxiously await the arrival of the piston core on deck. - click on image to enlarge

Upon the return of the piston corer to the back deck of the POLAR SEA, the coring team begins the process of removing the core liner from the piston. - click on image to enlarge

After its removal from the piston, the core liner was measured to determine the total length of recovered sediment and marked in preparation for cutting into meter-long sections. - click on image to enlarge

Once the core liner is cut into meter-long sections, sediment gas samples were collected by Leila Hamdan (U.S. Naval Research Laboratory) with assistance from Chad Greene (University of Texas – Austin). - click on image to enlarge

In addition to sediment gas subsamples, free gas samples were also collected from the core for further analysis by Tom Lorenson with the U. S. Geological Survey.

After all samples were collected and measurements made outside in the core processing area, the core sections where then carried inside to the Geo Lab. There the sections were scanned and readings regarding physical properties of the sediment (like electrical resistivity and magnetic susceptibility) were made using the Multi-Sensor Core Logger (MCSL) operated by Allen Reed (U.S. Naval Research Laboratory). - click on image to enlarge

After the MSCL scans were complete, Randy Larsen (St. Mary’s College) and Joe Smith (U.S. Naval Research Laboratory) split the core sections into a working half and an archive half using the GEOTEK core splitting system. - click on image to enlarge

Porewater found in the sediment of the archive half seen here was collected using Rhizon samplers. Co-chief scientist Kelly Rose (National Energy Technology Laboratory) and Joel Johnson (University of New Hampshire) conducted visual examinations of the core, noting the geology, lithostratigraphy, and sediment features of the core. - click on image to enlarge

Water samples wait for analysis in the Geochem Lab. - click on image to enlarge

Stefan Krause (IFM-Geomar) and Sunita Shah (U.S. Naval Research Laboratory) collect samples from the working half of the core section. The collection of sediment samples from the working half allow researchers the opportunity to learn more about features observed in the archive half. - click on image to enlarge

Sediment samples ready for further analysis to determine mineral composition and grain size. - click on image to enlarge

Much to the delight of the science team an adolescent walrus stopped by for a short visit one afternoon. - click on image to enlarge

The Aurora Borealis or Northern Lights as viewed from the helo deck onboard the POLAR SEA. - click on image to enlarge

An aerial view of the Barrow, Alaska and the Beaufort Sea - click on image to enlarge

The 2009 MITAS expedition science team - click on image to enlarge