Geophysical constraints on the crust and upper-mantle structure of Greenland (UPPA-GL)

Scientists working on this geophysical study of the crust and upper mantle of Greenland aim to characterize the seismic velocity structure of Greenland's crust and upper mantle in three dimensions; and to integrate these results with gravity and heat-flow data, laboratory estimates of material properties, and petrological data to map variations in temperature, composition, and heat flux. Researchers will use seismic data from the NSF- and internationally funded GLISN seismic network, supplemented by targeted collection of data at a limited number of temporary PASSCAL stations. Field work begins in the summer of 2014, continues in 2015, and ends in 2016. In 2014 a field team of 3 will deploy seven seismic stations (provided by PASSCAL), six located on the northern ice sheet and one on the East Greenland coast. The power system consists of solar panels and rechargeable batteries in a large Hardigg case attached to the seismic sensor, which sits in a small barrel. The team also will deploy GPS stations at two of the sites with a similar power system and overall setup. The stations will be serviced in summer 2015, and retrieved and returned to the US in summer 2016. The team will travel to Greenland in June 2014 using the ANG logistics chain, and base at Summit Station to deploy the inland sites. At Summit, the field team will test the seismic systems first, building them into fully functional systems before breaking them down and packing them for transport via Twin Otter to the installation sites. The team will make day trips to the installation sites, returning to Summit each day. When this work is complete, the researchers will depart with the Twin Otter and fly to Akureyri. Approximately two weeks later, the field team will return to Kulusuk to install their final site in SE Greenland. The team will fly commercially to Kulusuk and test equipment shipped there earlier in the season. The Norland Air Twin Otter will then pick up the team and cargo in Kulusuk and fly to Kagssortoq where the researchers will install the final station. They will spend one night in the field, and return to Kulusuk. The Twin Otter will return to Akureyri, and the researchers will depart Greenland or continue on education-and-outreach work related to this grant but not requiring logistics support. In 2015 the team will again use the ANG logistics chain and base at Summit to deploy to the northern sites for maintenance visits. A Norland Air Twin Otter will fly from Akureyri, Iceland to Summit to work with the team. They will take day trips to the installation sites, returning to Summit each day, except for one when they will overnight at either Danmarkshavn or EGRIP. When this work is complete, the researchers will depart with the Twin Otter and fly to Akureyri. After one day in town, the field team will fly via Twin Otter to their final site in SE Greenland at Kagssortoq (SE1), where they will swap the data-logger and make some improvements at the site. They will spend one night in the field, and return with the Twin Otter to Akureyri. In 2016, four researchers will return to Greenland, flying via ANG to Kangerlussuaq, and then putting in via LC-130 to a newly established deep drill site north of Summit Station called EGRIP (East GReenland Icecore Project, managed by the Centre of Ice and Climate, University of Copenhagen). The team will base at EGRIP and visit their seismic sites via Twin Otter to dig out, dismantle, and remove all project equipment and batteries for retrograde to EGRIP. Each site will require two flights due to weight. When the work is completed, a total estimate of 7000 lbs. of equipment and batteries will be retrieved by LC-130 and returned to Kangerlussuaq during the late June flight period. Meanwhile, the Nettles team will return to Akureyri via the Twin Otter and stay for two nights. Three team members will then return to Greenland to pull out the Kagssortoq site (SE1) in the southeast, an effort involving one overnight in the village. When this work is done, the researchers will return to Akureyri for onward travel to the US.

CPS will provide Air National Guard (ANG) coordination for passengers and cargo, user days in Kangerlussuaq and EGRIP, freight to/from EGRIP and from Kulusuk to Kangerlussuaq, fixed wing charters, accommodation in Kulusuk, and camp and safety equipment. PASSCAL will provide tools and assistance with field support. UNAVCO will provide GPS units. All other logistics will be organized by the researcher and paid through the grant.