UNCW and ECU conduct baseline cruise
On Saturday, May 22, 2010, a research team, comprised of researchers, research technicians, and students from UNCW and ECU participated in a cruise to gather baseline data on hydrocarbon levels in the Gulf Stream off the coast of North Carolina. The research team collected water samples at surface and depth at each of 5 stations (1, 25, 60, 80, and 100 miles off of Wilmington) and sediment samples were collected at the inshore stations (0 and 25 miles). Water from each station was separated into particulate and dissolved phases onboard the vessel using glass fiber filters is being analyzed by Dr. Mitra (ECU). Material trapped on the filters is defined as the particulate phase and material that passes through the filter is referred to as the dissolved phase. The particulate and dissolved phases will be analyzed for total organic carbon.
If petroleum is present in the water, then excessively high levels of total organic carbon are expected in the partriculate and dissolved phases. Sediment samples are also being analyzed by Dr. Mitra and additional sediment samples will be analyzed at UNCW/CMS for microbial activity by Dr. Jeff Wright (UNCW). Basic physical parameters (water temp, salinity, dissolved oxygen, and pH) were characterized using a CTD. A CDOM fluorometer, which can be used to detect petroleum presence, was also integrated into the CTD system for in situ measurements.
Taken together, our combined analyses are robust enough to be able to ascertain the amount of source of any hydrocarbons found in the background samples analyzed. Should oil from the Deepwater Horizon ultimately enter the Gulf Stream, these baseline samples will be instrumental in identifying the extent to which materials derived from the Deepwater Horizon plume are impacting coastal waters off of the NC coast.
Hydrocarbon concentrations in selected samples from this and future cruises will be compared to their concentrations and ratios in source oil isolated from the Deepwater Horizon spill by scientists at the USGS in Menlo Park.