Abstract:

This dataset reports CTD and water column profiles near the GC-600 natural oil seep in the Gulf of Mexico aboard R/V Point Sur cruise PS19_14 in the Gulf of Mexico from 2019-01-26 to 2019-01-28. Water column profiles were collected at two sampling sites (GC-699, and GC-600) and the data include CTD, dissolved oxygen, Chlorophyll-a Dissolved Organic Matter (DOM) fluorescence (fDOM), altimeter, Photosynthetically Available Radiation (PAR) and Surficial PAR (SPAR). During this cruise, we performed a series of CTD casts in and around both sites to constrain water column structure and radium isotopes. The main objective of the cruise was to use the ROV Odysseus from Pelagic Research Services to directly sample hydrocarbons emanating from MegaPlume at GC-600 (27° 22.199'N 90° 34.262'W). During our time at sea, we further aimed to sample radium isotopes in the water column profiles. The R/V Point Sur cruise PS19_14 was led by chief scientist Dr. Richard Peterson.

Suggested Citation:

Richard Peterson. 2019. CTD and water column profiles collected aboard R/V Point Sur cruise PS19_14 in the Gulf of Mexico from 2019-01-26 to 2019-01-28. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-wp6x-2736

Purpose:

Data were collected to constrain the water column structure at and around the GC-600 natural oil seep.

Data Parameters and Units:

Time, Latitude and longitude (decimal degrees), temperature (degrees C), conductivity (mS/cm), pressure (db), chlorophyll-a fluorescence (mg/m^3), Color Dissolved Organic Matter fluorescence (CDOM; mg/m^3), altimeter (m), dissolved oxygen concentration (mg/l), Photosynthetically Available Radiation (PAR; micromol m^-2 s^-1) and Surficial PAR (SPAR; micromol m^-2 s^-1), flags. Dataset includes cruise documentation and cruise report.

Methods:

Sampling stations and nomenclature: During this cruise, two separate sampling sites were visited. The first site, GC-699 (numbered site 001 throughout data set), is considered a control site for the primary sampling site, GC-600 (numbered site 002 throughout data set). The site GC-699 is located ~53 km to the ESE of GC-600. The event code nomenclature is to sequentially number each cruise activity in which a sampling device goes over the side. A number code was used where the first three numbers (e.g., 001) refer to the site name and are separated from the sampling activity code (e.g., 01, 02) by a period. So, for example, an event code of 001.01 would represent the first sampling activity at site 001, whereas 002.13 would represent the 13th sampling activity at site 002. The four CTD casts were conducted first at GC-699 to collect enough surface (1 m) and deep (1100 m) water to use as inoculant waters for our oil incubations that would follow the cruise. These water samples were subsequently particle filtered (through GF/F filters) and made Ra-free (via filtration through Mn fibers). Then, at GC-600 three CTD casts were conducted. More details on these CTD casts and cruise activities is available in the cruise report (Preliminary Cruise Report_PS19_14.pdf) included with this dataset.

Instruments:

Sea-Bird SBE 9, WET Labs ECO-AFL/FL, WET Labs CDOM, SBE 43, Biospherical/Licor.

Individual Files: