Chemical analysis and physical properties of weathered, unweathered, and surrogate crude oils from the Deepwater Horizon accident in the Gulf of Mexico, July 2010 to January 2011

Gulf of Mexico (GOM) researchers have been interested in the physical properties and chemical characterization of the Mississippi Canyon lease block 252 (MC-252) oil and have requested aliquots of this oil from BP in order to determine these characteristics. Since quantities of this oil are limited, BP has prepared this report to provide researchers with a detailed description of the oil’s physical and chemical characteristics so that they do not have to replicate experimental analyses that have already been conducted on the various MC-252 reference oils. Data included with this report relate to unweathered MC-252 oil collected from the Oil Barge Massachusetts (Massachusetts) on August 15, 2010; two distinct weathered oils collected by skimmers from the GOM in July 2010 as part of the Response to the Deepwater Horizon (DWH) accident; and a surrogate oil collected from the GOM Dorado Field, Marlin Platform, which has characteristics similar to MC-252 oil. In addition, data for MC-252 oil collected on June 19, 2010, from the Q4000 Well Intervention vessel is also available as a separate data set (Reference No. O-01v01). This dataset includes data associated with the following oils: - Unweathered oil—MC-252 oil collected from the barge Massachusetts on August 15, 2010 - Weathered oils skimmed from the GOM as part of the Response to the DWH accident - Oil collected from the U.S. Coast Guard Cutter Juniper (Juniper) on July 19, 2010 - Oil collected from Barge No. CTC02404 on July 29, 2010 - Surrogate oil—Oil collected from the Dorado Field, Marlin Platform in November 2011, which has properties similar to MC-252 oil. The chemical and physical parameters provided in this data posting include:  Parent and alkylated polycyclic aromatic hydrocarbons (PAHs)  Saturated hydrocarbons (SHCs)  Total extractable matter (TEM) and diesel range organics (DRO)  Benzene, toluene, ethyl benzene, and xylenes (BTEX) and other volatile hydrocarbons classified as paraffins, isoparaffins, aromatics, naphthenes, and olefins (PIANO)  Geochemical biomarkers (steranes and triterpanes)  Dipropylene glycol n-butyl ether (DPnB, a dispersant component)  Metals  Carbon stable isotopes for whole oil and saturate, aromatic, resin, and asphaltene fractions  Additional crude oil chemistry parameters and analytes  Saturate, aromatic, resin and asphaltene of the C15+ fraction  Selected physical properties  Simulated distillation of crude oil. Three subsamples of each of the four reference oils were analyzed for this report. Laboratory triplicates were also performed on one of the subsamples for each reference oil for all of the organic chemistry analytes and for many of the physical property parameters (where sample volumes were sufficient). For the metals analyses, a laboratory duplicate was performed on one of the Massachusetts subsamples. When applicable, samples were analyzed according to the Gulf Coast Incident Management Team Quality Assurance Project Plan (GCIMT 2011). The data files also include an Excel file that contains average values for the chemical and physical data for each of the reference oil samples, along with general information and GC-FID chromatograms.