The explosion of the Deepwater Horizon oil rig in April 2012 resulted in the release of ~5 million barrels of crude oil into the Gulf of Mexico ecosystem, a fraction of which washed ashore onto Gulf beaches. We compare the detailed molecular analysis of hydrocarbons in oiled sands from Pensacola Beach to the Macondo wellhead oil (MWO) by Fourier transform ion cyclotron resonance mass spectrometry to identify major environmental transformation products of polar, high molecular weight petrogenic material from Pensacola Beach.