Shark's pectoral fins are angled like that. Also, if it were meant to be an Orca, there should be some white markings within the body of the animal. The flukes could be construed as being horizontal (more like an orca) rather than vertical (like a shark). However, I will just blame this on perspective, once again.
Remember, the "white" is light blue. So it may have blended in over time or its to close to tell?