Currency Chaos & Oil...

Oil is undergoing a big selloff after failing at the $50 level.  It is trading down about two dollars around $48.  Is this due to the weakness in the British Pound that is resulting from the Brit-ex vote that causes strength in the US Dollar which in turn causes Oil to be weak because it is priced in dollars?   Huh?  Did the chicken come before the egg?  Beats me...I certainly don't claim to be smart enough to comprehend all these various dynamics.  But it does seem like a weird coincidence that this is happening right at the nice round $50 level.