Although the final stage of formation of the Gulf of Mexico is fairly well constrained, earlier evolution is still debated. The final stage was rotation of Yucatan about a Florida Straits Euler pole that created most of the observed oceanic crust (Pindell and Dewey, 1982). From observations of salt overlying seaward-dipping reflectors (diagnostic of volcanism during the rift to drift transition) in the northeast Gulf of Mexico, we suggest that salt was deposited at the onset of sea floor spreading, which coincides with initiation of the rotational motion of Yucatan. It is important to understand Yucatan...