As Brad mentioned previously, things are settling in a bit in many ways (mostly in our work/eat/sleep routine), but we're also coming upon some interesting geomorphology: Inactive spreading ridges. At the moment, we're transiting between the Rosanna and Rosa ridges - two in a system of seven en-echelon ridge/transform zones off the coast of Baja California Sur. We are, as I write, recording the magnetic field associated with the oceanic crust, which, when combined with precise laboratory dating of rock specimens, tells us about the history of such ridges. Previous studies have found that these ridges were active producing new oceanic crust from approximately 12 to 6 million years ago, and are interpreted as excellent evidence of microplate capture, a theory which helps explain, for example, the development of the San Andreas fault hundreds of kilometers away.
Andy
No comments:
Post a Comment