There has been a bit of discussion lately on the interpretation of the "Silverpit" structure in the Southern North Sea.
A couple of years ago a paper was published in Nature about a circular set of faults surrounding a sub-surface depression in the top-Cretaceous reflector. The interpretation was that this was an impact structure. A summary of the paper can be found at the Geological Society website (if you're really interested, I can email you the paper). Well, there have been alternative interpretations published over the last few months, re-interpreting it as a sagging structure caused by withdrawl of Zechstein salt at depth. John Underhill (of Edinburgh University) has presented data orthogonal to the original section (link above), which does put a very different interpretation on the structure.
It still doesn't look right though - the "central peak" structure in the original paper is still a very anomalous structure, and Underhill's interpretation of thickness variations in the overburden to the salt is inconsistent - the Cretaceous thins in one direction and the Jurassic in another, combining to give the appearence of synsedimentary halokinesis. It still looks odd to me.
I am very surprised at a seismologist of Phil Allen's experience not looking out-of-plane though.
(In other comments since I first wrote this, Mr Allen claims he did, but disagrees with Underhill's interpretation.)
Somewhere to write my notes and comments while out and about. Typically, these are bits of science news that tickle my fancy.
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