Andrea,
The 0.5 cm/yr number I quoted was from an unpublished analysis I had done, but there are published cross sections from which you can calculate similar numbers. The recently published The Salt Mine (AAPG Memoir 99), by Hudec and Jackson, has an interpreted seismic section on page 7 which shows 11 miles of advance on the Sigsbee Escarpment near Saint Malo, based on subsalt cutoffs, since the Miocene/Pliocene boundary (~5 Ma). Doing the quick math on the back of an envelope (check me Frank!) I get about 3.5 mm/yr of advance. If you are looking for a published reference, that may be about as good as I can come up with on short notice. I invite anyone to chime in if they have other published salt advance rates to share, from the GOM or elsewhere.
Scot Krueger
-----Original Message-----
From: Tectonics & structural geology discussion list [mailto:[log in to unmask]] On Behalf Of Andrea Billi
Sent: Thursday, January 12, 2012 9:32 AM
To: [log in to unmask]
Subject: Re: help - velocity of salt tectonics
Ijaz, Scot,
thanks a lot for your help.
Scot,
is there a publication reporting the data you mentioned?
thanks
Andrea
"Krueger, Scot" <[log in to unmask]> ha scritto:
> A good example of the rapid end of the spectrum would be the salt
> "surge" of the Sigsbee salt glacier in the central deepwater Gulf of
> Mexico, which has advanced by up to 25 km in the last 5 Ma, or an
> average geologic rate of 2.5 cm/yr. The rates in the GOM for an
> average location and an average time would almost always be below that
> rate. And since the local behavior at the front appears to be
> stick-slip over periods of a few million years, the shorter term slip
> rate during the slipping phase may be somewhat higher. Hope this
> helps.
>
> Scot Krueger
>
> -----Original Message-----
> From: Tectonics & structural geology discussion list
> [mailto:[log in to unmask]] On Behalf Of Andrea Billi
> Sent: Wednesday, January 11, 2012 5:09 AM
> To: [log in to unmask]
> Subject: help - velocity of salt tectonics
>
> Dear All,
>
> I was looking for typical ranges of velocities for sedimentary
> overburdens sliding over a salt layer along passive margins.
>
> In models by Gemmer et alii (Basin Research 2004, 16, 199-218) and
> Albertz et alii (Tectonics 2010, 29, TC4017,
> doi:10.1029/2009TC002539) I see velocities between a few millimetres
> to a few centimeters per year, depending on various boundary
> conditions.
>
> Do you know other natural or experimental data concerning these velocities?
>
> Thanks a lot
>
> Andrea
>
> _________________________________________________
> Andrea Billi (PhD)
> Consiglio Nazionale delle Ricerche, IGAG, c.o. Dipartimento Scienze
> della Terra, Sapienza Università di Roma, P.le A. Moro 5, 00185, Rome,
> Italy.
>
> Phone: +39 06-49914955
> Skype: a.billi
> Email: [log in to unmask]
> Web site: http://www.andreabilli.com
> _________________________________________________
>
> Dalla Costituzione della Repubblica Italiana Art. 9: "La Repubblica
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> Art. 33: "L'arte e la scienza sono libere e libero ne è l'insegnamento."
>
> "Non è grave il clamore chiassoso dei violenti, bensì il silenzio
> spaventoso delle persone oneste." Martin Luther King
>
>
>
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_________________________________________________
Andrea Billi (PhD)
Consiglio Nazionale delle Ricerche, IGAG, c.o. Dipartimento Scienze della Terra, Sapienza Università di Roma, P.le A. Moro 5, 00185, Rome, Italy.
Phone: +39 06-49914955
Skype: a.billi
Email: [log in to unmask]
Web site: http://www.andreabilli.com
_________________________________________________
Dalla Costituzione della Repubblica Italiana Art. 9: "La Repubblica promuove lo sviluppo della cultura e la ricerca scientifica e tecnica."
Art. 33: "L'arte e la scienza sono libere e libero ne è l'insegnamento."
"Non è grave il clamore chiassoso dei violenti, bensì il silenzio spaventoso delle persone oneste." Martin Luther King
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