I seem to remember a model for formation of fold-like geometries in mylonite
zones, due to differential shear around competent bodies and/or zones that
have experienced much less shearing strain than the surrounding matrix. This
produced 'folds' parallel to the transport direction that were not a product
of fold rotation. From memory the paper was by Bell and Hammond on the
internal geometry of mylonite zones. Then again, maybe I have remembered
this totally incorrectly...
Brett
----- Original Message -----
From: "S. Mitra" <[log in to unmask]>
To: "geo-tectonics" <[log in to unmask]>
Sent: Tuesday, 7 November 2000 6:59
Subject: Re: Something I always wanted to know, but I was afraid to ask :)
>
> hello,
> well this ia a thing which is related to subsequent stages of shearing
> when the cylindrical folds with fold axes perpendicular to the transport
> direction gets dragged down forming seath folds, with a hair pin bend
> developed on the fold axis. this might seemingly look as if the fold axes
> were parallel to the stretching lineations.
>
>
> thank you,
>
>
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>
> SUPRIYO MITRA
> -----------------
> St. JOHN'S COLLEGE
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>
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>
>
>
> On Tue, 7 Nov 2000, Wojciech Czaplinski wrote:
>
> > Hello,
> > Before I say farewell and unsubscribe from this group, there is one
> > question I want to ask:
> > It is commonly believed, that stretching lineation in the shear zones
> > marks the direction of tectonic transport. So why the hell is it usually
> > parallel to the folds' axes? Seems in contrary to me...
> >
> > greetings - Wojtek
> >
>
>
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