Dear all,
It seems that the debate about stretching lineations parallel to fold
axes is "always" restricted to sheath folds. But, this in most cases
is not what we find in the field and also at map scale. I think it is
also what Wojtek probably meant with his message.
Here are some references that might be useful:
* a theoretical approach to flow regimes where non-coaxial components
of deformation might be perpendicular to maximum finite stretching:
-Passchier, C.W. 1998. Monoclinic model shear zones. J. Struct.Geol.
20, 1121-1137.
* a natural example of fold axes (with asymmetric profiles but not
sheath geometries) and stretching lineation being parallel to each
other at regional scale:
- Dias and Ribeiro, 1995. The Ibero-Armorican Arc: A collision effect
against an irregular continent?. Tectonophysics 246, 113-128.
* another natural example from the Caledonides:
- Gilotti and Hull, 1993. Kinematic stratification in the hinterland
of the central Scandinavian Caledonides. J. Struct. Geol. 15, 629-646.
* and an experimental study,
-Grujic and Mancktelow, 1995. Folds with axes parallel to the
extension direction: an experimental study. J. Struct.Geol. 17,
279-291.
I hope this helps.
Cheers,
Sergio
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