sheath fold

Entire sheath folds are rarely found in outcrops; more commonly cross-sections are exposed where the fold geometry is manifested by closed layers so-called eye 

Experimental study of sheath fold development around a weak inclusion in a mechanically layered Even though sheath folds have been used to infer strain.

The Wadi Mayh sheath fold in north-eastern Oman is one of the largest and best-exposed. 10 sheath folds known and presents a unique opportunity to better 

19 Jan 2016 Sheath folding. Introduction. The Bergslagen ore district in south-central Sweden (Fig. 1a) is host to a large number of iron oxide and base ...

large-scale structure and to define the sheath fold shape. Keywords: Ligurian Alps; Briançonnais; structural map; sheath folds; geological mapping.

Sheath folds. A sheath fold has a strongly curved hinge line sweeping around through an arc of more than 90° up to the hairpin bend. Sheath folds contain a 

Foxe Fold Belt. It is concluded that sheath folds may have formed in a deep-crustal horizontal shear regime below a thick nappe. REGIONAL GEOLOGY.

Mesoscopic structures typical of ductile shear zones are observed and include mylonitic foliation stretching lineation

'Z') are consistent with the sheath-fold interpretation. Sheath folds are locally numerous in the Moretti-Harrah quarry but are not widely distributed in 

the late stages of sheath-fold formation the deformation became non-rotational. INTRODUCTION. Trm sa'auc'rLr~s described in this paper occur in a layer.

The sheath fold is enveloped by Ordovician and older rocks that do not show equal amounts of internal deformation The upper bounding envelope is a detachment that has been subsequently sheath

Sheath folds are associated with shear zones and have beenused as high strain indicators We present results from athree-dimensional analytical study showing that the ?owperturbation around a

(A) Sheath fold from Cap de Creus Spain (B) Photo from a physical experiment investigating the impact of layer viscosity contrast on the fold formation (Reber et al 2013) (C) Cross section from an analytical model investigating the effect of total shear strain (Reber et al 2012)

A sheath fold is a highly non-cylindrical fold with a hinge angle (Fig 2a) less than 90 (Skjernaa 1989); the hinge angle is measured between the parts of the hinge line that have rotated

Sheath folds can develop in pure shear flow (e g Ghosh and Sengupta 28 1984) however due to their common occurrence in high strain shear zones their formation is 29 often associated with simple shear dominated flow regimes (Cobbold and Quinquis 1980)