The general features of the antiform include an axial planar orientation of 148°/54° SW with a fold hinge line, which plunges 7°/153° (Taken from stereonet - figure 8). The limbs of the antiform dip to the Northeast and Southwest respectively.

The Northeast limb has shallow dips that average 27° although variation was observed between 9° and 59°. Park (1970) has explained this variation as being caused by development of monoclinal folds which cause local flattening or reversal of dips, this explanation seems reasonable although due to the limited area of the north east limb mapped it could not be satisfactorily verified. The scale of the gneissose banding on this limb varied between 40 and 5 millimetres with the average banding thickness being towards the narrower end of this range . On this limb, the polyphase nature of the deformations in the Tollie gneiss could be readily observed.

The Southwest limb has steep dips of between 60° -90° The gneissose banding is observed to be much thinner than on the north east limb being on the scale of 2-4 millimetres in thickness. It was also noted that that polyphase nature of the deformations was more difficult to observe on this limb.

Overall, the strike of the foliation surfaces is 150° ± 10° with the strike on the north eastern limb being around 160° and on the south western limb around 140° -150°

The Gneisses are observed to have undergone five separate phases of deformation.

The first phase of deformation is represented by the gneissose banding which has been fully described in the Tollie gneiss unit description. Following the formation of the gneissose banding the first suite of amphibolite sheet precursors was intruded (see below).

The second phase of deformation formed upright isoclinal folds (with no associated foliation observed).

The third phase of deformation is characterised by recumbent tight folds which have an associated foliation (S3) (figure 6 and figure 7) and a quartz rodding intersection lineation (Plate 5). The D3 structures are observed to affect the D2 isoclinal folds that are refolded (Figure 6 and figure 7)).

Both the second and third deformations are observed to affect an amphibolite sheet on the north eastern limb of the antiform (Plate 6) (NGR 84877860). However the S3 foliation is observed to be cross-cut by an amphibolite sheet at Location 1 (NGR 84907872) thus suggesting that a second period of amphibolite sheet precursor intrusion occurred post D3 (Figure 6).

Following the intrusion of the precursors of the second amphibolite sheet suite a major deformational event formed the Tollie Antiform and metamorphosed the second suite of sheets to give the amphibolites which also developed a foliation and/or lineation in the amphibolite sheets. During the fourth deformation - Boudinage, rotated boudinage and "pinch and swell" structures were formed in the amphibolite sheets in the core of the antiform and on the south west limb of the antiform. The rotated boudinage is restricted to the core of the antiform. The presence of boudinage and "pinch and swell" structures on the Southwest limb does not imply a separate deformation, although it shows that the rocks affected have undergone a tensional regime. This is shown by the strain ellipse which shows that if the area is undergoing tension in a particular section of the ellipse then compression (folding) will occur in another area of the ellipse, thus these structures can be assigned to the fourth deformational event.

Minor parasitic folds on the Southwest limb are associated with the fourth deformation as their vergence is controlled by the Tollie Antiform.

The fifth deformation phase is characterised by minor brittle kink folds on the folded S3 foliation surfaces (Plate 7). In this the final deformation in the Tollie gneiss, Pegmatite’s have been intruded along with a period of faulting (the relative timing of these two events could not be deduced as no cross-cutting relationships could be observed). The intrusion of the Apilite sheets could not be definitely dated but they may possibly be associated with the pegmatite dyke intrusions.