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Four phases of deformation have been recognised: a phase of flattening-shearing deformation with the formation of synfoliation folds; a phase of E-W shortening, folding and steepening the bedding and foliation along approximately N-S trends; a phase of minor folding with open folds and local crenulations; and transcurrent, generally dextral faulting offsetting the phosphate beds. Thickening by repetition took place during the first phase, while steepening during the second phase has resulted in local swellings parallel to the near-vertical foliation that disappear rapidly with depth. The third phase of deformation introduced irregularities of orientation and the fourth has cut the deposit into offset blocks., Four phases of deformation have been recognised: a phase of flattening-shearing deformation with the formation of synfoliation folds; a phase of E-W shortening, folding and steepening the bedding and foliation along approximately N-S trends; a phase of minor folding with open folds and local crenulations; and transcurrent, generally dextral faulting offsetting the phosphate beds. Thickening by repetition took place during the first phase, while steepening during the second phase has resulted in local swellings parallel to the near-vertical foliation that disappear rapidly with depth. The third phase of deformation introduced irregularities of orientation and the fourth has cut the deposit into offset blocks.

The deposits are of high quality, but exploitation is complicated by the geometry of the deposits and the low reserves (a few million tonnes per deposit)., The deposits are of high quality, but exploitation is complicated by the geometry of the deposits and the low reserves (a few million tonnes per deposit).