6 marker horizons recognised: (1) - White dolomite (approx. 100 thick). Well developed green chloritic mineral along stylolites. High porosity. Frequent Archaeocyathinae. (2) - Uppermost oolite (3-11' thick). Ooliths white in colour, 1/16 inch diameter. (3 )- Slumped or algal member (17-20' thick). Dark to light grey. Laminae contorted and sometimes brecciated. Porosity very low. (4) - Marly bed (2-5' thick). Light grey, shaley, laminated, cross-bedded, feels powdery. Pyrite on fractures. (5) - Pisolitic ?algal bed (1/2-1' thick). Grey, pisolites up to 2/3 inch diameter, alternating dark and light concentric 1/20 inch layers. (6) - Oolites, calcareous and orthoquartzites. Primary brecciation, lastic origin. Ooliths black, partly silicified, up to 1/6 inch diameter. Tests (described) on 9 samples from bore holes, 2, 4, and 8 showed that upper 200 ft. of Cambrian section is largely dolomitised, while lower portion is also dolomitised, but to a lesser extent. Possibly due to the fact that upper sequence is porous biohermal facies while lower portion is bedded lagoon facies. May also be related to proximity of unconformity surface.