Kilbride #080102

(Calcium Pits)

Lowville Re-entrant Valley was formed in the Niagara Escarpment by rivers and glaciers. Late Wisconsinan, Port Huron Stadial outwash, spillway channels, Halton Till and Peel Ponds are found in the valley. Preglacial and Holocene fluvial and karst processes have also contributed to the valley's evolution. Surficial and bedrock features. Ancient meltwater channel with outwash fan. Variety of Karst features. Excellent exposure of Amabel formations at Rattlesnake Point

The Lowville reentrant valley is a wide bedrock valley measuring approximately 2.3 miles (5km) wide and 5 miles (8km) long. This valley trends in a northeast-southwest direction and is flanked by the Milton Outlier on the north and Mount Nemo on the south which are composed of steep Amabel bluffs that border the entrance to this valley. The relatively flat valley floor is covered in late Wisconsin, Halton Till, that has been planed down by the Peel Ponding, a very temporary proglacial lake.

The Niagara Escarpment is buried under an arc of glacial outwash material around the head of the reentrant valley near Kilbride. These deposits probably formed around the perimeter of an ice front as it began to withdraw from the reentrant valley. During stages of the last deglaciation the ice meltwaters followed topographic low areas such as the ancient meltwater channel flowing southeast from Campbellville. A well-developed outwash fan formed at the southern end of this.

The bedrock complex immediately south of Campbellville, extending toward Kilbride, was subject to both glacial and postglacial erosion and thus exhibits a variety of karst (solution weathered) features. Crawford Lake is thought to a sink hole; however its great depth may suggest another mode of origin. The abandoned meltwater channel which ran south from Crawford Lake during the last deglaciation left an abandoned waterfall about 1/2 mile (0.8km) south of Crawford Lake. The bedrock channel running through what is known as Calcium Pits was probably part of a glacial meltwater channel which has been filled in by outwash material. More recently, it has been filling with marl deposition which was, at one time, extracted commercially for lime.

The Lowville Re-entrant Valley contains a number of regionally significant glacial and late glacial earth science features. These include both surficial and bedrock features. The type section for the Halton Till is located on the west bank of Bronte Creek about 2 miles (3.2 km) east of Lowville. Unfortunately, as with many Pleistocene type sections, it has become overgrown with vegetation and is no longer clearly exposed. Excellent exposures of the Amabel Formation at Rattlesnake Point and Mount Nemo outline the sides of this major re-entrant valley.