Watts Point volcanic centre

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Watts Point volcanic centre
Elevation	~ 240 m (800 ft)
Location	British Columbia, Canada
Range	North Shore Mountains
Coordinates	49°39′N, 123°13′W
Topo map	NTS 92G/11 Squamish
Type	Subglacial mound
Age of rock	~ 90,000–130,000 yrs
Last eruption	~ 90,000 yrs

The Watts Point volcanic centre is a small outcrop of volcanic rock in British Columbia, Canada, located on the eastern shore of Howe Sound about 10 kilometres (6 mi) south of Squamish and 40 kilometres (25 mi) north of Vancouver. It is the southernmost volcanic center in the Garibaldi segment of the Cascade Volcanic Arc, and the latest research indicates that it is most likely a subglacial volcano. It comprises a continuous mass of sparsely porphyritic highly jointed dacitic lava overlying the mid-Cretaceous Coast Plutonic Complex and overlain locally by clay and of glacial till.

The volcanic outcrop at Watts Point extends from below the present sea level up the side of a steep slope over 240 metres (800 ft). The outcrop is less than 1 kilometre (0.6 mi) long, with an area of about 0.4 square kilometres (0.2 sq mi) and an eruptive volume of roughly 0.02 km³ (0.005 cu mi). The location is heavily forested, and the BC Rail mainline passes through the lower portion of the outcrop about 40 m (130 ft) above sea level. Two railroad track ballast quarries, one near the middle and the other near the upper edge, provide the best exposure of the interior of the lava mass.