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| Watts Point volcanic centre | |
|---|---|
  Watts Point volcanic centre Location in British Columbia | |
| Highest point | |
| Elevation | ~ 240 m (800 ft) |
| Coordinates | 49°39′10″N123°12′30″W / 49.65278°N 123.20833°W Coordinates: 49°39′10″N123°12′30″W / 49.65278°N 123.20833°W |
| Geography | |
| Location | British Columbia, Canada |
| Parent range | Britannia Range (North Shore Mountains) |
| Topo map | NTS 92G/11 Squamish |
| Geology | |
| Age of rock | ~ 90,000–130,000 years |
| Mountain type | Subglacial mound |
| Volcanic arc/belt | Canadian Cascade Arc Garibaldi Volcanic Belt |
| Last eruption | ~ 90,000 years |
The Watts Point volcanic centre is a small outcrop of Pleistocene age volcanic rock at Watts Point in British Columbia, Canada, about 10 kilometres (6 mi) south of Squamish and 40 kilometres (25 mi) north of Vancouver, and just north of Britannia Beach. It is the southernmost volcanic zone in the Squamish volcanic field and of the Garibaldi segment of the Cascade Volcanic Arc. The latest research indicates that it is most likely a subglacial mound. 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.
An outcrop or rocky outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth.
The Pleistocene is the geological epoch which lasted from about 2,588,000 to 11,700 years ago, spanning the world's most recent period of repeated glaciations. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology.
Volcanic rock is a rock formed from magma erupted from a volcano. In other words, it differs from other igneous rock by being of volcanic origin. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and metamorphic rocks and constitute an important element of some sediments and sedimentary rocks. For these reasons, in geology, volcanics and shallow hypabyssal rocks are not always treated as distinct. In the context of Precambrian shield geology, the term "volcanic" is often applied to what are strictly metavolcanic rocks. Volcanic rocks and sediment that form from magma erupted into the air are called "volcaniclastics," and these are technically sedimentary rocks.
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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 cubic kilometres (0.0048 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. BC Highway 99 climbs over the eastern shoulder of the complex before descending to the area of the Stawamus Chief and Murrin Park, south southeast of Squamish.
Mean sea level (MSL) is an average level of the surface of one or more of Earth's oceans from which heights such as elevation may be measured. MSL is a type of vertical datum – a standardised geodetic datum – that is used, for example, as a chart datum in cartography and marine navigation, or, in aviation, as the standard sea level at which atmospheric pressure is measured to calibrate altitude and, consequently, aircraft flight levels. A common and relatively straightforward mean sea-level standard is the midpoint between a mean low and mean high tide at a particular location.
BC Rail, known as the British Columbia Railway between 1972 and 1984 and as the Pacific Great Eastern Railway (PGE) before 1972, was a railway that operated in the Canadian province of British Columbia between 1912 and 2004. It was a class II regional railway and the third-largest in Canada, operating 2,320 km (1,440 mi) of mainline track. Its operations were owned by the public as a crown corporation from 1918 until 2004, when the provincial government leased operations for 999 years to CN. The track and other assets, including a marine division and stevedoring subsidiary as well as large tracts of real estate, remain under public ownership. 40 km of track serving the Roberts Bank Superport that were scheduled to be sold to OmniTRAX remain under BC Rail management due to that sale being cancelled because of the transaction being tainted by an influence-peddling and bribery scandal resulting in convictions in 2010. The provincial government, which promised when originally elected never to sell the railway, has announced that the crown corporation and its remaining operations and assets would be "wound down" and taken over by various departments of the Ministry of Transportation The details of the sale/lease to CN, which are related to the OmniTRAX affair, have become the subject of protracted public inquiry as part of the proceedings of the trial surrounding a scandal known as the British Columbia Legislature Raids Affair, or "Railgate". Government leaders and civil servants involved with the arrangements to CN have refused to comment on the deal because the matter "is before the courts".
Track ballast forms the trackbed upon which railroad ties (sleepers) are laid. It is packed between, below, and around the ties. It is used to bear the load from the railroad ties, to facilitate drainage of water, and also to keep down vegetation that might interfere with the track structure. This also serves to hold the track in place as the trains roll by. It is typically made of crushed stone, although ballast has sometimes consisted of other, less suitable materials, for example burnt clay. The term "ballast" comes from a nautical term for the stones used to stabilize a ship.
