Porphyry Island
Encyclopedia
Porphyry Island is an island
in Unorganized Thunder Bay District
in northwestern
Ontario
, Canada
. It is the last island in a chain stretching south west of the Black Bay Peninsula
in Lake Superior
. It is located about 6 kilometres (4 mi) from Edward Island Provincial Park, 13 kilometres (8 mi) from Sleeping Giant Provincial Park
, 14 kilometres (9 mi) east of Silver Islet, Ontario
, and 42 kilometres (26 mi) kilometres east of the city of Thunder Bay
.
The island and nature reserve take their name from the characteristic quartz
and feldspar
crystals, or porphyries
found in the volcanic rocks.
The entire 107 hectares (264 acre) island constitutes the Porphyry Island Provincial Park
or nature reserve.
Island
An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or lake may be called an eyot , or holm...
in Unorganized Thunder Bay District
Thunder Bay District
Thunder Bay District is a district and census division in Northwestern Ontario in the Canadian province of Ontario. The district seat is Thunder Bay....
in northwestern
Northwestern Ontario
Northwestern Ontario is the region within the Canadian province of Ontario which lies north and west of Lake Superior, and west of Hudson Bay and James Bay. It includes most of subarctic Ontario. Its western boundary is the Canadian province of Manitoba, which disputed Ontario's claim to the...
Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. It is the last island in a chain stretching south west of the Black Bay Peninsula
Black Bay Peninsula
Black Bay Peninsula is a volcanic peninsula in Unorganized Thunder Bay District in Northwestern Ontario, Canada, located on the North Shore of Lake Superior. It separates Black Bay and Nipigon Bay and consists of over 300 flood basalt lava flows. Porphyry Island, an island entirely encompassed...
in Lake Superior
Lake Superior
Lake Superior is the largest of the five traditionally-demarcated Great Lakes of North America. It is bounded to the north by the Canadian province of Ontario and the U.S. state of Minnesota, and to the south by the U.S. states of Wisconsin and Michigan. It is the largest freshwater lake in the...
. It is located about 6 kilometres (4 mi) from Edward Island Provincial Park, 13 kilometres (8 mi) from Sleeping Giant Provincial Park
Sleeping Giant Provincial Park
Sleeping Giant Provincial Park, established in 1944 as Sibley Provincial Park and renamed in 1988, is a park located on the Sibley Peninsula in Northwestern Ontario, east of Thunder Bay. The nearest communities are Pass Lake, located at the northern entrance to the park, and Dorion, located NW,...
, 14 kilometres (9 mi) east of Silver Islet, Ontario
Silver Islet, Ontario
Silver Islet refers to both a small rocky island and a small town site located at the tip of the Sibley Peninsula in northwestern Ontario. It was the first silver mine in Ontario....
, and 42 kilometres (26 mi) kilometres east of the city of Thunder Bay
Thunder Bay
-In Canada:Thunder Bay is the name of three places in the province of Ontario, Canada along Lake Superior:*Thunder Bay District, Ontario, a district in Northwestern Ontario*Thunder Bay, a city in Thunder Bay District*Thunder Bay, Unorganized, Ontario...
.
The island and nature reserve take their name from the characteristic quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...
and feldspar
Feldspar
Feldspars are a group of rock-forming tectosilicate minerals which make up as much as 60% of the Earth's crust....
crystals, or porphyries
Porphyry (geology)
Porphyry is a variety of igneous rock consisting of large-grained crystals, such as feldspar or quartz, dispersed in a fine-grained feldspathic matrix or groundmass. The larger crystals are called phenocrysts...
found in the volcanic rocks.
The entire 107 hectares (264 acre) island constitutes the Porphyry Island Provincial Park
Porphyry Island Provincial Park
Porphyry Island Provincial Park is a remote, non-operating protected area in Unorganized Thunder Bay District in northwestern Ontario, Canada. It is located on Porphyry Island off the tip of the Black Bay Peninsula on the North Shore of Lake Superior...
or nature reserve.