Gow
Key facts
- Country
- Canada
- Diameter
- 4 km
- Age
- less than about 250 million years
- Location
- 56.45° N, 104.48° W
Gow Lake, a small lake in the forests of northern Saskatchewan, with a central island made of impact breccia and melt rock.
Gow is a small impact crater about 4 to 5 km across in northern Saskatchewan, in Canada, filled by the waters of Gow Lake, south of the much larger Reindeer Lake.
Discovery. The round lake, with an island in the middle, attracted the attention of geologists studying the Canadian Shield. On the central island they found impact breccia, rock made of broken fragments welded together, and impact melt rock, rock that was completely melted by the impact and then cooled. Microscopic shock features in quartz and feldspar confirmed that the structure was made by an impact. It was described in the 1980s.
What it hit. The impactor struck ancient crystalline rocks of the Canadian Shield, mainly granite and gneiss nearly 2 billion years old.
Structure. Although small, Gow is a complex crater with a central uplift, the island in the lake. Small craters on Earth are usually simple bowls, so Gow lies close to the size at which craters in hard crystalline rock begin to develop central peaks.
Age. The age is poorly known; it is generally thought to be younger than about 250 million years, and some dating of the melt rock points to roughly 200 million years.
Visiting. The lake is remote and best reached by floatplane. The impactor is unknown.
Did you know?
The island in the middle of Gow Lake is the crater's central uplift.
Rock melted by the impact can be found on the island.
Gow is one of the smallest craters on Earth with a central uplift.