Pilot
Key facts
- Country
- Canada
- Diameter
- 6 km
- Age
- about 445 ± 2 million years
- Location
- 60.28° N, 111.00° W
Pilot Lake, a round lake about 6 km across in the forests of the southern Northwest Territories, near the border with Alberta and Saskatchewan.
Pilot is an impact crater about 6 km across, filled by the waters of Pilot Lake in the southern Northwest Territories of Canada, not far from the town of Fort Smith.
Discovery. The lake's round shape drew the attention of geologists searching for craters on the Canadian Shield. They found breccia and impact melt rock, carried from the crater by ice sheets, in glacial deposits around the lake. Microscopic shock features in quartz and feldspar confirmed that these rocks were made by an impact.
What it hit. The impactor struck ancient crystalline rocks of the Canadian Shield, mainly granite and gneiss nearly 2 billion years old or older.
Age. Argon dating of the melt rock gives an age of about 445 million years, at the end of the Ordovician, with an uncertainty of only a couple of million years.
Why it matters. Pilot is one of several Canadian craters, including Couture and Slate Islands, that formed in the Ordovician and Silurian, a period when many impacts seem to have struck the Earth. The impactor is unknown.
Visiting. The lake is remote and best reached by floatplane.
Did you know?
Pilot Lake fills a crater formed about 445 million years ago.
The impact rocks were found in glacial deposits around the lake.
It is one of several Canadian craters formed in the Ordovician and Silurian.