Caption:
Aerial view southwestward across Campbell Lake toward the Mackenzie River -the lake occupies a segment of the Sitidgi Graben, part of an extensional block fault system that was active leading to the initial formation of the Beaufort Sea in Cretaceous time, more than 100 million years ago - the lake features an unusual reverse delta - normally, the stream drains water from Campbell Lake into the Mackenzie River, but during the Spring flood when the water level in the river is high, the flow reverses, bringing silt-laden water from the river into the lake - over time the silt has built up this reverse delta, filling up the centre of the lake