Point Lake - Lac de Gras (Ekati)

Des levés en gravimétrie ont efficacement localisé des diatrèmes de kimberlites.

Lac de Gras is located 310 km northeast of Yellowknife and is the first economic diamond deposit found in Canada. Over 8000 kg of diamonds have been extracted from the kimberlite pipes in this region.

Kimberlite pipes often present a strong density contrast with surrounding rocks. A 2 mGal negative residual anomaly led to the discovery of the Lac de Gras kimberlite.