PI-39 Commonly Asked Questions About Utah's Great Salt Lake and Ancient Lake Bonneville

The 1,200-foot-tall smoke stack at the southern end of the lake. This photo also shows Lake Bonneville terraces (levels) and the flooding of 1986.

What is the tall smoke stack at the south end of the Great Salt Lake?

The 1,200-foot-tall smoke stack at the southern end of the lake is part of the Kennecott Copper Company's copper ore-smelting operation. Ore for this smelter comes from the Bingham Canyon copper mine, which is the largest open-pit excavation on earth. The Bingham Canyon mine, started in 1906, is located approximately 15 miles to the south of the lake on the eastern side of the Oquirrh Mountains.

What are the round, white sand grains that make up the beaches?

The round, brown-to-white grains that make up many of the beaches around the lake are called oolites. Oolites are small spherical to elongated grains composed of concentric layers of calcium carbonate built up around a central core, much like a pearl. The core material is usually a small mineral grain, or a brine shrimp fecal pellet.

Some of the most beautiful beaches around the lake are composed of oolitic sand.

Magnified view of typical oolites (left), and oolite cross section (right) showing concentric layers built up around a central mineral fragment.