Yellowstone Lake is a prominent natural feature within Yellowstone National Park. Situated at an elevation of approximately 7,732 feet (2,357 meters) above sea level, it holds the distinction of being North America’s largest high-elevation lake. This vast body of water plays a central role in the park’s diverse ecosystem and offers a striking landscape.
Measuring the Depths
Yellowstone Lake reaches a maximum depth of 394 to 410 feet (120 to 125 meters). Its average depth is considerably shallower, around 139 to 140 feet (42 to 43 meters). Depths are determined through bathymetric surveys using sonar technology to map the lakebed.
The lake covers an expansive surface area of approximately 132 to 136 square miles (342 to 350 square kilometers), making it the largest body of water in Wyoming. Its substantial surface area and varying depths create a diverse underwater topography. Research vessels, such as the R/V Annie with its remotely operated vehicle “Yogi,” have been instrumental in exploring and mapping these underwater environments.
Geological Story of Its Formation
Yellowstone Lake’s formation is tied to the region’s volcanic history and its location within the Yellowstone Caldera. This massive depression formed approximately 640,000 years ago, following a supervolcano eruption. The eruption emptied a vast magma chamber beneath the surface, leading to the collapse of the overlying land and creating the immense basin that now holds the lake.
The northern two-thirds of the lake’s irregularly shaped basin occupies the southeastern portion of this caldera. Subsequent lava flows partially filled the caldera, further shaping the lakebed. The lake’s current configuration, including its south-tilting basin, is influenced by the ongoing rise and fall of “resurgent domes,” which are areas of uplift caused by subterranean magma movements.
Unique Characteristics of Its Deep Waters
Yellowstone Lake’s deep waters exhibit features linked to underlying geological activity. Numerous hydrothermal vents and geysers are present beneath the lake’s surface. These features are a significant part of the world’s largest continental hydrothermal system, with some of the hottest vent temperatures recorded in the park, reaching up to 170°C (340°F).
These underwater thermal features create localized warm spots within the otherwise cold lake, which maintains an average water temperature of around 41°F (5°C) throughout the year. The hydrothermal activity influences the lake’s ecosystem by introducing minerals and nutrients, supporting unique microbial communities and influencing the types of organisms that can thrive in these conditions.