The broad, gentle-sloping apron of sediment forming the Tonto Platform in the Grand Canyon was eroded from the Bright Angel Shale, a key unit of the Tonto Group contributing to this distinct plateau.
The broad, gentle-sloping apron of sediment known as the Tonto Platform in the Grand Canyon was predominantly eroded from the Bright Angel Shale. When observing the stratigraphy of the Grand Canyon, the Bright Angel Shale is a significant unit of the Tonto Group, which largely makes up the Tonto Platform.
The sedimentary deposits of the Bright Angel Shale have been shaped over time by weathering and erosion, contributing to the distinct plateau that we see today. The Tonto Platform is an intermediary landscape feature between the Inner Gorge's steep cliffs and the upper canyon's rim, revealing the extensive geological history of the Grand Canyon.
The Bright Angel Shale is the primary source that formed the Tonto Platform through long-term geological processes. This illustrates the intricate interplay between sedimentary layers and erosional forces that shape stunning landscapes like the Grand Canyon.