As a water reservoir for Steamboat Geyser, it has an appropriate name. Brightly colored cyanobacteria distinguish the rounded terraces of this spring. Duration 3-15 minutes. Height 50-100 feet. The sinter, spine-covered crater reminded early visitors of the spiny sea urchin.
Echinus derives from the Greek word for spiny.
A light red-brown iron oxide deposited with silica colors this crater. It is the largest predictable geyser at Norris Geyser Basin. Before an eruption, water usually fills the basin to within two or three feet of the rim and begins boiling. Churning and splashing then trigger an eruption throwing water and steam upward in a series of explosive bursts. After an eruption the basin drains producing a whirlpool and a gurgling which sounds as if the stopper from a bath tub had been pulled.