Soru

### Models of the Grand Canyon's Formation

The Grand Canyon in Arizona is one of the most prominent geological features on Earth. Geologists agree that the canyon was formed primarily by the action of the Colorado River, and that the modern carving process began approximately $5$ to $6$ million years ago. However, they debate the speed and mechanism of the carving.

#### Model 1 (Catastrophic Spillover Model)
Model 1 proposes that the Grand Canyon was carved very rapidly by a catastrophic spillover event. According to this model, a large ancient lake, Lake Bidahochi, located on the Colorado Plateau, breached its eastern boundary about $6$ million years ago. The sudden, high-velocity drainage of this massive lake released immense volumes of water, carving the canyon down to near its current depth within a span of just a few weeks to months. In this view, the Colorado River did not carve the canyon slowly; rather, it simply occupied the pre-existing, catastrophically carved canyon after the flood subsided.

#### Model 2 (Steady Erosion Model)
Model 2 proposes that the Grand Canyon was carved gradually over millions of years by steady river erosion. According to this model, as the Colorado Plateau slowly uplifted over the last $6$ million years, the Colorado River maintained its course, acting like a giant band saw. The river steadily eroded the rock at a rate of approximately $0.1$ to $0.2\text{ mm/yr}$, matching the rate of regional tectonic uplift. This model asserts that there was no single catastrophic flooding event; instead, typical seasonal fluctuations and persistent river flow over millions of years accounts for the canyon's deep incision.

Based on the passage, match each of the geological descriptions with the model or models it represents.