Many lakes in western North America are cyclical, becoming deep and large during stadials and shallow and small during interstadials. Lake Alamosa briefly reached elevations of at Hansen Bluff four times during its history. According to modelling, ongoing sedimentation in the lake basin would have led to gradually increasing water levels during each stadial over time. Aside from climatic influences, the Bishop Tuff eruption of the Long Valley caldera in California and the Huckleberry Ridge eruption of the Yellowstone Caldera deposited tephra in Lake Alamosa. Sedimentation occurred in the basin floor, although slip along the Sangre de Cristo fault to the east created accumulation space.