MORAINE AND SHORELINE RELATIONSHIPS AT MONO LAKE, CALIFORNIA

Sierran glaciers reached Lake Russell in the late Pleistocene, and shore lines cut in lateral moraines of the next-to-last glacial stage (Tahoe) extend into troughs vacated by the ice at the close of that stage. During the waning phase of the last glacial stage (Tioga) conspicuous shore lines were carved on slopes bordering present Mono Lake. Terminal moraines of the Tioga stage, nested inside moraines of the preceding advance, reach the uppermost shore lines of Mono Lake and appear to be contemporaneous with its last expansion. Both the Tioga terminal and recessional moraines show that ice retreat was pulsatory, with several relatively long halts interrupting times of rapid recession. The comparatively stationary ice fronts probably can be correlated with broader lake terraces, the rapid ice withdrawals with narrower terraces.