NASA NTRS1989
Great Salt Lake level fluctuations from 13,000 yr B.P. to the present were interpreted by examination of shoreline geomorphic features, shoreline deposits, archeologic sites, isotopic data, and palynologic data. After the conclusion of the Bonneville paleolake cycle, between 13,000 and 12,000 yr B.P. the lake regressed to levels low enough to deposit a littoral oxidized red bed stratum and a pelagic Glauber's salt layer. A late Pleistocene lake cycle occurred between 12,000 and 10,000 yr B.P. depositing several beaches, the highest reaching an altitude of about 4250 ft (1295.3 m). The lake regressed after 10,000 yr B.P., only to rise to 4230 ft (1289.2 m) between 9700 and 9400 yr B.P. and then gradually lower at least 15 ft (4.5 m) or more. Lake levels fluctuated between 4212 and 4180 ft (1284 and 1274 m) for the next 4000 years. A late Holocene lake cycle, constrained by radiocarbon ages between 3440 and 1400 yr B.P., is reported at a highest static level of 4221 ft (1286.5 m). After a lake level drop to altitudes ranging between 4210 and 4205 ft (1283.2 and 1281.6 m), a 4217 ft (1285.7 m) level was reached after 400 yr B.P. This level lowered to 4214 ft (1284.4 m) in the mid to late 1700 s A.D. The lake levels have since stabilized aroung a 4200 ft (1280 m) mean.