| Las Vegas Bay in Lake Mead, NV provides a unique mid-scale natural laboratory to study the effects changes in lake level, sediment supply, fluvial discharge and basin physiography have had on stratigraphy of the basin. Mapping, seismic, sidescan sonar and bathymetry surveys, in conjunction with sediment cores, LPSA and 137Cs analyses were integrated to develop a temporal basin filling model for Las Vegas Bay. The evolution of the basin is divided into two periods based on lake history and stratigraphy data: an early 1935--1964, and a latter 1965--2002 period. Changes in lake history are more clearly preserved during the latter period because of higher sedimentation rates and more varied sediment types. Physiography has played a significant role in controlling the spatial distribution of sediment throughout the basin. Sand is observed on the basin floor where there are bends in the main channel, where breaks in slope occur and where lateral tributaries debouch into the main channel axis. |
