Tuffs form most of the lower two-thirds of the facies, and nearly all of the claystones are in the upper one- third. ... The lake did not have an outlet and consequently fluctuated in level, alternately flooding and exposing a broad marginal zoneanbsp;...
|Title||:||Geology of the Olduvai Gorge|
|Author||:||Richard LeRoy Hay|
|Publisher||:||Univ of California Press - 1976-01-01|