Paleo Slide Set: Climate and the Classic Maya Civilization
Interpretation of how changes in the lake sediment record detail climate change

This illustration shows the simple working assumptions for interpreting changes 
in the sediment record in terms of climate (evaporation/precipitation). Top: Under 
conditions of wet climate (low E/P), we expect high lake levels, dilute concentrations 
of solutes, low 18O to 16Oratios in lake water and aquatic shells, and sediments 
consisting of mainly organic carbon and calcite. Middle: Under conditions of drier 
climate (moderate E/P), we expect lower lake levels, higher concentrations of dissolved 
solutes, higher ratios of 18O and 16O, and perhaps sediments dominated by calcite. 
Bottom: Under arid climate conditions (high E/P), we expect low lake levels (perhaps 
desiccation), high dissolved solute concentrations, high ratios of 18O and 16O and, in 
the case of Lake Chichancanab, sediments dominated by gypsum (CaSO4). 

Photo Credits:
Patty Catanzaro 
Department of Geology, University of Florida