Page 10 - Curriculum Visions Dynamic Book

Salt lakes
Geologists call dry desert lake beds “playas” after the Spanish word for beach. It is likely that such lakes produced thick beds of salt in the past, too. These have since been buried by other rocks and the minerals have become compacted into rock. One layer of such minerals makes up rock salt, the mineral described on the previous page.
Salt shores
 This picture shows a playa lake in Death Valley.
The white band along this lake shore is salt. It has been produced by the heat of the sun on the sediments surrounding the lake. As the sun heats the sediment, it draws water from the lake and up to the surface, where it is evaporated. The minerals in the solution are left behind as a white crust, most of which is salt. Salty shorelines by the sea are produced by the same effect.
 The picture above shows a shoreline where evaporation is intense. The white deposits are salt.
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