Sex for chet - Dating method glaciation

These rocks, originally ranging in composition from basalt to rhyolite, are most common near the Sierra crest.

In the northern canyons of the study area, Paleozoic metasedimentary rocks including sandy marbles and biotite schist replace the metavolcanic pendants.

lakes were rare; one (Sawmill Meadow) was completely sedimented.

Plutons are rather small, and individual drainages generally include more than one.

In the southern part of the study area, Jurassic-Triassic metavolcanic rocks are found as roof pendants.

Those Hilgard terminal moraines which were found have been barely breached by streams.

Moraines tend to be heavily forested, and lakes are largely unsedimented.

The youngest glaciers (Matthes glaciation) left unconsolidated and unvegetated till in stagnant rock glaciers and moraines in cirques on high peaks. Extending out from the cirques and into the upper reaches of the canyons are moraines correlating to the Recess Peak glaciation.

Till is generally consolidated and supports heavy lichen growth and bushes but few trees.

Weathering of boulders in Tenaya moraines was similar, but a small fraction of granitic boulders were grusy.

Boulders from Tahoe moraines were conspicuously weathered, and the moraines themselves were rounded and gullied.

Traces of at least seven glaciations were found during this study.

Moraines and other deposits left during these glaciations could be distinguished based on the degree of weathering of granitic clasts, vegetative cover, and morphologic characteristics.

Absolute age limits were obtained for two of the Pleistocene glaciations by radiometric dating of basalt flows interfingered with the moraines.

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