Approved By:

• Main Authors: Heather Elizabeth Pugh, Dr. W. Berry Gyons
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2002
• Subjects: Austral; Bonney; Fryxell; Hoare; McMurdo Dry Valleys; Taylor Valley; Victoria Land; Antarc*; Antarctica
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.540.3442

This thesis is part of the McMurdo Dry Valleys (MCM) Long-Tern Ecological Research (LTER) study in Southern Victoria Land, Antarctica. With the exception of the ice-covered lakes, there is little liquid water present in the valleys for most of the year. Chemical weathering is thought to occur more readily in warm and wet climates, however recent research has shown that it can occur in cold and dry environments. The chemical weathering of rocks and sediments in Taylor Valley occurs in the stream channels when liquid water is present, resulting from the melting of glacial ice during the austral summer. Not only is silicon an important element geologically, it is an important biogeochemical element, as aquatic microorganisms, such as diatoms, need it for growth. Silica (Si) is thought to be one of the chemicals that is dissolved by the glacier meltwater as it flows into the lakes. This thesis is an aqueous geochemical study of the Si found in the streams and lakes. Water samples were collected at the beginning of the austral summer and then again in midsummer from Lakes Bonney, Fryxell and Hoare in the Taylor Valley for the