Halogen chemistry and isotopic composition in McMurdo lake waters and pore fluids

As part of a collaborative investigation between researchers at Rice University, Arkansas State University,
University of Rochester, and Ohio State University, lakes of the McMurdo Dry Valleys were sampled at discreet depth
intervals during the 2005-2006 field season. Sample splits were subsequently analyzed for chemical and isotopic
composition of both gases and dissolved ions, as well as dissolved organic carbon. In addition, cryogenic salts were
sampled in the surrounding lake shores in order to determine the salt sources. Gravity cores were also obtained and
the pore waters were collected by centrifuging the wet sediment. Presented in this file are the dissolved halogens :chloride, bromide, and total iodine in lake waters and
pore waters. The isotopic composition of I-129 and Cl-36 are also presented for these same samples, as are the
molar ratios of I-129/I-127, and Cl-36/Cl-37. Alkalinity was also determined in order to subsequently investigate the
relationship between the oxidation of organic matter and the release of iodine into the lake waters.