Ž . Chemical Geology 154 1999 113–132 Permian paleoclimate data from fluid inclusions in halite Kathleen Counter Benison a,b, ) , Robert H. Goldstein a a The Department of Geology, The UniÕersity of Kansas, Lawrence, USA b The Kansas Geological SurÕey, Lawrence, KS, USA Abstract This study has yielded surface water paleotemperatures from primary fluid inclusions in mid Permian Nippewalla Group halite from western Kansas. A ‘cooling nucleation’ method is used to generate vapor bubbles in originally all-liquid primary inclusions. Then, surface water paleotemperatures are obtained by measuring temperatures of homogenization to liquid. Homogenization temperatures ranged from 218C to 508C and are consistent along individual fluid inclusion assemblages, indicating that the fluid inclusions have not been altered by thermal reequilibration. Homogenization temperatures show a range of up to 268C from base to top of individual cloudy chevron growth bands. Petrographic and fluid inclusion evidence indicate that no significant pressure correction is needed for the homogenization temperature data. We interpret these homogenization temperatures to represent shallow surface water paleotemperatures. The range in temperatures from base to top of single chevron bands may reflect daily temperatures variations. These Permian surface water temperatures fall within the same range as some modern evaporative surface waters, suggesting that this Permian environment may have been relatively similar to its modern counterparts. Shallow surface water temperatures in evaporative settings correspond closely to local air temperatures. Therefore, the Permian surface water temperatures determined in this study may be considered proxies for local Permian air temperatures. q 1999 Elsevier Science B.V. All rights reserved. Keywords: Lacustrine sediments; Evaporites; Nonmarine; Nippewalla group; Homogenization temperatures 1. Introduction Burgeoning interest in paleoclimatology has re- sulted from new data on changes in the earth’s atmosphere and a desire for predictions of future climate change. How better to understand natural fluctuations in climate than to obtain a record of climate data from the past? This study uses fluid inclusion data from Permian halite to construct a record of ancient earth surface temperature. ) Corresponding author. Department of Geology, Central Michigan University, Mt. Pleasant, MI 48859, USA. E-mail: kathy.benison@cmich.edu Evaporite deposits appear to be a treasure chest of paleoclimate data. The formation of salt minerals at the earth’s surface is extremely sensitive to local climatic conditions. Primary fluid inclusions pre- served in depositional evaporite minerals may be remnants of ancient hydrosphere and atmosphere. Fluid inclusion studies can yield detailed information about the water temperatures, water chemistries, and even atmospheric conditions under which evaporites formed. Geologists have maintained a healthy skepticism toward fluid inclusion data from evaporites, espe- Ž cially halite Roedder and Skinner, 1968; Wilcox, 1968; Kovalevich, 1975, 1976; Petrichenko, 1979; Roedder and Belkin, 1980; Roedder, 1984b; Gold- 0009-2541r99r$ - see front matter q 1999 Elsevier Science B.V. All rights reserved. Ž . PII: S0009-2541 98 00127-2