snyder_salts English utf8 dataset McMurdo Dry Valleys LTER http://mcmlter.org/ 2014-11-04 ISO 19115-2 Geographic Information - North American Profile Metadata - Data with Biological Extensions ISO 19115-2:2009(E) Mineralogic composition of cryogenic evaporites determined by low-temperature X-ray diffactometry 2014-11-04 publication Glen Snyder Rice http://www.rice.edu/ (713) 348-4054 Earth Science-MS 126 Houston TX 77251 US gsnyder@rice.edu pointOfContact documentDigital 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 in the case of Lake Vanda, a white precipitate was recovered from the lake bottom.              Presented  in this file is the mineralogic composition of salt crusts that were collected on the surface of sediment and rocks surrounding the lakes, as well as the lake-bottom precipitate from Lake Vanda.  The results are based on low-temperature XRD determinations, and Rietveld refinement of whole peaks.              Name: Chris Gardner Role: data manager Name: Inigo San Gil Role: data manager completed McMurdo Dry Valleys LTER http://mcmlter.org/ unknown Metadata completed in 2016 This dataset was created Oct 1, 2008 by MCM-LTER information manager (Chris Gardner) after email discussion with PI Glen Snyder. inorganic nutrients theme LTER Core Areas English ground condition 2005-12-21 2005-12-27 This material is based upon work supported by the National Science Foundation under Grant No.0440686 https://mcm.lternet.edu/sites/default/files/ANCILLARY_SNYDER_SALTS.csv ANCILLARY_SNYDER_SALTS eng; US McMurdo Dry Valleys LTER ANCILLARY_SNYDER_SALTS Record Delimiter : \n Number of Header Lines : 27 Number of Footer Lines : 1 Orientation : Column Quote Character : "Field Delimiter : , false DATASET_CODE Table Identifier LOCATION_NAME Name of lake where measurement was made Location_Type Sample type description and/or location Sample_ID Sample identification code Latitude Sample Latitude Longitude Sample Longitude Date_time Date sample was collected Date Time Format: mm/dd/yyyy Halite Percent composition of halite Antarcticite Percent composition of Antarcticite Thenardite Percent composition of Thenardite Mirabilite Percent composition of Mirabilite Gypsum Percent composition of Gypsum Calcite Percent composition of Calcite Aragonite Percent composition of Aragonite Quartz Percent composition of Quartz Albite Percent composition of Albite DBF https://mcm.lternet.edu/sites/default/files/ANCILLARY_SNYDER_SALTS.csv dataset  Salts were collected in the areas surrounding the Dry Valley lakes. The samples were bagged and then placed either in boxes or in plastic containers in order to avoid crushing them. The samples were stored in a freezer at -40 C, prior to shipping, due to the instability of Antarcticite at room temperatures. The samples were then shipped under dry ice to Rice University in Houston, then shipped to the Steacie Institute for Molecular Sciences  in Ottawa, which is a division of the Canadian Research Council.            Hailong Lu, a research scientist in the Institute whose specialty is on the structure of marine gas hydrates, placed each sample in a mortar with liquid nitrogen and then ground it into a powder. The powders were then analyzed with a low-temperature XRD. Temperatures were first dropped to -140 C, then gradually  ramped up to room temperature to look at phase changes that occurred on warming. Minerals were identified JADE 8.5 data processing software, and the ICDD PDF-2 Data Base. The relative abundance of each crygenic mineral was dertermined by the Rietveld method of whole-peak fitting.   Metadata Access Constraints: none Metadata Use Constraints: none annually McMurdo Dry Valleys LTER http://mcmlter.org/ pointOfContact