Collection of thin sections and polished sections from Alaska (DGGS)
Summary
The legacy thin section collection represents petrographic thin sections collected by DGGS geologists for field projects involving geologic mapping in areas of Alaska with a focus to study the potential and controls of mineral and energy resources. As part of the mapping process, rocks were collected for petrographic work to provide information for discriminating between various rock types and to write unit descriptions of the final rock types or units represented on geologic maps resulting from the field work. The collection represents 27 years or more of work and over 15,000 outcrop thin sections from all over Alaska and a wide variety of field geologists. Samples are housed in various locations within the DGGS office with approximately [...]
Summary
The legacy thin section collection represents petrographic thin sections collected by DGGS geologists for field projects involving geologic mapping in areas of Alaska with a focus to study the potential and controls of mineral and energy resources. As part of the mapping process, rocks were collected for petrographic work to provide information for discriminating between various rock types and to write unit descriptions of the final rock types or units represented on geologic maps resulting from the field work. The collection represents 27 years or more of work and over 15,000 outcrop thin sections from all over Alaska and a wide variety of field geologists. Samples are housed in various locations within the DGGS office with approximately 2000 slides inventoried. Most thin section slides are either on cards or in cases. Nearly all thin sections have a unique field number etched or written on the thin section with the format of year, geologist initials, field number. The samples consist of 90 percent petrographic, and some micropaleo. Most micropaleo are sent to the Alaska Geologic Material Center and are included in that catalog.
Please contact DGGS at dggspubs@alaska.gov to determine the availability of thin sections stored at our office. For all other requests for GMC materials, please contact the GMC staff at 907-696-0079 or visit the website http://dggs.alaska.gov/gmc/ to arrange a visit
Purpose
Thin sections are used to determine mineralogy of the rock, grain size and relative abundances of minerals, metamorphic grade, degree of weathering, and degree of alteration, among other criteria. Information from the petrographic work is also used to determine suitability of the collected sample for further studies, including whole-rock geochemistry, radiometric dating, mineral chemistry studies, and possible geothermometry and geobarometry studies.
Rights
All materials are owned by the Alaska Division of Geological and Geophysical Surveys. Any thin sections that have been sent to the Alaska Geologic Material Center are available to the public for examination except those designated by the Curator as confidential. Please view the use and access constraints on the Geologic Materials Center website: https://dggs.alaska.gov/gmc/access-samples.html
This collection has been reviewed and updated by funding from FY 2020 National Geological and Geophysical Data Preservation Program, award number G19AP00077.