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GEOL 355: Structural Geology and Tectonics

Primary Source Literature

Primary sources are original sources of information that have not yet been filtered through analysis, examination or interpretation. They are written during the time period involved by the person(s) who conducted the research and are the result of original research or observation. Thus, primary source literature includes firsthand information on methodologies, data, results, and discussions of the findings. Primary source literature is typically published in scholarly, peer-reviewed journals.


Identifying Primary Research Articles

In primary research articles:

  • The abstracts often talk about performing a study or conducting an investigation.
  • The articles often contain a methods section or describe how the original research was performed.
  • The focus is often narrower, investigating specific research questions.
  • While most research articles contain a brief literature review in their introduction, it is not the primary purpose of the paper.

Review Articles

Review articles, sometimes called literature reviews or secondary sources, synthesize or analyze research already conducted in primary sources. They generally summarize the current state of research on a given topic. Review articles can help give you a better understanding of the existing research on a topic, identify research questions you would like to explore, and find relevant sources. Review articles often:

  • Summarize key research findings
  • Reference must-read articles
  • Describe current areas of agreement as well as controversies and debates
  • Point out gaps in knowledge and unanswered questions
  • Suggest directions for future research


Identifying Review Articles

In review articles:

  • The abstracts often talk about summarizing existing evidence.
  • The articles often do not include a methods section.
  • The focus is often on summarizing and analyzing a broad set of questions related to a research area.

Gray Literature

Gray literature is research that is either unpublished or has been published in noncommercial forms.

Examples of gray literature include:

  • Government reports
  • Conference proceedings
  • Geological and geophysical surveys
  • Newsletters and bulletins
Advantages of Gray Literature
  • Timeliness: Results of studies may appear in gray literature 12 to 18 months before being published via traditional channels.
  • Flexibility: Rather than waiting years for the publication of a revised edition, authors, editors, and web content creators can update information when needed.
  • Accessibility: There is a great abundance of gray literature that is freely available, either in print or on the web.