GSA Style Guide

GSA Style was developed by the Geological Society of America and is a standard citation style used in the field of geology.

Two types of citations are included in most research papers: citations within the text of the document and a list of reference citations at the end of the paper.

• In-Text Citations: GSA Style uses the author-date citation system for in-text citations, similar to APA Style.
• Reference Citations: The sources you use in your work are included as a separate list at the end of the paper. GSA Style suggests using the title, References Cited, for the list.

About GSA Style

This guide is a quick introduction to the Geological Society of America Style for references and citations.

Be sure to consult the GSA website for detailed standards and procedures:

GSA Author Guidelines

The page on Preparation and Submission of Manuscripts provides guidelines to GSA Style, including the following documents:

This PDF document from the GSA website is the authority on the citation style preferred for their publications. You may be asked by your geology instructor to use the same style for your research.

Using figures in your work? All illustrations, whether line drawings or photographs are considered figures in GSA Style.

In-text Citations

When you reference another source, use an in-text citation in the body of your paper.

Basic Format:

(Author's Last Name(s) or Organization, Year).

I'm using.

Direct Quotes

If you're quoting the exact words of someone else, introduce the quote with an in-text citation in parentheses. Any sentence punctuation goes after the closing parenthesis.

• According to Brown (2019), "Direct quote" (p. 1021).
• Brown (2019) found that "Direct quote" (p. 1021).
• [Some other introduction] "Direct quote" (Brown, 2019, p. 1021).

If you're directly quoting more than 40 words, use a blockquote. Block quotes don't need quotation marks. Instead, indent the text 1/2" as a visual cue that you are citing. The in-text citation in parentheses goes after the punctuation of the quote.

Shavers (2007) study found the following:

While research studies have established that socioeconomic status influences disease incidence, severity and access to healthcare, there has been relatively less study of the specific manner in which low SES influences receipt of quality care and consequent morbidity and mortality among patients with similar disease characteristics, particularly among those who have gained access to the healthcare system. (p. 1021)

Tip: Use direct quotes sparingly! Focus on summarizing the findings from multiple research studies. In the sciences and social sciences, only use the exact phrasing or argument of an individual when necessary.

Summarizing or Paraphrasing

Paraphrasing or summarizing the main findings or takeaways from a research article is the preferred method of citing sources in an APA paper. Always include the last name of the author(s) and the year of the article, so your reader can find the full citation in the reference list.

According to Shavers (2007), limitations of studying socioeconomic status in research on health disparities include difficulties in collecting data on socioeconomic status and the complications of classifying women, children, and employment status.

I'm citing.

One Author

You only need the author's last name and the year.