Geological Society of America Citation Style

Although GSA doesn’t have a complete style guide (such as the APA or MLA), the GSA website does provide
instructions to authors regarding citations. See the bottom of this website:
In-text citations:
Thoughts, concepts, images, data, graphs and any other information not our own or “common knowledge” are
referenced with direct or parenthetical citations of author and year of publication. Direct quotations are rarely
used, and the in-text citation includes the page number in the original work. For example:
In 1889, Howard Cleary demonstrated for the first time that water not only seeks its own
level, it tries to go even lower than that. Madison (1897) made the observation that ice is
a form of water that does not apparently seek its own level, although it does upon
melting. Chalmers (1899, p. 53) replied, “There is little I can do to stop this nonsense.”
The controversy continues to this day, even in places as remote as Australia,
Newfoundland and western Pennsylvania (Hackett and Smith, 1978; Cleary, 1889).
Each author referred to above should be listed in the References Cited. Every citation in the text must be
included in the References Cited, and every citation listed there must be referred to in the text.
Sources with two authors: (Smith and Jones, 2012)
Three or more authors: (Smith et al., 2013) Note that all authors are listed in the references.
References Cited:
Journal Articles
• Only use author initials, not full first and middle names
• The only capitalized words in the article title are the first word, the first word after a colon, and proper
• All major words are capitalized for the journal title
• Nothing is italicized or underlined.
• Only include a DOI if one is available: DOI may not be available for older articles
Author, F.M., year, Title of article: Title of Journal, v. #, p. ##-##. doi: 10.####/
Kominz, M.A., Browning, J.V., Miller, K.G., Sugarman, P.J., Mizintseva, S., and Scotese, C.R., 2008, Late
Cretaceous to Miocene sea-level estimates from the New Jersey and Delaware coastal plain coreholes:
An error analysis: Basin Research, v. 20, p. 211–226, doi: 10.1111/j.1365-2117.2008.00354.x.
Doglioni, C., 1994, Foredeeps versus subduction zones: Geology, v. 22, p. 271–274.
Walter, L.M., Bischof, S.A., Patterson, W.P., and Lyons, T.L., 1993, Dissolution and recrystallization in
modern shelf carbonates: Evidence from pore water and solid phase chemistry: Royal Society of London
Philosophical Transactions, ser. A, v. 344, p. 27–36.
Conference Abstracts
Published abstract collections (Mostly GSA, AGU, Goldschmidt, etc.):
Lastname, F.M., year, Title of abstract: Abstract collection name, v. #, p. ###.
Sammis, C.G., 1993, Relating fault stability to fault zone structure: Geological Society of America Abstracts
with Programs, v. 25, no. 6, p. A115–A116.
LeMasurier, W.E., and Landis, C.A., 1991, Plume related uplift measured by fault displacement of the West
Antarctic erosion surface, Marie Byrd Land [abs.]: Eos (Transactions, American Geophysical Union), v.
72, p. 501.
Other conference abstracts:
Lastname, F.M., year, Title of abstract: Name of Conference. City, State, Abstracts, v. #, p. ###.
Baker, V.R., 1991, Ancient oceans on Mars: American Astronomical Society Division of Planetary Sciences,
23rd Annual Meeting, Palo Alto, California, Abstracts, p. 99.
Fitzgerald, P.G., 1989, Uplift and formation of the Transantarctic Mountains: Applications of apatite fission
track analysis to tectonic problems: International Geological Congress, 28th, Washington, D.C.,
Abstracts, v. 1, p. 491.
Paper in a Government or University Serial Publication
This covers USGS reports, state geological survey reports, etc. A volume number is not always available.
Lastname, F.M., year, Title of paper: Name of Source, v. #, p. ##-##.
Hay, R.L., 1963, Stratigraphy and zeolitic diagenesis of the John Day Formation of Oregon: University of
California Publications in Geological Sciences, v. 42, p. 199–262.
Yager, R.M., 1993, Estimation of hydraulic conductivity of a riverbed and aquifer system on the Susquehanna
River in Broome County, New York: U.S. Geological Survey Water-Supply Paper 2387, 49 p.
Use this format for books in which the authors are responsible for the entire book. For books in which each
chapter has a different author, use the format below for “Paper or Chapter in a multi-author Book.”
Books published in major cities (New York, Chicago, London, Tokyo, etc.) often leave out the state or country.
Author, F.M., year, Title of book: City, State, Publisher, ### p.
(### p. = total number of pages in the book)
Twiss, R.J., and Moores, E.M., 1992, Structural geology: New York, W. H. Freeman and Company, 532 p.
Books in a series:
In a series, each book has a separate title and author, but they are published as a group (sometimes over a
number of years) and are often given volume numbers. Include the series name and volume number after the
Author, F.M., year, Title of book: City, State, Publisher, Series Title, v. #, ### p.
Vogt, P., and Tucholke, B., editors, 1986, The western North Atlantic region: Boulder, Colorado, Geological
Society of America, Geology of North America, v. M, 696 p.
Weaver, C.E., 1989, Clays, muds and shales: Amsterdam, Elsevier, Developments in Sedimentology, v. 44, 819
Paper or Chapter in a Multi-author Book
This includes articles from GSA and British Geological Society “Special Papers,” as well as articles from the
“Reviews in Mineralogy and Geochemistry” series.
Author, F.M., year, Paper name, in Author, F,M., ed., Title of book, Volume #: PubCity, State, Publisher, ### p.
doi: 10.####/
Carpenter, F.M., 1992, Superclass Hexapoda, in Kaesler, R.L., ed., Treatise on invertebrate paleontology, Part
R, Arthropoda 4, Volume 3: Boulder, Colorado, Geological Society of America (and University of
Kansas Press), 277 p.
LeCain, R., Clyde, W.C., Wilson, G.W., and Riedel, J., 2014, Magnetostratigraphy of the Hell Creek and lower
Fort Union Formations in northeastern Montana, in Wilson, G.P., Clemens, W.A., Horner, J.R., and
Hartman, J.H., eds., Through the End of the Cretaceous in the Type Locality of the Hell Creek
Formation in Montana and Adjacent Areas: Geological Society of America Special Paper 503, p. 137-

  1. doi: 10.1130/2014.2503(05)
    Sawyer, D.S., Buffler, R.T., and Pilger, R.H., 1991, The crust under the Gulf of Mexico basin, in Salvador, A.,
    ed., The Gulf of Mexico Basin: Boulder, Colorado, Geological Society of America, Geology of North
    America, v. J, p. 53–72.
    Taylor, J.C.M., 1990, Upper Permian-Zechstein, in Glennie, K.W., ed., Introduction to the petroleum geology
    of the North Sea (third edition): Oxford, United Kingdom, Blackwell, p. 153–190.
    Fieldtrip Guidebook
    You can cite an entire guidebook, or a guidebook chapter. If citing an entire guidebook, use the format for a
    book. Include a DOI if one is available.
    Author, F.M., year, Name of guidebook chapter, in Guidebook name: City, State, Publisher, ### p. doi:
    Barton, C.C., and Hsieh, P.A., 1989, Physical and hydrologic-flow properties of fractures, in International
    Geological Congress, 28th, Field Trip Guidebook T385: Washington, D.C., American Geophysical
    Union, 36 p.
    Blackstone, D.L., Jr., 1990, Rocky Mountain foreland exemplified by the Owl Creek Mountains, Bridger Range
    and Casper Arch, central Wyoming, in Specht, R., ed., Wyoming sedimentation and tectonics: Casper,
    Wyoming Geological Association, 41st Annual Field Conference, Guidebook, p. 151–166.
    Proceedings from a Symposium or Conference
    Proceedings are long-form articles based on presentations at a conference. Conference abstracts are brief
    summaries of presentations.
    Author, F.M., year, Title of paper, in Title of Proceedings: City, State, Publisher, p. ## to ##. doi: 10.####/####
    Baar, C., 1972, Creep measured in deep potash mines vs. theoretical predictions, in Proceedings, Canadian
    Rock Mechanics Symposium, 7th, Edmonton: Ottawa, Canada Department of Energy, Mines and
    Resources, p. 23–77.
    MacLeod, N.S., Walker, G.W., and McKee, E.H., 1976, Geothermal significance of eastward increase in age of
    upper Cenozoic rhyolitic domes in southeastern Oregon, in Proceedings, Second United Nations
    Symposium on the Development and Use of Geothermal Resources, San Francisco, May 1975, Volume
    1: Washington, D.C., U.S. Government Printing Office (Lawrence Berkeley Laboratory, University of
    California), p. 465–474.
    Theses and Dissertations
    Author, F.M., year, Title of thesis [Ph.D. thesis]: School Name, ### p. doi: 10.####/####
    Wopat, M.A., 1990, Quaternary alkaline volcanism and tectonics in the Mexican Volcanic Belt near Tequila,
    Jalisco, southwestern Mexico [Ph.D. thesis]: Berkeley, University of California, 277 p.
    Author, F.M., year, Webpage title: URL (accessed Month Year).
    Advanced National Seismic System, 2007, ANSS global earthquake catalog: (accessed November 2007).
    Scotese, C.R., 2003, PALEOMAP Project: (accessed August 2011).

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