KGS Style Manual and Word Usage Guide

This style manual and word usage guide is designed to provide guidance to editors, authors, proofreaders, graphic artists, and cartography personnel. Using a style manual ensures quality, clarity, and consistency in our publications. Other style manuals recommended to supplement this are the USGS Suggestions to Authors, the Government Printing Office Style Manual, Strunk and White's The Elements of Style, and The Chicago Manual of Style.

The KGS style is preferable for in-house publications; however, it is flexible and an author's preferences will be considered so long as accepted grammatical rules are followed and consistency is maintained. If you have any questions concerning style, grammar, or word usage, please contact the KGS editor at

KGS Publications Program

KGS Online Bibliography of Geology

The KGS maintains an online bibliography of publications on topics related to Kansas geology, including KGS publications. You may search the bibliography by topic, keyword, author, and more.

KGS Online Bibliography of Geology

KGS Style Guide and Word Usage Manual

  1. Leave no space after one-letter abbreviations, except for author's names:
    • e.g.
    • n.sp.
    • nov. sp.
    • W. A. Black
    • U.S.
  2. Spell out all state names in text and references.
  3. Spell out United States if used as a noun; you may abbreviate it when it is used as an adjective:
    • The United States relies on the Middle East for most of its oil.
    • Middle East and U.S. oil production fell in 1991.
  4. Note that some abbreviations are acceptable in maps and charts only. Some abbreviations have periods; others do not. In general, if an abbreviation might be confused with a word, use a period. See the list of commonly used abbreviations (below) or USGS Suggestions to Authors for guidance.
  5. Always spell out an abbreviation of a term or phrase the first time it is used. Use the abbreviation for all instances of the term subsequently.
    • The American Chemical Society (ACS) publishes many journals.
    • Subscriptions can be ordered by contacting the ACS.
  6. Use articles (a, an, the) with abbreviations unless the abbreviation is normally pronounced as a word:
    • The EPA has issued new regulations. OSHA has also released its new regulations.
  7. In general, abbreviations of standard units do not have to be defined unless they are created units or nonstandard. Abbreviations should be the accepted SI units (with the exception of “s” for seconds; the KGS uses “sec”).
  8. Spell out compass directions in text; abbreviate in township and range descriptions.
    • The outcrop is located in the northwest corner of sec. 4.
    • The outcrop is located in NW sec. 4, T. 22 S., R. 12 E.

See also List of Abbreviations below.

  1. Do not capitalize the terms "aquifer," "aquifer system," "zone," and "confining unit":
    • Ogallala aquifer
  2. Do not capitalize or hyphenate such terms as "sand and gravel aquifer" and "limestone aquifer."
  3. Do not capitalize adjective modifiers, except parts of formal geologic names:
    • Mississippi River alluvial aquifer
  4. Do not capitalize relative-position terms (upper, middle, lower). They may be capitalized, however, if they represent parts of a regional aquifer system that are separated by a major confining unit:
    • upper Ogallala aquifer
    • Upper Floridan aquifer system, Lower Floridan aquifer system
  5. Use quotation marks only when the aquifer name is a misnomer:
    • "500-ft" sand
  6. Clearly distinguish hydrologic and geologic names:
    • Wells completed in Madison Limestone (not Madison wells)
    • Water from the Madison aquifer (not Madison water)
  7. Hierarchy of terms for largest (regional) to smallest (local) water-yielding units: aquifer system, aquifer, zone. Units that bound the aquifer are called confining units (not confining beds).
  8. Aquifer names should be derived from one of the following sources: rock-stratigraphic terms (e.g., Sparta aquifer), lithology (e.g., limestone aquifer), geographic features (e.g., High Plains aquifer).
  9. Aquifer names should not be derived from the following sources: time-stratigraphic terms (e.g., Cretaceous aquifer), relative position (e.g., upper carbonate aquifer), alphanumeric designations for model layers or acronyms (e.g., A1 aquifer layer), depositional environment (glacial aquifer), depth of occurrence ("500-ft" sand), hydrologic condition (e.g., water-table aquifer).
  1. In general, capitalize geographic terms and use lowercase for geologic terms:
    • Flint Hills
    • Hugoton embayment
  2. Capitalize the words "state," "federal," and "county" only when used with proper names:
    • Douglas County, the county
    • Douglas and Jefferson counties (note lowercase when plural)
    • U.S. Federal Reserve
    • federal government, state government
  3. Capitalize "valley" as part of a proper name except when used with a river name:
    • Smoky Hill River valley
    • Smoky Hill Valley
  4. Capitalize officially recognized stratigraphic units.
  5. For the following terms, lowercase is preferable even when used with a proper name; however, this can be left to the discretion of the author so long as consistency is maintained:
    • anticline
    • arch
    • area
    • basalt flow
    • basin
    • batholith
    • caldera
    • cauldron
    • claim
    • coal bed
    • coal field
    • coal seam
    • cone
    • cyclothem
    • deposit
    • dome
    • embayment
    • escarpment
    • facies
    • fault
    • fault zone
    • homocline
    • mill
    • mine
    • mining district
    • monocline
    • oil field
    • pluton
    • principal meridian
    • prospect
    • quadrangle
    • region
    • rift
    • sag
    • syncline
    • uplift
    • well
    • zone
  6. Capitalize geologic-time divisions according to the USGS Suggestions to Authors.
  1. Chemical names, rather than symbols, are generally used except in long lists:
    • Analysis showed the presence of magnesium and calcium.
    • Analysis showed the presence of Mg, Sb, Rb, Pt, Ag, and Au.
  2. Spell out names of elements or compounds unless the terms are complex (note use of hyphens):
    • sodium chloride solution
    • Ca-Mg-SO3-NO3 solution
  3. Use symbols instead of the spelled out chemical name when several terms are used in close proximity:
    • Ca+ and Mg+ ions combine with CO3- and SO4-, respectively.
  4. Place the mass number of an isotope to the left (and as a superscript) to the element:
    • 14C
    • 85Rb (but in ratios, the mass number can go on the right: Rb85/Rb87)
    In publications written for a nonprofessional audience, the mass number still appears on the left. In such publications, the following usages are acceptable:
    • carbon 14; C-14
    • uranium 238; U-238
  5. Use a numeral followed by the plus or minus sign for valences:
    • Fe2+
    • Fe3+
    • N3-
    • Cl-
    In text discussions, the order of number and sign are reversed (e.g., a charge of +2; a -1 charge).
  6. Set abbreviations for phase states in lowercase italic and place in parentheses:
    • aq—aqueous
    • s—solid
    • g—gas
    • l—liquid
    • c—macrocrystalline
    • NiS(s) + O2(g) —> NiO(s) + SO2(g)
  7. Italicize units of chemical concentration: molar (M), molal (m), normal (N).
  8. Set oxidation numbers as roman numerals in parentheses immediately after the name or symbol of the element:
    • iron(II) chloride
    • Cu(III)

Words always used as two words; these words are hyphenated when used as unit modifiers except for -ly words, which are never hyphenated (ash-flow tuff, poorly sorted unit):

  • air fall
  • ash flow
  • cliff former
  • coal bed
  • coal field
  • cross section (always two words)
  • dip slip
  • drill hole
  • field work
  • open pit (noun)
  • plane table (noun)
  • poorly sorted
  • red beds
  • road beds
  • sea floor
  • slope former
  • spring water
  • strip mine
  • strip mining
  • surface water (noun)
  • turn out (verb)
  • water table
  • year end

Words always used as one word:

  • airview
  • backslope
  • bandwidth
  • beachrock
  • bedrock
  • borehole
  • crossbed (all forms)
  • crosscut (all forms)
  • damsite
  • database
  • downdip (noun)
  • downgradient
  • downhole
  • downslope
  • downstream
  • drawdown
  • dumbbell
  • floodplain
  • footslope
  • freshwater
  • groundwater
  • hillslope
  • landform
  • metaquartzite (rock type)
  • midcontinent
  • mudflow
  • nearshore
  • orebody
  • roadcut
  • rockcut
  • saltwater
  • seawater
  • shoreface
  • shoreline
  • sideslope
  • sinkhole
  • standstill
  • strandline
  • streambank
  • streamflow
  • toeslope
  • turnout (noun)
  • twofold, etc.
  • updip (verb)
  • upgradient
  • upsection
  • upslope
  • watershed
  • website
  • windblown

Words always used with a hyphen:

  • cross-lamination
  • meta-quartz (mineral)
  • cross-stratification
  • post-tectonic

Preferred KGS spellings:

  • anisotropy, anisotropic
  • email
  • isotropy, isotropic
  • limy
  • minable
  • overlie
  • shaly
  • sizable
  • totaled
  • traveled
  • underlie
  • usable
  • volcanoes

See AGI's Glossary of Geology for additional guidance

  1. Set names of computer languages that can be read as words with an initial capital and lowercase letters:
    • Fortran
    • Basic
    • Algol
    • Cobol
  2. Capitalize names of computer languages that cannot be read as words. If the name is long, consider using small caps to improve readability and to save space:
    • APL
    • PL/1
    • RPG
  3. Set names of computers, if pronounceable, with initial cap and lowercase letters; otherwise, set them in all caps (or small caps):
    • Edvac
    • Univac
    • Xerox
    • Sigma
    • Intel 4004
    • XGP
  4. Set names of computer programs, subprograms, routines, algorithms, and statements in all caps or small caps:
    • algorithm ENTER
    • PRINT statement
    • EDIT facility
  5. Set instructions to the computer in cap and lowercase:
    • Save As
    • Add to Menu
    • Store in Memory
    • Write
  1. In general, the KGS follows the International Geological Time Scale defined by the International Commission on Stratigraphy.
  2. The name Precambrian is informal and without specific stratigraphic rank.
  3. Capitalize such modifiers as lower, middle, and upper only when they are formally recognized divisions of geologic time. Informal divisions should be lowercase:
    • Lower Cretaceous
    • middle Precambrian
    • early Mesozoic
  4. Distinguish carefully between terms of time (geochronologic, geochronometric) and position (chronostratigraphic), especially in discussions of layered rock.
    • the Early Cambrian trilobites
    • the specimen is from the Lower Cambrian shales of…
  1. Use m.y. and k.y. (million years and thousand years, respectively) for durations and as a unit:
    • The average period of the precession index is 20 k.y.
    • The main obliquity term is 23 k.y.
  2. Use Ma and ka (million years ago and thousand years ago, respectively) for dates before the present time:
    • The values of the orbital peaks are those predicted for 200 Ma.
    • The main obliquity term was 47 k.y. at 200 Ma.
  1. Do not italicize the terms "log," "ln," "sin," "cos," "tan," etc. in mathematical expressions or in text.
  2. Do italicize all other mathematical (and statistical) symbols in text and in displayed material except for vectors and tensors (which are set in boldface and roman).
  3. For paleontological terms, italicize genus and species names, not family or order:
    • …in the family Prosopidae, the species Prosopon tuberosum
  4. Italicize the name of a book or journal in text but not in reference list.
  5. Do not italicize common foreign terms, such as en echelon and in situ.
  1. Number all displayed equations in text, even if they aren't referred to in the text.
  2. Refer to equations by number: Eq. (1). Use "inequality" or "expression" or some other identifier for math that is not an equality.
  3. Punctuate all equations as you would a sentence:
    •                         If the inequality                         x > y                                     (1)
    •                         holds, then                                a = b.                                    (2)
  4. Place equation numbers flush right.
  5. If several expressions are related, they may be numbered with a number and a letter:
    •                         x > y,                                                                                  (1a)
    •                         y > z,                                                                                  (1b)
    •                         x > z.                                                                                   (1c)
  6. Authors should identify special symbols used in math expressions so that they can be properly formatted when the time comes.
  7. Italicize all mathematical symbols in the Roman alphabet, unless (1) they represent vectors or tensors (which are set in bold roman), (2) they are abbreviations (or the whole word) for some nonmathematical identifier (e.g., "tot" for "total"), (3) they are units of measure, or (4) they are mathematical functions (e.g., log, ln, sin, lim, exp).
  8. Do not use "loge" for "ln." Do not use "log10" for "log."
  9. In text and displayed equations, it is permissible to use "exp" in place of e. Complicated expressions are best set in the "exp" form:
    • exp(xyz2 - 4sf)
    • exyz or exp(xyz)
  1. For a measurement, use a numeral:
    • 1 ft
    • 12 ft
    • 2 mi
    • 10 km
  2. Use numerals for time periods:
    • 3 b.y.
    • 3 days
    • 10 yr
    • 2 hr
    • 10:00 a.m.
  3. For strike and dip, use numerals:
    • dips 10° westward
    • 65°–70° N
    • strike N 30° E
  4. On other items, use a numeral for 10 or above; write out below 10:
    • 12 books
    • three books
  5. Dates may read October 20, 1986, or 20 October 1986 so long as consistency is maintained (KGS preferred style is October 20, 1986). Do not use apostrophes in dates: 1980s.
  6. For ranges of dates, use all four digits:
    • 1890–1927
    • 1934–1937
  7. In intervals, use an en dash (option-hyphen on Mac), except when following the word "from" (then use "to"):
    • 10–20 ft thick
    • from 10 to 20 ft thick
  8. Spell out numbers at the beginning of a sentence:
    • Eighty percent of the samples were destroyed.
  9. When a number less than 100 precedes a unit modifier, spell it out:
    • four 2-in. pipes
    • 400 2-in. pipes
  10. Always put a zero in front of a decimal point: 0.25, not .25
  11. Spell out fractions that stand alone:
    • The dike was one-third the width of the outcrop.
  12. When a fraction is used with a whole number or in a unit modifier, use figures:
    • 1 1/2 mile
    • 3.5 km
    • ½ in. pipe
    • 0.5 in. spacing
  13. Pay attention to significant figures in giving measurements and in rounding off numbers. USGS Suggestions to Authors has a good explanation of the use of significant figures. Significant figures are particularly important in converting metric units to English units and vice versa.
  14. Avoid expressions such as the following:
    • from 14 ft thick up to at least 30 ft thick (if 30 ft is the upper limit, then there is no need for "at least"; if 30 ft is not the upper limit, as indicated by the "at least," then state the true upper limit)
    • approximately 13.41 in. (the significant figures after the decimal indicate that this is not an approximation)
  15. Use figures for numbers used as nouns:
    • the number 3.14159
    • a factor of 4
    • approaches 0
  16. Use figures in other designations:
    • item 3 in the list
    • method 2
    • type 3
  17. In tables, align columns of numbers on the decimal point.
  18. Treat numbers in related expressions in the same style:
    • Enrollment records showed 9 geology students, 15 geophysics students, and 11 astronomy students in the School of Geology.
  19. Unconnected numerical expressions follow the figure vs. spelled-out rule applicable for that number:
    • The number of rocks in the collection grew from 430 to 690 in five years.


  1. Use periods for points of ellipsis (or use option-semicolon on a Mac).
  2. Use periods at the end of captions and, obviously, at the end of a sentence.
  3. Do not use periods at the end of titles or at the end of headings.
  4. Refer to the abbreviations list for guidance on when to use periods in abbreviations. In general, periods are not used with units of measure.
  5. Use a period after the number in vertical lists.
  6. In lists, use a period at the end of each item if each item is a complete sentence. Do not use a period if the items in the list are phrases or incomplete sentences. Use a period after each item in a list if the items are mixed (sentence and nonsentence).
    • We will do the following in this laboratory:
      1. Each lab group will collect specimens.
      2. Each group will prepare its own thin sections.
      3. One group will prepare powdered specimens for neutron activation analysis.
    • The following accessory minerals were observed in thin section:
      • sphene
      • zircon
      • magnetite
    • There are three main groups of rocks:
      • Igneous: Not exposed in Kansas.
      • Sedimentary: Widely exposed in Kansas. These rocks can be collected at many road cuts.
      • Metamorphic: Not exposed in Kansas.
  7. Place periods inside quotation marks. Place them inside or outside parentheses and brackets depending on meaning.
    • Smith used the term "meta-quartz."
    • The lab technician insisted on reanalyzing the data. (The professor had encountered this intransigence before.)
    • He reanalyzed the data (although the professor had asked him not to).
  8. Use periods after the table or figure  number in table and figure captions.
    • Table 1. Number of wells that draw all or part of their yield from the Dakota aquifer.
    • Figure 2. Mississippian nomenclature changes to Zeller (1968) that are formally adopted by the KGS.


  1. Use a comma before the last item in a series:
    • a, b, and c.
  2. Use a comma in numbers of four or more digits:
    • 1,432
    • 10,286
  3. Use commas in dates as follows:
    • September 10, 1981, to April 3, 1982, was the first…
    • April 1975 (no comma between April and 1975)
  4. Place commas inside quotation marks.
  5. Use a comma to separate two independent clauses joined by a coordinating conjunction:
    • Smith collected igneous rocks, and Jones collected metamorphic ones.
  6. If a dependent clause precedes the second independent clause, no comma is needed after the conjunction:
    • The situation is perilous, but if we are prepared to act promptly, there is still one chance of escape.
  7. Do not use a comma in sentences with a compound predicate (two verbs having the same subject):
    • Smith collected the rocks and analyzed them at the museum.
  8. Use a comma to set off a dependent clause that precedes the main clause:
    • If you collect the rocks, I will analyze them.
  9. Use a comma to set off an introductory participial phrase:
    • By comparing the samples, we will determine any trends in composition.
  10. Use a comma after such expressions as "that is," "for example," "i.e.," and "e.g."
  11. Use commas between two or more adjectives of equal rank that precede the word they modify (if adjectives are parallel, you will be able to insert "and" between them and reverse the order with no change in meaning):
    • hard, impermeable subsoil
    • red, fine-grained, subrounded sand particles
    • strong lateral ground motion

Quotation marks

  1. Use quotation marks only for directly quoted material:
    • The term he used was "red beds" (Smith, 1974, p. 37).
    • Aquifers are defined as "rock or sediment formations that have a sufficiently large number of interconnected pores to contain usable amounts of extractable water" (Buddemeier et al., 1991, p. 1).
  2. Place periods and commas inside quotation marks; question marks and exclamation points inside or outside depending on meaning; and colons and semicolons outside.
  3. If you are using quotation marks around a stratigraphic name to indicate abandonment of the name or a misapplication, explain your usage in the text so that readers will not be confused.
  4. Use quotation marks to indicate words or phrases used as terms:
    • The term "silt" refers to unconsolidated rock particles finer than sand and coarser than clay.
  5. Do not use quotation marks after "so-called":
    • The so-called infraction of rules was just a misunderstanding.
  6. Do not use quotation marks to indicate that you know that a particular word isn't quite right. Find the appropriate word and use it.


  1. Use a colon after an introductory statement to convey that something is to follow:
    • We will cover the following subjects: petrology and petrography.
  2. Use a colon to separate two independent clauses, the second of which amplifies the first (a semicolon or a dash could serve the same purpose):
    • Contact relations indicate that the granodiorite was the last intrusive phase: it cuts the diorite and tonalite.
  3. Use a colon to introduce long quotations, especially block quotations (those set off from regular text as a separate paragraph).


  1. Use a semicolon to separate the parts of a compound sentence when a conjunction is not used:
    • Smith collected the rocks in the spring; he did not analyze them until the following winter.
  2. Use a semicolon to separate items in a series if the items are long or complex or have internal punctuation:
    • The rocks included a sandstone, which was fine-grained and stained with iron; a basalt, which was partially altered by hydrothermal solutions; and a slate, which was slickensided.

Question marks

  1. Use a question mark at the end of an interrogative:
    • Who analyzed the data?
  2. Do not use a question mark with an indirect question:
    • She wondered why the data had been reanalyzed.
  3. Place question marks inside or outside quotation marks, parentheses, and brackets depending on the meaning:
    • She asked, "Who reanalyzed the data?"
    • Why was the professor angry when she said, "I'm here to find out who reanalyzed the data"?
    • The meeting is delayed until the professor returns from vacation (March 18?).
  4. Use question marks to indicate uncertainty in stratigraphic or paleontologic designations:
    • The Hepler sandstone (?) crops out over there.
    • Spirifer ? grimesi Hall
    • ?Spirifer grimesi Hall


  1. Submit manuscripts without end-of-line hyphenation—that is, use left-justified formatting, not full justification.
  2. Use hyphens in unit modifiers as described below.
    • Use hyphens in adjectives modifying nouns, when the unit modifier precedes the noun:
      • a fine-grained sandstone
      • heat-flow data
    • Do not use hyphens with -ly adverbs:
      • a poorly sorted collection
    • Do not use hyphens with three-word modifiers that begin with two adverbs:
      • very fine grained sandstone (note, however, that generally in text, the use of "very" is discouraged because of its subjective nature)
    • Do not use hyphens for predicate adjectives, or in general when an adjective follows the verb:
      • sandstone is fine grained
    • Do not use hyphens with abbreviations in unit modifiers:
      • 3 ft thick sequence
      • 25 ft (7.6 m) thick deposit
    • Do not use hyphens with foreign phrases used as unit modifiers:
      • in situ mining
      • en echelon faults
    • Do not use a hyphen if the words of the unit modifier commonly go together:
      • rare earth elements
      • solid waste disposal
    • Examples of hyphen use in stratigraphic section descriptions:
      • limestone, light-olive-gray, medium-crystalline (adjectives all read back to noun)
      • very fine to fine-grained sandstone
      • fine- to medium-grained sandstone
    • Miscellaneous unit-modifier examples:
      • pale-red outcrops
      • reddish to brownish mudstone
      • pale-red-grayish rock
      • east-central Kansas
      • very dark gray shale
  3. Use a hyphen (not an en dash) to join proper names if both names are one word:
    • Cambrian-Ordovician
  4. In most cases, do not use a hyphen between a prefix or a suffix and the word it modifies:
    • nonmetric
    • unexposed
    • tenfold
    • but quasi-official, non-quartz-bearing rock
  5. Insert a hyphen between a prefix or a suffix and the word it modifies if the consonant would be tripled or the vowel would be doubled:
    • bell-like
    • electro-optic
  6. Use a hyphen to prevent mispronunciation or to avoid ambiguity:
    • un-ionized (as distinguished from unionized)
    • re-present (as distinguished from represent)
  7. Do not use a hyphen in chemical compounds:
    • carbon dioxide
    • sulfuric acid
  8. Use hyphens to separate numbers that are not inclusive ranges, such as phone numbers and zip codes:
    • (785) 864-3965
    • 66045-1291

En dashes

  1. An en dash is half the length of an em dash and longer than a hyphen (on a Mac, type option-hyphen to get an en dash). Use an en dash in ranges of time, dates, or numbers:
    • 1968–1982
    • p. 83–147
    • 13 May 1934–9 June 1940
  2. Use the en dash to join proper names when one (or both) of them is more than one word:
    • Topeka–Kansas City corridor
  3. Use an en dash in place of a hyphen with prefixes to compound adjectives:
    • post–World War II period
  4. Use an en dash instead of a hyphen between two hyphenated compound adjectives:
    • quasi-public–quasi-judicial body

Em dashes

  1. An em dash is the standard dash in punctuation (on a Mac, type shift-option-hyphen to get an em dash). Use an em dash to punctuate a sudden break in thought or to set off a parenthetical element:
    • The rock specimens — too numerous to list here — are stored in the museum.
    • The sedimentary rock specimens — sandstone, siltstone, and shale — are stored in the museum.

Slash (virgule)

  1. Do not use a slash to mean "and," "or," or other words. Say what you mean so that your reader does not have to guess.
  2. Use a slash to mean "per":
    • m/sec

In-text reference citations

  1. For in-text reference citations, give the author(s) surname and year of publication:
    • Jones, 1978; Smith and Jones, 1967
  2. For a work by more than two authors, use "et al.":
    • Smith et al., 1980 (note: include all authors’ names in the reference list)
  3. For manuscripts accepted for publication but not yet published, follow the same format but specify in the reference list that material is in press:
    • Example: Jones, A., 1992, Kansas rivers; Journal of Geology (in press).
  4. Use a semicolon to separate citations of different authors:
    • Jones, 1989, 1991; Smith, 1991
  5. Cite written communications, personal communications, and unpublished data taken from sources such as field notes in the text only and not in the list of references. In these cases, use the communicator's initials:
    • D. W. Jones, personal communication, 1979
    • R. J. Smith, written communication, 1981
    • P. J. Davidson, unpublished data, 1947
  6. In-text citations may become a problem when there are many papers that have three or more authors in which the first author is the same. List enough information (for example, second author) to distinguish among papers:
    • Jones, Smith et al., 1991; Jones, Brown et al., 1991

Reference list

  1. List authors' names last name first:
    • Jones, A. S., Smith, J. D., Jr.
    • Jones, A. S., Allen, B. D., III
  2. Format titles of articles and chapters in sentence style (initial cap and lowercase; proper nouns capitalized).
  3. Format titles of books as caps and lowercase (main words capitalized).
  4. Spell out all names of publishers and organizations in full.
  5. Style for schools:
    • University of California (Davis), not at Davis
    • University of Texas (Austin), not at Austin
  6. Place citations at end of figure captions in parentheses:
    • Figure 1. Geologic map of Douglas County (after McClain, 1980).

What constitutes a complete reference?

  1. All journal references must have (a) all authors' (or editors') names, (b) year of publication, (c) title of article, (d) title of journal, (e) volume number and issue number (if any), and (f) beginning and ending page numbers of article. DOI numbers, when available, are strongly encouraged.
    • Boellstorff, J. D., 1973, Fission-track ages of Pearlette family ash beds — comment: Geology, v. 2, p. 21.
    • Bushue, L. J., Fehrenbacher, J. B., and Ray, B. W., 1974, Exhumed paleosols and associated modern till soils in western Illinois: Soil Science Society of America, Proceedings, v. 34, p. 665–669.
    • Zipper, S., Farmer, W. H., Brookfield, A., Ajami, H., Reeves, H. W., Wardropper, C. B., Hammond, J. C., Gleeson, T., and Deines, J. M., 2022, Quantifying streamflow depletion from groundwater pumping: A practical review of past and emerging approaches for conjunctive water management: Journal of the American Water Resources Association, v. 58, no. 2, p. 289–312.
  2. All book references must have (a) all authors' (or editors') names, (b) year of publication, (c) title of book, (d) location of publisher (city and state; or city and country if foreign), (e) publisher, and (f) number of pages in book:
    • Fenton, C. L., and Fenton, M. A., 1958, The Fossil Book: Garden City, New York, Doubleday and Company, 482 p.
  3. All theses and dissertation references must have (a) author's name, (b) year of publication or completion, (c) university name, (d) university location (city and state; or city and country if foreign), and (e) number of pages in thesis or dissertation; academic department is optional:
    • Dubins, I. M., 1947, The petrography, geochemistry, and economic utilization of the Fort Hays chalk in Kansas: M.S. thesis, Department of Geology, University of Kansas, Lawrence, 84 p. (Note: State may be omitted from university location if it is part of university name.)
  4. Chapters in a book must have (a) all authors' names, (b) publication date, (c) title of chapter, (d) title of book, (e) editors of book (may be an organization), (f) publisher of book and location, and (g) beginning and ending page numbers of chapter:
    • Cowie, J. W., 1974, The Cambrian of Spitzbergen and Scotland; in Cambrian of the British Isles, Norden, and Spitzbergen, C. H. Holland, ed.: London, John Wiley and Sons, p. 123–155.
  5. Conference papers. In general, avoid citing papers that were presented at a meeting unless there is no published form of the paper. The papers usually are published in conference proceedings. Thus you should cite the conference proceedings as the reference and treat the paper as a chapter in a book. For published proceedings, do not give the title of the meeting and where and when the meeting was held as the publication material. Use the meeting information only if the paper has not been published or if the paper was a poster session.

See the sample references for other types of citations.

Sample references

Chapter, section, or other part of larger publication

  • Johnson, W. C., and Martin, C. W., 1987, Holocene alluvial-stratigraphic studies from Kansas and adjoining states of the east-central Plains; in Quaternary Environments of Kansas, W. C. Johnson, ed.: Kansas Geological Survey, Guidebook Series 5, p. 109–122.


  • Asquith, G. B., Gilbert, J. L., and Smith, R. C., 1976, Fortran IV program for the analysis of sedimentary structures from stratigraphic sections (abstract): Geological Society of America, Abstracts with Programs, v. 8, no. 5, p. 563.


  • Hattin, D. E., 1982, Stratigraphy and depositional environment of Smoky Hill Chalk Member, Niobrara Chalk (Upper Cretaceous), of the type area, western Kansas: Kansas Geological Survey, Bulletin 225, 108 p., 1 sheet.


  • Yarger, H., Robertson, R., Martin, J., Ng, K., Sooby, R., and Wentland, R., 1981, Aeromagnetic map of Kansas: Kansas Geological Survey, Map M-16, scale 1:500,000.


  • Heckel, P. H., 1975, Field guide to Stanton Formation (Upper Pennsylvanian) in southeastern Kansas: Kansas Geological Society, 31st Regional Field Conference Guidebook, p. 2–71.


  • Boellstorff, J. D., 1973, Fission-track ages of Pearlette family ash beds — comment: Geology, v. 2, p. 21.
  • Bushue, L. J., Fehrenbacher, J. B., and Ray, B. W., 1974, Exhumed paleosols and associated modern till soils in western Illinois: Soil Science Society of America, Proceedings, v. 34, p. 665–669.

Open-File Report

  • Whittemore, D. O., 1984, Initial report on the geochemical identification of the source of salinity in ground waters in northwestern Harvey County: Kansas Geological Survey, Open-File Report 84-6 (a report for Equus beds Groundwater Management District #2), 11 p.


  • Chang, J., 1965, On some Lower Ordovician nautiloids from Qilianshan, northwestern China: Acta Palaeontologica Sinica, v. 13, no. 2, p. 43–362 (in Chinese, with English summary).
  • Maat, P., and Johnson, W. C., 1996, Thermoluminescence and new C-14 age estimates for late Quaternary loesses in southwestern Nebraska: Geomorphology (in press).
  • Lam, C., and Yarger, H. L., [n.d.], State gravity map of Kansas; in Geophysics in Kansas — 25-yr Update, D. W. Steeples, ed.: Kansas Geological Survey, Bulletin 226. [use this style when publication date can't be determined].

Alphabetizing the reference list

  1. In general, alphabetize the entire reference list by the last name of the first author.
  2. If two or more authors have the same last name, alphabetize them by their initials:
    • Jones, A. S.
    • Jones, A. W.
    • Jones, R. T.
  3. All single-author entries precede multiple-author entries for that senior author. For multi-author entries, consider each group of authors as one unit, regardless of the number of co-authors. For each senior author, alphabetize multi-author entries by second author; if the first two authors are identical, alphabetize by third (and so on). Examples:
    • Jones, A. S.
    • Jones, A. S., and Brown, N. R.
    • Jones, A. S., and Brown, W. T.
    • Jones, A. S., Brown, W. T., and Smith, M. A.
    • Jones, A. S., and Carlton, D. E.
    • Jones, A. S., Harper, M. S., Carlton, D. E., and Smith, M. A.
    • Jones, A. S., Smith, M. A., and Carlton, D. E.
    • Jones, A. S., Smith, M. A., Carlton, D. E., and Harper, M. S.
  4. When authors are the same, list in chronological order from oldest paper to most recent paper:
    • Jones, A. S., and Brown, W. T., 1987
    • Jones, A. S., and Brown, W. T., 1990
    • Jones, A. S., and Brown, W. T., 1991
  5. If two or more references have the same authors and dates, add a letter to the publication year. If the order of publication is not known (that is, which was published first in a given year), alphabetize by title (ignore the words "a," "an," and "the"):
    • Jones, A. S., 1990a, The igneous rocks of Kansas…
    • Jones, A. S., 1990b, Sedimentary rocks of Kansas…
    • Jones, A. S., 1990c, Water levels in Johnson County…

Note: In taxonomic papers, because of issues of priority, the correct ordering of same-year publications is important. Consult authors for help in determining correct order.

aff.affinityrelated to
auct.auctorumof authors
comb. nov.combinatio novanew combination
emend.emendation; emendedchange in spelling of name
fam. nov.familia novanew family (only after family name)
f. sp.forma specialisspecial form (only after species name)
gen. nov.genus novumnew genus (only after genus name)
inc. sed.incertae sedisuncertain position
m.morphaform (only after species name)
nom. cons.nomen conservandumretained name
nom. dub.nomen dubiumdoubtful name
nom. nov.nomen novumnew name
nom. nud.nomen nuduminvalid name
nom. rej.nomen rejiciendumrejected name
s.l.sensu latobroad sense
sp.; spp.species (singular; plural)(only after genus name)
sp. nov.species novanew species (only after species name)
s.s.sensu strictorestricted sense
ssp.; sspp.subspecies (singular; plural)(only after species name)
ssp. nov.subspecies novanew subspecies (only after subspecies name)
var.varietasvariety (only after species name)
var. nov.varietas novanew variety (only after variety name)


  1. Formal generic and specific fossil names are in Latin and are italicized. Do not italicize informal names and adjectives based on fossil names:
    • foraminiferal, foraminifer
    • spirifer
    • bryozoan
    • mollusk, molluskan (not mollusc, molluscan)
  2. Spell out in full the first use of a genus-species combination. In subsequent references to the same critter or to another species within that genus, the genus can be abbreviated:
    • Atrypa unisulcata, A. unisulcata, A. uniangulata. 
    Be sure that each abbreviation of a genus is unique; for example, don't use "G." to mean both Goniatites and Glyphioceras in the same manuscript. Spell out the genus name in full to avoid confusion.
  3. Certainty of identification of taxa (from USGS Suggestions to Authors):
    • Spirifer grimesi Hall — Taxon definitely identified
    • Spirifer cf. S. grimesi Hall — Taxon compared with named species
    • Spirifer aff. S. grimesi Hall — Taxon has affinities with named species
    • Spirifer ? grimesi Hall — Species questionably assigned to genus
    • Spirifer grimesi Hall? — Species doubtful but assigned to correct genus
    • ?Spirifer grimesi Hall — Entire assignment doubtful
  1. List of undesirable expressions:
    • Permo-Penn (use Permian and Pennsylvanian)
    • Cambro-Ordovician (use Cambrian and Ordovician)
    • Mid-Cambrian (use Middle Cambrian)
    • Westwater Member (use Westwater Canyon Member)
    • hydrofer, aquiformation (use aquifer or aquifer system)
    • aquigroup (use aquifer system)
    • sulphur, sulphide, sulphate (use sulfur, sulfide, sulfate)
    • rare earths (use rare earth elements; a rare earth is an oxide of a rare earth element)
  2. Do not use map symbols in text as a shorthand for formation names; spell out formation names in text.
  1. "Author" is a noun, not a verb. A book is "written by," not "authored by."
  2. Use of "comprise" and "compose":
    • "Comprise" is interchangeable with "include."
    • The whole comprises the parts.
    • The parts compose the whole.
    • "Comprised of" is never correct; "composed of" is correct
    • "Comprised in" is correct—parts are comprised in the whole.
  3. Use of "that" and "which":
    • "That" is restrictive; the clause is necessary for the meaning of the sentence and cannot be set off by a comma: The field that we are visiting was drilled in 1982.
    • "Which" is nonrestrictive; the clause is not necessary for meaning of the sentence and is set off by a comma: The field, which was drilled in 1982, was never as productive as expected.
  4. The word "data" is always plural and requires a plural verb; "datum" is singular.
  5. Use of "from" and "to": In measurements, if you use "from," you must use "to."
    • Correct: from 10 to 20 ft.
    • Incorrect: from 10–20 ft
  6. "Outcrop" is a noun; "crops out" is the verb form.
    • Correct: The Reagan Sandstone crops out in this county.
    • Incorrect: The Reagan outcrops in this county.
    • Correct: The Reagan outcrop can be seen over there.
  7. "Approximately" is used for measurement approximations; "about" is used for time approximations (preferred usage, not absolute; vary your usage to avoid repetition). Do not use such locutions as "approximately 4.31 cm"; the use of decimal places indicates that the number is not an approximation.
  8. Since, as, because:
    • "Since" refers to time; don't use it for "because."
    • Avoid using "as" whenever possible because it can be misused in too many ways; use "because" when appropriate.
  9. Use "due to" only after a form of the verb "to be":
    • The bad results were due to the poor sampling distribution.
    • If there is no form of the verb "to be" in the clause, then use one of the following forms in place of "due to": because of, as a result of, resulting from.
  10. Avoid making verbs out of adjectives or nouns:
    • "upslopes," "downdips"
    • Incorrect: The rock unit downdips at an acute angle.
  11. Location-designation style:
    • SE SE NW sec. 10, T. 15 S., R. 25 W., means the southeast quarter of the southeast quarter of the northwest quarter of section 10, township 15 south, range 25 west.
  12. Highway designation:
    • US-160 (U.S. highway 160)
    • K-10 (Kansas highway 10)
    • I-35 (interstate highway 35)
  13. Refer to each table, plate, or figure (in text, abbreviate to fig. or figs.) in the text in sequential order. That is, do not cite fig. 3 before fig. 2. By convention, we say "in" tables and figures and "on" plates, maps, and sheets.
  14. "Saltwater," "freshwater," and “groundwater” are each one word and are used this way whether as a noun or an adjective; "surface water" is a two-word noun and is used with hyphens when used as a unit modifier before nouns, i.e., "surface-water management."
  15. In technical writing, always use the active voice rather than the passive voice. Avoid the use of "There is…." ("Stratigraphers today highly esteem the geologic studies of that researcher" is preferable to "The geologic studies of that researcher are highly esteemed by stratigraphers today.")
  16. SI (International System of Units) measurement units (i.e., metric units) are preferable in manuscripts. If non-SI units are used (inch, foot, etc.), give the equivalent conversion. In measured sections, always give the units in the way in which they were measured first and the conversion second.
  17. The plural of foraminifer is foraminifers, not foraminifera. Foraminifera (capitalized) is the order and should not be used as the plural form.
  18. Eustasy, not eustacy.
  1. Capitalize formal names of geologic units:
    • Aarde Shale Member
    • Topeka Limestone
  2. Use lowercase letters for informal names of geologic units:
    • Excello shale member
    • Loveland formation
  3. If all the units in a group or list are formal, capitalize the plural:
    • the Foraker and Topeka Limestones
    • the Eudora and Rock Lake Shale Members
    • the Eudora Shale and Neva Limestone Members
    • Chase and Kansas City Groups
  4. If only some of the units in a list or group of units are formal or if all of them are informal, use lowercase letters for the plural:
    • The Topeka and Luta limestones
    • The Iatan and Idenbro limestone members
    • The Quivira and Peoria formations
  5. Use the following short forms for rock units:
    • Rock Lake Shale Member: Rock Lake Member, the Rock Lake, the member (not Rock Lake Shale; use Rock Lake shale only to mean shale within the Rock Lake Member)
    • Topeka Limestone: the Topeka
  6. Avoid using "Formation" when the unit is formally named with a rock type:
    • Topeka Limestone, not Topeka Formation.

Commonly used abbreviations (MC indicates usage on maps and charts only)





American Association of Petroleum Geologists




American Chemical Society


(note: small caps)


American Geological Institute


American Geophysical Union






American Petroleum Institute






American Society for Testing and Materials




bachelor of arts


(note: small caps)


bench mark (MC)


barrels of oil


barrels of oil per day


before present (note: small caps)


bachelor of science








common data point

Cgl., cgl.

conglomerate (MC)


Central Kansas uplift


Central North American rift system


Central stable region




darcy, darcies

Dol., dol.

dolomite (MC)


for example

et al.

and others


et cetera

fig., figs.

figure, figures

Fm., fm.

Formation, formation (MC)


Geodata interactive management map analysis and production

Gp., gp.

Group, group (MC)


Geological Society of America




that is




latitude (MC)


longitude (MC)

Ls., ls.

Limestone, limestone (MC)


master of arts



Mbr., mbr.

Member, member (MC)


Midcontinent Geophysical Anomaly




Mount (MC)


Mountain (MC)


Mountains (MC)


new species

no., nos.

number, numbers


Nemaha uplift

p., pp.

page; also pages





Qtz., qtz.

quartz (MC)


quadrangle (spell out in text)

R., Rgs.

range, ranges


railroad (MC)



Sh., sh.

Shale, shale (MC)


spontaneous potential

sp gr

specific gravity



Ss., ss.

Sandstone, sandstone (MC)

Sts., sts.

Siltstone, siltstone (MC)

T., Tps.

township, townships




U.S. Geological Survey (MC and tables; in text, spell out on first reference)







acre-feet or acre-foot


atomic mass unit




atomic unit

at. wt

atomic weight



billion ft3; BCF

billion cubic feet


British thermal units


billion years


degrees Centigrade; Celsius









cm, cm2, cm3

centimeter, square centimeter, cubic centimeter







cycle, c

cycle (use c only in combination: c/sec)





°, deg





electromagnetic unit


electrostatic unit


electron unit


electron volt


degrees Fahrenheit





ft, ft2, ft3

foot, square foot, cubic foot








gallons per minute
















Kelvin (note: no degree mark with Kelvin)


thousands of years ago (not to be confused with k.y.)



km, km2, km3

kilometer, square kilometer, cubic kilometer


thousand years (used for durations)




liter (when prefixed, e.g., ml)







m, m2, m3

meter, square meter, cubic meter


molal (concentration)


molar (concentration)


million years ago (not to be confused with m.y.)


thousand cubic feet




million gallons




reciprocal ohm (interchangeable with siemens)

mi, mi2, mi3

mile, square mile, cubic mile








million cubic feet





mol %

mole percent


miles per hour




meters per second




million years (used for durations)

m.y. b.p.

million years before present (better usage is Ma)




normal (concentration)
















picocuries per liter


parts per billion (preferred usage is X109)


parts per million (preferred usage is X106)


pounds per square inch






revolutions per minute


siemens (interchangeable with mho)









trillion ft3

trillion cubic feet





vol %

volume percent







wt. %

weight percent