Geology Department

If you are interested in Earth—how it developed and what may happen to it in the future, how it functions as a complex physical and chemical system and why we should care, where life originated and how and why our planet supports us, and how our actions affect the world around us—a major in geology may be right for you.

The Department of Geology possesses extensive rock, mineral, and fossil collections as a basis from which to investigate Earth, a micro X-ray-fluorescence (micro-XRF) spectrometer for mapping rock and mineral elemental compositions, a powder X-ray diffractometer (powder-XRD) for determining mineral identities, research-grade stereo and petrographic microscopes, and rock and sediment-sample processing equipment. The department also houses the College’s scanning electron microscope (SEM) equipped with an energy-dispersive X-ray-fluorescence spectrometer (EDS) for micron-scale imaging and elemental analyses. Additional research equipment available for student use, shared with other departments in the Division of Natural Sciences, includes a C,H,N,O,S elemental analyzer, an inductively coupled plasma atomic emission spectrometer (ICP-AES) for determining elemental compositions, and the Colby Compass, a research vessel equipped with an array of instrumentation for real-time environmental analyses.

Colby’s setting provides an intriguing and exciting area for field study, enabling students to integrate field and laboratory experiences. Students are encouraged to engage in independent and honors research projects with faculty. Research opportunities are offered routinely during the summer by departmental faculty at Colby and abroad.

Fieldwork is an integral part of geology courses and introduces students to various aspects of local and regional geology. Multi-day off-campus trips are scheduled regularly to localities and areas of particular geologic interest, such as the Hartford Basin of Connecticut, the Mohawk Valley or Catskill Mountains of New York, the classic Joggins and Brule localities in Nova Scotia, and late Paleozoic rocks of New Brunswick. The department also provides off-campus international experiences, including study in Bermuda.

The Geology Department offers both a major and a minor for students with different interests. The point scale for retention of the major applies to all courses taken in the major; no requirement may be taken satisfactory/unsatisfactory. Students should consult regularly with their advisor in selecting courses appropriate for meeting their goals for post-graduation employment and/or graduate study.


ChairAssociate Professor Walter “Bill” Sullivan
Associate Professors Tasha Dunn and Walter “Bill” Sullivan; Assistant Professors Bess Koffman and Alejandra Ortiz; Visiting Assistant Professor Bruce Rueger

Requirements +

Requirements for the Major in Geology

Requirements for the geology major are:

  • A 100-level gateway course (Geology 122, 123, 125, 127, 129, or 141)
  • Four core courses (Geology 228, 231, 254, and 262)
  • Four geology elective courses numbered 200 or above
  • Three credits of geology seminar (Geology 391)
  • Geology 494 or six credits of honors-thesis research (Geology 483/484); and
  • Two cognate courses from the following list: Biology 163, 164; Chemistry 121, 122, 141, 142, 147; Computer Science 151, 152, 153; Physics 141, 143, 145; Math 120j, 125, 130, 135, 160, 165; and Statistics 212.

Geology majors may substitute one course in biology, chemistry, computer science, GIS, mathematics, physics, or statistics numbered 200 or above (excluding Statistics 212) for one of the four geology elective courses. A single independent research project earning at least four credit hours of Geology 491/492 during the student’s senior year also may count as a major elective. Additional course work in chemistry, physics, and mathematics beyond the minimum requirements is strongly encouraged to broaden students’ skill sets and maximize options after graduation. Students should consult one of the major advisors in the first and second years regarding election of languages and other Colby-required courses.

Requirements for Honors in Geology

The Geology Department’s honors program involves a substantial research component in the student’s senior year, with no fewer than six credit hours of Geology 483/484 and completion of a thesis detailing this work. Participation in the honors program requires a 3.5 GPA in the major by the end of the junior year before a faculty sponsor can consider the project. The honors program involves presentation of a research proposal to a faculty committee early in the fall semester, drafting and approval of introductory sections before January, submission of a full draft of the thesis for review by spring break, and approval of the final thesis by the faculty committee. Satisfactory progress will result in credit for Geology 483 and 484. Successful completion of an honors research project, and the major, will enable the student to graduate with “Honors in Geology.” Students who wish to pursue an even more intensive research agenda should consider the Senior Scholars Program, an all-campus honors program in which half the student’s academic credits in the senior year are devoted exclusively to a major research project.

Requirements for the Minor in Geology

A minor in geology is available to students majoring in other disciplines who also desire an introductory understanding of the Earth sciences. Minor programs are tailored to the needs of individual students; courses should be elected in consultation with the minor advisor. Requirements are:

  • A 100-level gateway course (Geology 122, 123, 125, 127, 129, or 141)
  • Four geology courses selected from courses numbered 228 and above.