Geosciences (GS)

Geosciences emphasizes the application of general principles of geology, geochemistry, and geophysics to problems in the marine and terrestrial environments of the Earth. Graduate students routinely participate in expeditions at sea and on land and many doctoral theses evolve from these experiences.

Research areas in geological sciences include

  • The origin and evolution of the ocean-atmosphere system, global climate, and biosphere
  • Geology, geochemistry, and geophysics of oceanic crustal rocks and near-shore environments
  • Tectonic and structural evolution of the oceans, plate margins, and back-arc basins
  • The role of fluids in the crust
  • Chemistry of rare gases in active volcanoes
  • The use of natural nuclear processes for understanding physical and chemical processes in the Earth
  • Paleomagnetic applications in geology and geophysics

Requirements for Admission

In addition to the general requirements for admission to the PhD program listed here, a major in one of the earth sciences including undergraduate coursework in physical chemistry and calculus are required.  Preparation beyond the minimum requirements in mathematics, physics, and chemistry is strongly recommended.

Program of Study


Students admitted to Geosciences of the Earth, Oceans, and Planets (GEO) are assigned an adviser, who is the chair of their three-person guidance committee. Based on the student’s interests and the major affiliation of the adviser, students are assigned to a curricular group upon admission. Although students may change curricular groups in the course of the year, they must choose which departmental exam they will take. Departmental exams have similar structures among the curricular groups within GEO (a written exam at the end of spring quarter of their first year and an oral exam before the beginning of fall quarter of their second year). The material covered is quite different so students must begin preparing for a particular group's exam from the start. Student support for the first year comes from a variety of sources including departmental fellowships and research grants. Students are encouraged to begin a research project from the beginning and typically do not hold teaching assistant positions during their first year. Students may change advisers during their first year, and they must find an adviser by the end of the first year.

The geosciences curriculum consists of a series of core courses and a series of research focus courses.  Students are expected to take at least nine classes and at least four units of research per quarter during their first year for a total of at least forty-eight units.

All students are responsible for material in Marine Geology (SIO 240). Additionally students must take at least one geophysics, one geochemistry, and one geology class from the following groups of core classes:

Geophysics core classes include Introduction to Geophysics (SIO 103), Geodynamics (SIO 234), Rock Magnetism and Paleomagnetism (SIO 247), and Introduction to Marine Geophysics (SIO 226).

Geochemistry core classes include Marine Sediments-Paleo Proxies (SIO 245),  Whole Earth Geochemistry (SIO 251), and Introduction to Isotope Geochemistry (SIO 252A).

Geology core classes include Stratigraphy and Sedimentology (SIO 105), Introduction to Volcanology (SIO 170), Geological Record of Climate Change (SIO 201), Shape and Structure of the Ocean Floor (SIO 244), and Interactions of Oceanic Plates and the California Margin (SIO 253). 

Students are also encouraged to take Introduction to Computers at SIO (SIO 233), Analysis for Physical Oceanographic Data (SIO 221B), Physical Oceanography (SIO 210), Marine Chemistry (SIO 260), and Biological Oceanography (SIO 280), but these may not be used to substitute for the geology, geophysics and geochemistry core requirements.


The geosciences curriculum consists of a series of core courses and a series of research focus courses.

Required course work:

  • SIO 240. Marine Geology (4 units)
  • One geophysics course, from the following:
    SIO 103. Introduction to Geophysics (4 units)
    SIO 226. Introduction to Marine Geophysics (4 units)
    SIO 234. Geodynamics (4 units)
    SIO 247. Rock Magnetism and Paleomagnetism (4 units)
  • One geochemistry course, from the following:
    SIO 245. Marine Sediments-Paleo Proxies (4 units)
    SIO 251. Whole Earth Geochemistry (4 units)
    SIO 252A. Introduction to Isotope Geochemistry (4 units)
  • One geology course, from the following:
    SIO 105. Stratigraphy and Sedimentology (4 units)
    SIO 160. Introduction to Tectonics (4 units)
    SIO 170. Introduction to Volcanology (4 units)
    SIO 201. Geological Record of Climate Change (4 units)
    SIO 244. Shape and Structure of the Ocean Floor (4 units)
    SIO 253. Interactions of Oceanic Plates and the California Margin (4 units)

Elective course work:

Students may fulfill the remaining units of required course work through elective course offerings selected in consultation with the students’ guidance committee. Recommended course electives are below:

  • SIO 233. Introduction to Computers at SIO (4 units)
  • SIO 221B. Analysis for Physical Oceanographic Data (4 units)
  • SIO 210. Physical Oceanography (4 units)
  • SIO 260. Marine Chemistry (4 units)
  • SIO 280. Biological Oceanography (4 units)

Research in Geosciences

Of the sixteen categories of research at Scripps, the GS group is most closely associated with the following integrated research themes:

Geosciences Faculty and Researchers: