Desirable Preparation
General Examination
Dissertation
Equipment and Facilities

The Department of Geosciences covers a wide range of fields, and actively promotes interdisciplinary study and research.

Students with interest in structural geology, tectonics and geophysics, geochemistry, petrology, mineral physics,geochemistry, biological oceanography, paleontology, paleoceanography and paleoclimate and environmental geology will find most of their research and educational needs accommodated within the laboratories of Guyot Hall, where the Department is located. 

In addition the Department has associated programs in water resources (shared with Civil Engineering), materials science (in collaboration with the Princeton Materials Institute) and  environmental science (Geosciences is currently the leading department within the Princeton Environmental Institute). 

Atmospheric and ocean sciences are an integral part of the Department, but most of the AOS research activities take place at the Geophysical Fluid Dynamics Laboratory, which is located off campus (but is expected to move to campus by the year 2002). Most courses are already taught in Guyot Hall. 

We also provide an recently established computational geosciences as interdisciplinary graduate training program in Computer and Application Sciences-PICASso.
 

Desirable Preparation 
Advances in the earth sciences depend largely on a basic knowledge of mathematics, chemistry, physics, and biology and on the ability to apply these to geological problems. The best preparation for graduate work in this department combines a solid background in related sciences and mathematics with a basic introduction to the geological sciences. The department welcomes as candidates not only those students whose principal background is in geology, geophysics, or geochemistry, but also those who have concentrated in other sciences, such as biology, chemistry, mathematics, physics, or engineering. Only the Ph.D. program is offered, for which both beginning and advanced students may apply. 

General Examination 
The general examination for advancement to Ph.D. candidacy is normally taken before the end of the second year of graduate work. The examination is designed to establish the student's depth and breadth of knowledge in the chosen fields of specialization, acquaintance with scholarly methods of research, and the ability to organize and present research material. The examination is based in part on a written report submitted by the student describing the research activities undertaken during the first two years. A research progress report is also required at the end of the student's first year. 

The AOS program has a distinct physics/appied math flavour and a more formal course load. Its Genearl Exam has both a written and an oral component.

Dissertation 
The dissertation shall show that the candidate has technical mastery in the chosen field and is capable of independent research. It is expected to be a positive contribution to knowledge, which may consist of a new scientific generalization, a new body of integrated facts that carries scientific implications that extend beyond itself, or a substantial improvement in technique or procedure. The final public oral examination is a final examination in the field of study. In addition to defending the dissertation, candidates are expected to respond to questions relating to the specific principles involved in their research and to questions ranging widely over related subjects. The student's advisory committee will contain members of the faculty, including as appropriate, faculty from other departments. 

Equipment and Facilities 
Modern earth science has a continuum of approaches, ranging from field studies to laboratory and theoretical work using sophisticated instrumentation and large computers. In addition to collections of appropriate materials and the petrographic, mineralogic, sedimentologic, and paleontologic facilities to study them, the department has specialized equipment for laboratory and field studies of seismology and for experimental studies on rocks at high pressure and temperature; for crystal structural studies by X-ray diffraction and by ultraviolet, visible, infrared, and Raman spectroscopy; for the study of fluid inclusions, for argon 40/39 dating by conventional and laser techniques; for compositional and radioisotopic studies of ocean and river water; and for stable carbon, oxygen, and nitrogen isotope analysis of fluids, organic remains, and minerals. Extensive laboratory facilities for chemical and biological work include a wide array of analytical instruments, molecular biological and microbiological facilities, clean room, and state-of-the-art mass spectrometry. 

Geochemistry: Specific instruments include argon plasma and atomic absorption spectrometers; gas chromatographs, HPLC, and ion analyzers; infrared, ultraviolet and fluorescent spectrometers; gamma and scintillation counters; ultracentrifuges; a new Cameca electron microprobe, single-crystal cameras, and an automated powder X-ray diffraction system for work at room and high temperatures; field gun emission scanning  and transmission electron microscopes; dissolved- and solid-carbon analyzers; and modern wet-chemical laboratory facilities. There is also a hydrothermal laboratory, including large-capacity rocking autoclaves, kinetic flow systems, optical high-pressure and high-temperature cells, and an internally heated high-pressure system. 

The Ocean Tracer Laboratory includes alpha detectors and scintillation detectors for measuring low levels of radon and radium radioisotopes and a high-resolution intrinsic germanium well detector for gamma ray measurement. 

The Argon 40/39 Laboratory contains three fully equipped gas mass spectrometers, one devoted to a conventional step-heating extraction system, and the other two to laser microprobe extraction lines. The Stable Isotope Laboratory contains a new V. G. Optima gas source mass spectrometer, with peripheral devices for automated analysis of carbonate minerals and for automated loading and cleaning of CO2, H2O, and N2 gas mixtures. Off-line preparation facilities are available for water samples, organic materials, and minerals. 

Biological Oceanography Research focuses on carbon and nitrogen cycle processes and trace metals in the oceans.  Instruments include controlled temperature rooms for phytoplankton and bacterial culture, epifluorescence microscopes, centrifuges, scintillation counter, gamma counter, autoclave, atomic absorption spectrometer, laminar flow hoods, trace metal clean room, Europa 20/20 mass spectrometer, automated DNA sequencer, gel documentation system, and fully equipped molecular biological laboratories for protein and nucleic acid research. 

Geophysics and Structural Geology: The High-Pressure Mineral Physics Laboratory contains diamond anvil cells for high-pressure/temperature studies. Included in the facility are stereomicroscopes, microdrill, gas loading system, and photoluminescence, Raman and Brillouin spectroscopy. Access to second- and third-generation synchrotron radiation facilities is available. All these facilities are supported by a departmental machine shop and lapidarian shops. 

The Department owns three 6-channel digital portable seismometers along with support equipment for a wide variety of small-scale field experiments. In addition, we have developed low-cost broad band seismometers that are used in high schools around the country. For larger experiments abroad, we use portable seismographs from the Passcal Instrument Center. 

Much of the seismological data analysis and geodynamical computations are performed in our "computer laboratory," which consists of three computer workrooms with a dozen workstations,  a Beowulf cluster with 136 Pentium processors in parallel, a Sun Enterprise 3000 computer server, and numerous peripherals for text and color graphics output. And an expresso machine! We obtain our data from digital archives around the world, as well as from our own field experiments with portable seismic instrumentation (such as in the Sierras and on Iceland). Large disk storage devices ease the processing of seismological data considerably. 

We also have a "structural geology laboratory" consisting of a seminar/layout room and two computer workrooms with workstations (SGI and Sun), Macs, and peripherals for dealing with large maps and images. 

First-year graduate students in geophysics receive brief training to serve as assistant system managers for the computer labs. 

Paleontology: Under construction 

Library 
The department library collection holds more than 75,500 volumes (with an additional 25,000 volumes in a storage facility) including all major domestic and foreign journals in the earth sciences and worldwide government survey publications. The library's map collection contains over 300,000 geologic, topographic, physical, cultural, and political maps. The library also houses the Digital Map and Cartographic Information Center which provides access to geospatial data, digital map services, GIS, reference, instruction and consultation. The library has remote and local electronic access to all major indexes covering the sciences and technology.