The tutorial has content that is potentially of interest to a wide range of students, from introductory-level through graduate. The tutorial is also used in industry labs.

Ideally, students should have previous exposure to some of the main concepts in mineralogy and crystallography. Optical mineralogy is not necessary, but preferred.

Used as a supplement to laboratory exercises.

Goal is to enhance skills with petrographic identification of detrital and authigenic features in sandstones. For each of the major sandstone clans there are separate tutorials on both provenance and diagenesis.

The focus is on learning to interpret data from visual observations of components that display large heterogeneity. The student must learn to systematize rather subjective information into "either or" hypotheses from which a specific determination can then be chosen.

An understanding of the microscale structure and composition of sedimentary rocks is of undiminished importance in diverse fields (e.g., microscale chemical analysis cannot proceed without petrography), yet the curriculum is no longer offering undergraduates the opportunity to develop sufficient expertise. In an effort to bolster the exposure of undergraduates to sedimentary petrology, the Tutorial Petrographic Image Atlas was created. The basic components of the tutorial are petrographic images that are viewed in a static mode (no rotation, no animation, no timed observation). Text boxes relating to identification of components within the image are attached to specific mapped regions of the image. Both the mapped regions and the text are invisible until the student points and clicks on an active region of the image. In essence, the student must 'ask', "What is that?" Information ranges from simple one word identifications to lengthy paragraphs explaining the finer points of why something is what it is.

This is a highly interactive digital product that attempts to recreate certain elements of the laboratory petrographic experience including: a sense of exploration; high-quality petrographic images; a visual field dominated by the image; multiple examples of features viewed in diverse contexts; rich content relating to the identification and significance of features; active, inquiry-based learning.

Unlike real-time laboratory experiences with the petrographic microscope, the digital tutorial can be used at any time and place that a computer is available, does not require the presence of a microscope or samples or an expert, can be viewed repeatedly, has the technical content integrated with the image, gives the student undivided "attention" (unlike the TA, it doesn't wander to the other side of the lab), and rarely gives answers unless "asked."

Evaluation is determined by student performance on laboratory tests of identification skills.

Peer-reviewed materials
Choh, S.-J. and Milliken, K. L., 2004, Virtual carbonate thin section using PDF: new method for interactive visualization and archiving: Carbonates and Evaporites, v. 19, p. 87-92.

Choh, S.-J., Milliken, K. L. and McBride, E. F., 2003, Architecture and development of an interactive program for teaching highly visual material: a tutorial for sandstone petrology: Computers and Geosciences, v. 29, p. 1127-1135.

Milliken, K. L., Barufaldi, J. P., McBride, E. F. and Choh, S.-J., 2003, Assessment of an interactive digital tutorial for undergraduate-level sandstone petrology: Journal of Geoscience Education, v. 51, p. 381-386.

Milliken, K. L., Choh, S.-J. and McBride, E. F., 2002, Sandstone Petrology, v. 1.0, A Tutorial Petrographic Image Atlas, Multimedia CD-ROM: American Association of Petroleum Geolo-gists/DataPages, Discovery Series No. 6, Tulsa, Oklahoma.

Non-peer-reviewed
Choh, S-J., Milliken, K. L. and McBride, E. F., 2002, Interactive sandstone petrology: a digital tutorial for future reservoir geologists: Search and Discovery, invited submittal, http://www.searchanddiscovery.com/documents/choh/index.htm

Abstracts
Milliken, K. L. and Choh, S.-J., 2006, Using petrographic data from electron microbeam instrumentation in the curriculum: Digital resources can help: Geological Society of America Annual Meeting, Abstracts with Programs, v. 38, invited submission, Session T53, "Teaching Instrumentation to Geoscience Students: Course Design, Objectives, and Presentations"

Milliken, K. L. and Choh, S.-J., 2005, An interactive digital carbonate petrology tutorial for next generation geoscientists: Geological Society of America Annual Meeting, Abstracts with Programs, v. 37, no. 7, p. 254.
Choh, S-J. and Milliken, K. L., 2004, Constructing an interactive sandstone petrology CD for undergraduates: bringing a classical subject into the digital age: Geological Society of America Annual Meeting, Abstracts with Programs, v. 36, no. 5, p. 236.

Choh, S-J., Milliken, K. L. and McBride, E. F., 2001, Interactive sandstone petrology: A digital tutorial for future reservoir geologists: American Association of Petroleum Geologists Annual Meeting (Abstracts), p. A35.

Choh, S-J. Milliken, K. L. and McBride, E. F., 2001, Multimedia "sandstone petrology tutorial" for under-graduate sedimentary rocks laboratory: will enhanced learning lead to improved enrollment?: Geological Society of America Annual Meeting, Abstracts with Programs, v. 33, no. 6.