Jason Rudolph, Fall 2002 through Spring 2003. Jason conducted a petrographic and structural investigation of the rhyolites exposed at Hughes Mountain in the St. Francois Mountains, southeastern Missouri, to determine the cause of the unusual columnar jointing in this rock unit.

Christopher Stitz, Spring 2001.  Chris used the ArcInfo GIS system to compile and plot the significant amount of structural attitude data Tom Moeglin and I had collected over the preceding decade in the Mummy Range of north-central Colorado.

Cheryl Mathenia, Fall 2000 through Spring 2001. Cheryl used x-ray diffraction to study the structural state of the K-feldspar in the granites exposed in the Taum Sauk Caldera of the Proterozoic Saint Francois Mountains Complex of southeastern Missouri.  Cheryl presented the results of her study at the annual meeting of the Missouri Academy of Science at Missouri Southern State College in Joplin on April 20, 2001.  Cheryl was awarded first prize in the Geology Section of the Collegiate Division for her presentation.   The results of this study were published as a full-length journal article in Transactions of the Missouri Academy of Science in 2003.

Meredith Kenworthy, Spring 1999 through Spring 2000. Meredith conducted a detailed petrographic study of the Early Proterozoic biotite schist exposed in the northern Mummy Range in north-central Colorado. Meredith prepared thin sections of a number of samples and identified the metamorphic minerals present in this rock unit.

Jason Smith, Summer 1998 through Spring 1999. In a research project funded by a grant from the Petrified Forest Museum Association, Jason collected and is currently analyzing samples from the three mafic volcanic structures exposed within Petrified Forest National Park. He will be studying these samples petrographically and geochemically to determine the genetic relationship between these rock bodies and the more extensive fields of volcanic structures in northern and eastern Arizona.  Results of this study were presented at the annual meeting of the Rocky Mountain Section of the Geological Society of America in Albuquerque, New Mexico, in April 2001.

Aaron Johnson, Fall 1996 through Spring 1997. As a continuation of Amy Woolsey's study (above), Aaron performed bulk geochemical analyses on samples of the mafic dikes exposed in the Silvermines area of the St. Francois Mountains of southeastern Missouri. His data was combined with that from Amy's study to quantify the geochemical effects of the quartz and feldspar xenocrysts on the crystallization of these late-stage mafic magmas. Aaron presented the results of his study at the annual meeting of the Missouri Academy of Science at Warrensburg on April 18, 1997. Aaron was awarded second prize in the combined Chemistry/Geology Section of the Collegiate Division for his presentation.

Jennifer Rusher, Fall 1996. Jennifer made thin sections of all the rocks studied by Kendall, Clark, and Shepard (above) and examined these thin sections petrographically to determine the extent of the hydrothermal alteration of the feldspars. Jennifer's data will be combined with the results from the three x-ray diffraction studies and will be submitted for publication as a full-length journal article in the near future.

Lisa M. Shepard, Fall 1995 through Spring 1996. Lisa used x-ray diffraction to study the structural state of the K-feldspar in the Stono Mountain Granite, a small pluton exposed near the northwestern corner of the Proterozoic Saint Francois Mountains Complex of southeastern Missouri. Lisa presented the results of her study, along with the results of the studies by Kendall and Clark described above, at the annual meeting of the Missouri Academy of Science at Drury College on April 19, 1996. Lisa was awarded first prize in the Geology Section of the Collegiate Division for her presentation.

Kenneth C. Clark, Fall 1994 through Spring 1995. K.C. used our new x-ray diffraction system to study the structural state of the K-feldspar in the rhyolitic tuffs exposed around the perimeter of the Butler Hill–Breadtray caldera in the Proterozoic Saint Francois Mountains Complex of southeastern Missouri.

James Kendall, Fall 1993 through Spring 1994. Jim used x-ray diffraction to study the structural state of the K-feldspar in the ring plutons surrounding the Butler Hill–Breadtray Granite, exposed near the center of the Proterozoic Saint Francois Mountains Complex of southeastern Missouri. Jim's study was the first to make use of our newly acquired $120,000 Scintag XDS-2000 x-ray diffraction system.

Sheryl Ervin, Fall 1993 through Spring 1994. Sheryl's second GLG 499 project under my direction was a study of the effect of Springfield's Southwest Sewage Treatment Plant on the quality of the water in Wilson's Creek and the James River. Each week for an entire year Sheryl sampled the water at five separate sites and analyzed these samples for pH and dissolved chlorides, phosphates, and nitrates. Sheryl presented the results of this study at the annual meeting of the Missouri Academy of Science in Cape Girardeau on April 29, 1994.

Amy Woolsey, Fall 1992 through Spring 1993. Amy studied the chemical alteration of K-feldspar xenocrysts in a basaltic dike exposed in the St. Francois Mountains of southeastern Missouri. She used the energy-dispersive x-ray microanalysis system on our new scanning electron microscope to map the migration of several elements between the xenocrysts and the basaltic matrix. Amy presented the results of her study at the annual meeting of the Missouri Academy of Science in Kansas City on April 23, 1993.

Sheryl Ervin, Fall 1992 through Spring 1993. Sheryl compiled and statistically analyzing the 10,000+ water quality analyses performed over the past ten years by the Greene County Health Department to determine if there were any patterns in this massive data set which would indicate significant changes in the quality of our drinking water.

William Eilers, Fall 1992 through Spring 1993. Bill conducted a detailed petrographic study of the Early Proterozoic granitic gneiss that Tom Moeglin and I have been mapping in the northern Mummy Range in north-central Colorado. Bill cut thin sections from approximately fifty samples of this rock unit and performed detailed modal analyses (point counts) on these thin sections to determine the range and spatial distribution of the mineralogical variation within this rock unit.

David Overhoff, Summer 1991. Dave served as a summer field assistant for Tom Moeglin and me in our mapping of the Proterozoic geology of the northern Mummy Range in north-central Colorado.

Richard Heyman, Fall, 1991. Richard adapted several geologic computer programs that I had written in FORTRAN on a mainframe so that they could run on our newly acquired Macintosh microcomputers.

Michael Morton, Fall 1990. Mike developed the procedure for fusing rock samples in molten lithium tetraborate to produce glass disks that can be analyzed chemically using the energy-dispersive x-ray microanalysis system on our new scanning electron microscope.

David Joslyn, Spring 1990. Dave collected samples of the rhyolitic ash-flow tuffs exposed in the St. Francois Mountains of southeastern Missouri and studied these rocks petrographically to determine the textural and mineralogical variation in each mapable unit.

Scott Helm, Spring 1988 through Summer 1989. Scott did the preliminary petrographic analysis of the plutonic and metamorphic rocks exposed in the remote central portion of the northern Mummy Range in north-central Colorado. The purpose of Scott's project was to characterize each of the rock units that Tom Moeglin and I were mapping in this high-grade Proterozoic terrane. During the three semesters of this project Scott cut numerous thin sections and petrographically analyzed each of these to estimate the range of abundance of each of the minerals present in each of our rock units. Scott also served as our summer field assistant on this project in both 1988 and 1989.

Chris Daniel, Fall 1987 through Spring 1989. Chris studied the structural state of the K-feldspar in the Butler Hill–Breadtray Granite, the largest pluton exposed in the Proterozoic Saint Francois Mountains Complex of southeastern Missouri. Chris used both petrographic and x-ray techniques to determine the range of variation of Al-Si ordering and the extent of hydrothermal/metasomatic alteration of the K-feldspar in this pluton. Results of this study were presented at the annual meeting of the north-central section of the Geological Society of America in Notre Dame, Indiana, in April, 1989, and were subsequently published as a full-length journal article (Plymate, Daniel, and Cavaleri, 1992).

Tom Pallesen, 1981. Tom used the universal stage on our research petrographic microscope to study the variation in the optic angle 2V for the alkali feldspars in a suite of granodiorite samples from the Rader Creek Pluton in southwestern Montana. These samples were the same ones I had studied in my M.S. research project at Indiana University. Tom found some of the same structural state variation I had found using x-ray techniques, but he concluded that this optical technique was significantly less efficient than the x-ray techniques I had developed. His conclusion was incorporated into the article I published on this study in Journal of Sedimentary Petrology in 1983.

Danja Feeback, 1980. Danja studied a suite of andesitic sills exposed in Cottonwood Canyon in southwestern Montana. She collected a set of samples from these sills, separated the potassium feldspar from the fine-grained matrix in each sample, and analyzed these K-feldspar concentrates by x-ray diffraction to determine the variation in structural state.