BUD WOBUS, UNDERGRADUATE RESEARCH AND THE PIKES PEAK BATHOLITH

Bud Wobus’ career spanned a time when undergraduate research evolved from being a relatively rare student experience to a significant component of a geosciences education. He was a pioneer in championing the undergraduate research enterprise beyond Williams College. The Keck Geology Consortium (KGC) was established in 1987, largely due to Bud’s vision for collaborative, field-based research across predominantly undergraduate institutions. In 1988, Bud was one of 11 faculty that founded the Geology Division of the Council of Undergraduate Research (cur.org), a national organization that supports and promotes undergraduate research.

Prof. Wobus worked with the USGS in the 1970s-80s, mapping and characterizing the 1.08 Ga Pikes Peak Batholith (PPB). Numerous small, late-stage plutons emplaced in the PPB were subdivided into (1) a sodic series (SiO₂ ~44-78 wt %) and (2) a potassic series (SiO₂ ~70-77 wt %). These plutons were the focus of a KGC project in 1992-93, which engaged three faculty co-directors, ten undergraduate students, and eight faculty as field visitors/workshop participants. Student participants utilized mineralogy, major and trace element geochemistry, and Sm-Nd isotopes to place constraints on the petrogenesis of the late-stage plutons. Results were documented in three journal articles and numerous conference abstracts and senior theses. We concluded that the potassic granites are crustal melts derived from tonalitic sources with minor fractionation dominated by feldspar, whereas the syenites and granites of the sodic series are fractionation products of mantle-derived mafic magmas with minor crustal input.

There seems to be keen interest in the PPB, based on the number of citations (>200) and downloads (>4000) of articles that resulted from the KGC project. A review of the literature reveals that new work is limited to PPB pegmatites and two of the late-stage intrusions, thus there are opportunities for future studies that would lend further insights to the petrogenesis of PPB magmas.

The PPB project was one of nine KGC projects that Bud (co-)directed, engaging a total of 75 students. At Williams, he mentored 48 research students, almost half of whom were women. Bud Wobus’ impact on undergraduate education and research at Williams College, as well as across the nation, cannot be overstated.