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In 2002 President Martin Jischke initiated a new era in strategic planning at Purdue. Under his leadership, strategic planning became a centralized activity with unit plans aligned to the university plan. Strategic goals were designed to have maximum impact, which would be measurable through metrics. Strategic planning at Purdue would be an outward-facing activity--a public expression of the university's progress and its value to the state and its broader constituent base. The senior leadership team of Purdue Extended Campus (PEC) developed its first strategic plan in this new environment for 2003-2008. Building on its success with the first plan, PEC had the confidence to make significant adjustments both in terms of focus and process. Where the first plan focused on the unit and, in turn, the university, the second, "Engaging Customers--Delivering Solutions," sought to have an impact on the people that PEC served. And where the first plan was top-down, the second involved stakeholders more deeply at every phase of development. This case study describes PEC's experience with the 2009-2014 plan, from the process of planning to implementation and assessment, and concludes with lessons learned.

Accurate assessment of the duration of zircon crystallization within igneous rocks is critical for constraining the time scales of magmatic evolution and storage, which have important implications for our understanding of magmatic fluxes and volcanic hazards. However, estimation of crystallization durations from finite geochronologic data sets is difficult and typically relies on numerous implicit assumptions. In this contribution, we evaluate these assumptions and provide recommendations for better interpretation of crystallization durations from individual samples by developing a simplified theoretical framework to relate zircon growth, nucleation, and armoring rates to zircon ages. We first investigate single zircon analyses and show that ages produced with methods that integrate the entire grain or grain fragments (e.g., chemical abrasion-- isotope dilution--thermal ionization mass spectrometry [CA-ID-TIMS]) are inevitably biased toward the second half of the zircon growth interval, while subsampling of grains via microbeam approaches will only capture the majority of the zircon crystallization duration when the microbeam spot size is less than ~25% of the zircon minor axis, and the analytical uncertainty of the measurement is less than ~20% of the duration over which the individual zircon grew. We subsequently investigate the distribution of zircon mean ages produced through various combinations of zircon growth rate, nucleation rate, and the probability of zircon being armored by major phases. We show that zircon age distributions cannot be directly predicted from the rate of zircon mass crystallized, as many combinations of growth, nucleation, and armoring rates result in distinct age distributions, yet they produce nearly identical mass crystallization rates. Finally, we develop two equations that can be used to constrain the duration of crystallization observed within individual samples. In scenarios where the observed age dispersion is consistent with the reported analytical uncertainties, the first equation can be used to estimate the maximum duration. Otherwise, when the measured zircon population is overdispersed, a second equation constrains the minimum duration of zircon crystallization. [ABSTRACT FROM AUTHOR]

Detrital zircon geochronology by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is a widely-used tool for determining maximum depositional ages, sediment provenance, and reconstructing sediment routing pathways. Although the accuracy and precision of U-Pb geochronology measurements has improved over the past two decades, Pb-loss continues to impact the ability to resolve zircon age populations by biasing affected zircon toward younger apparent ages. Chemical abrasion (CA) has been shown to reduce or eliminate the effects of Pb-loss in zircon U-Pb geochronology, but has yet to be widely applied to large-n detrital zircon analyses. Here, we assess the efficacy of the chemical abrasion treatment on zircon prior to analysis by LA-ICP-MS and discuss the advantages and limitations of this technique in relation to detrital zircon geochronology. We show that i) CA does not systematically bias LA-ICP-MS U-Pb dates for thirteen reference materials that span a wide variety of crystallization dates and U concentrations; ii) CA-LA-ICP-MS U-Pb zircon geochronology can reduce, or eliminate, Pb-loss in samples that have experienced significant radiation damage; and iii) bulk CA prior to detrital zircon U-Pb geochronology by LA-ICP-MS improves the resolution of Neoproterozoic to present zircon age populations and the percentage of concordant analyses in Mesoproterozoic and older age populations. The selective dissolution of zircon that has experienced high degrees of radiation damage suggests that some detrital zircon age populations could be destroyed or have their abundance significantly modified during this process. However, we did not identify this potential effect in either of the detrital zircon samples that were analyzed as part of this study. We conclude that pre-treatment of detrital zircon by bulk CA may be useful for applications that require increased resolution of detrital zircon populations. [ABSTRACT FROM AUTHOR]

The Cambrian diversification of animals was long thought to have begun with an explosive phase at the start of the Tommotian Age. Recent stratigraphic discoveries, however, suggest that many taxa appeared in the older Nemakit-Daldynian Age, and that the diversification was more gradual. We map lowest Cambrian (Nemakit-Daldynian through Tommotian) records of [[delta].sup.13] [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII.] variability from Siberia, Mongolia, and China onto a Moroccan U/Pb--[[delta].sup.13][MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII.] age model constrained by five U/Pb ages from interbedded volcanic ashes. The [[delta].sup.13] [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII.] correlations ignore fossil tie points, so we assume synchroneity in [[delta].sup.13]C trends rather than synchroneity in first appearances of animal taxa. We present new [[delta].sup.13][C.sub.org], [sup.87]Sr/sup.86]Sr, uranium, and vanadium data from the same carbonate samples that define the Moroccan [[delta].sup.13] [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII.] curve. The result is a new absolute time line for first appearances of skeletal animals and for changes in the carbon, strontium, and redox chemistry of the ocean during the Nemakit-Daldynian and Tommotian ages at the beginning of the Cambrian. The time fine suggests that the diversification of skeletal animals began early in the Nemakit-Daldynian, with much of the diversity appearing by the middle of the age. Fossil first appearances occurred in three pulses, with a small pulse in the earliest Nemakit-Daldynian (ca. 540-538 Ma), a larger pulse in the mid- to late Nemakit-Daldynian (ca. 534-530 Ma), and a moderate pulse in the Tommotian (ca. 524-522 Ma). These pulses are associated with rapid reorganizations of the carbon cycle, and are superimposed on long-term increases in sea level and the hydrothermal flux of Sr. doi: 10.1130/B30346.1

Plutons offer an opportunity to study the extended history of magmas at depth. Fully exploiting this record requires the ability to track changes in magmatic plumbing systems as magma intrudes, crystallizes, and/or mixes through time. This task has been difficult in granitoid plutons because of low sampling density, poorly preserved or cryptic intrusive relationships, and the difficulty of identifying plutonic volumes that record the contemporaneous presence of melt. In particular, the difficulty in delineating fossil magma reservoirs has limited our ability to directly test whether or not high-SiO2 rhyolite is the result of crystal-melt segregation. We present new high-precision U-Pb zircon geochronologic and geochemical data that characterize the Miocene Searchlight pluton in southern Nevada, USA. The data indicate that the pluton was built incrementally over ~1.5 m.y. with some volumes of magma completely crystallizing before subsequent volumes arrived. The largest increment is an ~2.7-km-thick granitic sill that records contemporaneous zircon crystallization, which we interpret to represent a fossil silicic magma reservoir within the greater Searchlight pluton. Whole-rock geochemical data demonstrate that this unit is stratified relative to paleo-vertical, consistent with gravitationally driven separation of high-SiO2 melt from early-formed crystals at moderate crystallinity. Zircon trace-element compositions suggest that our geochronologic data from this unit record most of the relevant crystallization interval for differentiation and that this process occurred in <150 k.y. [ABSTRACT FROM AUTHOR]