About pkz

I'm a professor of earth and environmental sciences at Lehigh University. My path to get here meandered a bit. After originally considering an English major at Dartmouth and after a first year that included much climbing and a gentleman's C in chemistry, I recovered to take an undergraduate degree in 1978 in Earth Sciences before earning my Ph.D. in geology in 1983, also from Dartmouth. I then spent five years as a research fellow in isotope geochemistry with Ian McDougall at the Research School of Earth Sciences of the Australian National University in Canberra.

Research: My research interests have continued to follow two main threads. I've always been interested in development of techniques in geochronology, with a focus on noble-gas methods and thermochronology and their application to tectonics. I'm also interested in crustal geodynamics, the nature and origin of mountains, and the geologic evolution of Asia, where I've worked for 45 years (!!) in the Himalaya, Tibet, and Mongolia.

Professional activities: For many years I served as a panel member for the Continental Dynamics program of the U.S. National Science Foundation. Currently, I serve on the editorial boards of the new AGU open-access journal AGU Advances and the AGU preprint archive essopenarchive.org, and I am on the editorial advisory board of Earth and Planetary Science Letters. I'm also Chair of the International Standing Committee on Thermochronology, which organizes the thermochron community and oversees the continuity and planning for international conferences every two years. I'm honored to have been named a Fellow of the American Geophysical Union in 2013 and to have received the Dodson prize in thermochronology in 2016 and Lehigh's Libsch research award in 2019.

At Lehigh: I've served as EES department chair from 1997-2002 and 2004 to 2007. I teach graduate courses about tectonic processes and geochronology, and undergraduate courses about the Earth system and energy issues. I've also taught first-year seminars on such topics as energy, disaster movies, Himalayan exploration, and environmental change. I helped plan and implement Lehigh’s South Mountain College, a residential intellectual community and academic program for undergraduates that focused on examination of important issues and ideas across disciplines, and I served as the SMC program’s inaugural director from 2007 to 2009. Currently I am Vice-Chair of the Lehigh Faculty Senate, and will serve as senate chair from 2024 to 2026.

Current Research Interests

I'm currently working in three main areas: regional-scale tectonics and geodynamics in Mongolia, integration of multiple thermochronometers to assess exhumation in the Neoproterozoic, and examination of what controls helium diffusion kinetics and age dispersion in apatite. In general I remain interested in the influence that surface processes have on tectonic processes and dynamics, and what sort of Earth-system feedbacks might involve the solid Earth. By training I'm a geochronologist, and the lab we maintain here at Lehigh carries out a range of applications in noble-gas geochronology (U-Th/He and Ar-Ar). Though we have particular expertise in lower-temperature thermochronology, our work generally involves integrating such data with results from multiple dating methods and constraints obtained from other disciplines. In 2012 we took delivery of an Argus VI multicollector noble-gas mass spectrometer which has proven to be a great instrument. Most recently we're using diode-laser heating to investigate U-Th/He analysis using cumulative heating. But through it all, the lab has remained... proudly acronym-free!

Students

Current Students

• Drew Spatz (Ph.D. candidate, current) Application of detrital-zircon and thermochronogical data to the tectonic evolution of the U.S. east coast.

Recent Students

• Hongcheng Guo (Ph.D. candidate, 2022) Assessment of crystal imperfections as a cause of dispersed U-Th/He ages; timing of rock uplift of the Altai Ranges in Mongolia; use of detrital white mica ages to examine climate controls on erosion.
• Jennifer Schmidt (Ph.D. 2018) "Revealing a Cenozoic history of landscape change and differential unroofing in the southeastern Lhasa Block: Applications of thermochronometry along the Tibetan Plateau margin".
• Lenny Ancuta (Ph.D. 2017) "Toward an improved understanding of intraplate uplift and volcanism: Geochronology and geochemistry of intraplate volcanic rocks and lower-crustal xenoliths" (Mongolia).
• Darwin Janes (M.S. 2017, "Characterizing defects and dislocations in apatite using scanning electron microscopy: Implications for U-Th-Sm/He dating".
• Kalin McDannell (Ph.D. 2017) "Methods and application of deep-time thermochronology: Insights from slowly-cooled terranes of Mongolia and the North American craton".
• Janelle Thumma (M.S. 2016) "Assessing the timing of intracontinental uplift of the Gobi Altai, Mongolia using low-temperature thermochronology".

Research Facilities

Facilities for research in geochronology include systems for U-Th/He and ⁴⁰Ar/³⁹Ar geochronology (with both furnace, and UV and CO₂ lasers). Relevant supporting facilities include a stable-isotope geochemistry laboratory housed within the department, and excellent facilities for sample characterization housed in other departments on campus.

Current Projects

Geodynamics of the Altai Ranges in Mongolia

In collaboration with Anne Meltzer and Frank Pazzaglia at Lehigh, we have carried out reconnaissance work on how the Altai ranges in western and southwestern Mongolia might be used a laboratories for studying the tectonics and geodynamics of intracontinental deformation. Growth of these ranges may have been important in contributing to long-term climate evolution in the northern hemisphere during the Cenozoic, but the timing and the causes of deformation and uplift remain poorly known. So far we've made two trips to the Altai, in 2017 and 2018, with the 2018 trip including Lehigh graduate students Hongcheng Guo, Adrienne Scott, and Katrina Gelwick. Janelle Thumma contributed to our work through her M.S. thesis on the timing of uplift of the Gobi Altai fault blocks, south of the Hangay. We're currently working on a proposal for a large interdisciplinary project that would incorportate work on the Altai.

Timing and Magnitude of Cratonic Exhumation in the Neoproterozoic

In collaboration with Willy Guenthner at the University of Illinois at Urbana-Champaign, Brenhin Keller at Dartmouth, and Kalin McDannell at the Geological Survey of Canada-Calgary, we are using a multichronometer approach to examine the extent, magnitude, and timing of what appears to have been a widespread period of cratonic exhumation in the Neoproterozic. A fundamental question is whether this exhumation, which reaches some 8 km in places, reflects erosion by Snowball-Earth glaciation, was a trigger for this glaciation through CO2 drawdown, or both, in the sense that feedbacks developed between solid-Earth exhumation and glacial erosion. We're currently seeking funding to support an initial phase of this work, which will examine existing samples from several cratonic blocks that made up part of the Rodinia supercontinent.

Collaborative Research: Impact of Crystal Defects on He Diffusion in Apatite (NSF)

This project is examining the role that crystal imperfections of various types have on the diffusion of helium in apatite. THe work is a collaboration with Bruce Idleman at Lehigh and Annia Fayon at University of Minnesota-Twin Cities. Ph.D. student Hongcheng Guo is also working on the project as part of his dissertation. The project involves both developing the Continuous Ramped Heating method as a screening and assessment tool (Lehigh group), and more fundamental research on the nature of defects in apatite and their impact on kinetics (Fayon). In a direct lead-up to this project, Ph.D graduate Kalin McDannell examined the implications of our previous work related to trappng of helium in defects and pores, using cumulative-heating analysis of a suite of slowly cooled apatites. In addition, Darwin Janes joined the lab group to complete M.S. research on electron-beam techniques might be used to characterize defect density in apatite. Work on this new project started in earnest in 2018. Funded by the Tectonics Program of the U.S. National Science Foundation.

Completed Projects

Lhasa Block Top to Bottom--Lithospheric Evolution of Asia's Leading Edge

Together with a large group of colleagues at other institutions, we have been using the Lhasa Block in southern Tibet as a natural laboratory to examine crustal evolution of a convergent margin across the transition from convergence to collision. We wish to examine how the early history of a convergent margin can impact later development of the collisional margin, integrating data from studies in geochemistry, geochronology, paleoelevation studies, seismology, tectonics, and thermo-mechanical modeling. This multidisciplinary five-year project, funded by the Continental Dynamics Program of the U.S. National Science Foundation, involves a number of investigators from institutions in the U.S., China, and Europe. The PIs include Zeitler and Anne Melzer at Lehigh, Don Depaolo (Project Coordinator) at Berkeley, An Yin and Mark Harrison at UCLA, David Rowley at Chicago, David Shuster at the Berkeley Geochronology Center and Berkeley, Frederic Herman at ETH in Zurich, and Mo Xuanxue, Zhidan Zhao, and Di-cheng Zhu at China University of Geosciences. Field work started in May 2012. Jen Schmidt here at Lehigh worked on thermochronological aspects of this project as part of her Ph.D. dissertation and is currently preparing these results for publication.

Evolution of the Hangay Mountains in North-Central Mongolia

This large project was a collaboration with Anne Meltzer, Bruce Idleman, and Dork Sahagian at Lehigh, Karl Wegmann at North Carolina State (Karl is lead PI for the whole project), Rick Carlson at DTM, Page Chamberlain at Stanford, and colleagues from the Mongolian Institute of Science and Technology and also the Center of Astronomy and Geophysics at the Mongolian Academy of Sciences. Lenny Ancuta and Kalin McDannell here at Lehigh are working on their Ph.D. degrees as part of this project, on basalt geochemistry and geochronology, and thermochronology. Our goal was to use seismology, geomorphology, geochronology and themochronology, paleo-elevation studies, and geochemistry and petrology to understand the timing and origin of the enigmatic Hangay Mountains, a broad domal region south of the Baikal rift that reaches elevations of 4000 meters. This project started in 2011, and was funded by the Continental Dynamics Program of the U.S. National Science Foundation.

Helium Solubility and Diffusion Kinetics in Apatite and Zircon

Interest in (U-Th)/He dating has blossomed due to the low-temperature sensitivity of helium diffusion in apatite and other accessory minerals like zircon. However, helium diffusion is complicated by accumulation of radiation damage: damage zones appear to act as internal traps for helium, having the net effect of increasing helium retentivity. Contrary to the common assumption that alpha-recoil damage is responsible for this phenomenon, we hypothesize that the much more rare fission-track damage might in fact be an important controlling factor as well. Eva Enkelmann and I have been testing this idea through a series of diffusion experiments in samples in which alpha damage has been annealed and varying levels of fission-track damage have been artificially induced. Work on this project has also branched into studies of He solubility in apatite, in collaboration with Bruce Watson and Jay Thomas at RPI. Supported by the Petroleum Research Fund.

Little Devil's Postpile Revisited: Intercalibration of Themochronometer Kinetics

This project revisits a classic locality in thermochronology, Little Devil's Postpile in Yosemite National Park, where Calk and Naeser conducted their seminal study showing how a younger basalt intrusion had systematically and predictably reset fission-track ages of apatite and sphene in the surrounding Sierra granite. This work was a collaboration between me, Peter Reiners at Arizona, David Shuster at Berkeley Geochronology Center, and Rich Ketcham at Texas; Lehigh Ph.D. candidate Jen Schmidt was also part of the project. This field site offers the opportunity to intercalibrate and assess some 10-15 thermochronometers based on the U-He, Ar-Ar, and fission-track systems. This project was funded by the Petrology and Geochemistry program at the National Science Foundation, and work began in 2011.

U-Th/He Dating and Topographic Evolution of the Appalachians

This long-running project is an investigation of the post-orogenic erosion and topographic history of the Appalachians, using U-Th/He dating of apatite. This work was spearheaded by Ph.D. candidate (and now recipient!) Ryan McKeon, in collaboration with Frank Pazzaglia and Bruce Idleman here at Lehigh. This work was funded by the Tectonics program at NSF.

STEEP - St. Elias Erosion and Tectonics Project

This large multi-investigator project used the St. Elias range in Alaska to investigate the role of glacial erosion in shaping the tectonics of an active orogenic belt, and also what other driving forces and boundary conditions are causing deformation in the region. Lehigh personnel (me, and postdoc at the time Eva Enkelmann) were involved as part of a team of geochronologists that documented the cooling and erosion history of the orogen.

Geodynamics of Indentor Corners

Focused on the eastern end of the Himalaya-Tibet collision zone, this large multidisciplinary study looked at the complex 4D deformation near a plate edge during collision, at all scales: locally, to see if the metamorphic massif and mountain Namche Barwa is an erosionally induced "tectonic aneurysm" as we proposed for Nanga Parbat; regionally, to look at the importance of erosional mass removal in the accommodation of collisional convergence; and margin-wide, to understand the reponse of the entire lithosphere to plate-edge dynamics. Based at Lehigh and also involving Anne Meltzer and her seismology research group, the project includes investigators from a number of universities. Funded by NSF-Continental Dynamics. Work on this project is largely complete and we are in the process of finishing final publications.

Recent and Representative Publications

McDannell, K.T., Zeitler, P.K., and Idleman, B.D., 2018. Relict topography within the Hangay Mountains in central Mongolia: Quantifying long-term exhumation and relief change in an old landscape. Tectonics 37, 1-28, DOI: https://doi.org/10.1029/2017TC004682.

McDannell, K.T., Zeitler, P.K., and Scheider, D.A., 2018. Instability of the southern Canadian Shield during the late Proterozoic. Earth and Planetary Science Letters, 490, 100-109, DOI: https://doi.org/10.1016/j.epsl.2018.03.012.

Ancuta, L.D., Zeitler, P.K., Idleman, B.D., and Jordan, B.T., 2018. Whole-rock 40Ar/39Ar geochronology, geochemistry, and stratigraphy of intraplate Cenozoic volcanic rocks, central Mongolia. Geological Society of America Bulletin, 130, 1397-1408, DOI: https://doi.org/10.1130/B31788.1.

McDannell, K.T., Zeitler, P.K., Janes, D.G., Idleman, B.D., and Fayon, A.K., 2018 (available online 5 December, 2017). Screening apatites for (U-Th)/He thermochronometry via continuous ramped heating: He age components and implications for age dispersion. Geochimica et Cosmochimica Acta, 223, 90-106, DOI: 10.1016/j.gca.2017.11.031.

Idleman, B.D., Zeitler, P.K., and McDannell, K.T., 2018 (available online 17 November, 2017). Characterization of helium release from apatite by continuous ramped heating. Chemical Geology, 476, 223-232, DOI: 10.1016/j.chemgeo.2017.11.019.

Garcia, V.H., Reiners, P.W., Shuster, D.L., Idleman, B.D., and Zeitler, P.K., 2017 (available online August 15, 2017). Thermochronology of sandstone-hosted secondary Fe- and Mn-oxides near Moab, Utah: Record of paleo−fluid flow along a fault. GSA Bulletin, 130(1-2), 93-113, DOI: 10.1130/B31627.1.

Zeitler, P.K., Enkelmann, E., Thomas, J., Watson, B., and Ancuta, L.D., 2017 (available online 10 April, 2017). Solubility and trapping of helium in apatite. Geochimica et Cosmochimica Acta, 209, 1-8, DOI: 10.1016/j.gca.2017.03.041.

Sahagian, D., Proussevitch, A., Ancuta, L.D., Idleman, B.D., and Zeitler, P.K., 2016. Uplift of central Mongolia recorded in vesicular basalts. Journal of Geology, 124, 435-445, DOI: 10.1086/686272.

Schmidt, J.L., Zeitler, P.K., Pazzaglia, F.J., Tremblay, M.M., Shuster, D.L., and Fox, M., 2015. Knickpoint evolution on the Yarlung River: Evidence for late Cenozoic uplift of the southeastern Tibetan plateau margin. Earth and Planetary Science Letters, http://dx.doi.org/10.1016/j.epsl.2015.08.041.

Tremblay, M.M., Fox, M. Schnidt, J.L., Tripathy-Lang, A., Wielicki, M.M., Harrison, T.M., Zeitler, P.K., and Shuster, D.L., 2015. Erosion in southern Tibet shut down a ~10 Ma due to enhanced rock uplift within the Himalaya, Proceedings of the National Academy of Sciences, 112(39), 12030-12035, doi: 10.1073/pnas.1515652112.

Zeitler, P.K., Koons, P.O., Hallet, B., and Meltzer, A.S., 2015. Comment on “Tectonic control of Yarlung Tsangpo Gorge revealed by a buried canyon in Southern Tibet.” Science, 349(6250):799, doi:10.1126/science.aaa9380.

Zeitler, P.K. 2014. U-Th:He Dating. In Rink, W.J. and Thompson, J. eds., Encyclopedia of Dating Methods, Springer, 1-14. doi: 10.1007/978-94-007-6326-5_131-1.

Zeitler, P.K., Meltzer, A.S., Brown, L., Kidd, W.S.F., Lim, C., and Enkelmann, E., 2014. Tectonics and topographic evolution of Namche Barwa and the easternmost Lhasa Block, in Nie, J., Hoke, G.D., and Horton, B., eds., Towards an improved understanding of uplift mechanisms and the elevation history of the Tibetan Plateau. Geological Society of America Special Paper, v. 507, doi: 10.1130/2014.2507(02).

Koons, P.O., Zeitler, P.K., Hallet, B., 2013. 5.14 Tectonic aneurysms and mountain building. In: Shroder, J. (Editor in Chief), Treatise on Geomorphology. Academic Press, San Diego, CA, vol. 5, pp. 318-349, doi: 10.1016/B978-0-12-374739-6.00094-4.

Enkelmann, E., Zeitler, P.K., Garver, J.I., Pavlis, T.L., and Hooks, B.P., 2010. The thermochronological record of tectonic and surface process interaction at the Yakutat-North American collision zone in southeast Alaska. American Journal of Science, 310, 231-260., doi: 10.2475/04.2010.01.

Enkelmann, E., Zeitler, P.K., Pavlis, T.L., Garver, J.I., and Ridgway, K.D., 2009. Intense localized rock uplift and erosion in the St Elias orogen of Alaska. Nature Geoscience, v. 2, no. 5, p. 360-363. DOI: 10.1038/NGEO502.  (pdf)

Finnegan, N.J., Hallet, B., Montgomery, D.R., Zeitler, P.K., Stone, J.O., Anders, A.M., and Liu Yuping, 2008. Coupling of rock uplift and river incision in the Namche Barwa-Gyala Peri massif, Tibet. Geological Society of America Bulletin, v. 120(1/2); p. 142-155; doi: 10.1130/B26224.1.  (pdf)

Stewart, R.J., Hallet, B., Zeitler, P.K., Malloy, M.A., Allen, C.M., and Trippett, D., 2008. Brahmaputra sediment flux dominated by highly localized rapid erosion from the easternmost Himalaya. Geology, v. 36, p. 711-741, doi: 10.1130/G24890A.1.  (pdf)

Sol, S., Meltzer, A.S., Bürgmann, R., Van der Hilst, R.D., King, R., Chen, Z., Koons, P., Lev, E., Liu, Y.P., Zeitler, P.K., Zhang, X., Zhang, J., and Zurek, B., 2007. Geodynamics of the southeastern Tibetan plateau from seismic anisotropy and geodesy. Geology, 35, 563-566 (DOI: 10.1130/G23408A.1).

Koons, P. O., Zeitler, P.K., Chamberlain, C.P., Craw, D., Meltzer, A.S. 2002. Mechanical links between erosion and metamorphism in Nanga Parbat, Pakistan Himalaya. American Journal of Science, 302, 749-773.  (pdf)

Zeitler, P. K., A. S. Meltzer, P. Koons, D. Craw, B. Hallet, C. P. Chamberlain, W. Kidd, S. Park, L. Seeber, M. Bishop, J. Shroder, 2001. Erosion, Himalayan geodynamics, and the geology of metamorphism. GSA Today, 11, 4-8.  (pdf)

Zeitler, P.K., Koons, P.O., Bishop, M. L., Chamberlain, C.P., Craw, D., Edwards, M.A., Hamidullah, S., Jan, M.Q., Khan, M.A., Khattak, M.U.K., Kidd, W.S.F., Mackie, R.L., Meltzer, A.S., Park, S.K., Pecher, A., Poage, M.A., Sarker, G., Schneider, D.A., Seeber, L., and Shroder, J., 2001. Crustal Reworking at Nanga Parbat, Pakistan: Metamorphic consequences of thermal-mechanical coupling facilitated by erosion. Tectonics, 20, 712-728.  (pdf)

Zeitler, P.K., Chamberlain, C.P., and Smith, H.A., 1993. Synchronous anatexis, metamorphism, and rapid denudation at Nanga Parbat (Pakistan Himalaya), Geology, 21, 347-350.  (pdf)

Cerveny, P.F., Naeser, N.D., Zeitler, P.K., Naeser, C.W. and Johnson, N.M., 1988. History of uplift and relief of the Himalaya over the past 18 Ma - Evidence from fission-track ages of detrital zircons from sandstones of the Siwalik Group, in K. Kleinspehn and C. Paola, eds., New Perspectives in Basin Analysis, Univ. Minnesota Press, p. 43-61.  (pdf (10MB!))

Zeitler, P.K., 1987. Argon diffusion in partially outgassed alkali-feldspars: Insights from ⁴⁰Ar/³⁹Ar analysis. Chemical Geology (Isotope Geoscience Section). 65, 167-181.  (pdf)

Zeitler, P.K., Herczeg, A., McDougall, I., and Honda, M., 1987. U-Th-He dating of Durango fluorapatite: a potential thermochronometer. Geochimica et Cosmochimica Acta. 51, 2865-2868.