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http://cornellcollege.edu/geologyhttp://cornellcollege.edu/geologyhttp://cornellcollege.edu/geologyhttp://cornellcollege.edu/geology

View of the Southern Alps, New Zealand, February 2010

FFFFROMROMROMROM TTTTHEHEHEHE CCCCHAIRHAIRHAIRHAIR Dear Geology Alums,

Things are moving along well in the department since the last edition of SPARKS. After his and Ellen’s time in Mexico, Paul has resumed his occupancy of the uppermost floor of the repository where he continues to work independently and with students. And six years after Paul retired, Emily is up for tenure in March. In November, the department hosted Dr. Karl-Heinz Wyrwoll, a geography professor from the University of Western Australia and collaborator with both Ben and me on a variety of Australian research projects. Dr. Wyrwoll, who was joined by his wife Karen, taught a class titled “Ocean-Atmosphere Interactions” as a Presidential Fellow, delivered a Science Interest Group lecture on the evolution of the Australian monsoon, and gave a talk to the geology students about his research in China. It was a rare treat to have such a delightful, engaged, and well-

respected colleague join us, if only for a few short weeks.

I am delighted to report that we continue to have large enrollments and lots of interest in geology. We have waitlists for Mineralogy, and are buying new microscopes again in order to meet this demand. As you will read in this issue, geology students are conducting a record number of research projects now that such experiences are required for the major. Overseeing this many independent studies has certainly kept us on our toes, but we’re delighted to be able to provide such valuable experience. And in keeping with this empha-sis on research, we have all been busily writing letters of recommendation in support of student applications for off-campus summer internships. Several rising juniors and rising seniors are hoping to participate in National Science Foundation Research Experiences for Undergraduates, prestigious fellowships that several of our students have recently engaged in. In fact, I just received a flyer announcing NSF REU opportunities at the University of Minnesota and was delighted to see that it was adorned with a picture of our own Elizabeth Erickson who had studied lake histories in the Limnological Research Center at the UM

last year.

The plants in Ben’s rock garden are now settled in and have transformed the front of Nor-ton Hall. The upstairs classrooms are undergoing some minor revision this summer in order to allow us to teach 25 students in each, a move that is welcomed by the College as it will loosen increasingly tight classroom space as we move closer to an eight-block aca-demic year, down from the traditional nine blocks. Other than that, all is pretty much the

same as it ever was.

We continue to hear from many of you, and we can’t tell you how much we enjoy being able to follow the trajectories of your professional and personal lives. We love to hear

your news so please drop us a line or, better yet, drop in to say hello.

Best,

Rhawn

Rhawn

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Name ____________________________________________ Cornell Class ________

Graduate Degree(s):

University __________________________________________ Year______________

University __________________________________________ Year______________

Home Address

_____________________________________________________________________

_____________________________________________________________________

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Professional and other Activities

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Note: If you know the whereabouts of any of the graduates whose addresses are marked “unknown” or if you are aware of any changes of address, would you please pass this informa-

tion along to us? Thanks.

Please return to (or e-mail):

Jackie Stewart

Development Office

Cornell College

600 1st Street West

Mount Vernon, IA 52314

[email protected]

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The Geology Department serves students desiring a major or minor in geology. We offer a basic curriculum of upper-level courses which, along with supporting coursework in other sci-ences and mathematics, prepare our graduates for entry-level occupations in government and industry, or for graduate-level education in Geology or Environmental Science at institutions across the country. Our curriculum also prepares students who choose careers in Earth Science teaching. The department offers several block-long field courses in diverse areas around the world. We especially encourage and support independent re-search projects by our students. In concert with several depart-ments across several divisions of the college, we lead Cornell's Environmental Studies Program. Many students have taken ad-vantage of environmental-related research and internship oppor-tunities funded though Geology Department research funds or

the Cornell Fellows program.

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SPRING BREAK TRIPS

GRAND CANYON/DEATH VALLEY 2010 — NEW ORLEANS BAYOU 2011

GEOLOGY OF NEW ZEALAND 2010

GEOLOGY OF NATIONAL PARKS

COLORADO/UTAH 2010

MODERN AND PLEISTOCENE CARBONATE

ENVIRONMENTS 2010

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GEOMORPHOLOGY

BADLANDS/BLACK HILLS 2011


Greetings to all Geology alumni,

The last two years have flown by at the usual hectic place. The literature database I men-tioned in the last newsletter is now complete. With the help of Chelsea Korpanty (’11) I have now compiled coral species occurrence data from reefs existing over the last 125,000 years in the Caribbean, Gulf of Mexico and tropical Western Atlantic. The database com-prises >2500 records drawn from ~ 250 technical journal articles and reports. I am on sab-batical during spring 2011, and one of my projects will be to query the database to explore a number of issues related to whether historical precedents exist for the current catastrophic

decline observed on coral reefs in those regions.

The second project for my sabbatical involves an investigation of the role of the frequency of disturbance by hurricanes in reef coral community assembly. This project began in June 2010 on the island of Curaçao, Netherlands Antilles. Elizabeth Erickson (’11) and Chelsea Korpanty (’11) joined long-time colleague John Pandolfi, his doctoral student Brigitte Som-mer and me for three weeks of fieldwork. Liz and Chelsea both are completing honors the-ses based on projects they developed on the island, and Chelsea returns to Curacao with me in January 2011 to continue fieldwork. I will travel to the U. Queensland, Australia during

March 2011 to analyze data obtained for both of these projects.

There has been quite a run of Cornell College geology majors to excellent graduate pro-grams in paleontology in the last few years. Kelsey Feser (’10) completed her honors thesis based on fieldwork on San Salvador Bahamas and now is ensconced in a Ph.D. program at the University of Cincinnati. Kris Rhodes (’08) is working on a Ph.D. at U. Michigan. Jill Leonard-Pingle (’03) is completing her Ph.D. at Scripps, Amelinda Webb (’05) is working on a Ph.D. at Yale, and Dana Friend (’09) is about to finish her M.S at the University of N. Carolina at Wilmington and plans to pursue a Ph.D. Chelsea Korpanty (’11) is applying to paleontology graduate programs as I write this. The paleontological profession has a bright

future!

In addition to supervising students and conducting my own research, I spent 8 days running a teaching workshop on San Salvador in July 2010. With funding from a Mellon grant to the Environmental Studies program, I helped four faculty colleagues from the departments of English, History and Classical and Modern Languages develop new courses to be taught at the Gerace Research Centre on San Salvador. I am very pleased to be involved with the

expansion of liberal arts courses on the island.

Our elder son, Elijah, graduated from the University of Pennsylvania in May 2010 and now is teaching English in Japan through the JET program. Jonah now is a sophomore in the Tisch School of the Arts at New York University, where he studies film production. Part of

my sabbatical will be spent traveling with Janet to see both of our far-flung boys.

Keep in touch, everyone.

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Greetings to all and Happy 2011,

The past two years have been momentous in numerous ways. I am currently in my 6th year here at Cornell College and will undergo my tenure review in March. If all goes well, I will take a sabbatical next fall and then return to the ranks as an Associate Professor. I participated in a research trip to China in 2009 that led to a new research collaboration and several new projects in which I can involve student researchers. Also, I was on ma-

ternity leave this past fall, and I now have a wonderful son to inspire me.

I continue to make changes in my course offerings, and one of the most exciting new developments for me is the separation of Igneous & Metamorphic Petrology into two courses. Although related, the topics are so different, and it was nearly impossible to cover even the basics of each during one block. By the end of the class we were all (students and professor) completely exhausted. By teaching two courses, I will be able to cover some important topics in more depth, and I will be able to add a substantial hands-on project to each course without re-creating the frenetic pace of the previous all-in-one course. I also look forward to adding a metamorphic petrology field trip to the course; the short trip we take now (to the St. Francois Mountains of southeastern Missouri) high-

lights igneous rocks.

My Geology of the National Parks course is also changing slightly: the name of the course will be Go West: an Introduction to Field Geology, and it will now count as a field-based introduction to the geology major. We hope this draws more students to the course as well as to the major. Although small, this course has been enjoyable in the past two years, with one course to South Dakota (the Black Hills, Badlands) and the next through Colorado (Florissant Fossil Beds National Monument, Great Sand Dunes National Park,

Mesa Verde National Park) and into Utah (Canyonlands).

I continue to involve students in my research. During the summer of 2009, student Nick Tripp worked with me to separate and date titanite grains from mafic dikes, basement gneiss and pegmatites from the ultrahigh-pressure terrane in the Western Gneiss Re-gion, Norway. During 3rd block, 2009, Nick spent about 10 days at the University of Cali-fornia, Santa Barbara, preparing and dating the titanites by thermal ionization mass-spectrometry and laser-ablation ICP-MS. Although the data were not all that we had hoped, the trip was a fantastic experience for Nick, and my UCSB colleagues were highly impressed with him. Last winter, student Natashia Pierce and I spent time at the Univer-sity of Iowa analyzing the whole rock geochemistry of ophiolitic rocks from the North Qaidam Mountains, Qinghai Province, China, for her Geo-485. Natashia continued her work on the ophiolite over the summer (2010), studying microtextures in thin sections of the ophiolite from the ductile detachment zone separating the ophiolite from an ultrahigh-pressure terrane. This year, Natashia has spent two blocks interning with the Iowa Geo-logical Survey, mapping structures at the Devonian Fossil Gorge and surrounding area on

Coralville Lake. For this internship, she received a prestigious Cornell Fellows award.

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Rising junior Chelsea Nissen worked with me last July on eclogites from the ultrahigh-pressure terrane in the North Qaidam Mountains. For this work we travel to the University of Wisconsin, Madison, to use their electron micro-probe for chemical analysis of the minerals in the eclogite to estimate the pressures and temperatures the eclogite experienced during subduction and exhumation. Chelsea is continuing that project this year as her Geo-485, and she is joined in that work by classmate Robin Drucker, also for her Geo-485. Robin and I received an R.J. McElroy Trust Student Research Fund award to

pursue this research.

Again, we are happy to report the continuation of larger numbers of geology majors. I taught Mineralogy to 15 again this year and had a waiting list be-sides! We would love to hear from you, so drop us a line and let us know

where you are and what you are up to.

Cheers,

Emily

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Greetings,

I am pleased to be included in this issue of Sparks. Here is a brief rundown on my activi-ties since my retirement in 2005. I spent the first year doing research on fire-cracked rock and pottery sherds that were excavated by Cornell College students in John Doer-shuk’s Field Archaeology at the Dows Preserve (across the river from the Pal). That led to a coauthored publication in the Journal of Iowa Archaeology in 2009, including Cornell student, Julia Clark (’06). I also continued my research on the petrography of some Sho-shonean pottery that I collected from the Snake River in Idaho, way back when I was a high school student. The stuff sat in boxes for 30+ years, until I finally decided I ought to

do something with it.

The research was put on hold, because in January 2007 Ellen and I left the country to serve a three-year mission for our church in Mexico City. We were directors of a large visitor’s center (ca. 60,000 visitors annually). We survived the frightening traffic, the perpetual noise and the choking air pollution of that monstrous city, and we developed a great love for our Mexican brothers and sisters. Though I didn’t have time for geology, Ellen and I did climb Volcan Nevado, a very large stratovolcano which is located a few hours west of Mexico City. We hiked around the rim of a giant pond-floored caldera. We topped out at about 14,500 feet a.s.l. We were somewhat surprised at not suffering altitude sickness. But then, Mexico City sets at 7500 feet a.s.l., so I guess we were accli-matized. Being accustomed to alpine hiking in the northwest Rockies, we were amazed to discover how dry it is above timberline there—no snow, no streams, and sparse vege-tation (scattered cactus, clumps of grass, and very few flowers). We also visited several archaeological sites in and around Mexico City (Teotihuacan five or six times). I got to know one of the site archaeologists at Teotihuacan, from whom I learned a lot about the

fascinating history of that great city.

We returned to Iowa in February 2010. After chipping six inches of solid ice off the roof line of our house, and otherwise reacquainting myself with the Iowa winter, I returned to the office at Norton (I have a really neat work space in the upper level of the repository). I finished my work on the Shoshonean pottery, and I have submitted a manuscript to a journal for publication. Last summer I supervised a Cornell student (Nic Slater ’12) on more research on the pottery from the Dows Preserve. He will present a paper in April at

a meeting of the Central States Archaeological Society.

Ellen and I are both in good health, and we are enjoying our children and grandchildren. We are applying to serve another mission. Our plans are to leave in early September, this time for only a year and half. We have no idea where they might send us. We’d love to go to Latin America again, but really doesn’t matter to us. If your travel plans bring you through Iowa this spring or summer, we would love to see you. Thanks for all you do for

Cornell geology. It is a great department!

Best regards,

Paul and Ellen

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Dear Cornell Alums,

Hello from Norton. As always, I remain wrapped up with teaching and research which these days is focused almost entirely on caves in northern Australia. I visited the Kimberley of Western Australia region in June 2009 and will return again this summer with two students to collect more stalagmites. The caves are hot (90+˚F), tight, some have snakes, and one even held a big lizard that jumped out to say hello when we were surprisingly far from the en-trance. Nonetheless, the stalagmites have yielded results that I find fascinating. One of my research students has found that some of the stalagmites may allow us to reconstruct hurri-cane activity over the past several thousand years with amazing accuracy and precision. Using uranium-thorium dating methods, we are able to date mud layers (that we think are flood deposits from passing hurricanes) with errors of only ±1 year over the past century. I have a proposal in review at the National Science Foundation to continue this work. And the research of several other students (going back two or three years) on other stalagmites from the same caves has revealed that these samples can track the intensity of Australian monsoon rainfall over the past 9,000 years and that variations in rainfall appear to be linked to El Nino events and even subtle changes in the output from the Sun! In the up-coming days, I am

submitting a manuscript on this work that includes four student co-authors.

My field class to New Zealand is undergoing continuous revision. We still start the trip with a week at the Takaka field station and then head south to Franz Josef glacier, but on this last trip. we spent several days in Hokitika in the heart of jade country on the central west coast of the South Island where we (coarsely) mapped a large area along the Alpine Fault. Doing so allowed us to discover some beautiful places I’d never seen, as well as to experience some amazing geology. Next year, I am thinking of heading even further south, perhaps to the Fjordlands. I keep talking about hosting a trip for alumni and hope to actually follow through

on this idea in the years to come.

My family is doing well. Jen is writing chapters for Lonely Planet guides to Orlando (where we just visited the Harry Potter-themed portion of Universal Studios, a destination not to be missed by fans of the books) and the Grand Canyon. Anna is now in 5th grade and wrapped up in her books, tap and ballet dancing, piano lessons, and friends. Perpetually happy Harper, though only in 2nd grade, is proving to be a talented artist, as well as a devoted

younger sister.

I love hearing from students I’ve know and those from before my time, so please send me an

email if you have the time ([email protected]).

Best,

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In May 2010, the Geology of National Parks course crossed Iowa and Ne-braska to explore Colorado and parts of neighboring states Utah and New Mexico. The class was small, just 7 students and Professor Emily Walsh, but it was very diverse—three of the participating students were exchange stu-dents from Japan and South Korea. They provided the rest of us with a won-derful perspective on our vast and scenic West and the National Park system that so many of us take for granted. Because we drove and camped on our 2-week trip, we got to know each other well, and although we had students with varying levels of geology, we all got along. We started the trip with a full day’s drive into eastern Colorado and were hiking at Florissant Fossil Beds National Monument the next day. From there we continued on to Great Sand Dunes National Park (where it snowed on us), the Rio Grande Rift south of Taos, Mesa Verde National Park, Canyonlands National Park, Arches National Park, and back through Colorado by way of Durango. The highlight for every-one was Canyonlands National Park, where we took a 6-mile hike to the Nee-dles and saw very few other people (the weather was also gloriously warm and sunny there). Our campground in Utah (Devil’s Canyon National Forest Campground) was also the favorite, even though it had only pit toilets and the water had not yet been turned on! We returned to campus feeling re-freshed and like we had learned and seen a great deal, and I am determined

to take another trip back to the area in the future.

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Dr. Karl-Heinz Wyrwoll, senior lecturer in the School of Earth and the Environ-ment at the University of Western Australia, served as a Cornell Presidential Fellow in geology and environmental studies during November 2010 and taught a class entitled “Ocean-Atmosphere Interactions”. Dr. Wyrwoll com-bines geomorphological field techniques with computer simulations to better understand the evolution of the Australian monsoon over the past several hun-dred thousand years. He has collaborated with Ben on a coral-based study of last interglacial dynamics of Western Australia paleoceanography, and with

Rhawn on a stalagmite-based study of the Australian monsoon.

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Karl-Heinz Wyrwoll et al. (2007) Sensitivity of the Australian summer monsoon to tilt and precession forcing. Quaternary

Science Reviews, v. 26, p. 3043–3057.

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The Geology Club's 2010 annual spring break trip took Cornell students, the majority of whom were geology major or minors, to Death Valley and the Grand Canyon. A flight to Las Vegas set the students in the heart of the warm climate

they were to spend the next week and a half enjoying.

Beginning with Death Valley before travelling to the Grand Canyon, the Geology Club spent the days hiking and exploring to gain an understanding of the geol-ogy of the park and similar landforms. We took a hike up Mosaic Canyon to see the smoothed chert walls. On another day, students hiked through Golden Can-

yon and witnessed the multi-colored splendor that makes up the rocks.

The Grand Canyon provided an equally amazing trip for the students as the hiking was great, and the sunrises were gorgeous. We found hidden arches known as the Four Sisters as well as the hideaway for the park’s architect, giving a panoramic view of the entire park. Another day, the entire crew hiked partway down into the canyon and back up to see more aspects of the canyon not seen from the rim. However, we were snowed out and, after having to sleep

in the vans for two nights during a blizzard, we moved on to warmer weather!

Students greatly enjoyed this trip and will remember the good and the bad for times to come! Many have expressed their desires to return to both parks,

either individually or as a group to explore further than before!

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The Geology Club's 2011 spring break trip took nine Cornell students to New Or-leans, Louisiana. New Orleans is situated on the banks of the Mississippi River near the Gulf of Mexico. In the fall of 2005, Hurricane Katrina devastated the city after the failure of the Federal levee system. The storm resulted in flooding of 80% of New Orleans, with some parts under more than 15 feet of water! Further, the very system of levees and river channels built to prevent flooding caused drainage prob-lems as water was trapped within the city. Six years later, the destruction still per-vades the scenery. A major victim of the storm and land-use practices is the devas-tation of the wetlands, which would have naturally served as a buffer zone from the

hurricane.

This devastation of the Mississippi River Delta inspired us to collaborate with Bayou Restore and Common Ground Relief, two non-profit organizations focused on wet-lands restoration and conservation. We took on an arduous sixteen-hour caravan drive and spent just over one week experiencing southern Louisiana and volunteer-ing in various projects. To experience the culture, we met with geologists at a Chev-ron company to learn about deep sea oil drilling, took an airboat ride in alligator inhabited swamp land, toured the Destrehan Plantation, and went to a crawfish fry. We also explored the sites and entertainment of New Orleans from the French Quar-

ters to Magazine Street.

Most of our time was dedicated to the volunteering activities. We were given the opportunity to work with many wonderful and passionate people across a broad spectrum of wetlands projects. Our contributions include building a Rain Garden Project in the Lower Ninth Ward, exterminating the invasion of Chinese Tallow dis-placing the native cypress trees, planting trees around the city, and helping set up a Wetlands Education site at a local elementary school. On our final day of physical labor, we planted trees at the Woodlands Conservancy to restore the bottomland

hardwood forest.

All told, we had an amazing trip! In the past, the Geology Club has explored geologi-

cal wonders, but we are all very happy that this year we tried to give back. New Or-

leans is rich with history and culture and is a great place to learn about wetlands

conservation issues.

2009-2011


2010 Majors: Nick Tripp, Kelsey Feser, Becca Ellerbroek

2011 Majors: Chelsea Korpanty, Elizabeth Erickson, Natashia Pierce, Nicholas

Campbell, Hailey Goetschius, Megan Denner

2011 Minors: Joseph Dowdy, Kristina Ottens, Emily Krauter

Student Awards and HonorsStudent Awards and HonorsStudent Awards and HonorsStudent Awards and Honors

Herbert Hendriks AwardHerbert Hendriks AwardHerbert Hendriks AwardHerbert Hendriks Award (to the top senior geology major)

2010: Kelsey Feser

2011: Elizabeth Erickson

WilliamWilliamWilliamWilliam H. Norton Geology PrizeH. Norton Geology PrizeH. Norton Geology PrizeH. Norton Geology Prize (to the top junior geology major)

2010: Elizabeth Erickson and Chelsea Korpanty

2011: Robin Drucker and Chelsea Nissen

Paul Garvin Award Paul Garvin Award Paul Garvin Award Paul Garvin Award (to the top sophomore geology major)

2010: Robin Drucker and Chelsea Nissen

2011: Michael Barthelmes

Gene Hinman Geology Prize Gene Hinman Geology Prize Gene Hinman Geology Prize Gene Hinman Geology Prize (for excellence in field research)

2010: Nic Slater

2011: Chelsea Korpanty

Hendriks Student Research FundHendriks Student Research FundHendriks Student Research FundHendriks Student Research Fund

2010: Nick Tripp

2011: Daniel Cleary, Michael Barthelmes, Nic Slater, Chelsea Korpanty, Elizabeth

Erickson

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SSSS T U D E N TT U D E N TT U D E N TT U D E N T R E S E A R C HR E S E A R C HR E S E A R C HR E S E A R C H

NICHOLAS TRIPP, ‘10NICHOLAS TRIPP, ‘10NICHOLAS TRIPP, ‘10NICHOLAS TRIPP, ‘10

Titanite U-Pb Geochronology in the North-Central Western Gneiss Region, Norway

KELSEY FESER, ‘10KELSEY FESER, ‘10KELSEY FESER, ‘10KELSEY FESER, ‘10

Mitigating the Effects of the Shifting Baseline Syndrome by Utilizing the Benthic Mollus-can Death Assemblage

CHELSEA KORPANTY, ‘11CHELSEA KORPANTY, ‘11CHELSEA KORPANTY, ‘11CHELSEA KORPANTY, ‘11

Efficacy of the Curaçao Marine Park: A Pleistocene Perspective

NATASHIA PIERCE, ‘11NATASHIA PIERCE, ‘11NATASHIA PIERCE, ‘11NATASHIA PIERCE, ‘11

Tectonic History of the North Qaidam Ophiolite, Qinghai Province, China

EL IEL IEL IEL I ZABETH ERICKSON, 11ZABETH ERICKSON, 11ZABETH ERICKSON, 11ZABETH ERICKSON, 11 Using Epibiont Successional Patterns to Determine Mode of Accumulation of Late Pleistocene

Fossil Reefs

HAILEY GOETSCHIUS , ‘11HAILEY GOETSCHIUS , ‘11HAILEY GOETSCHIUS , ‘11HAILEY GOETSCHIUS , ‘11

Beach Dynamics of San Salvador

KRIST INA OTTENS, ‘11KRIST INA OTTENS, ‘11KRIST INA OTTENS, ‘11KRIST INA OTTENS, ‘11 A Comparison of Analyses of Drilling Predation on Fossil Bivalves Using Different Sampling

Methodologies: Bulk Sampling vs. Taxon-Specific Sampling & the Role of Collector Expertise

CHELSEA NISSEN, ‘12CHELSEA NISSEN, ‘12CHELSEA NISSEN, ‘12CHELSEA NISSEN, ‘12 Pressure-Temperature Estimates of Eclogites in the North Qaidam Ultrahigh-Pressure Meta-morphic Belt in China

MEGAN DENNER, ‘11MEGAN DENNER, ‘11MEGAN DENNER, ‘11MEGAN DENNER, ‘11 Combined Stalagmite and Limpet-Based Holocene Paleloclimate Reconstructions from Coastal

Portugal

N ICOLAS SLATER, ‘12NICOLAS SLATER, ‘12NICOLAS SLATER, ‘12NICOLAS SLATER, ‘12 A Quantitative Analysis of Ceramic Thin Sections at Site 13LN323, Palisades-Dows State Pre-

serve, Linn County, Iowa

EL IZABETH GREAVES, ‘12EL IZABETH GREAVES, ‘12EL IZABETH GREAVES, ‘12EL IZABETH GREAVES, ‘12

Monsoon Variability Preserved in Australian Stalagmites During the Early Holocene

N ICHOLAS CAMPBELL, ‘11NICHOLAS CAMPBELL, ‘11NICHOLAS CAMPBELL, ‘11NICHOLAS CAMPBELL, ‘11

Reconstructing Tropical Cyclone Frequency Using Mud Layers in Speleothems

ROBIN DRUCKER, ‘12ROBIN DRUCKER, ‘12ROBIN DRUCKER, ‘12ROBIN DRUCKER, ‘12 Using Ultrahigh-Pressure Eclogites to Reconstruct the Tectonic Past of the North Qaidam

Mountains, China


At over 60,000 km2, the Western Gneiss Region of the Scandinavian Caledonides represents one of the largest ultrahigh-pressure (UHP) ter-ranes in the world. Such UHP terranes provide a window to unique geo-logic processes that are enigmatic due to the subduction of continental crusts to depths >90 km in some cases. The Caledonides are the prod-uct of four distinct orogenic events: Finnmarkian, Taconian, Caledonian, and Scandian. Before or perhaps during the Caledonian orogeny, mafic dikes intruded many of the nappes and were subsequently deformed during the Caledonian and Scandian orogenies. Due to the deformation of the nappes, correlation in many areas has been difficult. U-Pb geo-chronology was performed on titanite grains found in mafic dikes as well as pegmatites and basement rock using both Thermal Ionization Mass Spectrometry (TIMS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) analyses. Our goal was to provide age constraints for the igneous intrusions and to see whether the titanites had recorded the same metamorphic events as the rest of the rocks in the area. The resulting ages from the TIMS analysis represent a mixture of younger and older metamorphic events, indicating that the titanite grains are likely zoned and have a complex internal structure. LA-ICP-MS results provided a wide range of lower intercept discordia ages (465-354 Ma) and rather geologically meaningless upper intercept ages. The re-sults reveal that the mafic dikes in the study area underwent the same resetting events as the whole WGR and are not able to provide better

constraints for the timing of emplacement of the dikes.

Titanite UTitanite UTitanite UTitanite U----Pb Geochronology in the NorthPb Geochronology in the NorthPb Geochronology in the NorthPb Geochronology in the North----Central Western Gneiss Region, Central Western Gneiss Region, Central Western Gneiss Region, Central Western Gneiss Region,

NorwayNorwayNorwayNorway

Nicholas Tripp, Emily O. Walsh, Andrew Kylander-Clark

“Rocks are records of events

that took place at the time they

formed. They are books. They

have a different vocabulary, a

different alphabet, but you

learn how to read them.”

-John McPhee

2009-2011

Benthic marine faunas are currently experiencing rapid shifts in community structure which are already having deleterious effects on marine ecosystems. Since many systematic surveys of marine commu-nities occurred after those communities had been disturbed, our knowledge of “what is natural” is in-complete: a phenomenon that has been termed the “shifting baseline syn-drome.” Since ecological restoration efforts require an understanding of previ-ous community states, alternative methods for delineating pre-disturbance community states are es-sential. In this study we apply analyses of life vs. death assemblage compo-sition of communities that have undergone differing histories of disturbance. Live and dead mollusks obtained from transects constructed in two bays adjacent to San Salvador Island, Bahamas, were identified and community structure was compared. In Snow Bay, where little anthropogenic disturbance has occurred, diversity and relative abundance be-tween life and death as-semblages was more simi-lar than the same metrics for life and death assem-blages collected from Bone

Fish Bay, where develop-ment has resulted in elevated levels of fecal coliform bacteria. We conclude that the changes to the benthic molluscan communities resulting from develop-ment in Bone Fish Bay have not yet been re-corded by the attendant death assemblage. Thus, molluscan death assem-blages may be used as proxies for pre-disturbance community states in environments that have already been degraded. ********Awarded Best Presen-tation by an Undergradu-ate Student, North-Central Section and South-Central

Section, Geological Soci-ety of America Joint Meet-ing, April, 2010.

Mitigating the Effects of the Shifting Baseline Syndrome

by Utilizing the Benthic Molluscan Death Assemblage

Kelsey Feser

"We are like a

judge confronted by

a defendant who

declines to answer,

and we must deter-

mine the truth

from the circum-

stantial evidence."

-Alfred Wegener


As global climate

change persists, anthro-

pogenic impacts will

continue to exacerbate

current environmental

degradation, particularly

to coral reef ecosys-

tems. To mitigate this

critical situation, coral

reef conservation efforts

have focused on the

development of effec-

tive marine protected

areas (MPAs). However,

successful ecological

conservation and resto-

ration require an under-

standing of previous

community states –

unaffected by anthropo-

genic impacts - to serve

as a basis for compari-

son. This study pur-

sues a paleoecological

approach to under-

standing the commu-

nity structure of Carib-

bean coral reefs prior

to human impacts.

Results are utilized to

assess the efficacy of a

developing marine

protected area in Cura-

çao, Netherlands Antil-

les. Systematic cen-

suses of Late Pleisto-

cene fossil coral reefs

were compared to cen-

suses of modern reef

sites within and out-

side the Curaçao Ma-

rine Park. The Late

Efficacy of the Curaçao Marine Park: A Pleistocene Perspective Efficacy of the Curaçao Marine Park: A Pleistocene Perspective Efficacy of the Curaçao Marine Park: A Pleistocene Perspective Efficacy of the Curaçao Marine Park: A Pleistocene Perspective

Chelsea Korpanty and Benjamin Greenstein

Pleistocene coral reefs

preserve communities

with higher abundance

and diversity than the

modern sites. Modern

reefs outside park

boundaries support a

distinctly different

community structure

than both Pleistocene

reefs and modern

reefs located within

park boundaries. Addi-

tionally, modern reefs

situated within the

park show a greater

community resem-

blance to the Pleisto-

cene reefs. We con-

clude that the nascent

Curaçao Marine Park –

lacking active manage-

ment and definitive

conservation regula-

tions – provides some

degree of protection to

modern reefs within its

borders. Furthermore,

the study illustrates

the feasibility of utiliz-

ing paleoecological

studies to inform is-

sues related to marine

conservation.

2009-2011

The North Qaidam Ophio-lite provides insight into the mechanisms that formed the rocks of the Tibetan Plateau before its uplift through the Ceno-zoic India-Eurasia colli-sion. The ophiolite, juxta-posed and folded with an ultrahigh-pressure (UHP) terrane across the Luili-angshan Detachment Zone, separates the two major terranes in the region, the Qaidam and Qilian blocks. Two end-member models exist for the creation of the North Qaidam Ophiolite: (1) the closing of a single ocean through the collision of small continental masses with the Eurasian conti-nent above a single north-facing subduction zone, and (2) the closing of several oceans through the collision of larger continental blocks, such as the Qaidam and Qilian blocks, through multiple north-and south-facing subduction zones before collision of the entire area with the Eurasian conti-nent. Because the former model predicts the clos-ing of a single ocean, its ophiolite should record the geochemical signa-tures of a mid-ocean ridge basalt (MORB) envi-ronment. The multiple

ocean closure of the latter model should demonstrate geochemi-cal signatures in the ophiolite, which evi-dence a supra-subduction zone (SSZ) environment such as a backarc, intra-arc, or

forearc basin.

Previous geochemical research records evi-dence of both MORB and SSZ environments in the North Qaidam Ophiolite. Zircons from the ophiolite show MORB signatures, whereas whole rock geochemical analyses of the ophiolitic rocks re-veal signatures of an SSZ environment. To determine which model best describes the crea-tion of the North Qaidam Ophiolite, we analyzed the petrography and

whole rock geochemistry of 10 ophiolitic rocks. Petrographic analysis indicated pyroxene crys-tallization prior to plagio-clase crystallization, which suggests an SSZ environment; whereas major element oxides revealed signatures of MORB environments. Trace element analysis revealed a smaller ratio of the incompatable immobile element Y to the compatible element Cr, and less V than Ti, which indicate an SSZ environment as well. We concluded that the North Qaidam Ophiolite was formed in a backarc basin because of the presence of both MORB and SSZ signatures, which best matches the model of multiple ocean

closure.

Tectonic History of the North Qaidam Ophiolite, Qinghai Tectonic History of the North Qaidam Ophiolite, Qinghai Tectonic History of the North Qaidam Ophiolite, Qinghai Tectonic History of the North Qaidam Ophiolite, Qinghai Province, China Province, China Province, China Province, China

Natashia Pierce, Emily Walsh, Carrie Menold


Coral colony orientation data obtained from Late Pleistocene reef coral as-semblages preserved on Curaçao, Netherlands Antil-les, Great Inagua and San Salvador Islands, Baha-mas, indicates that the same gradient in hurricane frequency observed today also was present during Late Pleistocene time. We conduct an independent test of this hypothesis by examining the successional patterns exhibited by epibi-onts that grew on coral colonies during a distinct reef-building event that is spectacularly preserved in the upper Hato Unit of the Lower Terrace Limestone, exposed on Curaçao, Neth-

erlands Antilles.

Corals were removed along vertical transects constructed on replicate leeward and windward fossil reef exposures (total of four sites) on Curaçao. Coral colony samples were taken ap-proximately every 20-40 cm over an average of 5 meters of transect per site. A total of 51 coral samples were obtained for analysis. Thin sections were used to identify epibiont species pre-served in and on corals, quantify their degree of coverage, and elucidate successional patterns preserved on individual

corals.

Using Epibiont Successional Patterns to Determine Mode of Accumulation of Using Epibiont Successional Patterns to Determine Mode of Accumulation of Using Epibiont Successional Patterns to Determine Mode of Accumulation of Using Epibiont Successional Patterns to Determine Mode of Accumulation of

Late Pleistocene Fossil ReefsLate Pleistocene Fossil ReefsLate Pleistocene Fossil ReefsLate Pleistocene Fossil Reefs

Elizabeth Erickson and Benjamin Greenstein

Windward exposures

exhibit sequences of

robust Acropora palmata

colonies with thick epibi-

ont coverage, while lee-

ward exposures exhibit

colonies retaining thinner

encrusting layers with

more sediment fill around

coral colonies. We inter-

pret this difference to be

the result of contrasting

wind and wave energy

regimes. Ongoing analy-

ses of epibiont succes-

sions within each site will

allow for a discrimination

of high versus low distur-

bance frequencies during

accumulation of the fossil

reefs.

The San Salvador Island,

Bahamas, is located within

Hurricane Alley, causing

the island to be passed by

approximately 60 hurri-

canes in over a 100-year

span. The purpose of this

project is to conduct a

comparative multiyear

study, from 1999 to 2010,

of three beaches on San

Salvador that experience

different wave and wind

regimes and examine the

effects that time and pre-

vailing trade winds have on

the length/anatomy of a

beach’s profile, in relation

to its location. For this

study the beaches were

standardized and digital-

ized into a PowerPoint

animation in order to be

compared. Different

factors, such as extreme

weather events

(hurricanes), location

relative to prevailing

winds, and proximity to

rocky headlands are what

influence the beaches

dynamics and consequent

Beach Dynamics of San SalvadorBeach Dynamics of San SalvadorBeach Dynamics of San SalvadorBeach Dynamics of San Salvador

Hailey Goetschius

geomorphology; Rocky

Point beach generally

remains stable, East

Beach is prograding sea-

ward, and Sandy Point

beach is the most dy-

namic system due to its

exposure on the windward

southeast coast of the

island. By looking at these

beaches it can give us

ideas as to the trends of

these beaches and deter-

mine what they may look

like in the future.

2009-2011

Taxon-specific sampling has been used in many studies of drilling gastro-pod predation and is particularly useful for rare taxa. Whether predation metrics from such sam-ples are biased compared to bulk samples, the most widely accepted method of collection for studies of predation, requires test-

ing.

To test for bias, we com-pared analyses of preda-tion in bulk samples and taxon-specific samples collected by a novice and veteran collector using the bivalves Lirophora, Astarte, Cyclocardia, and Glycymeris. The Early Pleistocene lower Wac-camaw Formation was sampled at five localities in southeast North Caro-lina by taxon-specific collection and bulk collec-tion as part of a Research Experiences for Under-graduates program. Vari-ables included body size distribution, valve fre-quency, thickness, size selectivity (measured by correlating drillhole size and prey size), drilling frequency (DF), prey ef-fectiveness (PE), and drillhole site selectivity using Kelley’s (1988) 9-

sector grid. DF equals the number of valves with a complete drillhole divided by half the num-ber of valves (as only one of an individual’s two valves is drilled). PE is defined as the num-ber of incomplete drill-holes divided by the total number of drilling

attempts.

Preliminary results for Holloman Pit show no statistically significant differences in DF and PE between sampling meth-ods or collector exper-tise level for Astarte or Cyclocardia. However, differences between sampling methods for Astarte were statisti-cally significant for body size distribution, valve frequency, thick-ness, and size. Body size distribution, thick-ness, size, and site selectivity were differ-ent for Cyclocardia. There were no statisti-cally significant differ-ences between collec-tors. These differences best reflect shell size variability between the bulk samples and taxon-specific samples. Preliminary results for

Williamson Pit also show no significant differ-ences between exper-tise level for body size distribution, valve fre-quency, thickness, DF, size, and site selectivity. PE was not evaluated as no specimens with in-complete drillholes were collected. Results indi-cate no bias due to ex-pertise level but some size-related differences between sampling meth-ods in variables typically examined in studies of drilling predation. Work on additional sites is in

progress.

A Comparison of Analyses of Drilling Predation on Fossil A Comparison of Analyses of Drilling Predation on Fossil A Comparison of Analyses of Drilling Predation on Fossil A Comparison of Analyses of Drilling Predation on Fossil Bivalves Using Different Sampling Methodologies: Bulk Bivalves Using Different Sampling Methodologies: Bulk Bivalves Using Different Sampling Methodologies: Bulk Bivalves Using Different Sampling Methodologies: Bulk Sampling vs. TaxonSampling vs. TaxonSampling vs. TaxonSampling vs. Taxon----Specific Sampling and the Role of Specific Sampling and the Role of Specific Sampling and the Role of Specific Sampling and the Role of

Collector ExpertiseCollector ExpertiseCollector ExpertiseCollector Expertise Kristina Ottens, Greg Dietl, and Patricia Kelley

For a billion years the patient

earth amassed documents and

inscribed them with signs and

pictures which lay unnoticed and

unused. Today, at last, they are

waking up, because man has

come to rouse them. Stones have

begun to speak, because an ear is

there to hear them. Layers become

history and, released from the

enchanted sleep of eternity, life's

motley, never-ending dance rises

out of the black depths of the past

into the light of the present.

Hans Cloos

<0.5 GPa and <650⁰C up to 1.3 GPa and 725⁰C (Zhang et al. 2009). To better con-strain the tectonic his-tory of the UHP belt, additional eclogites were analyzed petro-graphically and by elec-tron probe microscopy. Eclogite sample 98-14B1 yields the mineral assemblage grt+cpx+bt+qtz, which demonstrates eclogite-facies metamorphis; however, the mineral assemblage does not allow for the estimation of peak pressure condi-tions. Garnets exhibit distinct reaction rims signifying retrogression and using grt-cpx ther-mometer (Krogh, 2000), I found temperatures from 634-675⁰C at pres-sures of 5-13 kbar; this agrees with the third, retrogressed, stage metamorphism as de-fined by Zhang et al (2009).

The Tibetan plateau in Southwestern China is the result of multiple tectonic events. The region is composed of various terranes and tectonically altered zones, including the North Qai-dam ultrahigh-pressure (UHP) metamorphic belt. The belt extends roughly 500 km NW–SE before being sinistrally offset by the Altyn Tagh fault and is found between the Qilian terrane and the North Qaidam basin. To the northeast of the Qilian terrane is the North China craton. The UHP belt formed through subduc-tion of oceanic litho-sphere, 560-495 Ma, and the resulting continental collision between the Qaidam and Qilian ter-ranes, 456-397 Ma (Gehrels et al, 2003; Mattinson et al, 2007; Song et al, 2003; Zhiqin et al, 2006); however, the number of subduction zones and the subduction directions are unkown. Several models have been proposed to explain the formation of the North Qaidam UHP belt, including 2 endmember models: one of which states that the Qilain Ocean subducted to the southwest under the combined Qaidam-Qilian

terranes (Gehrels et al., 2003; Mattinson et al, 2007), while the other states that the ocean was subducted to the north under the North China block (Zhiqin et al., 2006; Song et al, 2009ab).

Eclogites out-crop as blocks, boudins or layers throughout the North Qaidam metamor-phic belt. Because ec-logites are dry, they tend to record the peak pres-sures and temperatures that the region experi-enced as well as retro-grade pressures and temperatures. Recon-naissance analysis of the eclogites in this region record three dis-tinct stages of metamor-phism: pre-peak meta-morphism with pres-sures of 0.49-0.67 GPa at 410-490⁰C; peak eclogite facies metamor-phism at 2.7-3.4 GPa and 610-700⁰ C, and a retrograde stage from

PressurePressurePressurePressure----Temperature Estimates of Eclogites in the North Qaidam UltrahighTemperature Estimates of Eclogites in the North Qaidam UltrahighTemperature Estimates of Eclogites in the North Qaidam UltrahighTemperature Estimates of Eclogites in the North Qaidam Ultrahigh----Pressure Metamorphic Belt in ChinaPressure Metamorphic Belt in ChinaPressure Metamorphic Belt in ChinaPressure Metamorphic Belt in China

Chelsea Nissen


Few paleoclimate re-cords preserve high-resolution information for the middle Holocene in (near) coastal Portu-gal, but this region con-tains many caves within a few kilometers of the coast. In addition, shells of shallow marine invertebrates record sea surface conditions and some of these were harvested and pre-served in archaeological middens. We attempted to develop a paleocli-mate record from coe-val, middle Holocene limpets and a single stalagmite from coastal Portugal. The stalag-mite was collected ap-proximately 30 m from the 1 m2 entrance to the shallow but poorly venti-lated Glory Hole cave near the town of Nazare. U/Th dating demon-strated that the stalag-mite grew uninterrupted from 8.2-4.2 ka, and stable isotopic analysis revealed multiple epi-sodes of oxygen isotopic variability in excess of 5‰ in as little as 100 years, changes that are unlikely to reflect shifts in mean annual tem-

perature. Strong co-variance between sta-

lagmite δ13C and δ18O values argues for non-equilibrium crystalliza-tion, and thus we inter-pret these data as reflecting secondary controls on stalagmite isotopic ratios through kinetic effects and/or the evaporation and 18O-enrichment of cave dripwater. Comparison with the GISP2 Greenland ice oxy-gen isotopic time series reveals in-creases in North Atlantic air tempera-ture that were coin-cident with in-creases in evapoki-netic influences at Glory Hole, suggest-ing a possible cli-matic link between the two sites. Lim-pet shells were cracked and in some places de-graded, and despite careful preparation and delicate mi-crosampling, we were unable to ex-tract a stable iso-topic time series of sufficiently high

resolution to define seasonal shallow ma-rine temperature vari-ability. The back-ground, methodology, and results of this study will be presented to Iowa public and private elementary, middle, and high school students along with supporting educa-

tional materials.

Combined Stalagmite and LimpetCombined Stalagmite and LimpetCombined Stalagmite and LimpetCombined Stalagmite and Limpet----Based Holocene Paleloclimate Based Holocene Paleloclimate Based Holocene Paleloclimate Based Holocene Paleloclimate

Reconstructions from Coastal PortugalReconstructions from Coastal PortugalReconstructions from Coastal PortugalReconstructions from Coastal Portugal

Megan Denner

2009-2011

All geologic history is

full of the beginning

and the ends of spe-

cies–of their first and

last days; but it ex-

hibits no genealogies

of development.

Hugh Miller


Thin sections, prepared from sherds that were collected during recent excavations at site 13LN323, were ana-lyzed by point counting compositional elements, which included natural inclusions (sand and silt), non-natural inclu-sions (temper) and ma-trix (clay). Dominant temper lithologies are granite, gabbro and basalt. Temper was preferentially selected by different cultures, with earlier cultures

preferring granite, and later ones selecting gabbro and basalt. Clustering of temper, sand/silt and clay per-centages on trivariate plots indicates that pots were made from the same or similar material. The green color of hornblende observed in some thin sections indicates that firing temperatures of these pots did not ex-ceed 700oC Sediment samples were col-lected from nearby

A Quantitative Analysis of Ceramic Thin Sections at Site 13LN323, PalisadesA Quantitative Analysis of Ceramic Thin Sections at Site 13LN323, PalisadesA Quantitative Analysis of Ceramic Thin Sections at Site 13LN323, PalisadesA Quantitative Analysis of Ceramic Thin Sections at Site 13LN323, Palisades

----Dows State Preserve, Linn County, IowaDows State Preserve, Linn County, IowaDows State Preserve, Linn County, IowaDows State Preserve, Linn County, Iowa

Nicolas Slater

sources, and the per-centages of sand, silt and clay were calcu-lated and compared to those from the thin sections. Differences in composition indicate that none of the sedi-ment sources sampled was used for making these pots. Local availability of temper materials suggests that the inhabitants manufactured the pot-tery at or near the site. The source of the clay

remains unknown.

Recent studies from Borneo and Indonesia have increased our un-derstanding of the evo-lution of the Indonesian-Australian Summer Monsoon (InAuSM) sys-tem over the past 10,000 years (the Holo-cene epoch). However, little is known about the InAuSM in Australia or at centennial time-

scales. Here we pre-sent carbon and oxy-gen stable isotope data from two stalag-mites collected from cave KNI-51, located in the northern Kimberley region of tropical West-ern Australia, that pre-serve evidence of cen-tennial- and millennial-scale trends in the InAuSM during the

Monsoon Variability Preserved in Australian Stalagmites During the Early Monsoon Variability Preserved in Australian Stalagmites During the Early Monsoon Variability Preserved in Australian Stalagmites During the Early Monsoon Variability Preserved in Australian Stalagmites During the Early

HoloceneHoloceneHoloceneHolocene

Elizabeth Greaves

early Holocene. Mon-soon intensity and variability are attrib-uted to movement of the Intertropical Con-vergence Zone (ITCZ) and the El Nino-Southern Oscillation (ENSO); insolation ap-pears to have played a limited role on InAuSM variability during the

Holocene.

Our ability to understand multi-decadal to centennial-scale trends in tropical cyclone activity is limited by the short duration of, and limitations in, historical records. In order to extend these records for tropical Western Australia, we have analyzed mud layers in stalagmite KNI-51-11 from the Kimberley region of north-central Australia that

appear to be formed by cyclone-induced flood-ing. KNI-51-11 grew over the last 250 years and contains 39 mud layers. High uranium and low detrital Th abundances in this aragonite stalagmite allow extremely precise dating (±1 year over the past century) via U/Th mass spectrometry. Lin-ear interpolation between

Reconstructing Tropical Cyclone Frequency Using Mud Layers in Reconstructing Tropical Cyclone Frequency Using Mud Layers in Reconstructing Tropical Cyclone Frequency Using Mud Layers in Reconstructing Tropical Cyclone Frequency Using Mud Layers in

SpeleothemsSpeleothemsSpeleothemsSpeleothems

Nicholas Campbell

2009-2011

13 U/Th dates was used to establish an age model for the mud layers. When these mud layers are compared to historical storm records since 1906, the KNI-51-11 mud layers correlate 78% of the time with tropical cyclones that passed within 200 km of the

cave.

The North Qaidam Moun-tains on the northeastern edge of the Tibetan Plateau show evidence of ultrahigh-pressure (UHP) metamor-phism, indicating subduc-tion and exhumation of continental materials to > 90 km deep, within the mantle. The area most likely represents a suture zone, as an ophiolite is present, indicating the closing of an ocean. This ocean was located be-tween the North China and South China cratons about 514 million years ago, as dated from zircons in the ophiolite. The UHP meta-morphism occurred during the closing of the ocean ~495 million years ago. The North Qaidam Moun-tains were uplifted and the ultrahigh-pressure rocks were exhumed later, in the Cenozoic, by the India-Asia

collision and the resulting formation of the Himala-yas. This late tectonic event has effectively masked the older rock histories, so little is known about the early history of the North Qai-

dam area.

By understanding the pressure-temperature history of the eclogites included in the UHP ter-rane, we can reconstruct the formation of the NE Tibetan Plateau. Toward this purpose, I analyzed an eclogite under the petrographic microscope as well as with an elec-tron microprobe. The primary minerals included garnet, quartz and clino-pyroxene, with accessory minerals of rutile, titanite, amphibole and white

Using UltrahighUsing UltrahighUsing UltrahighUsing Ultrahigh----Pressure Eclogites to Reconstruct the Tectonic Pressure Eclogites to Reconstruct the Tectonic Pressure Eclogites to Reconstruct the Tectonic Pressure Eclogites to Reconstruct the Tectonic

Past of the North Qaidam Mountains, ChinaPast of the North Qaidam Mountains, ChinaPast of the North Qaidam Mountains, ChinaPast of the North Qaidam Mountains, China

Robin Drucker

mica. There are no reac-tion textures around the garnets, indicating a well preserved sample of (ultra)high-pressure condi-tions. The garnets are small, generally 1/2 mm or less in diameter, and euhedral with few inclu-sions. The white mica grains are well-formed flakes with no sign of retrogression. A titanite rim around the rutile does indicate that the rock experienced a change to lower pressure and tem-perature after peak pres-sure. These data corre-late well with reconnais-sance studies of eclogites from across the area; mineral zoning and pres-sure–temperature esti-mates will be collected to better constrain the tec-tonic history of the (U)HP

rocks.

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