Scientific Field Trips

Field-Trip Co-Chairs
Lon Abbott and Greg Hancock
GSA Contact
Beth Engle
Please contact trip leaders directly if you have questions about trip details. All trips begin and end at the Colorado Convention Center in Denver unless otherwise indicated. Trip fees include transportation during the trip; other services, such as meals and lodging, are noted with each trip by the following: B—breakfast, L—lunch, R—refreshments, D—dinner, ON—overnight lodging

Premeeting | Concurrent | Postmeeting | Associated Society Trips

Alert9/19/2013 - Due to the recent flooding in the Boulder, Colorado area, all field trip itineraries are under review.  If the trip area has too much damage and is inaccessible, the trip will be cancelled and current registrants will be notified by email.  This webpage will be updated as decisions are made.

10/9/13 - Trips 414 and 416 now have revised itineraries. Trips 408, 424, 426 have been canceled due to the flood.

Premeeting

Late-Breaking Field Trip!
428. Effects of the 2013 Front Range flood on low-order streams and alluvial terraces near Boulder, Colorado, USA
Leaders: Lon Abbott, University of Colorado; Mariela Perignon, Lisa Dierauf, Dave Sutherland
Sat., 26 Oct. US$45 (L). Check-in time is 8:30 a.m.; returns to Colorado Convention Center by 4 p.m. Also see: Late-Breaking Session on the flood.
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The September 2013 Front Range flood was a historic event with significant and tragic consequences for thousands of people across Colorado. Sustained heavy precipitation and resulting torrential flows led to widespread geomorphic change throughout the region. Although road damage makes most of the mountainous terrain affected by the flood inaccessible, much can be observed at the interface between the Great Plains and the Rocky Mountain foothills in and around Boulder County. We will use the city's extensive open space trail system, much of which was significantly damaged but is gradually being restored, to explore the response of low-order streams to this event and consider the role of large floods in the evolution of Front Range topography. Both debris flows and localized extreme incision and aggradation are evident in these drainages. We will compare the signature of this single, rare event on these low-order channels with the characteristics of the Pleistocene alluvial terraces that flank them. We will also examine the behavior of Bear Creek, a higher-order stream, as it transitions from a narrow bedrock channel in the foothills to a heavily populated alluvial fan on the Great Plains. Although we are not able to provide a definitive summary of the 2013 flood and its scientific lessons, we aim to facilitate interesting observations that will trigger animated dialog among trip participants. We hope that this will ultimately lead to new inquiry on the geomorphic effects of extreme floods and the role that such events play in the long-term evolution of landscapes.

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Primary leader e-mail: lon.abbott@colorado.edu
Lon Abbott is on the University of Colorado geology faculty. His research focus is landscape evolution of mountains and plateaus. He has also authored three books and 14 geology articles aimed at a popular audience.

Primary Leader Experience
Abbott studies landscape evolution and river incision along the Colorado Front Range and in Grand Canyon. His most recent published book, Geology Underfoot along Colorado's Front Range, examines the 1976 Big Thompson flood, one of Colorado’s previous devastating flood events. Abbott grew up in Boulder and knows the field trip stops especially well. Some stops lay within areas his field geology students map each year and others are near his house. He watched Bear Creek rise throughout the flood event, so he can provide an anecdotal time series of what transpired.

402. Early Mesozoic Sandstones in Utah’s Canyon Country: Signatures of Subsurface Microbes, Reducing Fluids, and Jurassic Earthquakes.
Wed.–Sat., 23–26 Oct. US$445 (L, R, 3ON). Trip starts in Grand Junction, Colorado, and makes a counter-clockwise circuit that ends in Denver via Green River, Kanab, Monument Valley, Moab, and Grand Junction.
Leaders: David B. Loope, University of Nebraska–Lincoln; Richard M. Kettler, Peter S. Mozley, Derek T. Burgess
Cosponsor: Society for Sedimentary Geology
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Emphasis will be on (1) microbially mediated, iron-oxide cements and concretions, and their relevance to the understanding of subsurface pathways for CO2, O2, and methane, and to the search for extraterrestrial life (Navajo Sandstone in Grand Staircase–Escalante National Monument, and Shinarump sandstone near Colorado City, Arizona); (2) pathways of fluid flow across reservoir seals (Navajo, Carmel, and Entrada formations east of Capitol Reef National Park); and (3) sand volcanoes buried in Navajo crossbeds as recorders of Jurassic earthquake sequences (Navajo at Zion National Park).

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Primary leader e-mail: dloope1@unl.edu
After working as a seasonal ranger at Canyonlands National Park and getting hooked on wind-deposited sandstones of the Colorado Plateau, David Loope did graduate work at the University of Wyoming. A professor at University of Nebraska since 1981, he teaches Geology 101, as well as courses in sedimentology and stratigraphy. With Nebraska colleagues, Loope has carried out extensive, NSF-funded field studies of the geologic history and paleoecology of the Nebraska Sand Hills. In the late 1990s he worked with paleontologists from the American Museum of Natural History and the Natural History Museum of Los Angeles County on Cretaceous, dinosaur-bearing sandstones in Mongolia and Argentina. Since 2009, he has been returning to southern Utah to study, with geochemist Richard Kettler and geomicrobiologist Karrie Weber, the late-stage diagenesis of the Jurassic Navajo Sandstone. This work has been published in Geology, Sedimentology, and the Journal of Geology.

Primary Leader Experience
Loope, a GSA Fellow since 1990, has led GSA field trips to the Nebraska Sand Hills (1993, 1995) and to the southern Utah portion of the Colorado Plateau (2004). He has taught University of Nebraska field camps multiple times at both Eureka, Nevada, and Shell, Wyoming. Immediately after college, he worked for four seasons as an interpreter for the National Park Service, based in Moab, Utah.

403. Making the Case for the Picuris Orogeny: Evidence for a 1.5 to 1.4 Ga Orogenic Event in the Southwestern United States.
Wed.–Sat., 23–26 Oct. US$436 — Canceled.  

404. The Laramie Anorthosite Complex and Its Contact Relationships.
Wed.–Sat., 23–26 Oct. US$373 (B, L, R, 3ON).
Leaders:  B. Ronald Frost, University of Wyoming; James S. Scoates, Robert L. Bauer
Cosponsor: GSA Mineralogy, Geochemistry, Petrology and Volcanology Division
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The Laramie Anorthosite Complex (LAC) is the one of the best-studied and most accessible anorthosite complexes in the world. Its components, which range in age from ca. 1432 to 1436 Ma, are exposed over an ~800 km2 area in the southern Laramie range of southeastern Wyoming. Although the eastern margin of the LAC has been truncated by Laramide faulting, its western margin includes local areas of contact with adjacent Archean gneiss and supracrustal rocks that were locally reworked by Paleoproterozoic deformation. Three major compositional units of the LAC are recognized: (1) anorthositic rocks, (2) leucogabbroic rocks, and (3) monzonitic rocks. This trip will examine examples of each of the major LAC units and contact metamorphic relationships between these major components and adjacent Archean amphibolitic to pelitic country rocks. The major LAC components and their variants are well exposed in road cuts on Wyoming Hwy 34, which provide a field basis for discussing the intrusive and crystallization history of the LAC and its local contact metamorphic effects. Structural and contact metamorphic relationships between the monzonitic units of the LAC and adjacent country rocks are well exposed on ranch properties along the northwestern margin of the LAC.

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Primary leader e-mail: rfrost@uwyo.edu

Ron Frost is Professor of Geology at the University Wyoming, where he has served on the faculty since 1979. He received his B.A. from the University of Virginia in 1969, and his M.S. (1971) and Ph.D. (1973) from the University of Washington. After teaching briefly at the University of Minnesota-Duluth and Michigan Technological University, he began his current position at the University of Wyoming.

Primary Leader Experience
Frost’s research has concentrated in several fields in petrology, including the geologic evolution of the Wyoming Archean Province, seafloor metamorphism and the formation and metamorphism of serpentinites, metamorphism and melting of sulfide ore deposits, the origin and classification of granites, the stability of Fe-Ti oxides in igneous rocks, and the formation and evolution of Proterozoic anorthosites and related rocks. His work on the Laramie Anorthosite Complex (LAC) began in 1988 with work on the granitic components of the LAC and continues to the present. Many of his studies have been in collaboration with Don Lindsley and James Scoates.

405. Colorado Geology Then and Now, 1901 to 2013: Following the Route of the Societies’ 1901 Trip through Central Colorado—Evolution of Geological Thought and Discovery.
Thurs.–Sat., 24–26 Oct. US$340 (B, L, D, R, 2ON).
Leader: Elizabeth Simmons, Colorado Scientific Society and Metropolitan State College of Denver
Cosponsors: Colorado Scientific Society, Western Interior Paleontological Society, GSA History and Philosophy of Geology Division, GSA Mineralogy, Geochemistry, Petrology and Volcanology Division.
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Join us as we re-trace a part of the route of the 1901 field trip through Colorado that was sponsored by CSS/GSA/AAAS as part of that year’s summer meeting. The historic trip was led and attended by prominent geologists of the time, including several CSS and GSA founders, presidents, officers, and members, such as S.F. Emmons, Arthur Lakes, T.C. Chamberlin, Whitman Cross, and C.R. VanHise. Their ten-day journey covered a large part of Colorado by train, horseback, and foot. Geologic and physiographic features of Precambrian through Pleistocene terranes were examined and mines visited. On our trip we will visit stops made on the 1901 excursion at several central Colorado locations. Experts on Colorado geology will discuss the historic and geologic significance of these areas, subsequent modern interpretations, and related development of geologic concepts. Along the route, we will pass through the heart of the Colorado Rocky Mountains, investigate the fascinating geology, and examine the complex stratigraphy, paleontology, tectonics, petrology, and geothermal features of Proterozoic to Pleistocene sequences. Planned stops include a Canon City dinosaur quarry, an Ordovician fish locality, Royal Gorge, northern Rio Grande Rift, Brown’s Canyon fluorite district, Hecla Junction welded tuff, Sawatch Uplift, Ruby Mountain, glacial geomorphology, historic Leadville and Aspen mining districts, Snowmass Mastodon Exhibit, Cambro-Ordovician sequences in Glenwood Canyon, the Dotsero maar and flows (Colorado’s youngest volcano), Eagle Basin, Loveland Pass, and a mine tour in the historic Idaho Springs District. Overnight in historic Salida and in Glenwood Springs—hot springs pool optional!

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Primary leader e-mail: cloverknoll@comcast.net
Beth Simmons has a Ph.D. in Colorado history and teaches the geology of Colorado at Metropolitan State University in Denver. In addition to numerous scientific and historical articles, her published books include The Legacy of Arthur Lakes, The Rooney Ranch, A Quick History of Idaho Springs, and a fun children’s guide book to Dinosaur Ridge, Darin and Denise Discover Denver’s Dinosaurs. Recently, as the director and script writer, she and a large group of volunteers from Friends of Dinosaur Ridge completed a much-acclaimed hour-long documentary about the discovery of the dinosaur bones in Golden and Morrison in the 1870s. Beth serves as historian for the Colorado Scientific Society.

Primary Leader Experience
Beth Simmons has twenty years of experience leading field trips for local geology and history classes, plus is one of the founding members of the Florissant Scientific Society, a local study group with fabulous field trips. She has also led historic day trips for the Rocky Mountain Association of Geologists and Colorado Scientific Society.

406. Origin and Evolution of the Upper Colorado River System: Evaluating the Competing Roles of Neogene Tectonism and Drainage Integration.
Thurs.–Sat., 24–26 Oct. US$343 (B, L, R, 2ON).
Leaders: Andres Aslan, Colorado Mesa University; Karl E. Karlstrom, Eric Kirby
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The evolution of the Colorado River plays a critical role in our understanding of late Cenozoic landscape evolution across the western U.S. This trip focuses on the Upper Colorado River basin and evaluates the hypotheses that (1) the upper Colorado River developed prior to integration of the lower Colorado River through Grand Canyon, and (2) differential uplift of the Colorado Rockies has driven river incision along the upper Colorado Basin during the Neogene. In the context of key outcrops and new data, we will discuss (1) river incision histories of the Colorado, Gunnison, and Yampa Rivers; (2) the timing of the transition from late Cenozoic intermontane basin-filling to widespread exhumation; (3) the role of stream piracy during Colorado River integration; (4) effects of isostatic response to denudation; and (5) the potential effects of Neogene changes in mantle flow and/or buoyancy on the elevation history of the Colorado Rockies.

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Primary leader e-mail: aaslan@coloradomesa.edu
Professor of geology at Colorado Mesa University since 1999; Ph.D. in geology from CU-Boulder in 1994; B.S. in geology from Brown University in 1986. Areas of specialization: fluvial geomorphology and sedimentology, soils, and landscape evolution

Primary Leader Experience
Dr. Andres Aslan is a professor of geomorphology at Colorado Mesa University. His research expertise is in fluvial geomorphology and sedimentology, and his current research activities are focused on long-term river histories in the Rocky Mountain region. He worked for the Bureau of Economic Geology at UT-Austin and taught at Oberlin College prior to teaching at Mesa. This field trip highlights ongoing NSF-funded research evaluating the Neogene uplift and river incision history of the upper Colorado River Basin. He served as the primary leader of prior GSA field trips in 2010 (national meeting), 2008 (national meeting), and 2005 (regional meeting). All of the prior trips were well attended and successful. This trip is an update of the ongoing research presented on his 2010 GSA field trip.

407. Sevier Fold-Thrust Belt to Laramide Foreland Transect: Exploring the Evolution of a Complex Orogenic System.
Thurs.–Sat., 24–26 Oct. US$368 (1D, R, 2ON). This trip begins in Salt Lake City, Utah, and ends in Denver, Colorado.
Leaders: Adolph Yonkee, Weber State University; Arlo Brandon Weil, Gautam Mitra
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The Sevier fold-thrust belt and Laramide foreland comprise two interrelated mountain systems that formed during subduction-related orogenesis. This field trip will explore differing structural styles between these two classic belts and how integrated structural and paleomagnetic studies are being used to better understand regional deformation fields and their relations to plate dynamics. The trip begins in Salt Lake City, Utah, heading northward to Jackson Hole, Wyoming, along curved thrust systems of the Sevier belt. Here we will view and discuss internal strain patterns in limestones and redbeds, paleomagnetically determined vertical-axis rotations, regional thrusting relations, and synorogenic sedimentation in foreland basins, focusing on processes and feedbacks that lead to systematic curvature in mountain belts. The trip then heads westward across the Wyoming foreland, with stops along the Wind River Mountains, Sweetwater Arch, and Laramie Range. Here we will view deformation styles of large-scale basement-cored arches and associated cover folds, as well as paleostress/strain patterns recorded by minor fault arrays and anisotropy of magnetic susceptibility (AMS) fabrics in redbeds, focusing on similarities and differences in tectonic evolution between the Laramide and Sevier belts and on relations to flat-slab subduction. The trip will include short walks to observe structural relations in key outcrops. Please join us as we explore two intriguing mountain belts, enjoy outstanding scenery, and have lively discussions on recent advances in our understanding of curved mountain systems and foreland deformation.

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Primary leader e-mail: ayonkee@weber.edu
Adolph Yonkee is professor in the geosciences department at Weber State University. His fields of study include structural geology, geochemistry, and tectonics. Current research interests include evolution of curved mountain systems, relations of foreland deformation to plate dynamics, thermochronology and slip histories of thrust systems, relations between fluid-rock interaction and deformation in fault and shear zones, Neoproterozoic to Cambrian rift history and evolution of the western Cordillera margin, and analysis of fracture networks with applications to bedrock aquifers.

Primary Leader Experience
Adolph Yonkee has recently co-authored articles on regional patterns of layer-parallel shortening and paleostress across the Laramide foreland, development of curved thrust systems and strain patterns in the Wyoming salient, and integrated microstructural and geochemical characteristics of deformed conglomerates that record strain softening processes. Adolph has previously led multiple field trips for past GSA regional and national meetings, the Utah Geological Association, and most recently the Association of Environmental & Engineering Geologists.

408. There’s More to This Than Meets the Eye: Human-Induced Changes in Hydrology, Geomorphology, and Biogeochemistry in High-Elevation Watersheds of the Southern Rockies.
Fri., 25 Oct. US$105 (L, R). — Canceled due to flood.
 

409. Laramide Basin CSI: Comprehensive Stratigraphic Investigations of Paleogene Sediments in the Colorado Headwaters Basin, North-Central Colorado.
Fri.–Sat., 25–26 Oct. US$212 (L, R, 1ON).
Leaders: James C. Cole, USGS; Marieke Dechesne, James H. Trexler, Patricia H. Cashman
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This field trip will explore the geologic record within the Colorado Headwaters Basin (CHB; North Park and Middle Park areas of north-central Colorado) and reconstruct the depositional record of the Paleogene Coalmont and Middle Park Formations. Recent multidisciplinary research shows a considerably more complex history of Laramide foreland-basin sedimentation and episodic deformation than previously recognized. Stops will showcase stratigraphic sections that record significant variations in depositional environments (fluvial, deltaic, lacustrine, and paludal/coal mires). These variations reflect competing influences of sediment supply, basin-margin uplifts, internal basin deformation, accommodation space, and climate. Paleocurrent trends and distinctive volcanic-porphyry cobbles indicate significant sediment transport northward from central Colorado sources (unexpected implications for paleodrainage). Rapid subsidence is indicated by great sediment thickness (>2.5 km) and persistent expanses of lacustrine ponding, and yet absence of evaporates and scarcity of paleosols suggest sedimentation kept pace and some external drainage was maintained. Internal unconformities in the Coalmont and Middle Park Formations probably reflect shifting of the basin center(s) in response to episodic local uplift/subsidence. Stops will also present evidence for (1) widespread uplift and erosion (>1.4 km) in early Paleocene time; (2) broad tilting and local asymmetric folding before onset of subsidence/deposition in middle Paleocene time; (3) faulting and local intra-basin uplift during sedimentation; and (4) post-middle(?) Eocene folding and uplift of basement blocks along reverse faults. The present shape of the CHB reflects the geometry of (largely) post-depositional faults and folds that are (in many cases) different from the structures of the original depositional basin.

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Primary leader e-mail: jimcole@usgs.gov
Dr. Jim Cole is a research geologist with the U.S. Geological Survey in Denver.

Primary Leader Experience
Jim Cole’s investigations have ranged widely through Colorado, Saudi Arabia, southern Nevada, Albuquerque rift basins, and back to Colorado. His recent studies have covered Precambrian petrology and structure, Laramide structure, and evolution of drainage and landscape in northern Colorado. He is the Project Chief for the USGS Colorado Headwaters Basin Project for the National Cooperative Geologic Mapping Program (http://gec.cr.usgs.gov/projects/northpark/).

410. Coal Geology and Mining History of the Raton Mesa Coal Region.
Fri.–Sat., 25–26 Oct. US$220 (L, R, 1ON).
Leaders: Chris Carroll, Wyoming State Geological Survey; Gretchen Hoffman
Cosponsor: GSA Coal Geology Division
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The Tertiary and Cretaceous coal resources of the Trinidad, Colorado, area have a long history of coal production, labor struggles, and specialty coals. The metallurgical properties of the Raton Mesa Coal Region are an invaluable commodity as important today as they were in 1890. This field trip will visit many of the significant historical sites in the area, including the Ludlow Massacre of 1914 and the old mining towns of Berwind, Cokedale, and Boncarbo. We will visit an exposure of the K-T boundary within the Raton Formation coals and see how mining and coalbed methane activity coexist today near Weston.

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Primary leader e-mail: Chris.Carroll@wyo.gov
Chris Carroll has been the coal geologist for both the Wyoming and Colorado Geological Surveys for over 15 years. He has studied all of the Cretaceous and Tertiary coal basins in those states and is an expert on the coal resources, coal quality, and coal economics of Western U.S. coal. Chris is a past chair of the GSA Coal Division. He has written more than 20 publications for the Colorado Geological Survey.

Primary Leader Experience
Mr. Carroll has led several geologic field trips for GSA, Women in Mining, AAPG, and WIPS. He has also organized several private multi-day whitewater rafting excursions in the Western U.S. He last led a GSA field trip in 2010 to Dinosaur Ridge and in 2004 to the Somerset coal field with the Coal Geology Division.

411. Geological Photography: Capturing and Processing Geologic Images with Digital Camera and Gigapan.
Fri.–Sat., 25–26 Oct. US$162 (1B, 1L, R).
Leaders: Ellen M. Bishop, Whitman College; Marli Bryant Miller, Stephen G. Weaver, Mike Franz
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This trip focuses on fine-tuning digital photographic skills and capturing compelling, professional-quality geologic images. It will engage both traditional digital photography and Gigapan imaging as we explore the diverse geology of Roxborough State Park, south of Denver. On the first day, participants will practice fine-tuning their photographic techniques, guided by three outstanding geological photographers: Ellen Morris Bishop, Whitman College; Marli Bryant Miller, University of Oregon; and Steve Weaver, Colorado College. In addition, participants will shoot Gigapan images, guided by Gigapan expert Mike Franz, using Gigapan Epic equipment. The field day includes applying professional techniques to capture better geologic images; practicing multiple scales of imaging, from panoramic landscapes to macro; and understanding how to adjust camera settings to optimize your images. We will work in small groups. Each group will work with Gigapan as well as “traditional” digital photography. On Day 2, we will reconvene to share images and learn simple techniques to optimize images shot at Roxborough, as well as viewing and uploading Gigapan work. The resulting, fine-tuned images will be included in the digital display at the GSA photo exhibition; Gigapan images will be uploaded for display on the Gigapan website and on a Gigapan monitor at the GSA photo exhibition. Equipment required: Digital camera (preferred: camera that allows control of aperture and shutter speed and shoots RAW files); laptop for Gigapan uploads; and tripod. If you do not have a tripod, please contact Ellen Bishop to arrange loan of appropriate equipment.

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Primary leader e-mail: paleobishop@gmail.com
Ellen Bishop served is a visiting professor of geology and environmental studies at Whitman College. She earned a Ph.D. in geology at Oregon State University in 1983, specializing in petrology and tectonics. Her research includes geology of accreted terranes, Pacific Northwest and Karakorum Himalaya; Arkansas alkalic province; and Early Tertiary volcanism, Pacific Northwest. Lifelong passion: connecting people with landscape and climatic history through the arts and creative expression of landscapes.

Primary Leader Experience
Ellen Bishop is an academic and research geologist with 30 years of experience in engaging the arts to communicate science. Her photography includes use of large and medium format cameras, and her current digital arsenal includes iPhone, Canon p/s, and Nikon D4, D800. Bishop teaches course in environmental and geological photography at Whitman, and field courses in geophotography. She established, and now is principal organizer of, the GSA Annual Photo contest/exhibition. Learn more at www.ellenmorrisbishop.com.

412. Gully Erosion along the West Bijou Escarpment, Colorado High Plains.
Sat., 26 Oct. US$87 (L, R).
Leaders: Greg Tucker, University of Colorado; Francis K. Rengers
Cosponsor: GSA Quaternary Geology and Geomorphology Division
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This trip explores gully erosion on the high plains of Colorado. Gullies on the semi-arid high plains form a critical link between uplands and intermittent alluvial rivers, and they have been shown to persist for thousands of years. In addition to their importance in shaping landscapes, gullies can also be destructive natural hazards. This field trip will provide an advanced guide to gully erosion processes and dynamics. During this field trip, we will explore a study site that functions as a natural experiment for monitoring gully dynamics. The site lies along a prominent east-facing escarpment in the West Bijou Creek valley. The escarpment is dissected by networks of gullies that exhibit multiple, prominent headscarps ranging from a few tens of centimeters to up to three meters in height. Repeated terrestrial LiDAR scans and historic aerial photography reveal rates of headscarp motion on the order of decimeters to more than a meter per year. We will focus on the role of headcuts in gullies as analogues for waterfalls in more resistant rock. In situ hydrologic monitoring, time-lapse photography, and repeat terrestrial LiDAR provides insights into the governing hydrologic and geomorphic processes responsible for gully dynamics. We will share insights from six years of field monitoring, comparing this short-term data set with observations from historical photos that reach back to the late 1930s. We will also explore the dynamic relationship between vegetation and gully morphology.

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Primary leader e-mail: gtucker@colorado.edu
Greg Tucker is a Fellow of the Cooperative Institute for Research in Environmental Sciences (CIRES) and an associate professor in the Department of Geological Sciences at the University of Colorado at Boulder.

Primary Leader Experience
Tucker has been fascinated by gully erosion since his first field trip to the Colorado High Plains in 1999. He began building a monitoring network at the field site when he moved to Colorado in 2004, and has been steadily fleshing it out since then.

413. Geology along the Rocky Mountain Front Range, Morrison to Golden, Including Structure, Stratigraphy, Paleontology, Volcanology, and Economic Geology (Pre-Meeting).
Sat., 26 Oct. US$107 (L, R).
Leaders: Timothy B. Connors, National Park Service; Norb Cygan
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The geologic strata exposed along the Laramide uplift of this section of the Front Range are exceptionally good examples of late Paleozoic through early Cenozoic history that includes the Denver Basin, overlying Tertiary lava flows, and with few gaps, continuous sediment deposition of Mesozoic rocks. Precambrian rocks are well exposed in this area, with a 1.4 billion year hiatus between the Archean and the Pennsylvanian rocks. Laramide faulting along the Front Range is also important to the geologic story. This field trip will explore the rock exposures of these formations in Golden and Morrison, Colorado. The visitor will come away with an idea of just how the Rockies were formed and discover why we call the Dinosaur Ridge trackways the Dinosaur Freeway. We will also observe economic geology in the area, which includes oil and gas, uranium, and coal and clay mining.

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Primary leader e-mail: tim_connors@nps.gov
Tim Connors obtained geology degrees from the University of Toledo (B.S. 1991 and M.S. 1996) and has been a geologist with the National Park Service Geologic Resources Division, Denver, since 1998. He has spent the last 15 years creating GIS-based geologic maps for National Park Service areas in the lower 48 states, Hawaii, Alaska, and the Virgin Islands. From this experience, he is well versed in the geology of the U.S. and numerous geologic terranes, features, and processes. He also teaches geology at the University of Colorado in Denver. Teaching duties have included physical and historical geology, the geology of Colorado, and teaching courses to science and math teachers as part of the Rocky Mountain Middle School Math and Science Partnership. Tim has also proudly served on the Board of Directors for the Friends of Dinosaur Ridge (Morrison, Colorado) since 1999, and has had a keen interest in the expansion and establishment of the Morrison-Golden Fossil Areas National Natural Landmark (that encompasses Dinosaur Ridge and Fossil Trace Golf Course areas). Tim is mainly a stratigrapher and sedimentary geologist and also enjoys the aspects of data management and presentation as it pertains to distributing geoscience information.

Primary Leader Experience
Tim has proposed, organized, and conducted field trips for academics, lay persons, societies, professional geologists and engineers, and school children since the 1990s. He has vast experience in U.S. geology from visits and trips to more than 100 National Park areas. He has also led trips in Ohio, Colorado, Wyoming, South Dakota, Utah, New Mexico, and Arizona. Most of the trips concerned stratigraphy, sedimentology, paleontology, and paleoenvironment interpretation. He has led and/or participated in several GSA-sponsored field trips for the Friends of Dinosaur Ridge in 1999, 2002, 2007, and 2010 related to Dinosaur Ridge. He has led numerous university groups on various field trips to showcase Colorado and Colorado Plateau geology, Black Hills (South Dakota–Wyoming), Big Horn Basin (Wyoming), and Yellowstone National Park area over the years. He has extensive experience in preparing field trip guides, budgets, lodging arrangements and trip logistics, as well as serving as a driver on several excursions (with 15-passenger van certification from the University of Colorado) with a flawless driving record.

414. Rocky Mountain Unsaturated Zones—Exploring Fire-Earth-Sky Connections.
**Flooding, gullying, and sediment deposition have impacted all sites on this trip; however, we expect to regain access to key sites or suitable analogs by 26 October. An additional topic of discussion during the field trip will be the role of antecedent conditions on runoff generation. Safety and enjoyment will be our top priorities; however, it should be noted that additional walking over uneven terrain will likely be required and that several sites may not be wheelchair accessible.**
Sat., 26 Oct. US$68.
Leaders: David A. Stonestrom, USGS; Brian Ebel, Bruce D. Honeyman, Dean E. Anderson, Suzanne Prestrud Anderson, Geoffrey N. Delin
Cosponsors: Unsaturated Zone Interest Group; GSA Hydrogeology Division; International Association of Hydrogeologists
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This multi-segment field trip, led by subject-matter experts, will highlight four different multidisciplinary research efforts aimed at crucial problems involving unsaturated zones in the Rocky Mountain area. The first segment will investigate linkages of large hot fires to short- to long-term changes in the partitioning of rainfall and snowmelt into infiltration and runoff, with attendant flood generation and sediment transport. These linkages will be examined within the context of enhanced potential for extreme flooding and debris flows caused by hyperarid conditions following the September 2010 Four Mile Canyon fire—at the time the most costly in Colorado history. The second segment will investigate a site in the Boulder Creek member of the NSF-sponsored Critical Zone Observatory (CZO) network, where data-driven studies are exploring interactions among water, soil, and boundary-layer ecosystems across landscapes that include little-explored thick unsaturated zones on deeply sculpted erosional terrain. The third segment will investigate seasonal systematics of elemental exchanges across the land-atmosphere interface along transitions from undisturbed to urbanized land (comprising one investigational axis) and from prairie grassland to montane forests (comprising another). This portion will include a visit to an instrumented short-grass prairie site at the Rocky Flat National Wildlife Refuge, where land surface fluxes of CO2, CH4, N2O, and water vapor are being correlated to soil-carbon dynamics. The final segment will investigate the legacy of nuclear weapons production, environmental contamination, and remediation at the Rocky Flats industrial site. The field trip will end with an optional dinner in an informal setting.

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Primary leader e-mail: dastones@usgs.gov
Dave Stonestrom is a research hydrologist with the U.S. Geological Survey in Menlo Park, California. He works on problems involving unsaturated zones in settings ranging from tropical rainforests to hyperarid deserts to coastal chronosequences. He is currently lead scientist for integrated unsaturated zone studies; a national hydrology research advisor; and co-coordinator for the USGS Toxic Substances Hydrology Program’s Amargosa Desert Research Site.

Primary Leader Experience
Dave has helped develop and teach courses in unsaturated-zone hydrology, isotopic and heat-tracing techniques, and surface water–groundwater interactions. He has served on advisory committees concerned with cleaning up the nation’s weapons production facilities and has published on topics of pedogenesis, contaminant transport, and groundwater recharge.

415. Discovering Treasures for Educators: Behind the Scenes in Earth Sciences at the Denver Museum of Nature & Science.
Sat., 26 Oct. US$64 (R).
Leaders: Samantha Richards, Denver Museum of Nature and Science; Carol Lucking, Ian Miller
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The Denver Museum of Nature & Science is the Rocky Mountain region’s leading resource for natural history collections and informal science education, all of which help us study and experience the natural wonders of Colorado, Earth, and the universe. The museum’s earth science collections include geology, vertebrate and invertebrate paleontology, and paleobotany. The gem and mineral collection focuses on Colorado and includes a number of regional iconic specimens. The micromount mineral collection is the second largest in the nation and contains specimens from around the world. The rock collection includes historical and building stones. The meteorite collection has samples from around the world, with a significant fraction from Colorado. The vertebrate paleontology collection consists mainly of Cenozoic mammals, Jurassic and Cretaceous dinosaurs, Cretaceous seaway fish and reptiles, and a number of complete skeletons. The paleobotany collection consists mainly of Cretaceous–Eocene leaves and is the second largest collection of its kind in the nation. The invertebrate paleontology collection’s main strengths are Cambrian-Ordovician trilobites, Cretaceous seaway mollusks, and Eocene insects. The museum also has a state-of-the-art fossil preparation laboratory where more than 100 volunteers prepare fossils for display and research. This trip will take you behind the scenes to view these spectacular collections and learn from museum scientists about past, current, and future research happening at the museum. Learn how to use the museum as a resource and how to teach with objects in your classroom. Plus: take a sneak peek into our new Education and Collections Facility, which officially opens in 2014.

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Primary leader e-mail: samantha.richards@dmns.org
Samantha Richards is the Educator/Coordinator for Earth Gallery Programs at the Denver Museum of Nature & Science. Samantha joined the Museum in 2010 after serving as the Volunteer Coordinator at the Molly Brown House Museum. From 2006–2009, she was the Director of Public Programs at the Paleontological Research Institution and its Museum of the Earth. She is the educator for Prehistoric Journey, the award winning exhibition that takes visitors on a 3.5 million year fossil journey through Earth’s history. She also served as the educator for temporary exhibitions including “T. rex Encounter,” “A Day in Pompeii,” and “Mammoths and Mastodons: Titans of the Ice Age.” Samantha participated as the lead educator in the Snowmastodon Project™. In the fall of 2010, Samantha saw 8,500 school students in just one week in the Roaring Fork Valley and was also responsible for planning and implementing the large public events in both Snowmass Village and at DMNS in 2010 and 2011.

Primary Leader Experience
Samantha earned her master’s in museum studies from the University of Colorado at Boulder in 2006 and her bachelor’s in environmental geology from the University of Michigan in 2004. She has led many tours of earth science exhibits in several museums as well as outdoor geology trips and fossil collecting field trips throughout upstate New York and Pennsylvania. Her expertise in object-based and inquiry-based education in earth sciences will be utilized during this field trip.

416. Lessons Learned from the 1982 Lawn Lake Dam Failure Flood and the 1976 Big Thompson Canyon Flood, Colorado.
**The itinerary for the originally scheduled trip is inaccessible due to the flooding. A new itinerary has been organized as follows.**
Revised Title:
Communicating Environmental Hazards, Impacts, and Mitigation from Floods in the Waldo Canyon Fire near Colorado Springs, Colorado
Sat., 26 Oct. US$95 (L, R).
Leaders: Robert D. Jarrett, U.S. Geological Survey, National Research Program; Melissa Wygant, William Hoyt
Cosponsor: U.S. Geological Survey, University of Northern Colorado (Collaborative trip with American Institute of Professional Geologists)
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NEW DESCRIPTION
This field trip will head to the Garden of the Gods, Center, Colorado Springs. The objectives of the fieldtrip are primarily to visit a variety of evidences of natural hazards in the Colorado Front Range including wildfires, floods, rock falls, landslides, debris flows, and other hazards. A primary/critical focus is to exchange ideas on improving communications to reduce the risk of these hazards, disaster mitigation, and socioeconomic impacts. We will discuss the general geological and hydrological setting of the Colorado Front Range, environmental setting, natural hazards and risk including geologic, hydrometeorologic, wildfire, floods (including Late-Pleistocene floods), geomorphologic, and the effects of Holocene climate variability on maximum flooding.

There also will be a brief overview of the 1976 Big Thompson Canyon and the 1982 Lawn Lake (dam failure) floods (originally planned GSA fieldtrip).
Original Trip Description:
The main focus of the fieldtrip is to generate discussion of the hydrometeorology, flood, and paleoflood hydrology, river hydraulics, geomorphic change, and dam-break analysis in mountain-river systems. Another important focus is on research on lessons learned to help improve flood warning and reduce loss of life during flash flooding. On 15 July 1982, the Lawn Lake Dam failed in the early morning hours, cut a 5-mile-long erosion scar down the Roaring River in Rocky Mountain National Park, deposited a 42-acre boulder field at its confluence with Fall River, failed Cascade Lake Dam, and caused exceptional flooding along the Fall River and Big Thompson River in the community of Estes Park. The flood was contained within Lake Estes formed by Olympus Dam. Damages totaled $31 million and three people lost their lives. Also, on 31 July 1976, the Big Thompson Canyon flooded due to an extraordinarily intense thunderstorm located downstream from Estes Park to about 10 miles to the east near Drake. The flood swept through the canyon, killing 145 people and causing US$35 million in damages. The 1976 flood emphasized the poor understanding of flood hydrology in Colorado and resulted in extensive multidisciplinary flood research. The first stop of the field trip will be at the headwaters of the Big Thompson River Basin, following the trace of the 1982 then 1976 floods, and will proceed downstream in Big Thompson Canyon to Loveland.

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Primary leader e-mail: paleoflood@comcast.net
Robert Jarrett earned a B.S. degree in hydrology from the University of New Hampshire in 1971, and M.S. (1979) and Ph.D. degrees (1987) in civil engineering (water resources) from Colorado State University. From 1971 to 1974, Jarrett primarily worked on flood hydrometeorology and hydraulic analyses of the 1972 Agnes Flood with the U.S Army Corps of Engineers in Buffalo, New York. From 1974 to 2012, he worked for the U.S. Geological Survey in Lakewood, Colorado. Jarrett was the Chief of the USGS’s National Research Program project “Paleohydrology and Climate Change.”

Primary Leader Experience
Jarrett’s overall research focus is on conducting interdisciplinary research that addresses critical water issues facing the U.S., particularly to develop cost-effective and reliable new methods to help quantify the magnitude and frequency of floods and help reduce loss of life and economic loss from hydrologic hazard such as floods, dam-failure floods, debris flows, and wildland fire floods and evaluating the effects of climatic variability on these processes. Jarrett has over 40 years of experience in flood hydrology and hydraulics and fluvial geomorphology, with much of his career working on integrating paleoflood hydrology in flood-hazard mitigation, dam safety, and other water-resources issues. Since retirement, Jarrett has done consulting work relating to applications of paleoflood hydrology. He is also a scientist emeritus with the USGS.

417. The Role of Bioturbation in Producing the Mima-Type, Mima-Like, and Various Related Mounds and Heaps in the Greater Denver-Boulder Area, Colorado.
Sat., 26 Oct. US$91. — Canceled.
 

top CONCURRENT WITH THE MEETING

418. Ancient Denvers: A Journey through the Front Range’s Geologic History.
Sun., 27 Oct. US$88 (L, R).
Leader: Lon D. Abbott, University of Colorado
Cosponsor: GSA Geosciences Education Division
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On this trip, we will journey through the entire geologic history of Denver. Of necessity, the coverage of each chapter in that story is general. The trip is intended for convention attendees who seek a broad overview of the area’s geologic history, for their guests, and for K–12 teachers. We will start by viewing the evocative “Ancient Colorados” paintings at the Colorado Convention Center. From there we head to Red Rocks amphitheater to begin our conversation with the rocks that narrate the story depicted by the paintings. At the amphitheater, we will listen to rocky tales (via our observations of their characteristics) of Denver’s changing landscape between about 1700–250 million years ago. Next, we’ll journey to nearby Dinosaur Ridge, where the rocks pick up the story of Denver from the Jurassic to the middle Cretaceous. From there, we’ll travel to the Colorado School of Mines campus, where we can walk in the footsteps of latest Cretaceous dinosaurs. We will end our journey through time with trips to South Table Mountain and Green Mountain, whose rocks tell stories of the birth of the Rocky Mountains at the dawn of the Cenozoic era.

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Primary leader e-mail: lon.abbott@colorado.edu
Abbott has taught geoscience at the college level for 16 years. Among his publications are three geology books and 13 articles for a popular audience.

Primary Leader Experience
Abbott has led variations of this field trip for college students from three different institutions. His recently published book, Geology Underfoot along Colorado’s Front Range, contains several chapters devoted to the planned stops. Lon has also led numerous other field trips, including ones for K–12 teacher continuing education credit.

419. A Survey of the Depositional Environments, Paleoflora, and Paleofauna of the Western Interior Seaway Greenhorn Cyclothem in the Comanche National Grassland, Southeastern Colorado.
Mon., 28 Oct. US$108 (L, D, R).
Leader: Steven Miller, Western Interior Paleontological Society
Cosponsor: Western Interior Paleontological Society
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This field trip will give participants a look at the geological and sedimentological features that define the Greenhorn Cyclothem—the transgressive and regressive events in the first phase of the Cretaceous Western Interior Seaway. Significant publications on the subject formations are drawn from Kansas, Pueblo, and New Mexico. Here, however, we will see some slight but interesting differences. At the first stop, the Mesa Rica, Pajarito, and Romeroville members clearly illustrate the transition from a shoreline environment that supported terrestrial flora and fauna to a nearshore marine environment: tracks and fossilized impressions of leaves and other plant material, ripples and bioturbation, and cross-bedding all in upward sequence. The second stop will give participants an opportunity to examine the alternating sequences of chalky limestones and fine fissile shales of the middle Greenhorn Formation. Fossils of inoceramus are extremely abundant and densely populate some of the beds. This site also shows how the terrain was altered long after the beds were originally deposited. At the last stop, we will visit the Carlile-Niobrara contact. Participants will have the opportunity to collect fossils from the Juana Lopez member of the Carlile formation under the WIPS Special Use Permit with the USDA Forest Service. Most invertebrate material and limited vertebrate material may be kept by participants. This trip will require some moderate walking over rough grassland. There will be limited access to comfort facilities during the time afield.

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Primary leader e-mail: steve_miller_cs@yahoo.com
Steve is a native of Pennsylvania, a veteran, and an avid outdoor adventurer. He has lived in Pennsylvania, California, and Colorado, where a vocational interest in geology and paleontology grew over time. He works in technology, and has been employed by companies including DEC, Compaq, and HP, and is currently employed at Oracle. Steve and his wife are residents of Colorado Springs.

Primary Leader Experience
Steve has been a member of the Western Interior Paleontological Society (WIPS) since 2004. He has been studying in the Comanche National Grassland area since 2005 and has led over a dozen field trips in coordination with the USDA Forest Service—with annual Special Use Permits. As principal investigator, he has overseen and participated in the following: surveyed and identified exposures of Cretaceous formations across the breadth of the Timpas Unit; surveyed and documented tracks in the Dakota Sandstone as well as invertebrate ichnofossils, and documented leaves and other plant material; conducted detailed stratigraphic measurements. This is an ongoing project started in 2010: Started a project to understand and report on the time-compressed Juana Lopez member of the Carlile, where significant biostratigraphic index fossils are found within 1m locally (and within 106ft at the type section). Collected and identified many different fossil specimens and have begun to associate these in the stratigraphic column—where we find them in situ. Steve is also a student in the Denver Museum of Nature & Science paleontology certification program, working on the field certification.

420. Tour of the Bureau of Reclamation Laboratories, Denver Federal Center.
Mon., 28 Oct. US$57.
Leader: Audrey Hughes Rager, U.S. Bureau of Reclamation
Cosponsor: U.S. Bureau of Reclamation
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Participants will tour the Bureau of Reclamation on the Denver Federal Center campus. This four-acre facility houses the Hydraulic Investigations & Lab Services Group, Environmental Applications & Research Group, and the Materials Engineering & Research Laboratories. The Hydraulic Investigations & Laboratory Services Group provides hydraulic testing, analysis, and research services via laboratory scale modeling, numerical modeling, field testing, analytical studies, and applied research and technology development programs. The Environmental Applications & Research Group conducts studies on riparian and wetland environments and on invasive species such as the quagga and zebra mussels; environmental impact statements; and water quality monitoring and improvement.The Materials Engineering & Research Lab (MERL) has the facilities to test concrete, concrete reinforcement, selected metals, plastics, geotextiles, coatings, and other materials. Tests include physical properties, corrosion, durability, environment, and drying and shrinkage. Petrographic examinations of concrete, aggregate, soils, and foundation rock are also conducted using petrographic microscopes, SEM, and XRD. The tour will culminate with break of a 2-foot × 4-foot concrete cylinder on the five-million pound testing machine. Participants should bring a photo ID and wear closed-toed shoes. International visitors should provide their names, passport numbers, and dates of birth at least two weeks before the tour. Children are welcome to attend when accompanied by an adult. Several of the large-scale hydraulic models are accessed by stairs. Please let us know if you need special accommodations.

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Primary leader e-mail: ahrager@unlv.nevada.edu
Audrey Rager grew up in Denver, Colorado. After graduating from the University of Colorado, Boulder, Audrey moved to Las Vegas to take a job on the Nevada Test Site. While living there for the next 23 years, she worked in GIS and remote sensing, met her husband and a son, and finished her M.S. and Ph.D. After graduation, she took a job with the U.S. Geological Survey. In 2012, she accepted a job as a geologist with the U.S. Bureau of Reclamation Materials Engineering and Research Lab in Denver, Colorado.

Primary Leader Experience
Audrey Hughes Rager received a B.A. in anthropology in 1989 from the University of Colorado, an M.S. in earth science in 2003 from Emporia State University, and a Ph.D. in geology in 2010 from the University of Nevada–Las Vegas. Rager has ten years’ experience in GIS and remote sensing for local and federal government and government contractors. Her dissertation research dealt with the effects of water content on rock fragmentation thresholds during shock decompression. Rager is currently a geologist with the U.S. Bureau of Reclamation specializing in petrology of concrete and concrete aggregate using thin-section analysis, SEM, and XRD.

421. Kirk Bryan Field Trip: Critical Zone Evolution: Climate and Exhumation.
Wed., 30 Oct. US$85 (L, R).
Leaders: Suzanne P. Anderson, University of Colorado–Boulder; David P. Dethier, Gregory E. Tucker, Robert S. Anderson
Cosponsors: Boulder Creek Critical Zone Observatory, GSA Quaternary Geology & Geomorphology Division [ grants available ]
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The architecture of the critical zone—the distribution of mobile regolith, the thickness of weathered rock, and their characteristics, as well as the topography of the land surface—is shaped by erosion and weathering. This trip explores the Boulder Creek watershed in the Colorado Front Range, a landscape strongly shaped by Quaternary climate cycles operating on a template inherited from the Laramide orogeny. Stop one will either be an overview where several alluvial strath terraces on the Plains can be seen or a visit to one of the terraces where cosmogenic radionuclide dating has been used to constrain the timing and rates of exhumation of the Front Range (e.g., Table Mountain, where a NEON soil pit was sampled and is still accessible). At our next stop in Betasso Open Space, we will discuss the impact of the canyon cutting set off by late Cenozoic exhumation of the Plains on the hillslopes and groundwater systems lining the master stream. After lunch, we will hike two miles down Gordon Gulch, a focus site in the Boulder Creek Critical Zone Observatory (CZO). Stops along the way will be used to discuss exhumation rates, climate-modulated weathering, water, and hillslope sediment transport, and the influence of slope aspect on these processes. In the event of snow, we will visit the Mountain Research Station for presentations and discussion. Our goal is to focus on the history of climate-driven erosion and weathering processes and how to build these processes into quantitative models of landscape evolution.

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Primary leader e-mail: suzanne.anderson@colorado.edu
Suzanne Anderson grew up skiing and hiking in the Cascade Mountains in Washington. She found that earth sciences brought together her love of wilderness mountains and science. She is now an associate professor of geography and Fellow of the Institute of Arctic and Alpine Research at the University of Colorado. She has served as the principal investigator of the Boulder Creek Critical Zone Observatory since 2007.

Primary Leader Experience
Anderson earned an M.S. in geology from the University of Washington and a Ph.D. in geology from University of California at Berkeley. She served as a National Science Foundation earth sciences post-doctoral Fellow at the University of Wyoming. Anderson has experience working in the high Arctic, on glaciers in Alaska, in the Oregon Coast Range, and on the Colorado Front Range.

top POSTMEETING

422. Seismogenic Fault-Zone Processes and Heterogeneity Recorded by Pseudotachylyte: New Insights from the Homestake Shear Zone, Colorado.
Thurs., 31 Oct. US$96 (B, L, R).
Leaders: Joseph L. Allen, Concord University; Colin A. Shaw
Cosponsors: GSA Structural Geology and Tectonics Division, GSA Geophysics Division
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Pseudotachylyte is a fault rock generated by frictional melting and is widely interpreted to result from earthquake faulting. This one-day trip will examine Proterozoic pseudotachylyte and mylonite in the Homestake shear zone. Our ongoing research and geologic mapping shows that the shear zone is the largest mapped pseudotachylyte system in the world and uniquely preserves details of earthquake rupture at the fault-system scale. It incorporates a 25-kilometer-long, partitioned system of dip-slip mylonites and strike-slip to oblique-slip pseudotachylytes. The shear zone originated as a high-temperature structure during continental assembly at ca. 1.7 Ga and was reactivated as a subvertical, transpressional system at ca. 1.4 Ga under lower temperatures in a mid-crustal, intracratonic setting. The shear zone was seismogenic in this younger deformation cycle and shows a lateral plastic to frictional strain gradient across a width of 4 to 5 km, from mylonite/ultramylonite with mutually cross-cutting pseudotachylyte, to mylonitic pseudotachylyte, to a system of dispersed pseudotachylyte-bearing fault zones. This trip will examine outcrops demonstrating this strain gradient and discuss implications for coeval plastic flow and earthquake rupture near the base of the seismogenic zone. We will also discuss applications of our work to understanding fine details of earthquake rupture geometry and rupture dynamics at depth. The trip will be of interest to a broad cross section of structural geologists, as well as geophysicists interested in earthquakes and dynamic fracture. The field site is approximately two hours from the Colorado Convention Center and will involve two short but steep off-trail hikes.

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Primary leader e-mail: allenj@concord.edu
Joe Allen is professor of geology at Concord University, where he founded the geology program and has been employed since 1998. He conducted postdoctoral research at the University of Tennessee–Knoxville and completed a Ph.D. at the University of Kentucky. He was co-editor of the 2005 Tectonophysics special issue on “Pseudotachylytes and seismogenic friction.”

Primary Leader Experience
Allen led field trips at the 2002 and 2007 GSA Annual Meetings and has worked for more than two decades on Proterozoic, early Paleozoic, and Laramide deformation associated with the Homestake shear zone in the Sawatch Range, the nearby Grizzly Creek shear zone, and the White River Uplift.

423. Geology along the Rocky Mountain Front Range, Morrison to Golden including Structure, Stratigraphy, Paleontology, Volcanic and Economic Geology (Post-Meeting).
Thurs., 31 Oct. US$107 (L, R).
Leaders: Timothy B. Connors, National Park Service; Norb Cygan
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The geologic strata exposed along the Laramide uplift of this section of the Front Range are exceptionally good examples of late Paleozoic through early Cenozoic history that includes the Denver Basin, overlying Tertiary lava flows, and with few gaps, continuous sediment deposition of Mesozoic rocks. Precambrian rocks are well exposed in this area, with a 1.4 billion year hiatus between the Archean and the Pennsylvanian rocks. Laramide faulting along the Front Range is also important to the geologic story. This field trip will explore the rock exposures of these formations in Golden and Morrison, Colorado. The visitor will come away with an idea of just how the Rockies were formed and discover why we call the Dinosaur Ridge trackways the Dinosaur Freeway. We will also observe economic geology in the area, which includes oil and gas, uranium, and coal and clay mining.

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Primary leader e-mail: tim_connors@nps.gov
Tim Connors obtained geology degrees from the University of Toledo (B.S. 1991 and M.S. 1996) and has been a geologist with the National Park Service Geologic Resources Division, Denver, since 1998. He has spent the last 15 years creating GIS-based geologic maps for National Park Service areas in the lower 48 states, Hawaii, Alaska, and the Virgin Islands. From this experience, he is well versed in the geology of the U.S. and numerous geologic terranes, features, and processes. He also teaches geology at the University of Colorado in Denver. Teaching duties have included physical and historical geology, the geology of Colorado, and teaching courses to science and math teachers as part of the Rocky Mountain Middle School Math and Science Partnership. Tim has also proudly served on the Board of Directors for the Friends of Dinosaur Ridge (Morrison, Colorado) since 1999, and has had a keen interest in the expansion and establishment of the Morrison-Golden Fossil Areas National Natural Landmark (that encompasses Dinosaur Ridge and Fossil Trace Golf Course areas). Tim is mainly a stratigrapher and sedimentary geologist and also enjoys the aspects of data management and presentation as it pertains to distributing geoscience information.

Primary Leader Experience
Tim has proposed, organized, and conducted field trips for academics, lay persons, societies, professional geologists and engineers, and school children since the 1990s. He has vast experience in U.S. geology from visits and trips to more than 100 National Park areas. He has also led trips in Ohio, Colorado, Wyoming, South Dakota, Utah, New Mexico, and Arizona. Most of the trips concerned stratigraphy, sedimentology, paleontology, and paleoenvironment interpretation. He has led and/or participated in several GSA-sponsored field trips for the Friends of Dinosaur Ridge in 1999, 2002, 2007, and 2010 related to Dinosaur Ridge. He has led numerous university groups on various field trips to showcase Colorado and Colorado Plateau geology, Black Hills (South Dakota–Wyoming), Big Horn Basin (Wyoming), and Yellowstone National Park area over the years. He has extensive experience in preparing field trip guides, budgets, lodging arrangements and trip logistics, as well as serving as a driver on several excursions (with 15-passenger van certification from the University of Colorado) with a flawless driving record.

424. Proterozoic Metamorphism and Deformation in the Northern Colorado Front Range.
Thurs., 31 Oct. US$102 (L, R). — Canceled due to flood.
 

425. History of Paleontology at the Florissant Fossil Beds National Monument.
Thurs., 31 Oct. US$105 (L, R).
Leaders: Herbert W. Meyer, National Park Service; Bret L. Buskirk
Cosponsor: The Paleontological Society [ grants available ]
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The late Eocene Florissant fossil beds are world-renowned for their delicate plant and insect fossils and huge petrified redwood stumps. This field trip to Florissant Fossil Beds National Monument will provide an overview of the monument’s history, from the early geologists and paleontologists to the homesteaders who collected the first fossils for science, through the decades of commercial operation of two rival “petrified forest” concessions, to the establishment and operation of the national monument. The prolific scientific history of the site’s study extends back 140 years, beginning with the Hayden Survey. Less known—yet recently revealed in the new book Saved in Time—is the history of the lively legal battle to establish the national monument in 1969, which set new precedents during the infancy of environmental law. We will also discuss the scientific significance of Florissant’s geology and paleontology, emphasizing ongoing research as a focal point of the monument’s mission. Highlights of the trip will include a tour of the new paleontology lab and exhibit hall in the facility that opened in 2013, a one-mile walk through the historic Petrified Forest area, and fossil collecting at a privately owned fossil quarry. Scholarships are available from the Paleontological Society for this trip.

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Primary leader e-mail: Herb_Meyer@nps.gov
Herb Meyer has been the paleontologist at Florissant Fossil Beds National Monument for 19 years. He received his bachelor’s, master’s, and Ph.D. degrees in paleontology from the University of California at Berkeley. His research interests are in fossil plants, paleoclimate, and paleoaltimetry in Colorado, New Mexico, Oregon, and Peru. He has been involved in the conservation of paleontological sites in the U.S., Peru, and China.

Primary Leader Experience
Meyer’s books pertinent to the topic of this field trip include the Fossils of Florissant (Smithsonian Books), Saved in Time: The Fight to Establish Florissant Fossil Beds National Monument (University of New Mexico Press), Paleontology of the Upper Eocene Florissant Formation, Colorado (GSA Special Paper), and Geologic Guidebook to the Gold Belt Byway, Colorado (Gold Belt Association). He has authored many papers and abstracts about Florissant’s paleontology, history, and management, and has been the leader for five previous GSA field trips to Florissant.

426. Strata, Structures, and Enduring Enigmas—A 125th Anniversary Overview of Colorado Springs Geology.
Thurs.–Fri., 31 Oct.–1 Nov. US$187 — Canceled due to flood.

427. New Views on Late Paleozoic Climate and Tectonics in the Ancestral Rocky Mountains.
Thurs.–Sat., 31 Oct.–2 Nov. US$351 (1B, L, R, 2ON).
Leaders: G.S. (Lynn) Soreghan, Univ. of Oklahoma; D.E. (Dustin) Sweet
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Recent research in the Permo-Pennsylvanian strata of the Fountain Formation adjacent to the Front Range uplift and the Cutler Formation adjacent to the Uncompahgre uplift has resulted in the development of new hypotheses bearing on climatic and tectonic interpretations of the Ancestral Rocky Mountains. The Fountain and Cutler formations comprise iconic deposits; the thick and coarse-grained nature of these units has been cited for nearly a century as documenting the former existence of uplifts termed the “Ancestral Rockies.” Long considered the products of alluvial fan deposition, new data hypothesizes the possibility of proglacial deposition for these units, and thus glaciation of the Ancestral Rocky highlands, with significant bearing on our understanding of Late Paleozoic climate in western equatorial Pangaea. Furthermore, new mapping in the Uncompahgre region indicates substantial onlap of Precambrian highlands by Permian strata, thus documenting Permian subsidence of the uplift. Evidence for the latter includes Unaweep Canyon, a geomorphologic enigma of the Uncompahgre Plateau, hypothesized to be a Permian paleolandscape carved glacially. This trip will include visits to (1) the Fountain and Cutler formations to discuss and debate the sedimentologic origin(s) of these deposits; (2) the Permian onlap of the Uncompahgre uplift to examine the evidence for landscape burial here; and (3) Unaweep Canyon to examine evidence for both a possible Paleozoic age and origin for this canyon and its late Cenozoic history as a former stream course of the ancestral Gunnison River.

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Primary leader e-mail: lsoreg@ou.edu
G.S. (Lynn) Soreghan earned a B.S. in geology from UCLA in 1986 and a Ph.D. in geology from the University of Arizona in 1992. She was employed by Amoco (1992–1996) and then joined U.-Oklahoma as an assistant professor in 1996. She has worked at OU since 1996 and is now full professor of geology.

Primary Leader Experience
Soreghan is a field-based sedimentologist. Her research focuses on the Late Paleozoic record of the western U.S. and elsewhere, especially “deep-time” paleoclimate. She has spent many field seasons working on the Late Paleozoic geology of the western U.S., and has been working on the outcrops related to this trip since ca. 2000.

top Associated Society Field Trip

FEES
(in U.S. dollars)
Early Reg.
(1 Aug.–15 Sep.)
Late Reg
(After 15 Sep.)

Members

$795

$895

Non-Members

$895

$995

Member Students

$395

$445

Non-Member Students

$445

$495

Society of Economic Geologists (SEG)

Colorado Porphyry-Molybdenum Deposits and Leadville District.
Thurs.–Sat., 24–26 Oct.
Leaders: Ralph Stegen, Freeport-McMoRan; Tommy Thompson, University of Nevada.
Registration opens 1 August via the SEG website. Note: GSA will not be handling registration for this field trip.

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From Denver, visit the world-class porphyry Mo deposits at Climax and Henderson (Freeport-McMoRan Copper & Gold) and the carbonate-hosted Ag-Zn-Pb manto deposits at Leadville. The Climax and Henderson deposits have been the source of leading research in porphyry Mo deposits and development of exploration methods. The Leadville district is noted for its long history of production, research on carbonate-hosted Ag-Zn-Pb-(Au) deposits, and the founding of the Guggenheim mining fortune, including the formation of ASARCO, Inc. SEG Monograph 7 reported on much of the research on the Colorado Mineral Belt manto systems. Trip will include tour of the Climax and Henderson mines with updates in geology of both, then move to Leadville for numerous stops in the district. Trip will leave Denver and stay overnight in Keystone and Leadville, then return to Denver.

Field Trip Capacity: Minimum 20 / Maximum 30 participants including leaders

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Ralph Stegen
Ralph J Stegen is employed as a vice president for exploration with Freeport-McMoRan Copper and Gold. He is based in Tucson, Arizona and responsible for mine site exploration and resource block model activities at Freeport’s operations in North and South America. Ralph has worked on porphyry Mo and porphyry Cu-Mo deposits since 1985 including time as a geologist and chief geologist at the Morenci and Tyrone porphyry Cu deposits, and at the porphyry Mo deposit at Questa, New Mexico. Since 2006, Freeport has been active in exploration activities at Climax and Henderson. Ralph has been active in the exploration drilling, mapping and resource modeling activities at these deposits. Prior to this, Ralph worked in exploration on carbonate-hosted manto systems in Leadville and Gilman, Colorado and at the Park City and Tintic systems in Utah. His thesis was on geology and geochemistry of the manto deposits at Aspen, Colorado under Dr. Tommy Thompson.

Ralph has been the field leader to SEG-sponsored field trips to the Climax and Henderson deposits in 2006 and 2010. He was the leader for a SEG field trip of the Morenci, Tyrone and Santa Rita porphyry deposits in 2007. Ralph also has lead Arizona Geological Society field trips to Morenci, Tyrone, Santa Rita, and Ajo porphyry copper and Bisbee manto deposits in Arizona.

Tommy Thompson
Tommy B. Thompson received his B.S. (1961), M.S. (1963), and Ph.D. (1966) degrees in Geology from the University of New Mexico.  His first job (Summer, 1961) in the mining business was at the new Sunnyside mine north of Silverton, CO.  On completion of his doctorate Tommy accepted a position at Oklahoma State University where he and John W. Shelton developed the graduate program in Geology.  In 1973 Tommy joined the faculty at Colorado State University to develop the Economic Geology program where he advanced from Associate to Professor and advised more than 70 M.S. and Ph.D. students.  He retired from CSU in 1995 and became a full-time consultant to several companies, working primarily in the Western U.S., Mexico, Perú, Chile, and Argentina.  In 1997 at the urging of mining companies he became the Director of the Ralph J. Roberts Center for Research in Economic Geology (CREG) at the Mackay School of Mines, University of Nevada, Reno, where he served through 2012, and continues as Professor of Economic Geology.

Throughout his teaching-research career Tommy has consulted for more than 40 companies in the Western Hemisphere working on porphyry copper, stockwork molybdenum, carbonate-hosted Zn-Pb-Ag-Au manto deposits, epithermal low- and high-sulfidation systems, uranium-bearing systems, and Carlin-type deposits.  He served from 1986 to 2002 as the first Editor of the SEG Guidebook Series, from 1992-1996 as Councilor, SEG Vice President, and the Publications Committee.  He was the recipient of the SEG Marsden award in 2005.  Tommy co-edited and co-authored papers in the 1990 SEG Monograph 7 on “Carbonate-Hosted sulfide Deposits of the Central Colorado Mineral Belt.”

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