KECK PROPOSAL: Tectonic Evolution of the Teton-Absaroka Ranges, (Year 2)

Project Leaders: John Craddock (Macalester College; [email protected]) and Dave Malone (Illinois State University; [email protected])

Host Institution: Macalester College, St. Paul, MN

Project Dates: ~July 15-August 14, 2011

Student Prerequisites: Structural Geology, Sedimentology.

Preamble: This project is an expansion of a 2010 Keck project that was funded at a reduced level (Craddock, 3 students); Malone and 4 students participated with separate funding. We completed or are currently working on three 2010 projects: 1. Structure, geochemistry and geochronology (U-Pb zircon) of carbonate pseudotachylite injection, White Mtn. (J. Geary, Macalester; note that this was not part of last year’s proposal but a new discovery in 2010 caused us to redirect our efforts), 2. Calcite twinning strains within the S. Fork detachment allochthon, northwest, WY (K. Kravitz, Smith; note because of a heavy snow pack in the Tetons this past summer, we chose a different structure to study), and 3. Provenance of heavy minerals and detrital zircon geochronology, Eocene Absaroka volcanics, northwest, WY (R. McGaughey, Carleton). We did not sample the footwall folds proposed in the previous proposal (under snow) and will focus on this project and mapping efforts of and the 40 x 10 km S. Fork detachment area near Cody, WY, in part depending on the results (calcite strains, detrital zircons) of the 2010-11 effort. All seven students are working on the detrital zircon geochronology project, and two abstracts are accepted at the 2011 Denver GSA meeting.

Overview: This proposal requests funding for 2 faculty to engage 6 students researching a variety of outstanding problems in the tectonic evolution of the Sevier-Laramide orogens as exposed in the Teton and Absaroka ranges in northwest Wyoming. Although the projects that we propose are quite varied in theme, it is important to note that all faculty and students will work as a group for the entire field season, and that all students will participate in at least some level on all of the projects. The Eocene was a time when the thin-skinned Sevier orogen was replaced with the thick-skinned Laramide orogen in the Cordillera, producing a variety of complex, overlapping structures. We will 1. study the strain history of footwall Paleozoic sediments overthrust by Archean gneisses in the and, 2. produce a detailed geologic map of the S. Fork detachment (SFD) allochthon exposed in the S. Fork of the River valley, and 3. complete a geologic map of White Mtn., where we discovered

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enormous vertical injection of carbonate pseudotachylite related to the detachment in 2010. We have also included budget for detrital zircon analyses which will allow us to 1. Finish dating samples collected in 2010 (we’re on the laser in Tucson in early Nov.) or 2. Collect additional samples in 2011 depending on our results from this year, especially the White Mtn. CUC rocks (we’ve found 2 zircon populations).

Introduction Orogenic shortening is accommodated by hanging wall folding above thrust faults, and the Sevier belt (late -Eocene) records this shortening as an orderly “younging toward the craton” sequence of thrust motions with dated synorogenic sediments (Armstrong and Oriel, 1965; Dorr et al., 1977, Wiltschko and Dorr, 1983, Craddock, 1992). The transition from Sevier, east-vergent thin- skinned shortening, with 45° slab dip to the west, to west-vergent, thick-skinned shortening, occurred with decreasing slap (5°) dip in the Eocene (, 1988). These crustal-scale offsets of Archean crust are dated by synorogenic deposits (Gries, 1983; DeCelles et al., 1991; Fuentes et al., 2009) and fission track studies (Roberts and Burbank, 1993; Crowley et al., 2002), and many Laramide uplifts preserve a curious peneplain surface at high elevation (Smith and Seigel, 2000). The zone of overlap between thin and thick-skinned structures is in the vicinity of and the Teton Range. The Heart Mountain detachment system, arguably the largest volcanic landslide deposit (Malone, 1995 and 1996; Craddock et al., 2009; Malone and Craddock, 2008) in the world, is also an Eocene event in the vicinity of Jackson Hole and the greater Absaroka volcanic province. The South Fork detachment system is contemporaneous with the HMD event. Figure 1 is a location map with specific field sites identified; this is correlated to the student project table below (and vice versa).

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Figure 1: Digital elevation (DEM) base of northwest Wyoming. Projects include footwall folds (1a and 1b), mapping the S. Fork detachment (2), and White Mountain (3).

Proposed Projects 1. Laramide Footwall Folds (2 students) Orogenic shortening is accommodated by hangingwall folding above thrust faults. Uplift of the hangingwall ramp-anticline buries the footwall leading geologist’s to presume the footwall is undeformed. Where the footwall rocks are exposed, which is rare, the underlying sediments are usually layered parallel to the thrust with one exception, where complex folds are exposed (Craddock et al., 1985). The Laramide Fourellen fault (and Buck Mtn. fault to the south; Smith, 1991) strikes N-S and dips east along the length of the Teton Range where spectacular exposures of Archean gneisses are in thrust contact with an overturned footwall syncline in -Mississippian sediments (Figures 2a- b). The exposures near Fourellen Peak and Alaska Basin are ideal for studying the strain history of this folded structure (N-S trend, shallow plunges). Both sandstones (quartzites; finite strains) and carbonates (calcite twin analysis on limestone and calcite veins) will preserve the deformation history around the fold curvature and along strike, and results will be compared with strain analyses nearby in the southern Cache Creek thrust sheet (Craddock et al., 1988) as well as the fold strain history of the nearby Derby Dome Laramide uplift (Craddock and Relle, 2003). We may also find syn-faulting calcite that can be

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used to record the stress-strain field when the fault was active (Craddock et al., in review). Oriented samples will be collected throughout for thin section work on the universal stage. Each student project will include field mapping of part of the synclinal structure, sampling and measuring of fault-fold kinematic indicators, and collection of oriented samples for 3-D strain analysis. Strain analysis will involve either using 3 orthogonal oriented sections (ACF method for finite strain ellipsoids) or 1-3 oriented sections for measuring mechanical twins in calcite (limestones and veins).

Fig. 2: Fourellen fault (left), with Archean gneisses over the Cambrian-Pennsylvanian section (photo from Love et al., 2007) and, right, the trace of the same fault placing Archean gneisses over the Cambrian Flathead Sandstone (circled) on the west side of the Teton’s (photo from Smith, 1991).

2. South Fork Detachment Strains and Mapping (2 students) The Heart Mountain Detachment in northwest Wyoming has been the focus of scientific inquiry for more than 100 years. The lesser known South Fork detachment, which is temporally and spatially related to the Heart Mountain detachment, has had much less attention over the years. The South Fork detachment (SFD) is exposed in the drainage of the South Fork of the Shoshone River and along Rattlesnake Creek. Dake (1918) initially described and named the SFF and Pierce further defined and mapped its extent (Pierce, 1957, 1966, 1970; Pierce and Nelson, 1968, 1969). Bucher (1936) first suggested gravity as a driving mechanism for movement and formation of this 10 X 40 km rootless, folded structure (Fig. 3).

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Figure 3: Geologic map of the South Fork Detachment area (from Love and Christianson, 1985, above), and and air photo composite (1”=10 km) of the S. Fork detachment southwest of Cody, WY.

The decollement surface is at the base of the Jurassic Sundance Formation. It ramps up section to the Cody Shale, and ramps once again up section to the Eocene . The South Fork detachment is obscured by younger volcanic rocks to the west and south. As much as 10 km of displacement is indicated and the hanging wall structures (folds) are oriented SW‐NE with shallow plunges. Some bedding is overturned, indicating nappe‐

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like folds, in association with “circular” faults (Fig. 4). Although the motion direction of the South Fork fault seems to align with the presumed displacement direction the Heart Mountain slide block (to the SE), the orientation of pre‐ Cenozoic rocks in the lower plate and those to the southeast and southwest of the upper plate of the fault are consistent with the variable pattern of E‐W Sevier‐ Laramide shortening. The South Fork detachment has been interpreted to be the front of a gravity detachment that is older than and unrelated to the Heart Mountain Detachment (Blackstone, 1985; and Pierce, 1957, 1986), the easternmost expression of the Cordilleran overthrust belt (Clarey, 1990), or the toe of the Heart Mountain detachment (Beutner and Hauge 2009). The data supporting either interpretation are so poorly constrained that new detailed mapping of critical exposures is warranted. Most of the reinterpretations used by Clarey, Beutner, and Hauge used existing mapping of Pierce and his colleagues, which has been called into question by all of the workers in the area for the past 30+ years. The principal scientific question advanced with this subproject is: Does the new detailed geometric (through geologic mapping) and kinematic (through calcite strain analysis) advance the Sevier‐Laramide shortening or the Heart Mountain‐related gravity slide hypothesis? Mapping done as part of this project will be at the 1:24,000 scale on modern base maps in the Twin Creek and Belknap Creek 7.5 Minute Quadrangles. Reconnaissance mapping will be conducted in critical surrounding areas. Students will use a PDA with mobile GIS software to gather the field data. The final geologic maps will be produced at the ISU geospatial laboratory. Kinematic data will be gathered during the mapping and analyzed as part of the students’ research projects. The mapping will support and enhance our current calcite twinning strain analysis of upper plate rocks.

Figure 4: Overturned crossbeds in the Jurassic Morrison Fm. (left) and folded “circular” fault in the SFD (right, view NE).

3. White Mountain Carbonate Pseudotachylite (2 students) White Mountain is the only place in the chaos of the Heart Mountain detachment where the upper plate Madison limestone is altered to marble (+forsterite, brucite) and the basal HMD carbonate ultracataclasite (CUC) is 3 m thick

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(Craddock et al., 2009). From the distance, White Mountain appears to be a gently folded section of Madison limestone with a central trachyandesite stock and many andesitic dikes and sills. Closer investigation has revealed the presence of numerous dikes of CUC that are intruded vertically from the HMD detachment 200-500 feet into the hanging wall carbonates (Fig. 5). Jesse Geary’s project is to characterize the petrographic, textural and compositional (SEM- WDS) and geochemical (XRF, stable isotopes, U-Pb zircon [there are 2 populations]) nature of 6 of the intrusions found to date. Our continued effort will result in a detailed map of White Mountain (last mapped in the 1960s at a scale of 1:62,500) and adjacent area to document the nature of all the CUC intrusions.

Figure 5: Carbonate ultracataclasite intruded vertically parallel to an Eocene andesitic dike (right), both cross-cutting the marbleized Madison Limestone at White Mountain. Hammer for scale.

No. No Project Location* Objective Methods Students Fourellen Calcite thrust N. Teton Strain in footwall twin 1 1 & footwall Range syncline Analysis, fold ACF

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Calcite Buck Mtn. S. Teton Strain in footwall twin 2 thrust & 1 Range syncline Analysis, footwall fold ACF Mapping, S. Fork Sevier-Laramide Calcite Detachment 3 Cody, WY Detachment or twin 2 Mapping and Gravity Slide? analysis; Strains, Sed. DZ Mapping, White Mtn. HMD Calcite Mapping & 4 Sunlight Basin Pseudotachylite twin 2 Structure and field relations analysis; Geochem. DZ [Acronym key: ACF: auto-correlation function to measure strain; HMD= Heart Mtn. detachment and volcanism; DZ= detrital zircon ages. Field sites on Fig. 1].

The group will convene in Denver, acquire rental vehicles, drive to Jackson Hole, WY and will be in the field most of the month camping. We will start with 3-4 days of regional reconnaissance through the Heart Mountain detachment, Yellowstone Park, Jackson Hole and the Tetons, and the northern -Wyoming thrust belt. One part of the group will map in the SFD, joined by the footwall fold and White Mtn. groups as they finish their projects. Thin section tabs will be prepared at Macalester. Heavy mineral and zircon separates will be prepared at Macalester (Craddock), and zircon splits will be sent to the University of Arizona. Those students dating zircons will travel to Tucson in the fall-winter and use George Gehrel’s laserchron lab (student travel and lodging is covered by George’s lab) with either Craddock and/or Malone. Geological maps will be produced at the ISU Geospatial Lab.

Health & Safety Each field party will be equipped with a satellite phone. Cell service is good in the S. Fork valley. White Mountain and the SFD project are accessible by vehicle and on foot, and are nearby to working ranches. The Tetons sites will require backpacking, establishment of a basecamp and day trips. Field sites in the Teton’s are accessible by trail and there is no intent to undertake roped climbing and mountaineering objectives.

Previous Keck Involvement Craddock sponsored Andrea Troolin, who worked on Hank Woodard’s Quetico project in 1992, and attended the annual Keck meeting in Walla Walla, WA with Andrea. Craddock was the PI of the 2005 Minn. project with Karl Wirth (Macalester) and Cam Davidson (Carleton). Publications from

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the efforts of these 9 students are listed below. Craddock was funded for a 3- student project in Wyoming in 2010-11. Malone had no previous Keck involvement, but he and Craddock have worked together for many years on the Heart Mtn. problem.

Keck 1992 #Troolin, A.L., Craddock, J.P. and *Sanchez, C.J., 1993, Multiple slip directions along the Archean Burntside Lake fault system, Quetico province, Ontario: G.S.A. Abstracts with Programs, v. 25, n. 3, p. 55. Keck 2005 Craddock, J.P., *Patel, D., *Porter, R. and Wirth, K.W., 2006, Anisotropy of magnetic susceptibility (AMS) analysis of Keweenaw rift rhyolites, Minnesota: 52 nd Institute on Lake Superior Geology, p. 13-4. #Juda, N., Craddock, J.P., Wirth, K.W., Vervoort, J. and *Andring, M., 2006, Petrogenesis of granite xenolith in the 1.1 Ga Midcontinent rift at Silver Bay, MN: 52 nd Institute on Lake Superior Geology, p. 35-6. Wirth, K.R., Vervoort, J., Craddock, J.P., Davidson, C., *Finley-Blasi, L., #Kerber, L., #Lundquist, R., #Vorhies, S., and #Walker, E., 2006, Source rock ages and patterns of sedimentation in the Lake Superior region: results of preliminary U-Pb detrital zircon studies: 52 nd Institute on Lake Superior Geology, p. 69-71. *Finley-Blasi, L., Davidson, C., Wirth, K.W., Craddock, J.P.,and Vervoort, J.D., 2006, U-Pb detrital zircon from the Neoproterozoic Fondulac and Hinckley Sandstone Fms. Near Duluth, MN: G.S.A. Abstracts w/ Programs, v. 38, n. 7, p. 505. Wirth, K.W., Vervoort, J.D., Craddock, J.P., Davidson, C.,*Finley-Blasi, L., #Kerber, L., #Lundquist, R.,#Vorhies, S., and #Walker, E., 2006, Source rock ages and patterns of sedimentation in the Lake Superior region: results of preliminary detrital zircon studies:, G.S.A. Abstracts w/ Programs v. 38, n. 7, p. 505. Wartman, Jakob, Craddock, J.P., Wirth, K.W., Medaris, G., Vervoort, J.D., & Davidson, C., 2007, Detrital zircon provenance and structural geology of the Hamilton Mound inlier, central WI: 53rd Institute on Lake Superior Geology, p. 87. Konstantinou, A., Wirth, K.R., Craddock, J.P., Davidson, C. and J.D. Vervoort, 2008, Origin of Lake Superior Region Early Paleozoic Super- Mature Quartz Arenites: Evidence from U-Pb Detrital Zircon Ages: G.S.A. Abstracts w/ Programs 40, p. 334. Craddock, J.P. and Rainbird, R., 2009, Detrital Zircon Provenance of the Paleoproterozoic (~2.4-2.2 Ga) Huron and (~2.2-1.8 Ga) Animikie Basins, Southern Margin of Laurentia: International Meeting on Continental Geology and Tectonics (China). Craddock,J.P., Rainbird, R., Davis, W.J., Heaman, L., Vervoort, J.D.,

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Davidson, C., Boerboom, T., Konstantinou, A., Vorhies, S., Kerber, L., and Lundquist, R., Detrital Zircon Provenance of the Neoproterozoic (~2.4-2.2 Ga) Huron and Paleoproterozoic (~2.2-1.8 Ga) Animikie Basins, Southern Margin of Laurentia: GSA Bulletin (in review). Craddock, J. P., Vervoort, J.D., Wirth, K.R., Davidson, C., Konstantinou, A., Finley-Blasi, L., Juda, N.A., and E. Walker, (in internal review), Detrital Zircon Provenance of the Proterozoic Keweenaw Rift, Midcontinent USA. Lithosphere. Keck 2010 Hinds, A., Trela, J., #Kravitz, K., Malone, D., and Craddock, J., 2010. Heavy Mineral Analysis of the Basal Wapiti Formation in the South Fork Shoshone River Valley: Geological Society of America Abstracts with Programs, Vol. 42, No. 5, p. 289.

Calhoun, J., *Geary, J., Schroeder, K., Malone, D., and Craddock, J., 2010. Heavy Mineral Provenance Analysis of Eocene Willwood Formation, , Northwest Wyoming: Geological Society of America Abstracts with Programs, Vol. 42, No. 5, p. 289.

(#-Keck student, female; *-Keck student, male)

# Days Date Day Activity Detail 1 July 15 Mon Intro & Prep Intro Lectures, reading and Trip Prep 2 July 16 Tues Recon. Trip Heart Mtn. 3 July 17 Wed Recon. Trip Heart Mtn.-Yellowstone 4 July 18 Thur Recon. Trip Yellowstone-Jackson Hole 5 July 19 Fri Recon. Trip Thrust Belt- 6 July 20 Sat Recon. Trip Central-West Thrust Belt 7 July 21 Sun Fieldwork Students in Field areas 8 July 22 Mon Fieldwork Students in Field areas 9 July 23 Tues Fieldwork Students in Field areas 10 July 24 Wed Fieldwork Students in Field areas 11 July 25 Thur Fieldwork Students in Field areas 12 July 26 Fri Fieldwork Students in Field areas 13 July 27 Sat Fieldwork Students in Field areas

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14 July 28 Sun Fieldwork Students in Field areas 15 July 29 Mon Fieldwork Student in Field areas 16 July 30 Tues Fieldwork Students in Field areas 17 Aug. 1 Wed Fieldwork Students in Field areas 18 Aug. 2 Thur Fieldwork Students in Field areas 19 Aug. 3 Fri Fieldwork Students in Field areas 20 Aug. 4 Sat Fieldwork Students in Field areas 21 Aug. 5 Sun Fieldwork Students in Field areas 22 Aug. 6 Mon Fieldwork Students in Field areas 23 Aug. 7 Tues Fieldwork Students in Field areas 24 Aug. 8 Wed R&R Day Jackson Hole, Teton Village Lift? 25 Aug. 9 Thur Fieldwork Students in Field areas 26 Aug. 10 Fri Fieldwork Students in Field areas 27 Aug. 11 Sat Fieldwork Students in Field areas 28 Aug. 12 Sun Fieldwork Students in Field areas 29 Aug. 13 Mon Fieldwork Students in Field areas 30 Aug. 14 Tues Fieldwork Students in Field areas 31 Aug. 15 Wed Project Ends Wrap-up and Planning; sample organization

References Antweiler, J.C., Love, J.D., and W.L. Campbell, 1977, Gold content of the Pass Peak Formation and other rocks in the Rocky Mountain overthrust belt, northwestern Wyoming: 29th Field Conference, Wyoming Geol. Assoc., p. 731-749. Armstrong, F.C. and Oriel, S.S., 1965, Tectonic development of the Idaho- Wyoming thrust belt: Am. Assoc. Pet. Geol. 49, 1847-66. Bird, P., 1988, Formation of the Rocky Mtns., western : a continuum computer model. Science 239: 1501-1507. Beutner, E.C. and Hauge, T.A., 2009, Heart Mountain and South Fork fault systems: Architecture and evolution of the collapse of an Eocene volcanic system, northwest Wyoming. Rocky Mountain Geology, v. 44, no. 2 p. 147–164. Blackstone, D. L., Jr., 1985, South Fork detachment fault, Park County, Wyoming: Geometry, extent, source: Contributions to Geology, University of Wyoming, v. 23, p. 47–62.

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Clarey, T. L., 1990, Thin‐skinned shortening geometries of the South Fork fault: , Park County, Wyoming: The Mountain Geologist, v. 27, p. 19–26. Craddock, J.P., Eastman, D.B. and Wiltschko, D.V., 1985, Sequence of deformation events beneath the Bear thrust, Hoback Canyon, western WY: Earth Science Bulletin, v. 18, p. 31-44. Craddock, J.P., Kopania, A. and Wiltschko, D.V., 1988, Interaction between the northern Idaho-Wyoming thrust belt and bounding basement blocks: in, G.S.A. Memoir 171 `Interaction of the Rocky Mountain foreland and the Cordillera thrust belt', C. Schmidt and W. Perry (Editors), p. 333-353. Craddock, J.P. & Relle, M.K., 2003, Fold axis-parallel rotation within the Laramide Derby Dome fold, , WY, Journal of Structural Geology, v. 25, p. 1959-1972. Craddock, J.P., Malone, D.H., Cook, A.L., Rieser, M.E., and Doyle, J.R., 2009, Dynamics of emplacement of the Heart Mountain allochthon at White Mountain: Constraints from calcite twinning strains, anisotropy of magnetic susceptibility and thermodynamic calculations: Geological Society of America Bulletin, v. 121, n. 5, p. 919-938, doi:10.1130/B26340. Craddock, J. P., J. Wartman, M. Kelly, M. Bussolotto, A. Benedicto, and C. Invernizzi, in review, Calcite twinning strains from syn‐faulting gouge along the active Gubbio normal fault, Apennine Mountains, Italy: GSA Bulletin. Crowley, P.D., Reiners, P.W., Reuter, J.M., and G.D. Kaye, 2002, Laramide exhumation of the , Wyoming: an apatite (U‐Th)/He thermochronology study: Geology 30, p. 27‐30. Dake, C.L., 1918, The Heart Mountain overthrust and associated structures in Park County Wyoming: Journal of Geology, v. 26, p. 45‐55. DeCelles, P.G. (and 6 others), 1991, Kinematic history of a foreland uplift from Paleocene synorogenic conglomerate, Beartooth Range, Wyoming and Montana: Geol. Soc. America Bull. 103, p. 1458-1475. Dorr, J.A., Jr., Spearing, and J.R. Steidtmann, 1977, Deformation and deposition between a foreland uplift and an impinging thrust belt, Hoback basin, Wyoming. Geol. Soc. Am. Sp. Paper 177, 82 pp. Fuentes, F., DeCelles, P.G., and G. Gehrels, 2009, Jurassic onset of foreland basin depostion in northwestern Montana: implications for along-strike synchroneity of Cordilleran orogenic activity: Geology 37, p. 379-382. Gries, R., 1983, Oil and gas prospecting beneath the Precambrian of foreland thrust plates in the : Am. Assoc. Pet. Geol. 67, p. 1-26. Krause, M.J., 1983, Genesis of Early Tertiary Exotic Metaquartzite Conglomerates in the Absaroka-Bighorn Region, Northwest Wyoming: Wyoming Geological Association Field Conference Guidebook, Vol. 33. P.103-110.

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Lindsay, D.A., 1972, Sedimentary Petrology and Paleocurrents of the Harebell Formation, Pinyon Conglomerate, and associated coarse clastic deposits, northwestern Wyoming: US Geol. Survey Prof. Paper 734-B. Love, J.D., 1973, Harebell Formation (upper Cretaceous) and Pinyon Conglomerate (uppermost Cretaceous and Paleocene), northwest Wyoming: US Geol. Survey Prof. Paper 734a. Love, J.D. and J.C. Reed, 1968, Creation of the Teton landscape –the geologic story of national park : Teton Natural Hisory Assoc., 120 pp. Love, J.D., E.B. Leopold, and D.W. Love, 1978, Eocene rocks, and geologic history, Teton Range, northwestern Wyoming: US Geol. Survey Prof. Paper 932-B. Love, J.D., Reed, J.C. and K.L. Pierce, 2007, Creation of the Teton Landscape: Grand Teton Assoc. (ISBN 0-931895-57-x), 132 pp. Malone, D.H., and Craddock, J.P., 2008, Recent contributions to the understanding of the Heart Mountain Detachment, Wyoming: Northwest Geology, v. 37, p. 21-40. Malone, D.H., 1995, A very large debris-avalanche deposit within the Eocene volcanic succession of the Northeastern Absaroka Range, Wyoming: Geology, v. 23, no.7, p.661-664. Malone, D. H., 1996, Revised Stratigraphy of Eocene Volcanic Rocks in the Lower North and South Fork Shoshone River Valleys, Wyoming: Wyoming Geological Association Annual Field Conference Guidebook, vol. 47, p. 109- 138. Pierce, W.G., 1957, Heart Mountain and South Fork detachment thrusts of Wyoming: American Association of Petroleum Geologists Bulletin, v. 41, p. 591‐626. Pierce, W.G., 1966, Geologic map of the Cody Quadrangle, Park County, Wyoming: U.S. Geological Survey Quadrangle Map GQ‐542, Scale: 1:62,500. Pierce, W.G., 1970, Geologic map of the Devilʹs Tooth quadrangle, Park County, Wyoming: U.S. Geological Survey Quadrangle Map GQ‐755, Scale: 1:62,500. Pierce, W.G., and Nelson, W.H., 1968, Geologic map of the Pat OʹHara quadrangle, Park County, Wyoming: U.S. Geological Survey Quadrangle Map GQ‐755, Scale: 1:62,500. Pierce, W.G., and Nelson, W.H., 1969, Geologic map of the Wapiti Quadrangle, Park County, Wyoming: U.S. Geological Survey Quadrangle Map GQ‐ 778, Scale: 1:62,500. Rhodes, M.K., Malone, D.H., Carroll, A.R., and Smith, M., 2007, Sudden Desiccation of Lake Gosiute at 49 Ma: A Downstream Effect of Heart Mountain Faulting? The Mountain Geologist, v. 1, p 1-10.

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Roberts, S.V. and D.W. Burbank, 1993, Uplift and thermal history of the Teton Range (northwestern Wyoming) defined by apatite fission –track dating: Earth and Planetary Science Letters 118, p. 295-309. Schmitt, J.G., 1987, Origin of late Cretaceous to early Tertiary quartzite conglomerates in northwestern Wyoming: 38th Field Conf., Wyoming Geol. Assoc., p. 217-224. Smith, D.J., 1991, Structural geology and history of the fault and adjacent intra-range faults, Teton Range, Wyoming: M.S. thesis, Montana State University, 143 pp. Smith, R.B. and L. Seigel, 2000, Windows into the Earth: the geologic story of Yellowstone and Grand Teton national parks: Oxford Univ. Press, NY. Steidtmann, J.R., 1971, Origin of the Pass Peak Formation and equivalent early Eocene strata, central western Wyoming: Geol. Soc. America Bull. 82, p. 156-176. Wiltschko, D.V. and S. Sutton, S., 1981, Deformation by overburden of a coarse quartzite conglomerate: J. of Geology 90, p. 725-733. Wiltschko, D.V, and J.A. Dorr, (1983). Timing of deformation in the overthrust belt of Idaho, Wyoming and Utah: Bull. Am. Assoc. Pet. Geol. 67: 1304- 1322.

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