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Grand Mesa, Uncompahgre, and Gunnison National Forests DRAFT Forest Assessments: Paleontological Resources November 2017

Grand Mesa, Uncompahgre, and Gunnison National Forests DRAFT Forest Assessments: Paleontological Resources November 2017

Department of Agriculture Forest Service , Uncompahgre, and Gunnison National Forests DRAFT Forest Assessments: Paleontological Resources November 2017

Paleontologist Jim Jensen (Brigham Young University) working on large sauropod forelimb replica (Supersaurus) excavated from Dry Mesa dinosaur quarry, Uncompahgre National Forest. In accordance with Federal civil rights law and U.S. Department of Agriculture (USDA) civil rights regulations and policies, the USDA, its Agencies, offices, and employees, and institutions participating in or administering USDA programs are prohibited from discriminating based on race, color, national origin, religion, sex, gender identity (including gender expression), sexual orientation, disability, age, marital status, family/parental status, income derived from a public assistance program, political beliefs, or reprisal or retaliation for prior civil rights activity, in any program or activity conducted or funded by USDA (not all bases apply to all programs). Remedies and complaint filing deadlines vary by program or incident. Persons with disabilities who require alternative means of communication for program information (e.g., Braille, large print, audiotape, American Sign Language, etc.) should contact the responsible Agency or USDA’s TARGET Center at (202) 720-2600 (voice and TTY) or contact USDA through the Federal Relay Service at (800) 877-8339. Additionally, program information may be made available in languages other than English. To file a program discrimination complaint, complete the USDA Program Discrimination Complaint Form, AD-3027, found online at http://www.ascr.usda.gov/complaint_filing_cust.html and at any USDA office or write a letter addressed to USDA and provide in the letter all of the information requested in the form. To request a copy of the complaint form, call (866) 632-9992. Submit your completed form or letter to USDA by: (1) mail: U.S. Department of Agriculture, Office of the Assistant Secretary for Civil Rights, 1400 Independence Avenue, SW, Washington, D.C. 20250-9410; (2) fax: (202) 690-7442; or (3) email: [email protected] (link sends e-mail). USDA is an equal opportunity provider, employer, and lender.

Grand Mesa, Uncompahgre, and Gunnison National Forests DRAFT Forest Plan Assessments: Paleontological Resources

Contents Contents ...... i Chapter 1. Introduction ...... 1 Key Issues for Paleontological Resources on the GMUG ...... 1 Summary Public Input ...... 1 Use of Best Available Science ...... 1 Chapter 2. Condition and Trends ...... 2 Current Condition of Known Paleontological Sites/Localities...... 2 Information Gap regarding Paleontological Resources ...... 2 Chapter 3. Sustainability ...... 7 Environmental Sustainability of Paleontological Resources ...... 7 Economic Sustainability of Paleontological Resources ...... 7 Social Sustainability of Paleontological Resources ...... 7 Chapter 4. Current Forest Plan and its Context ...... 8 Existing Forest Plan Management Direction for Paleontological Resources ...... 8 Chapter 5. Potential Need for Plan Changes to Respond to Paleontological Resource Issues ...... 8 References Cited ...... 9 Appendix A. Paleontological Resources Rapid Assessment System ...... 12 PRRAS value 0 ...... 13 PRRAS value 1 ...... 14 PRRAS value 2 ...... 14 Relation of FYPC Values to New Categorization System ...... 14 PRASS Categorization and Paleontological Resource Management ...... 15

List of Tables Table 1. Paleontological Resource Rapid Assessment System values for GMUG National Forest ...... 17

List of Figures Figure 1. Paleontological Resources Rapid Assessment System map for the GMUG National Forest...... 16

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Grand Mesa, Uncompahgre, and Gunnison National Forests DRAFT Forest Plan Assessments: Paleontological Resources

Chapter 1. Introduction Key Issues for Paleontological Resources on the GMUG A fundamental paleontological resources analysis for the Grand Mesa, Uncompahgre, and Gunnison National Forests (GMUG) has never been completed, such as the Comprehensive Evaluation Reports completed for other resources areas in 2006. Therefore, a base-level understanding of what paleontological localities/sites are known on the GMUG is necessary, as well as predictive potential maps to know the likelihood of encountering significant paleontological resources during ground disturbance. With the exception of one Special Interest Area (Dry Mesa Dinosaur Quarry on the Uncompahgre Plateau), there is no strategic direction for management of the paleontological resources on the GMUG.

Summary Public Input The public is immensely interested in paleontological resources, and the Rocky Mountain Regional Office’s Paleontological Program has an extensive history of providing ‘Cultural Services’ (2012 planning rule, 1909.12, chapter 10, section 13.12 Ecosystem Services) to the country through volunteer stewardship projects. The only site the public (and perhaps many internally) are aware of is the “Dry Mesa Dinosaur Quarry.” Dry Mesa is a highly significant locality managed on the Forest, but Dry Mesa is not an active quarry at present, and emphasis is now on management of extensive collections in partner museums (largely Brigham Young University). However, there are many more paleontological resources on the GMUG, many undiscovered, including vertebrate trackways, plant, and , as well as fossil mammals. There is substantial public input/interest in volunteering to provide responsible management of these resources. Recent inquiry (2015) from the public ( Springs Mineralogical Society) about opportunities for “casual collecting” (fossils) and rock-hounding (rocks and minerals) on surrounding forests (Rio Grande and San Juan) has revealed inaccurate information on some Forest Service interpretive panels. These panels should be updated to reflect current Rules (36 CFR 291, April 17, 2015) under current Law (PRPA, Paleontological Resources Preservation Act, 2009), and the potential presence of such inconsistencies should be reviewed on GMUG interpretive information (panels, brochures, internet).

Use of Best Available Science Numerous peer-reviewed geological/paleontological publications have been drawn upon to develop an initial, and quickly hewn, predictive modeling system for the occurrence of paleontological resources on the GMUG. Historical ‘soft policy’ referred to this system as the Fossil Yield Potential Classification (FYPC). New policy in the Paleontological Program, in progress, has revamped the FYPC, and in its place developed the Paleontological Resources Rapid Assessment System (PRRAS) for short (Appendix I, Figure 1, Table 1). This system is simpler to understand and implement than previous ‘soft policy.’

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Much of the base geologic information comes from the State Geologic Map of Colorado in Arc/Info Format (Tweto, 1979; Green, 1992). Geologic units (, Formation, Member, subunits) are treated as delineated on the Tweto (1979) map. PRRAS values (0, 1, 2) are assigned by the regional paleontologist based upon literature review, consultation with partner universities and museums, communication with researchers in various applicable geologic strata, and ground reconnaissance. The use of Best Available Science herein follows the Executive Memorandum issued by President Barak Obama (March 9, 2009) regarding scientific integrity. Chapter 2. Condition and Trends Current Condition of Known Paleontological Sites/Localities Historically, relatively little attention has been devoted to paleontological resources management on federal lands. The Forest Service currently employs three obligate paleontologists, roughly 0.0001%, or one-ten thousandth of the workforce. Obviously then, the responsible treatment of paleontological resources as required under the PRPA and National Environmental Policy Act (NEPA) of 1969 is a broad-brush effort, with more intensive management focused on known issues. The Paleontological Program does not, and cannot, function in a compliance management mode given the miniscule workforce. The program relies, where appropriate, upon assistance from other resource specialists. But detailed paleontological assessments, reviews for permits, or “Determinations” require an obligate “qualified paleontologist” (terms as defined in the PRPA subtitle and preamble). Increasing the paleontological workforce is not likely in the near future. The nature of other resource area programs (e.g. air, water, archaeology, biology) are driven by statutes with powerful environmental mandates. The PRPA, which directs management of paleontological resources, is expressly not an environmental law, containing explicit “Savings Provisions” (Section 6311) language that restricts the degree to which paleontological resources are considered as authorized by the PRPA. Therefore, the program will continue to be treated as a fundamental stewardship responsibility within the Forest Service, and function largely in a proactive (cultural services), rather than a reactive (compliance) management, mode. Broad language within NEPA is pertinent to paleontological resources (42 U.S.C. 4321, sec. 101(b) (4): “Preserve important natural aspects of our national heritage”).

Information Gap regarding Paleontological Resources As stated above, a fundamental and comprehensive paleontological resources assessment for the GMUG has never been completed. This document will merely provide a rough framework for accumulation and assimilation of information compiled from the field through paleontological permit reports, and/or specialist assessment during NEPA assessments. The present knowledge of geologic units on the GMUG and their potential to produce paleontological resources is summarized below. Only geologic units with PRRAS (Appendix I) values of 1 or 2 are addressed below. Units with PRRAS values of 0 are unlikely to contain paleontological resources.

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Harding – Age The is classically known to produce some of the earliest vertebrate material in North America (Graffin, 1992), including chitino-phosphatic external armor of early bony (ostracoderms). The best known localities are on and around Bureau of Land Management lands near Canon City; however, Harding exposures on the GMUG could also contain similar fossil forms. • PRRAS value – 2

Manitou Dolomite (or ) – Ordovician Age The Manitou Dolomite is known to produce some of the only trilobite fossils known in the State of Colorado. In particular, a locality on the Pike National Forest (near Decker) has been extensively studied (Wagner, 2009). In addition to trilobites, the deposit also contains cystoids, brachiopods, and gastropods. Exposures of the Manitou on the GMUG likely also contain such fossil forms. • PRRAS value – 2

Leadville Limestone, Dyer Dolomite – Lumped Ordovician – Units

Leadville Limestone – Age The Leadville Limestone is a broadly distributed marine unit throughout the Rocky Mountains, correlating to similar units in other areas (e.g. Pahasapa Limestone of the Black Hills, South Dakota). The Leadville commonly contains marine macroinvertebrates including brachiopods, bryozoans, and crinoids (Armstrong and Mamet, 1976). • PRRAS value – 1

Dyer Dolomite – Devonian Age The Dyer Dolomite is known to be abundantly fossiliferous on the White River National Forest (Flat Tops area), and there are in-depth biostratigraphic studies ongoing in cooperation with the Denver Museum of Nature and Science (Hagadorn, 2016). The Dyer produces a diverse array of micro- and macroinvertebrates, as well as vertebrate fossil (armored fish, chondrichthyan teeth). Dyer exposures on the GMUG are likely to contain similar fossils. • PRRAS value – 2

Minturn Formation – Age The Minturn (and Belden) formations are known to produce vast numbers of macroinvertebrate fauna, representative of a diverse reef complex, on the Salida Ranger District (RD), San Isabel National Forest (Bassam Park). This aspect of the Minturn/Belden formations was recently written into the Presidential Proclamation for Browns Canyon National Monument (Obama, 2015). Extensive studies of the Minturn/Belden fossil deposits on the Salida RD were undertaken by the University of Colorado Denver from 2002 through 2007 in partnership with the Forest Service (Houck, 2007). • PRRAS value – 1, 2

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Pennsylvanian Hermosa Group The Hermosa Group consists of the basal Pinkerton Trail, the Paradox, and the Honaker Trail Formations. The Hermosa is a complex assemblage of marine and continental sediments that were deposited cyclically in the central basin and on the margins of the Paleozoic (Condon, 1992). The Hermosa ranges in thickness from roughly 120 to 850 m, and various subunits are known to contain fusilinids, crinoids, and other invertebrate fossils. Although the paleontological resources are common, their biostratigraphic age utility have immense scientific value. Such fossils are likely present in expression of the Hermosa on the GMUG; however, there is not yet (2016) field verification of this. • PRRAS value – 1

Pennsylvanian/ – Age Poorly Constrained Composed mainly of red beds of sandstone, , mudstone, , and claystone with some thin beds of gray limestone, the Maroon Formation varies between 90 to 120 m in thickness. This unit is a prominent red sandstone expressed in many places throughout the . At the top of the Maroon Formation is the Schoolhouse Member, a light- gray to green and reddish-brown feldspathic sandstone and conglomeratic sandstone. A location on the White River National Forest (Maroon Bells) is known to contain hundreds of vertebrate tracks, some invertebrate traces, and plant impressions in the Maroon Formation (Voigt et al., 2005). Previously, the Maroon Formation was not known to be fossiliferous, with the exception of marine at the base of the formation, and its age had been poorly constrained, typically described simply as Pennsylvanian/Permian. The Maroon fossil assemblage from the White River National Forest is important because its four vertebrate ichnotaxa are similar to all four of the Tambach vertebrate ichnotaxa from Germany, strengthening the faunal ties recently established between the Tambach Formation and some Early Permian redbeds in North America. Similar such localities could occur on the GMUG. • PRRAS value – 1

Permian – Early Permian (Wolfcampian) Age From oldest to youngest, members include the Halgaito , Organ Rock Shale, and the De Chelly Sandstone. There is no designated type locality for the Cutler. It was named by Cross and Howe in 1905 after Cutler Creek, which enters Uncompahgre River about 4 miles north of Ouray, Colorado. Baker and Reeside (1929) divided the formation into the Halgaito Tongue (base), Member, Organ Rock Tongue, and Member. At the surface in the San Juan River area, the upper part of the lower Cutler beds (previously included in the Halgaito Formation) is brick red and consists mainly of interbedded very fine grained silty sandstone and sandy siltstone. Some sandier or more calcareous beds weather to ledges, but as a whole the unit forms a slope below the Cedar Mesa Sandstone (Condon, 1997). A few thin, gray, nodular limestone beds that pinch and swell along strike are present near the base of the unit. Some thin fluvial channels contain limestone pebble conglomerates, and paleosols are present throughout the section. Vaughn (1973) summarized the vertebrate fauna in these strata and stated that the vertebrate fossils are confined to stream-channel

4 Grand Mesa, Uncompahgre, and Gunnison National Forests DRAFT Forest Plan Assessments: Paleontological Resources deposits. The fauna includes abundant fresh-water sharks, rhipidistian crossopterygian fish, actinopterygian fish, lungfish, amphibians, and primitive . The flora of this interval includes Calamites, arborescent lycopods, and seed ferns (Vaughn, 1973). • PRRAS value – 1

Triassic Chinle Group – (including the Dolores Formation of previous works) Upper strata in southwestern Colorado were originally referred to as the Dolores Formation and typically were divided into three informal members. However, the Dolores Formation can be correlated with Chinle Group units in nearby southeastern and northeastern (Lucas and Heckert, 2005). The “lower member of the Dolores Formation” is as much as 30 m of greenish-gray to tan, fine-grained quartzose sandstone and calcrete-pebble conglomerate, which locally contains siliceous pebbles. It rests unconformably on the Lower Permian Cutler Group and is demonstrably correlative to the Moss Back Formation of the Chinle Group in southeastern Utah (Lucas and Heckert, 2005). The overlying “middle member of the Dolores Formation” is as much as 90 m of grayish red siltstone, mudstone, trough-crossbedded fine-grained sandstone and limestone-pebble conglomerate. The conglomerate beds are the “saurian conglomerates” of earlier works and yield phytosaurs and other vertebrate fossils of Revueltian (Norian) age (Lucas, 1993). This interval is also known to produce plant remains including conifers and palm-like forms (Brown, 1956). The “upper member of the Dolores Formation” is as much as 177 m of repetitively bedded light brown and reddish brown siltstone and sandy siltstone, including paleosols. The stratigraphic position, lithotypes, and paleontology of the “upper member” equate it to the Rock Point Formation of the Chinle Group in adjacent states (Lucas and Heckert, 2005). • PRRAS value – 2

Jurassic The Morrison Formation is a world renowned deposit for and other vertebrates. The unit consists of 100 m or more of interlayered clayston paleosols, channel sandstone, and minor amounts of lacustrine limestone. On the Uncompahgre National Forest, the Dry Mesa Dinosaur Quarry is among the most famous Jurassic dinosaur quarries known in North America. Myriad systematic and paleo-ecological publications about this site have been published over the past decades (e.g. Jensen, 1985; Curtice and Stadtman, 2001; Foster, 2007; many more). Such dinosaur/ names as Mesacactylus, Supersaurus, and Ultrasauros have their origin at Dry Mesa. The bulk of Dry Mesa collections are at Brigham Young University. Anywhere the Morrison exists on the GMUG has potential to contain similar rich fossil deposits. • PRRAS value – 2

Cretaceous Dakota Sandstone – (and Burro Canyon Subunit) The Dakota Sandstone is renowned for producing a diverse assemblage of dinosaur and other reptile trackways in Colorado and surrounding states, and many such localities are known on

5 USDA Forest Service the Pike-San Isabel National Forest (Lockley et al., 1992; Schumacher, 2003; Lockley et al., 2010; Lockley and Schumacher, 2014). The Dakota Sandstone also produces a variety of fossil angiosperm leaves and various other trace fossils. However, for its relative thickness the Dakota Sandstone produces fossils only at discrete intervals/bedding planes; thus, a majority of exposures are not fossiliferous. • PRRAS value – 1

Mancos Shale – , Cenomanian – Campanian Age The is dominantly of marine origin and consists of more than 200 m of (shale and claystone) with minor amounts of limestone and sandstone. Classically, or perhaps typically, the Mancos Shale was long considered to be a rather unfossiliferous geologic interval. However, recent discoveries in Utah (Grand Staircase) have revealed significant vertebrate skeletons of marine reptiles in the correlative Tropic Shale (Albright et al., 2007). And recently, the Museum of Western Colorado has become involved with an elasmosaur skeleton in the Mancos Shale of west-central Colorado (Schumacher correspondence with J. Foster (Director, Museum of Moab, 2015). • PRRAS value – 1

Mesaverde Formation The Mesaverde Formation consists of a regressive series of marine to fluvial deposits greater than 1,000 m in thickness, including massive, tan, ledge-forming sandstone and beds in the lower part, and interbedded light gray sandstone and gray shale in the upper part (Pierce, 1997). Grading up out of the marine Mancos Shale, the shoreline record substages of the regression as delta lobes were activated and abandoned in Colorado during time (Lorenz, 1982). The Formation is classically known for producing an assemblage of Cretaceous micro-mammal fossils () that provide detailed biostratigraphic zonation of the Cretaceous Period (Lillegraven and McKenna, 1986). The unit also produces dinosaur fossil material and footprints (Lockley et al., 1982) from the Grand Mesa coal field. • PRRAS value – 2

Wasatch Formation – to Age The on the west slope of Colorado may be separated into three subunits (Donnell, 1969). The upper and lower members, Shire and Atwell Gulch respectively, are dominantly variegated claystones. The intervening Molina Member consists principally of thick, brown, ledge-forming massive sandstones with thin interbeds of variegated claystone. The lower 200 feet of the Atwell Gulch Member contains Paleocene plant and vertebrate fossils. No fossils have been reported from the Molina or the upper part of the Atwell Gulch Member; however, the Shire Member contains middle early and late early Eocene vertebrate fossils. Grand Mesa and Gunnison National Forests contain several vertebrate fossil-producing Wasatch localities, including a rich site at Mud Hill. • PRRAS value – 2

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Green River Formation – Eocene age The records sedimentation in a group of intermountain in three basins along the present-day Green River in Colorado, Wyoming, and Utah. The sediments are dominantly lime mudstone deposited in very fine layers, often lacustrine varves, and record a continuous record of some six million (Grande and Bucheim, 1994). In particular places, such as Fossil Butte National Monument in Wyoming, the Green River Formation is renowned for producing thousands of fossil fish, as well as complete skeletons of rarer vertebrate animals including gars, turtles, bats, and . In places the unit also preserves exquisite plant and fossils as carbonaceous impressions. • PRRAS value – 2

Cave Deposits – – Recent Age Rich fossiliferous deposits are known in several places on the GMUG, including Cement Creek and Signature caves (Emslie and Meltzer, 2007; Emslie et al., 2009). Such deposits provide a rich paleo-ecological record of the Pleistocene – transitional period, and thus have important implications with respect to climate change. Other such deposits are likely yet undiscovered on the GMUG. The bulk of collections from Cement Creek and Signature are housed at the Denver Museum of Nature and Science. • PRRAS value – 2 Chapter 3. Sustainability Environmental Sustainability of Paleontological Resources The current body of GMUG information regarding paleontological resources expressed at the surface is severely wanting. Improving upon this base knowledge in subsequent years will have a decidedly positive effect on sustainability. The current condition is that the GMUG does not have an obligate paleontologist on staff; therefore, local science staff from other areas, in particular Minerals and Geology Program personnel, can greatly assist in improving sustainable management efforts. Sustainable in this regard means being aware of significant paleontological resources or substantial paleontological deposits at the surface in need of management attention, or those in the shallow subsurface that could be negatively impacted by ground-disturbing activities.

Economic Sustainability of Paleontological Resources The cultural services aspect of paleontological resources management through volunteer stewards and partners (museums, universities) can have a small but measureable positive effect on GMUG communities.

Social Sustainability of Paleontological Resources Having an obligate paleontological resources specialist to serve the GMUG and surrounding forests would enhance opportunities for volunteer stewardship. Social sustainability in this

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regard would help ensure that high-quality educational experiences through volunteer stewardship are available. Chapter 4. Current Forest Plan and its Context Existing Forest Plan Management Direction for Paleontological Resources The only direction for paleontological resources in the current 1991 GMUG plan, as amended, is with respect to the Dry Mesa Dinosaur Quarry Special Interest Area (SIA): Dry Mesa Dinosaur Quarry, Paleontological Site - The quarry is a 40 acre site located within the Jurassic Morrison formation and contains fossils with a geologic age of approximately 150,000,000 years. This quarry is located 26 miles southwest of Delta. Excavation activity has yielded remains of many different kinds of extinct animals including partial skeletons of animals not previously known to science. Specific standards and guidelines pertain to the Dry Mesa SIA, including discouraging/prohibiting any public use which contributes to impairment of research or educational values; and providing signage for interpretation and protection at the site. No signage occurs at Dry Mesa, so there is a need to determine where/if interpretive signing is still desired. The remainder of Forest plan direction for Special Interest Areas also applies to the Dry Mesa Quarry, including a visual quality objective of “modification” (outdated scenery management terminology); the prohibition of construction of developed recreation sites; direction to withdraw the areas from mineral entry in accordance with section 204 of FPLMA; and more. See also the Designated Areas assessment for additional information. To- date, Dry Mesa has not been withdrawn from mineral entry. Assessment of minerals and geology in the plan is purely a commodities-based approach. There is no expressed evaluation of paleontological resources, and no standards or guidelines for paleontological resources management or treatment are offered under the Forest Plan, with the exception of the one SIA. Chapter 5. Potential Need for Plan Changes to Respond to Paleontological Resource Issues A need exists for long-term, baseline efforts to understand and quantify the paleontological resources that are present on the GMUG. Furthermore, consider revised strategic direction to provide interpretation of these resources in a manner appropriate to their preservation for future generations; this might include web- based interpretation. Consider revised/updated strategic direction for the Dry Mesa Special Interest Area, including revisiting the direction to provide interpretive signage at the site. To date, such signage has not been installed. Furthermore, to-date, the area has not been withdrawn from mineral entry.

8 Grand Mesa, Uncompahgre, and Gunnison National Forests DRAFT Forest Plan Assessments: Paleontological Resources Localities of significant paleontological resources that are known include: Mud Hill Locality – northern-most Grand Mesa, and ridge separating GMUG/White River; reconnaissance by Forest Service staff and Denver Museum in 2009. Eocene Wasatch Formation, rich locality of vertebrate material including abundant gar scales and turtle shell fragments, crocodilian bones and teeth, and large mammalian ungulates (~Creodonts). Also numerous phosphatic nodules, likely coprolites. Cement Creek Cave – rich Pleistocene cave deposit includes diverse fauna of Pleistocene mammals; many internal reports are available from Dr. Steve Emslie of the University of North Carolina. Extensive collections from location in Denver Museum. Hunter/Monuments Reservoirs – recent NEPA efforts to assess enlargement of reservoirs revealed Wasatch-age vertebrate remains at both locations. McCurry Reservoir – Wasatch/Uinta vertebrate material, Lianne Mattson, February 2010 Wasatch/Uinta localities – numerous isolated locations reported by Liz Mauch/Lianne Mattson in 2009/2010 Dry Mesa Dinosaur Quarry – one of the most famous fossil localities anywhere in the National Forest System. Worked from the late 60s/early 70s until early in the 21st century. This quarry has produced hundreds of partial bones and skeletons of dinosaurs, pterosaurs, and other freshwater vertebrates. Has been the subject of countless peer-review publications, from specific remains to taphonomy of the site as a whole. The dinosaur Supersaurus and Ultrasauros were first discovered and named here. Also a ramphorhyncid pterosaur (flying reptile) named from Dry Mesa, Mesadactylus. Enormous collections of Dry Mesa fossil material are housed at Brigham Young University. There is potential for future research activities here; however, the site is currently reclaimed to protect the fossil resources and there is no active field research. References Cited Albright, L.B., III, Gillette, D.D., and Titus, A.L. (2007). Plesiosaurs from the Upper Cretaceous (Cenomanian–Turonian) Tropic Shale of southern Utah, part 2: Polycotylidae. Journal of Vertebrate Paleontology 27:41–58. Armstrong, A.K., and Mamet, B.L. (1976). Biostratigraphy and regional relations of the Mississippian Leadville Limestone in the San Juan Mountains, southwestern Colorado. U.S. Geological Survey Professional Paper 985, 25 pp. Baker, A., and Reeside, J.B., Jr. 1929. Correlation of the Permian of southern Utah, northern Arizona, northwestern , and southwestern Colorado. American Association of Petroleum Geologists Bulletin, v. 13, no. 11:1413-1448. Brown, R.W. (1956). Palmlike plants from the Dolores Formation (Triassic), southwestern Colorado. U.S. Geological Survey Professional Paper 274-H, pp. 205–209. Condon, S.M. (1992). Geologic framework of pre-Cretaceous rocks in the Southern Ute Indian Reservation and adjacent areas, southwestern Colorado and northwestern New Mexico. In: Geology and Mineral Resources of the Southern Ute Indian Reservation: U.S. Geological Survey Professional Paper, 1505–A, pp. A1–A56.

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Condon, S.M. (1997). Geology of the Pennsylvanian and Permian Cutler Group and Permian in the Paradox Basin, southeastern Utah and southwestern Colorado. U.S. Geological Survey Bulletin 2000–P, pp. 1–59. Cross, C.W. and Howe, E. (1905). Geography and general geology of the quadrangle, IN Description of the Silverton quadrangle (Colorado), U.S. Geological Survey Geologic Atlas of the United States, Silverton folio, no. 120, 34 pp. Curtice, B., and Stadtman, K. (2001). The demise of Dystylosaurus edwini and a revision of Supersaurus vivianae. In: McCord, R.D., and Boaz, D. (eds.). Western Association of Vertebrate Paleontologists and Southwest Paleontological Symposium – Proceedings 2001. Mesa Southwest Museum Bulletin 8, pp. 33–40. Donnell, J.R. (1969). Paleocene and Lower Eocene units in the southern part of the Piceance Creek Basin, Colorado. U.S. Geological Survey Bulletin 1274-M, 18 pp. Emslie, S.D., Mclean, B., and Meltzer, D. (2009). Field report, Excavations at Signature Cave, Gunnison County, Colorado. Under Temporary Special-Use Permit GUN766, 8 pp. Emslie, S.D., and Meltzer, D. (2007). Excavations of Cement Creek Cave, Colorado. Report of Field Investigations 2007. Under Temporary Special Use Permit FS–2700–4, 8 pp. Foster, J. (2007). Appendix Jurassic West: The dinosaurs of the Morrison Formation and their world. Indiana University Press. pp. 327–329. Graffin, G. (1992). A new locality of fossiliferous Harding Sandstone: Evidence for freshwater Ordovician vertebrates. Journal of Vertebrate Paleontology 12(1):1–10. Grande, L., and Bucheim, P. (1994). Paleontological and sedimentological variation in early Eocene Fossil . Contributions to Geology, University of Wyoming 30, 45 pp. Green, G.N. (1992). The digital geologic map of Colorado in ARC/INFO format: U.S. Geological Survey Open-File Report 92-507. Hagadorn, J. (2016). Denver Museum, paleontological assessment on White River National Forest, 2015 Annual Report to U.S. Forest Service. Challenge Cost Share Agreement No. 13-CS-11021500-017, 10 pp. Houck, K. (2007). A tropical sea floor at 9000 feet: New discoveries from a Pennsylvanian marine fossil locality (Bassam Park fossil beds) in San Isabel National Forest, Colorado. Report to U.S. Forest Service under agreement # 06-CS-11021202-021, 117 pp. Jensen, J.A. (1985). Three new sauropod dinosaurs from the Upper Jurassic of Colorado. Great Basin Naturalist 45:697–709. Lillegraven, J.A., and McKenna, M. (1986). Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River Basins. American Museum of Natural History Novitates no. 2840, New York, 68 pp. Lockley, M.G., Fanelli, D., Honda, K., Houck, K. and Mathews, N.A. (2010). waterways and dinosaur freeways: Implications of multiple swim track assemblages from the Cretaceous Dakota Group, Golden area, Colorado: New Mexico Museum of Natural History and Science Bulletin 51:137–156.

10 Grand Mesa, Uncompahgre, and Gunnison National Forests DRAFT Forest Plan Assessments: Paleontological Resources Lockley, M.G. Holbrook, J., Hunt, A., Matsukawa, M., and Meyer, C. (1992) The dinosaur freeway: a preliminary report on the Cretaceous Megatracksite, Dakota Group, Rocky Mountain Front Range and High Plains, Colorado, Oklahoma, and New Mexico. In: Flores, R. (ed.), Mesozoic of the Western Interior. Society of Economic Paleontologists and Mineralogists Midyear Meeting Fieldtrip Guidebook, pp. 39–54. Lockley, M. and Schumacher, B.A. (2014). A new pterosaur swim tracks locality from the Cretaceous Dakota Group of eastern Colorado: Implications for Pterosaur swim track behavior. New Mexico Museum of Natural History Bulletin 62:365–372. Lockley, M.G., Young, B.H., and Carpenter, K. (1982). Hadrosaur locomotion and herding behavior: Evidence from footprints in the Mesaverde Formation, Grand Mesa Coal Field, Colorado. The Mountain Geologist 20(1):5–14. Lorenz, J.C. (1982). Sedimentology of the Mesaverde Formation at Rifle Gap, Colorado and implications for gas-bearing intervals in the subsurface. United States. doi:10.2172/5313562. Lucas, S.G. (1993). The Chinle Group: Revised and biochronology of Upper Triassic nonmarine strata in the western United States: Museum of Northern Arizona Bulletin 59:27–50. Lucas, S.G., and Heckert, A. (2005). Mesozoic stratigraphy at Durango, Colorado. New Mexico Geological Society, 56th Field Conference Guidebook, pp. 160–169. Obama, B. (2015). Presidential Proclamation - - Browns Canyon National Monument. The White House, Office of the Press Secretary, released February 19, 2015. Pierce, W.G. (1997), Geologic map of the Cody 1 degree x 2 degree quadrangle, northwestern Wyoming: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-2500, scale 1:250000. Schumacher, B.A. (2003). An addition to the Dinosaur Freeway Megatracksite, Dakota Group (Upper Cretaceous), Bent County, Colorado. Ichnos 10:255–262. Tweto, O. (1979). Geologic map of Colorado. U.S. Geological Survey, Map G77115. Vaughn, P.P. (1973). Vertebrates from the Cutler Group of Monument Valley and vicinity. In: James, H.L., ed., Guidebook of Monument Valley and Vicinity, Arizona and Utah: 24th New Mexico Geological Society Field Conference, pp. 99–105. Voigt, S., Small, B., and Sanders, F. (2005). A diverse terrestrial ichnofauna from the Maroon Formation (Pennsylvanian-Permian), Colorado: Biostratigraphic and paleoecological significance. New Mexico Museum of Natural History and Science Bulletin 30:342–351. Wagner, S. (2009). Annual report on the invertebrate fossils of the Manitou Formation north of Woodland Park, Colorado. U.S. Forest Service Special Use Permit (SUP): #PPK334, 17 pp.

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Appendix A. Paleontological Resources Rapid Assessment System1 PRRAS

Definitions & Implementation Guidelines (pending formalization into agency policy)

This document follows-up and expands on the preceding “FYPC Extinction” position paper, which placed development of the FYPC system in a historical context, discussed the deficiencies of the FYPC system, and proposed the need for a new system of paleontological resource categorization that reflects the strong statutory paleontological resources management mandate embodied by the enactment of Paleontological Resources Preservation Act (PRPA, “the Act”) in 2009. A description of the new paleontological resources categorization system, herein termed the Paleontological Resources Rapid Assessment System (PRRAS), including system implementation protocols, is presented below. PRPA stipulates that: “The Secretary [of Agriculture and Interior] shall manage and protect paleontological resources on Federal land using scientific principles and expertise” (16 USC 470aaa—1), and “The Secretary [of Agriculture and Interior] shall develop appropriate plans for inventory, monitoring, …of paleontological resources… .” (16 USC 470aaa—1). Notwithstanding these mandates, the majority of National Forest System (NFS) lands have not been systematically surveyed for paleontological resources. Qualified agency paleontologists are few, and agency financial support for 3rd party paleontological resource field inventories does not exist. Consequently, Forest Service paleontologists have developed the PRRAS to generate indicators of paleontological resources on NFS lands in the short term in response to PRPA paleontological resource management mandates. PRRAS indicators are not substitutes for field surveys; rather, they focus attention on areas where

1 Considerations in development of this name: The Forest Service Paleontological Program is focusing on a quick, science-based evaluation of a geologic unit’s capacity to contain paleontological resources based on intrinsic features of lithology, age, and demonstrated occurrence (where that information can be or has been obtained). The PRRAS system is intended to perform with a minimum of subjective interpretation. “Paleontological resources” because that is what the Forest Service manages, even though “fossils” is a shorter and more intuitive descriptor. “Rapid Assessment” because that describes what the methodology does: provide a quick and reasonably quantified assessment. The degree to which the system is quantified depends upon knowledge of the paleontologist, and reliance upon partner researchers and institutions. In the ‘digital age’ of peer reviewed literature, providing such rapid assessments has become easier to do but still requires an obligate specialist to accurately develop. The PRRAS is a “System” because it is dynamic and results are subject to change with acquisition of additional knowledge. It should NOT be called a “classification,” as doing so will inevitably draw comparisons to FYPC/PFYC (existing Forest Service/Bureau of Land Management ‘soft policy’).

12 Grand Mesa, Uncompahgre, and Gunnison National Forests DRAFT Forest Plan Assessments: Paleontological Resources paleontological resource management is merited and where field surveys should be required to inventory, monitor, and ensure paleontological resource protection. In contrast to paleontological resource distribution, the geology underpinning most NFS lands is generally well-known, having been systematically mapped at a 1:500,000 scale or larger by the USGS, State Geological Surveys, and/or other entities. The foundation premise of the PRRAS is that geology may be used as a proxy mirroring the distribution of paleontological resources. This is because paleontological resources are derived largely from rocks (less commonly unconsolidated or poorly consolidated sediments), and the distribution of paleontological resources in rock/sediment units is fundamentally related to objective attributes such as lithology and geologic age. The PRRAS recognizes three fundamental categories to which geological units may assigned, reflecting likelihood of occurrence or demonstrated occurrence of paleontological resources in those units. A three-category system significantly condenses the broad spectrum of paleontological resource occurrences in rock units, thereby simplifying categorization and reducing employment of arbitrarily-defined categories (i.e. – significance) that lack objective criteria for recognition. The three PRRAS categories are: (a) geologic units that are unlikely to contain paleontological resources and/or where prior paleontological resource studies have demonstrated their non-occurrence, (b) geologic units that are likely to contain paleontological resources and/or where prior paleontological resource studies have demonstrated their occurrence, and (c) geologic units of unknown capacity to contain paleontological resources and lacking prior paleontological resources studies; such geologic units require additional information to determine whether or not they contain, or are likely to contain, paleontological resources. For convenience in tabulating PRRAS category assignments, the categories may be assigned single digit numeric codes as follows: 0=paleontological resources absent or unlikely to occur, 2=paleontological resources present or likely to occur, and 1=likelihood of paleontological resource occurrence unknown. Criteria for assignment of PRRAS categories: PRRAS values reflect fundamental lithologic and geologic age attributes of geologic units, supplemented by any combination of literature, “ground-truth” field survey, and/or personal knowledge concerning the occurrence of paleontological resources in the subject units. Suggested guidelines for PRRAS category assignments are as follows:

PRRAS value 0 • Crystalline igneous rocks (ex. granite, diorite, gabbro) of any age, high grade metamorphic rocks (ex. gneiss, schist) of any age, and sedimentary rocks of Mesoproterozoic () age and older should be assigned a default PRRAS code of 0, having no or negligible potential to contain paleontological resources. Local stromatolite-bearing and/or microfossil-bearing Precambrian sedimentary rocks whose fossil content provide information about the history and early diversification of life on earth should be assigned a PRRAS code of 2. Local cave or fissure fill deposits containing paleontological resources in otherwise unfossiliferous settings such as lava tubes, fissure fills, or karst horizons may also be assigned a PRRAS code of 2.

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PRRAS value 1 • Phanerozoic low-grade metamorphic rocks (e.g. marble, slate), Phanerozoic volcaniclastic igneous-sedimentary rocks (e.g. bentonite, tuff), and Phanerozoic representing depositional environments generally inimical to life and/or the preservation of fossil evidence of life (e.g. deep sea chert, boulder conglomerate, glacial diamictite, eolian ) should be assigned a default PRRAS code 1, having an unknown potential to contain paleontological resources. Site-specific attributes of such units, generally based on prior study, may locally change the code to 0 or 2 (e.g. units similar to the Ashfall Fossil Beds of Nebraska, which document catastrophic mortality and superb preservation of Tertiary vertebrates in volcaniclastic ashfall tuff, would be coded 2). Eolianites such as the of Colorado and Utah are other good examples of geologic units that may be largely devoid of fossils, but in certain locations may contain dinosaur skeletal material, eggs and nests, and (or) footprints. Also, although the Mancos Shale contains hundreds of feet of monotonous including only fish scales and common invertebrate fossils, occasionally significant fossil skeletons of sharks, bony fish, and/or marine reptiles may occur.

PRRAS value 2 • Phanerozoic and (latest Precambrian including Ediacaran) sedimentary rock facies representing depositional environments conducive to life and/or preservation of fossil evidence of life (facies including, but not limited to, most marine shelf/platform depositional systems, fluvial, lacustrine, and glacial continental depositional systems, deltaic depositional systems, and facies transitional between marine, deltaic, and continental depositional systems) all have potential to contain paleontological resources and are assigned a default PRRAS code of 2. Relation of FYPC Values to New Categorization System Substantial historical effort has been directed to assigning significance-based FYPC values to geologic units in a number of Forest Service administrative areas. Despite limitations of the FYPC system, such FYPC ranks may generally be assigned to one of the three PRASS categories described above, which are more broadly and more objectively defined than FYPC classes. Such reassignment of available FYPC values will substantially lessen the program resources required to implement the PRRAS. FYPC and PRRAS equivalencies are as follows: • FYPC class 1 units may be assigned to PRRAS category 0. • FYPC class 2 units may be assigned to PRRAS categories 0 or 1, reflecting the basis of the original FYPC assignment ( units assigned to FYPC class 2 would generally be assigned to PRRAS category 1). • FYPC classes 3, 4, and 5 may be reassigned to PRRAS category 2. • FYPC Class 3-unknown (= PFYC 3b) would be assigned to PRRAS category 1.

14 Grand Mesa, Uncompahgre, and Gunnison National Forests DRAFT Forest Plan Assessments: Paleontological Resources PRASS Categorization and Paleontological Resource Management Generally, geologic units with a PRASS categorization of 0 would not require a field paleontological survey to be performed in advance of surface-disturbing activities because of the negligible likelihood of containing paleontological resources. Geologic units with a PRRAS categorization of 2 would require a field paleontological survey to be performed in advance of surface-disturbing activities. Documentation of the actual distribution of paleontological resources and, where merited, mitigation of potential impacts to such resources, would be responsive to the statutory requirements for paleontological resource management established in PRPA. Geologic units with a PRASS categorization of 1 require additional assessment to determine whether or not a field survey would be merited in advance of surface-disturbing activities. Recognition that PRPA requires management of paleontological resources does not imply that all paleontological resources merit the same level of management. Management decisions concerning paleontological resources should consider resource-specific, location- specific, and project- specific factors, which would include the attributes of the subject paleontological resources, existing and potential uses of those resources, and the nature of potential impacts to those resources.

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Figure 1. Paleontological Resources Rapid Assessment System map for the GMUG National Forest

16 Grand Mesa, Uncompahgre, and Gunnison National Forests DRAFT Forest Plan Assessments: Paleontological Resources

Table 1. Paleontological Resource Rapid Assessment System values for GMUG National Forest [FYPC, Fossil Yield Potential Classification]

Original Unit Age FYPC Unit Name Total Acres Label Ash-flow tuff of late- Tbrt Tertiary 1 1,693 volcanic bimodal suite Ash-flow tuff of main Taf Tertiary 1 191,505 volcanic sequence Basalt flows and associated tuff, breccia, Tbb Tertiary 1 and conglomerate of 67,206 late-volcanic bimodal suite Basaltic intrusive rocks Tbbi Tertiary 1 108 related to basalt flows Early Biotitic gneiss, schist, Xb 1 14,733 and migmatite Felsic and hornblendic Early Xfh 1 gneisses, either 62,555 Proterozoic separate or interlayered Granitic rocks of 1400- and 1700-m.y. age groups, undivided, or, in Early-Middle Taylor River region, YXg 1 136,101 Proterozoic rocks with characteristics of Xg but U-Th-Pb zircon ages of Yg Middle Granitic rocks of 1400- Yg 1 13,204 Proterozoic m.y. age group Early Granitic rocks of 1700- Xg 1 80,850 Proterozoic m.y. age group Intra-ash flow andesitic Tial Tertiary 1 20,635 lavas Intra-ash flow Tiql Tertiary 1 35,238 latitic lavas Tertiary- TKi 1 Laramide intrusive rocks 6,837 Cretaceous Early Mafic rocks of 1700-m.y. Xm 1 2,061 Proterozoic age group Middle Tertiary intrusive Tmi Tertiary 1 132,147 rocks Pre-ash-flow andesitic Tpl Tertiary 1 lavas, breccias, tuffs, 494,953 and conglomerates Rhyolitic intrusive rocks Tbr Tertiary 1 and flows of late- 3,213 volcanic bimodal suite Upper Tertiary intrusive Tui Tertiary 1 58 rocks

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Original Unit Age FYPC Unit Name Total Acres Label H2O 1 water 3,171 Quaternary- QTa 2 Ancient 9,410 Tertiary Qe Quaternary 2 Eolian deposits 2,879 Qd Quaternary 2 Glacial drift 231,438 Qg Quaternary 2 Gravels and 11,335 Ql Quaternary 2 Landslide deposits 181,536 Qa Quaternary 2 Modern alluvium 2,345 Qdo Quaternary 2 Older glacial drift 1,051 Older gravels and Qgo Quaternary 2 567 alluviums Telluride conglomerate Tertiary- of Eocene prevolcanic PRRAS TKec 2 1,287 Cretaceous sedimentary rocks (Te) 0 acres and Cimarron Ridge Fm Early-Middle YXu 2 Uncompahgre Fm 1,206 1,709,320 58% Proterozoic Pc Permian 3a Cutler Fm 1,161 @d Triassic 3a Dolores Fm 1,050 Dolores Fm and Cutler @Pdc Triassic-Permian 3a 2,054 Fm Leadville Limestone, Devonian- Gilman Sandstone, Dyer MD 3a 589 Ordivician Dolomite, and Parting Fm Leadville Limestone, Williams Canyon Mississippian- M_ 3a Limestone , Manitou 37,572 Limestone, and Sawatch Quartzite Leadville Limestone, Williams Canyon Limestone, and one or Mississippian- MDO 3a more of: Fremont 5,153 Ordovician Limestone, Harding Sandstone, and Manitou Limestone Permian- P&m 3a Maroon Fm 37,867 Pennsylvanian Eocene prevolcanic Te Tertiary 3b 6,986 sedimentary rocks &h Pennsylvanian 3b Hermosa Fm 794 Dakota Sandstone and Kdb Cretaceous 4 218,884 Burro Canyon Fm Dakota Sandstone or Kd Cretaceous 4 6,616 Group Tg Tertiary 4 Green River Fm 6,921 Green River Fm--Lower Tgl Tertiary 4 17,215 Part

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Original Unit Age FYPC Unit Name Total Acres Label Green River Fm-- Tgp Tertiary 4 Parachute Creek 16,876 Member Km Cretaceous 4 Mancos Shale 174,788 Minturn Fm in west- &m Pennsylvanian 4 central and south- 77 central and other units sedimentary Tos Tertiary 4 3,739 rocks &b Pennsylvanian 5 Belden Fm 0 @c Triassic 5 Chinle Fm 6,848 Cretaceous- Dakota and Morrison KJdm 5 1,020 Jurassic Fms Dakota, Burro Canyon, Cretaceous- KJdj 5 Morrison, and Junction 16,256 Jurassic Creek Fms Dakota, Purgatoire, Morrison, Ralston Creek, and Entrada Fms in southeast. Dakota, Morrison, and Entrada Cretaceous- KJde 5 Fms in central 12,599 Jurassic mountains. Dakota, Burro Canyon, Morrison, Wanakah, and Entrada Fms in Gunnison River area. Dakota, Morriso Kayenta Fm, Wingate @kc Triassic 5 Sandstone, and Chinle 17,131 Fm Mesaverde Fm, Kmv Cretaceous 5 95,183 undivided or Kmvu Cretaceous 5 7,992 Fm--Upper part &mb Pennsylvanian 5 Minturn and Belden Fms 25,679 Jm Jurassic 5 Morrison Fm 704 Morrison Fm and Jme Jurassic 5 169 Entrada Sandstone Morrison Fm and Jmj Jurassic 5 Junction Creek 4,561 Sandstone Morrison Fm and Wanakah Fm (Junction Creek Sandstone Jmw Jurassic 5 Member at or near top; 1,892 Pony Express Limestone Member at base) Morrison Fm, Jmse Jurassic 5 Summerville Fm, and 211,725 Entrada Sandstone

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Original Unit Age FYPC Unit Name Total Acres Label Morrison, Wanakah, and Jmwe Jurassic 5 7,544 Entrada Fms Tu Tertiary 5 Uinta Fm 15,294 Wasatch Fm (including Fort Union equivalent at Two Tertiary 5 210,086 PRRAS 1–2 acres base) and Ohio Creek Fm and @wc Triassic 5 73,939 1,246,967 42% Chinle Fm Total Acres 2,956,287

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United States Department of Agriculture Forest Service Grand Mesa, Uncompahgre, and Gunnison National Forests 2250 South Main Street Delta, CO 81416 www.fs.usda.gov/gmug/

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