sign in sign up
<<
Home , Almond Formation, Bridger Formation, Browns Park Formation, Chadron Formation, Chugwater Formation, Cloverly Formation

U.S. Department of the Interior Bureau of Land Management

Paleontological Resources Technical Report Riley Ridge to Natrona Project DECEMBER 2018

Table of Contents

1.0 Introduction ...... 1

2.0 Regional Setting ...... 1

3.0 Inventory Methodology ...... 1

4.0 Potential -Bearing Geologic Formations ...... 4 4.1 (PFYC 3) ...... 4 4.2 White Formation or Group (PFYC 5) ...... 5 4.3 Formation (PFYC 5) ...... 5 4.4 (PFYC 5) ...... 5 4.5 (PFYC 5) ...... 5 4.6 Battle Spring Formation (PFYC 3)...... 6 4.7 (PFYC 5) ...... 6 4.8 Crooks Gap (PFYC 3) ...... 6 4.9 (PFYC 3) ...... 6 4.10 Mesaverde Formation or Group (PFYC 3) ...... 6 4.11 (PFYC 5) ...... 6 4.12 Lewis (PFYC 5) ...... 7 4.13 (PFYC 3) ...... 7 4.14 Mowry and Thermopolis (PFYC 3) ...... 7 4.15 Cloverly, Morrison, and Sundance Formations (PFYC 5) ...... 7 4.16 (PFYC 3) ...... 7 4.17 Chugwater and Dinwoody Formations (PFYC 3) ...... 7 4.18 Segment 1: Riley Ridge Treatment Plant to the Proposed Riley Ridge Sweetening Plant ...... 8 4.19 Segment 2: Proposed Riley Ridge Sweetening Plant to the Bairoil Interconnect ...... 9 4.20 Segment 3: Bairoil Interconnect to the Lost Cabin/Natrona Hub Interconnect ...... 9

5.0 Literature Cited ...... 11

Tables

Table 4-1 Geological Units and Associated Potential Fossil Yield Classification in the Study Area ...... 8

Riley Ridge to Natrona Project i November 2018 Paleontological Resources Technical Report THIS PAGE INTENTIONALLY LEFT BLANK

List of Acronyms and Abbreviations

Applicant Riley Ridge LLC and PacifiCorp, doing business as Rocky Mountain Power

BLM Bureau of Land Management

CO2 carbon dioxide

Denbury Riley Ridge LLC

PFYC potential fossil yield classification Project Riley Ridge to Natrona Project (also RRNP)

RRNP Riley Ridge to Natrona Project

Riley Ridge to Natrona Project iii November 2018 Paleontological Resources Technical Report

THIS PAGE INTENTIONALLY LEFT BLANK

1.0 Introduction The Bureau of Land Management (BLM) prepared this technical report for paleontological resources to support the preparation of an Environmental Impact Statement in response to three applications for right- of-way submitted by Riley Ridge LLC (Denbury) and PacifiCorp, doing business as Rocky Mountain Power (collectively referred to as the Applicant), for the Riley Ridge to Natrona Project (RRNP or Project). The Applicant’s proposal to construct and operate the Project, including the underground carbon dioxide (CO2) pipeline system and Riley Ridge Sweetening Plant, the 230-kilovolt transmission line, injection wells, and ancillary facilities.

The paleontological resources found within the 2-mile-wide study corridors of the Project and alternative routes representing the affected environment are described in this technical report. 2.0 Regional Setting The Project would cross the Greater Green River Basin, the Beaver Divide, and the . Both basins have a wide variety of and geological units that have been known to produce in the past. The Greater Green River Basin was filled with and fluvial and lacustrine sediments (Murphey and Daitch 2007). The Wind River Basin consists mostly of Eocene basin-fill sediments in the flat-lying, lower areas with belts of folded , Paleozoic, and Mesozoic rocks forming the flanks and cores of the adjacent mountain ranges (Keefer 1970). The escarpment called the Beaver Divide (Beaver Rim) is at the southern margin of the Wind River Basin and mostly includes a series of Tertiary sediments (Emry 1975). 3.0 Inventory Methodology Information for the paleontological inventory was obtained from a review of the scientific literature and geologic maps, a record search from the Department of and Geophysics at the University of , a Paleontological Resource Assessment previously done for the Project (Erathem-Vanir Geological Consultants 2012), and a geology resource report (SCWA 2014). Agencies contacted include the U.S. Geological Survey, BLM, and Wyoming State Geological Survey.

Information about the geological units and known fossil localities were used to identify the paleontological potential in areas that would be affected by the Project. Paleontological potential levels were assigned to each geological unit using the potential fossil yield classification (PFYC) adopted by the BLM for assessing paleontological potential on federal lands (WO IM 2016-124). The PFYC is a five- tiered system (1 to 5) classifying geological units based on relative abundance of fossils or scientifically significant invertebrate fossils and plant fossils, and their potential to be adversely affected, with a higher class number indicating a higher potential. This classification is applied to a , member, or other distinguishable map unit, preferably at the most detailed level that can be mapped. It is not intended to be applied to specific paleontological localities or small areas within the units.

Although significant localities may occasionally occur in a geologic unit, a few widely scattered important fossils or localities do not necessarily indicate a higher class; instead the relative abundance of significant localities is intended to be the major determinant for the class assignment. Because of the direct relationship that exists between paleontological resources and the geological units they are found within, and by knowing the geology of an area and the fossils previously found in a geological unit, it is possible to predict where fossils likely would be found. The PFYC system is meant to provide baseline guidance for predicting, assessing, and mitigating paleontological resources. The classification should be

Riley Ridge to Natrona Project 1 November 2018 Paleontological Resources Technical Report

considered at an intermediate point in the analysis and should be used to assist in determining the need for further mitigation assessment actions (WO IM 2016-124). Each class is defined as follows:

Class 1 – Very Low. Geologic units that are not likely to contain recognizable fossil remains. ▪ Units that are igneous or metamorphic, excluding reworked volcanic ash units. ▪ Units that are Precambrian in age or older. (1) Management concern for paleontological resources in Class 1 units is usually negligible or not applicable. (2) Assessment or mitigation is usually unnecessary except in very rare or isolated circumstances.

The probability for impacting any fossils is negligible. Assessment or mitigation of paleontological resources is usually unnecessary. The occurrence of significant fossils is non-existent or extremely rare.

Class 2 – Low. Sedimentary geologic units that are not likely to contain vertebrate fossils or scientifically significant nonvertebrate fossils. ▪ Vertebrate or significant invertebrate or plant fossils not present or very rare. ▪ Units that are generally younger than 10,000 before present. ▪ Recent aeolian deposits. ▪ Sediments that exhibit significant physical and chemical changes (i.e., diagenetic alteration). (1) Management concern for paleontological resources is generally low. (2) Assessment or mitigation is usually unnecessary except in rare or isolated circumstances.

The probability for impacting vertebrate fossils or scientifically significant invertebrate or plant fossils is low. Assessment or mitigation of paleontological resources is not likely to be necessary. Localities containing important resources may exist, but would be rare and would not influence the classification. These important localities would be managed on a case-by-case basis.

Class 3 – Moderate or Unknown. Fossiliferous sedimentary geologic units where fossil content varies in significance, abundance, and predictable occurrence; or sedimentary units of unknown fossil potential. ▪ Often marine in origin with sporadic known occurrences of vertebrate fossils. ▪ Vertebrate fossils and scientifically significant invertebrate or plant fossils known to occur intermittently; predictability known to be low.

(or)

▪ Poorly studied and/or poorly documented. Potential yield cannot be assigned without ground reconnaissance.

Class 3a – Moderate Potential. Units are known to contain vertebrate fossils or scientifically significant nonvertebrate fossils, but these occurrences are widely scattered. Common invertebrate or plant fossils may be found in the area, and opportunities may exist for hobby collecting. The potential for a project to be sited on or impact a significant fossil locality is low, but is somewhat higher for common fossils.

Class 3b – Unknown Potential. Units exhibit geologic features and preservational conditions that suggest significant fossils could be present, but little information about the paleontological resources of the unit or the area is known. This may indicate the unit or area is poorly studied, and field surveys may uncover significant finds. The units in this Class may eventually be placed in another Class when sufficient survey and research is performed. The unknown potential of the

Riley Ridge to Natrona Project 2 November 2018 Paleontological Resources Technical Report

units in this Class should be carefully considered when developing any mitigation or management actions.

(1) Management concern for paleontological resources is moderate; or cannot be determined from existing data. (2) Surface-disturbing activities may require field assessment to determine appropriate course of action.

This classification includes a broad range of paleontological potential. It includes geologic units of unknown potential, as well as units of moderate or infrequent occurrence of significant fossils. Management considerations cover a broad range of options as well, and could include predisturbance surveys, monitoring, or avoidance. Surface-disturbing activities will require sufficient assessment to determine whether significant paleontological resources occur in the area of a Proposed Action, and whether the action could affect the paleontological resources. These units may contain areas that would be appropriate to designate as hobby collection areas due to the higher occurrence of common fossils and a lower concern about affecting significant paleontological resources.

Class 4 – High. Geologic units containing a high occurrence of significant fossils. Vertebrate fossils or scientifically significant invertebrate or plant fossils are known to occur and have been documented, but may vary in occurrence and predictability. Surface disturbing activities may adversely affect paleontological resources in many cases.

Class 4a. Unit is exposed with little or no soil or vegetative cover. Outcrop areas are extensive with exposed bedrock areas often larger than two acres. Paleontological resources may be susceptible to adverse impacts from surface disturbing actions. Illegal collecting activities may impact some areas.

Class 4b. These are areas underlain by geologic units with high potential but have lowered risks of human-caused adverse impacts and/or lowered risk of natural degradation due to moderating circumstances. The bedrock unit has high potential, but a protective layer of soil, thin alluvial material, or other conditions may lessen or prevent potential impacts on the bedrock resulting from the activity. ▪ Extensive soil or vegetative cover; bedrock exposures are limited or not expected to be impacted. ▪ Areas of exposed outcrop are smaller than two contiguous acres. ▪ Outcrops form cliffs of sufficient height and slope so that impacts are minimized by topographic conditions. ▪ Other characteristics are present that lower the vulnerability of both known and unidentified paleontological resources.

(1) Management concern for paleontological resources in Class 4 is moderate to high, depending on the Proposed Action. (2) A field survey by a qualified paleontologist is often needed to assess local conditions. (3) Management prescriptions for resource preservation and conservation through controlled access or special management designation should be considered. (4) Class 4 and Class 5 units may be combined as Class 5 for broad applications, such as planning efforts or preliminary assessments, when geologic mapping at an appropriate scale is not available. Resource assessment, mitigation, and other management considerations are similar at this level of analysis, and impacts and alternatives can be addressed at a level appropriate to the application.

Riley Ridge to Natrona Project 3 November 2018 Paleontological Resources Technical Report

The probability for impacting significant paleontological resources is moderate to high, and is dependent on the Proposed Action. Mitigation considerations must include assessment of the disturbance, such as removal or penetration of protective surface alluvium or soils, potential for future accelerated erosion, or increased ease of access resulting in greater looting potential. If impacts on significant fossils can be anticipated, on-the-ground surveys prior to authorizing the surface disturbing action will usually be necessary. Onsite monitoring or spot-checking may be necessary during construction activities.

Class 5 – Very High. Highly fossiliferous geologic units that consistently and predictably produce vertebrate fossils or scientifically significant invertebrate or plant fossils, and that are at risk of human-caused adverse impacts or natural degradation.

Class 5a. Unit is exposed with little or no soil or vegetative cover. Outcrop areas are extensive with exposed bedrock areas often larger than two contiguous acres. Paleontological resources are highly susceptible to adverse impacts from surface disturbing actions. Unit is frequently the focus of illegal collecting activities.

Class 5b. These are areas underlain by geologic units with very high potential but have lowered risks of human-caused adverse impacts and/or lowered risk of natural degradation due to moderating circumstances. The bedrock unit has very high potential, but a protective layer of soil, thin alluvial material, or other conditions may lessen or prevent potential impacts on the bedrock resulting from the activity.

▪ Extensive soil or vegetative cover; bedrock exposures are limited or not expected to be impacted. ▪ Areas of exposed outcrop are smaller than two contiguous acres. ▪ Outcrops form cliffs of sufficient height and slope so that impacts are minimized by topographic conditions. ▪ Other characteristics are present that lower the vulnerability of both known and unidentified paleontological resources.

(1) Management concern for paleontological resources in Class 5 areas is high to very high. (2) A field survey by a qualified paleontologist is usually necessary prior to surface disturbing activities or land tenure adjustments. Mitigation will often be necessary before and/or during these actions. (3) Official designation of areas of avoidance, special interest, and concern may be appropriate. The probability for impacting significant fossils is high. Vertebrate fossils or scientifically significant invertebrate fossils are known or can reasonably be expected to occur in the impacted area. On-the-ground surveys prior to authorizing any surface disturbing activities will usually be necessary. Onsite monitoring may be necessary during construction activities. 4.0 Potential Fossil-Bearing Geologic Formations Potential fossil-bearing geologic formations occurring in the study area are described in this section. 4.1 Browns Park Formation (PFYC 3) The Age Browns Park Formation overlies the Green River and Washakie Formations. It consists of gray, fine- to coarse-grained Tuffaceous and interbedded gray- to-white tuff, gray , and gray and red mudstone. Fossils are rare in the Browns Park Formation but some mammalian fossils have been located (Honey and Izett 1988, Murphey and Daitch 2007).

Riley Ridge to Natrona Project 4 November 2018 Paleontological Resources Technical Report

4.2 or Group (PFYC 5) In Wyoming, the White River Formation, which is Eocene to in age, consists of three members: the lower Chadron Member, the intermediate Brule Member, and the informally designated upper conglomeratic member (Erathem-Vanir 2012). The lithostratographic package is treated as a formation in , Wyoming, and but is accorded group status in and (Erathem-Vanir 2012). It is composed of volcaniclastic and siliciclastic sediments deposited in fluvial, lacustrine, and eolian environments (Zanazzi and Kohn 2008). The White River Group has produced a large mammalian fauna, including brontotheres, artiodactyls, , equids, , rhinoceratids, eomyids, oreodonts, rodents, and bats, as well as marsupials and (Kihm 1987, Zanazzi and Kohn 2008, Emry and Korth 2012, Erathem-Vanir 2012). 4.3 Wind River Formation (PFYC 5) The Eocene Age Wind River Formation consists of variegated to drab claystone and siltstone with interbedded lenticular to sheetlike sandstone beds (Soister 1968). Fossils found in the Wind River Formation include tilodonts, taenidonts, cimolestids, arctocyonids, artiodactyls, rodents brontotheres, horse, and primates, as well as reptiles and plants (Robinson 1966, Williamson et al. 1996, Erathem- Vanir 2012). 4.4 Green River Formation (PFYC 5) The Green River Formation is a large formation covering parts of northeastern , northwestern Colorado, and southwestern Wyoming. The Green River Formation represents a series of Eocene : Uinta, Lake Gosiute, and Fossil Lake, formed of intermontane basins by uplift of the (Grande 1984). The Green River Formation, in the Green River Basin of Wyoming, comprises the Luman Tongue, Scheggs Bed of Tipton Shale Member, Rife Bed of Tipton Shale Member, Member, LaClede Bed of Laney Member, and undivided Sand Butte and Hartt Cabin Beds of the Laney Member (Roehler 1992). Typical lithologies of the Green River Formation include soft to moderately resistant light-gray and buff marlstone, , , siltstone, sandstone, conglomerate, and tuff. The accumulation of fossils occurs throughout its distribution although quality of preservation, abundance, and diversity varies both geographically and stratigraphically (Murphey and Daitch 2007). 4.5 Wasatch Formation (PFYC 5) The Wasatch Formation was mostly deposited in a fluviatile environment and interfingers extensively with the lacustrine deposits of the Green River Formation in Utah, Colorado, and Wyoming (Murphey and Daitch 2007). The Wasatch Formation includes the Chappo and LaBarge members and the unnamed Main Body and is Paleocene to Eocene in age. It is composed of soft light-gray, red, green, white, yellow, and purple claystone, sandstone, siltstone, and conglomeratic sandstone (Rowley et al. 1985, Murphey and Daitch 2007). Throughout its distribution, the Wasatch Formation has produced scientifically significant fossils, although the preservation and abundance of fossils vary regionally and stratigraphically (Murphey and Daitch 2007). Fossils from the Wasatch Formation include condylarths, perrisodactyls, artiodactyls, pantodonts, insectivores, marsupials, reptiles, mollusks, and plants (Murphey and Daitch 2007, Erathem-Vanir 2012). A previous search for known fossil localities in the study area identified three localities in the Wasatch, Battle Spring, or Sundance Formations. These localities included teeth, mammalian tooth root, and a mammalian canine (Erathem-Vanir 2012).

Riley Ridge to Natrona Project 5 November 2018 Paleontological Resources Technical Report

4.6 Battle Spring Formation (PFYC 3) The Battle Spring Formation consists of an arkosic sequence of friable conglomerate, conglomeratic sandstone, and sandstone that was deposited in a deltaic-fluviatile environment (Stephens 1964). The Battle Spring Formation intermingles with the Wasatch and Green River formations. Fragmentary plant fossils and fragmentary vertebrate fossils have been found in the Battle Spring Formation (Stephens 1964, Erathem-Vanir 2012). 4.7 Bridger Formation (PFYC 5) The Middle Eocene Bridger Formation consists of three members: Black Forks Member, Twin Buttes Member, and Bluff member. Its depositional environment includes fluvial, lacustrine, playa lacustrine, paludal, marginal mudflat, basin margin, and volcanic deposits. The Bridger Formation comprises limestone, tuffs, and Tuffaceous sheet (Murphey and Daitch 2007). Numerous fossils have been found in the Bridger Formation, including plants, mollusks, fish, amphibians, reptiles, and (Murphey and Daitch 2007, Murphey and Evanoff 2011). 4.8 Crooks Gap Conglomerate (PFYC 3) The Eocene Crooks Gap Conglomerate consists mainly of granite boulders embedded in pink to gray arkosic sandstone and siltstone. The Crooks Gap Conglomerate may be equivalent to the Wind River Formation and lies with angular on the lower part of the Battle Spring Formation (Love 1970, Schmitt 1979). 4.9 Fort Union Formation (PFYC 3) The Paleocene Fort Union Formation is mainly marine and consists of sandstone, shale, clay and . Several members have been recognized in the Fort Union Formation depending on the region. In Wyoming, the members of Fort Union that have been recognized are the Blue Gap Member, the China Butte member, the Kingsbury Conglomerate Member, the Kleenburn Member, the Lebo Member, the Shotgun Member, the Member, the Tullock member, and the Waltman Shale Member. Fossils found in the Fort Union Formation include plants, amphibians, reptiles, and mammals (Brown 1958, Sullivan 1982, Johnson 1986). 4.10 Mesaverde Formation or Group (PFYC 3) The is a highly variable sequence of sandstone, siltstone, shale, carbonaceous shale, and coal (Keefer 1972). In southern Wyoming, along the Rawlins uplift, the Mesaverde Group includes the , the Pine Ridge Sandstone, the Allen Ridge Formation, and the Haystack Mountains Formation (Erathem-Vanir 2012). Fossils found in the Mesaverde Group include plants, nonmarine snails and bivalves, reptiles, fish, , and tracksites (Keefer 1972, Murphey and Daitch 2007, Lockley et al. 2011). A previous search for known fossil localities in the study area revealed one locality in the Mesaverde Group that included shark teeth, a bird, turtle shell fragments, teeth, and dinosaur teeth (Erathem-Vanir 2012). 4.11 Lance Formation (PFYC 5) The Lance Formation is composed of interbedded tan and gray sandstone and siltstone, gray shale, dark- gray and dark-brown carbonaceous shale, and coal. Freshwater and brackish-water mollusks, trace fossils, , amphibians, a crocodile, birds, and a dinosaur have been found in the Lance Formation (Gilmore 1931, Estes 1969, Estes and Sanchiz 1982, Roehler 1993, Elzanowski et al. 2000, Falkingham et al. 2010).

Riley Ridge to Natrona Project 6 November 2018 Paleontological Resources Technical Report

4.12 (PFYC 5) The Lewis Shale consists of dark-gray shale and some thin interbedded ledge-forming tan or brown very fine to fine-grained sandstone and siltstone. At times the Lewis Shale interfingers with the overlying Fox Hills Sandstone. Fossils found in the Lewis Shale include trace fossils, mollusks, ammonites, and dinosaur (Roehler 1993, Lucas et al. 2005). 4.13 Cody Shale (PFYC 3) The late Cody Shale consists of dark- to light-gray shale (marine) interlayered with thin gray to light-brown hard and soft sandstone and siltstone, and some calcareous concretionary beds that were laid down (Soister 1967, Finn 2014). There are 14 members recognized in the Cody shale that vary geographically (Erathem-Vanir 2012). Fossils found in the Cody Shale include mollusks, ammonites, shrimp, shark teeth, and fish (Cobban 1952, Merewether et al. 2010, Erathem-Vanir 2012). 4.14 Mowry and Thermopolis Shales (PFYC 3) The Cretaceous is a dark siliceous shale deposited in a restricted, oxygen-depleted sea referred to as the Mowry Sea. Fossil fish, shark, and rays have been found in the Mowry Shale (Reeside and Cobban 1960, Stewart and Hakel 2006, Erathem-Vanir 2012). The consists of black shale, the basal member of which contains tan and rusty- interbedded and sandstones. Fossils include plants, bacculites, and foraminifera and crocodile, fish, and bivalves (Eicher 1960, Erathem-Vanir 2012). 4.15 Cloverly, Morrison, and Sundance Formations (PFYC 5) The consists of conglomerate, , and mudstone. Fossils found in the Cloverly Formation include dinosaurs, , lizards, and fish (Erathem-Vanir 2012). The consists of fluvial and lacustrine deposits characterized by thick layers of multicolored mudstone in the Rocky Mountain Region. Facies changes are found throughout the initial sequence of the formation due to discontinuous sediments of heterolithic sandstone, siltstone, and mudstone (Ikejiri et al. 2006). Fossils found in the Morrison include dinosaurs, fish, amphibians, reptiles, trackways, and plants (Foster 2003, Ikejiri et al. 2006). The consists of an alternating sequence of greenish-gray shale, light-gray to yellowish-brown sandstone and siltstone, and gray limestone. A previous search for known fossil localities in the study area revealed one locality in the Sundance Formation that produced fragmentary post cranial bones (Erathem-Vanir 2012) 4.16 Frontier Formation (PFYC 3) The Frontier Formation is composed of shale, siltstone, sandstone, conglomerate, and deposited in marine and nonmarine environments (Dutton 1993, Merewether et al. 2010). Fossils found in the Frontier Formation include plants, ammonites, mollusks, and bivalves (Knowlton 1917, Merewether and Cobban 2007, and Merewether et al. 2010). 4.17 Chugwater and Dinwoody Formations (PFYC 3) The consists of interbedded red shales and siltstones and overlies the Dinwoody Formation. The Dinwoody Formation consists of brown, yellow, and green shales and interbedded gypsiferous siltstone, dolomite, and limestone (Bullock and Wilson 1969). Fossils found in the Chugwater Formation include plants, amphibians, and dinosaur tracks (Berry 1924, Katz 1976, Lovelace and Lovelace 2012). The Dinwoody Formation consists of brown, thin-bedded, marine siltstone

Riley Ridge to Natrona Project 7 November 2018 Paleontological Resources Technical Report

(Santucci and Wall 1998). Fossils fond in the Dinwoody Formation include brachiopods and conodonts (Santucci and Wall 1998, Rodland and Bottjer 2001). 4.18 Segment 1: Riley Ridge Treatment Plant to the Proposed Riley Ridge Sweetening Plant Segment 1 crosses 9 geologic units, 5 of which have very high potential (PFYC 5) to produce paleontological resources. These are the Laney Shale Member of the Green River Formation (Tgl), New York Tongue of the Wasatch Formation and Fontenelle Tongue of the Green River (Twg), Green River and Wasatch Formations (Tgrw), the La Barge and Chappo Members of the Wasatch Formation (Twlc), and the Wasatch Formation (Twd). The Proposed Action and Alternatives 1B: Dry Piney and 1C: Figure Four cross the same five geological units with PFYC 5. The geologic units and their PFYC are shown in Table 4-1.

Several members of the Green River and Wasatch formation are present in Segment 1. Both formations have a long history of producing scientifically significant fossils (Cope 1884, Mook 1959, Lundberg and Case 1978, West and Dawson 1975, Langston and Rose 1978, Savage and Waters 1978, Gingerich and Dorr 1979, Dorr and Gingerich 1980, Grande 1984, Honey et al. 1988, Gunnell 1994, Gunnell and Bartels 1994, Ferber and Wells 1995, Gardner 1999, Zonneveld et al. 2000, Foster 2001, McGee 2002, Murphey and Daitch 2007. A previous paleontological resource assessment found fossil turtle and crocodile remains along this segment (Erathem-Vanir 2012).

Table 4-1 Geological Units and Associated Potential Fossil Yield Classification in the Study Area Age Geologic Unit Symbol PFYC Segment 1: Riley Ridge Treatment Plant to the Proposed Riley Ridge Sweetening Plant /Holocene Alluvium and Colluvium Qa 1 to 2 Pleistocene/Holocene Gravel, Pediment, and Fan Deposits Qt 1 to 2 Eocene Laney Shale Member of Green River Formation Tgl 5 New York Tongue of the Wasatch Formation and Fontenelle Eocene Twg 5 Tongue of the Green River Eocene Green River and Wasatch Formations Tgrw 5 Eocene La Barge and Chappo Members of the Wasatch Formation Twlc 5 Eocene Diamictite and Sandstone of Wasatch Formation Twd 5 - Darby Formation MD 2 - Middle Cambrian-Upper Ordovician Limestone and Dolomite O_ 2 Segment 2: Proposed Riley Ridge Sweetening Plant to the Bairoil Interconnect Pleistocene/Holocene Alluvium and Colluvium Qa 1 to 2 Pleistocene/Holocene Sand and Loess Qs 1 to 2 Pleistocene/Holocene Playa Lake and Other Lacustrine Deposits Ql 1 to 2 Pleistocene/Holocene Alkalic Volcanic Rock Qi 1 Pleistocene/Holocene Gravel, Pediment and Fan Deposits Qt 1 Miocene Browns Park Formation/Miocene Rocks Tm 3 Oligocene White River Group Twr 5 Eocene Laney Shale Member of Green River Formation Tgl 5 Eocene Fontenelle Tongue of Green River Formation Twg 5 Eocene Tipton Shale Member or Tongue of Green River Formation Tgt 5 Eocene Wilkins Peak Member of Green River Formation Tgw 5 Wilkins Peak Member and Tipton Shale Member or Tongue of Eocene Tgwt 5 Green River Formation Eocene Cathedral Bluffs Tongue of Wasatch Formation Twc 5

Riley Ridge to Natrona Project 8 November 2018 Paleontological Resources Technical Report

Table 4-1 Geological Units and Associated Potential Fossil Yield Classification in the Study Area Age Geologic Unit Symbol PFYC Eocene Bridger Formation Tb 5 Eocene Crooks Gap Conglomerate Tcg 3 Transition Between Battle Spring Formation and Wasatch Eocene Tbw 3 Formation Paleocene/Eocene Battle Spring Formation Tbs 3 Paleocene/Eocene Main Body of Wasatch Formation Twm 5 Paleocene Fort Union Formation Tfu 3 Cretaceous Almond Formation of Mesaverde Group Kal 3 Segment 3: Bairoil Interconnect to the Lost Cabin/Natrona Hub Interconnect Pleistocene/Holocene Alluvium and Colluvium Qa 1 to 2 Pleistocene/Holocene Dune Sand and Loess Qs 1 to 2 Miocene Miocene Rocks Tm 3 Oligocene White River Formation Twr 5 Eocene Wind River Formation Twdr 5 Paleocene/Eocene Battle Spring Formation Tbs 3 Paleocene Fort Union Formation Tfu 3 Cretaceous Lance Formation Kl 5 Lance Formation, Fox Hills Sandstone, Meeteetse Formation, Cretaceous Klm 5 Bearpaw and Lewis Shales Cretaceous Frontier Formation Kf 3 Cretaceous Meeteetse Formation and Lewis Shale Kml 3 Cretaceous Mesaverde Formation or Group Kmv 3 Cretaceous Cody Shale Kc 3 Cretaceous Mowry and Thermopolis Shales Kmt 3 Jurassic/Cretaceous Cloverly, Morrison, and Sundance Formations KJs 5 Triassic Chugwater and Dinwoody Formations @cd 3 Granitic Rocks Wg 1 Proterozoic Metasedimentary and Metavolcanic Rocks WVsv 1 4.19 Segment 2: Proposed Riley Ridge Sweetening Plant to the Bairoil Interconnect Segment 2 crosses 23 geologic units, 18 of which have moderate to very high potential to produce paleontological resources. These include the Almond Formation and Mesaverde Group (Kal), (Kfl), Landslide Creek Formation (Kl), Lewis Shale (Kle), Bridger Formation (Tb), Battle Springs Formation (Tbs), Transition between Battle Springs Formation and Wasatch Formation (Tbw), Crooks Gap Conglomerate (Tcg), Fort Union Formation (Tfu), Green River Formation (Tgl, Tgt, Tgw, and Tgwt), New York Tongue of the Wasatch Formation and Fontenelle Tongue of the Green River (Twg), Browns Park Formation (Tm), Wasatch Formation (Twc, Twm), and White River Group (Twr). A previous paleontological resource assessment found fossil crocodile and remains along this segment (Erathem-Vanir 2012). In addition, an old GLO map shows and area labeled as having “petrified forest with fossil reptilian remains” that would be crossed by the Project southeast of Highway 28. 4.20 Segment 3: Bairoil Interconnect to the Lost Cabin/Natrona Hub Interconnect Segment 3 crosses 25 geologic units, 19 of which have moderate to very high potential to produce paleontological resources. These include the Chugwater Group (@cd), Cody Shale (Kc), Frontier

Riley Ridge to Natrona Project 9 November 2018 Paleontological Resources Technical Report

Formation (Kf), Sundance Formation (KJs), Landslide Creek Formation (Kl), Lance Formation/Fox Hills Sandstone/Meeteetse Formation/ Bearpaw and Lewis Shales (Klm), Meeteetse Formation (Kml), Mowry Shale and Thermopolis Shale (Kmt), Mesaverde Group (Kmv), Cloverly Formation (MzPz), Minnekahta Limestone (PM), Battle Spring Formation (Tbs), Crooks Gap Conglomerate (Tcg), Fort Union Formation (Tfu), Browns Park Formation (Tm), Wagon Bed Formation (Twwb), Wind River Formation (Twdr), and White River Group (Twr). A previous paleontological resource assessment found fossil turtle and petrified wood along this segment, south of Highway 26 (Erathem-Vanir 2012).

Riley Ridge to Natrona Project 10 November 2018 Paleontological Resources Technical Report

5.0 Literature Cited Berry, E.W. 1942 1924. Fossil plants and unios in the of Wyoming. The Journal of Geology 32:488-497 Brown R.W. 1958 Fort Union Formation in the , Wyoming. Wyoming Geological Association 13th Annual Field Conference Guidebook. Bullock, J.M., and W.H. Wilson 1969 Gypsum deposits in the Cody Area, Park County, Wyoming. The Geological Survey of Wyoming, Preliminary Report Number 9, 12 pages. Cobban, W.A. 1952 A new upper Cretaceous ammonite genus from Wyoming and Utah. Journal of 26(5):758-760. Cope, E.D 1884 Vertebrata of the Tertiary Formations of the west. Report of the U.S. Geological Survey of the Territories, vol. 3. Dutton , S.P. 1993 Influence of provenance and burial history on diagenesis of lower Cretaceous Frontier Formation sandstones, Green River basin, Wyoming. Journal of Sedimentary Petrology 63(4):665-677. Eicher, D.L. 1960 Stratigraphy and micropaleontology of the Thermopolis Shale. Peabody Museum of Natural History Bulletin 15, 126 pages and 6 plates. Elzanowski, A., G.S. Paul, and T.A. Stidham 2000 An avian quadrate from the late Cretaceous Lance Formation of Wyoming. Journal of Vertebrate Paleontology 20(4):712-719. Emry, R.J. 1975 Revised Tertiary stratigraphy and paleontology of the Western Beaver Divide, Fremont County, Wyoming. Smithsonian Contributions to Paleobiology, Number 26. Emry, R.J. and W.W. Korth 2012 Early (late Eocene) rodents from the Flagstaff Rim Area, central Wyoming. Journal of Vertebrate Paleontology 32(2):419-432. Erathem-Vanir Geological Consultants 2012 Paleontological Resources Assessment Report (EVG-2012WY-232). Prepared for Denbury Onshore LLC, Plano, by Erathem-Vanir Geological Consultants, Pocatello, , 157 p. Estes, R. 1969 Relationships of two Cretaceous lizards (Sauria, ). Brevoria, Number 317. Estes, R. and B. Sanchiz 1982 New discoglossid and palaeobatrachid from the late Cretaceous of Wyoming and , and a review of other frogs from the Lance and Hell Creek formations. Journal of Vertebrate Paleontology 2(1):9-20.

Riley Ridge to Natrona Project 11 November 2018 Paleontological Resources Technical Report

Falkingham, P.L., J. Milan, and P.L. Manning 2010 A crocodilian trace from the Lance Formation (upper Cretaceous) of Wyoming. Pp. 171- 174 In Milan, J., S.G. Lucas, M.G. Lockley, and J.A. Spielmann (Eds.) Crocodyle tracks and traces. Museum of Natural History and Science Bulletin 51. Ferber, C.T. and N.A. Wells. 1995 Paleolimnology and taphonmy of some fish deposits in “Fossil” and “Uinta” Lakes of the Eocene Green River Formation, Utah and Wyoming. Palaeogeography, Palaeoclimatology, Palaeoecology 117 (3-4):185-210. Finn, T.M 2014 Lower Cody Shale (Niobrara equivalent) in the , Wyoming and Montana– Thickness, distribution, and source rock potential. U.S. Geological Survey Scientific Investigations Report 2013-5138, 32 pages. Foster, J.R. 2001 tracks (Ambystomichnus?) from the Cathedral Bluffs Tongue of the Wasatch Formation (Eocene), southwestern Wyoming. Geological Society of America, Rocky Mountain Section, 52nd Annual Meeting, Missoula, MT, , April 17-18, 2000, 32(5)8-9. 2003 Paleoecological analysis of the vertebrate fauna of the Morrison Formation (upper Jurassic), Rocky Mountain Region, U.S.A. New Mexico Museum of natural History and Science Bulletin 23, 95 pages. Gardner, J.D. 1999 Comments on amphibians from the Green River Formation with a description of a fossil tadpole. Vertebrate paleontology in Utah. Miscellaneous Publication, Utah Geological Survey 99-1:455-461. Gilmore, C.W. 1931 A new species of Troodont dinosaur from the Lance Formation of Wyoming. Proceedings U.S. National Museum 79(9):6 pages, 5 plates. Gingerich, P.D. and J.A. Dorr, Jr. 1979 Mandible of Chiromyoides minor (Mammalia, Primates) from the upper Paleocene Chappo Member of the Wasatch Formation, Wyoming. Journal of Paleontology 53(3):550-552. Dorr, J.A. and P.D. Gingerich. 1980. Early Cenozoic mammalian paleontology, geologic structure, and tectonic history in the overthrust belt near LaBarge, Wyoming. University of Wyoming Contributions to Geology 18:101-115. Grande, L. 1984 Paleontology of the Green River Formation, with a review of the fish fauna; second edition. Bulletin-Geological Survey of Wyoming 63:333. Gunnell, G.F. 1994 Paleocene mammals and faunal analysis of the Chappo type locality (Tiffanian), Green River Basin, Wyoming. Journal of Vertebrate Paleontology 14(1):81-104. Gunnell, G.F. and W.S. Bartels. 1994 Early Bridgerian (middle Eocene) vertebrate paleontology and palaeoecology of the southern Green River Basin, Wyoming. Contributions to Geology, University of Wyoming 30(1):57-70.

Riley Ridge to Natrona Project 12 November 2018 Paleontological Resources Technical Report

Honey, J.G. and G.A. Izett 1988 Paleontology, taphonomy, and stratigraphy of the Browns Park Formation (Oligocene and Miocene) near Maybell, Moffat County, Colorado. U.S.G.S. Professional Paper 1358, 52 pages. Honey, J.G., H.W. Roehler, J.H. Hanley, and J.G. Honey 1988 A mammalian fauna from the base of the Eocene Cathedral Bluffs Tongue of the Wasatch Formation, Cottonwood Creek Area, southeast Washakie Basin, Wyoming. In Geology and palaeoecology of the Cottonwood Creek delta in the Eocene Tipton Tongue of the Green River Formation and a mammalian fauna from the Eocene Cathedral Bluffs Tongue of the Wasatch Formation, southeast Wahsakie Basin, Wyoming. U.S.G. Bulletin B 1669 A-C, p. C1-C14. Ikejiri, T., P.S. Watkins, and D.J. Gray 2006 Stratigraphy, sedimentology, and taphonomy of a sauropod quarry from the upper Morrison Formation of Thermopolis, central Wyoming. Pp. 39-46 In Foster, J.R. and S.G. (Eds.) Paleontology and geology of the upper Jurassic Morrison Formation. New Mexico Museum of Natural history and Science Bulletin 36. Johnson, K.R. 1986 Paleocene bird and amphibian tracks from the Fort Union Formation, Bighorn Basin, Wyoming. Contributions to Geology, University of Wyoming 24(1):1-10. Katz, S.G. 1976 Restoration of the vertebrate fossil collection of the University of Missouri at Columbia. Journal of Paleontology 50(1):194-197. Keefer, W.R. 1970 Structural geology of the Wind River Basin, Wyoming. U.S. Geological Survey Professional Paper 495-D, 35 pages. 1972 Frontier, Cody, and Mesaverde Formations in the Wind River and Southern Bighorn Basin, Wyoming. U.S.G. Professional Paper 495-E. Kihm, A.J. 1987 Mammalian paleontology and geology of the Yoder Member, , east- central Wyoming. Dakoterra 3:25-45. Knowlton, F.H. 1917 A fossil flora from the Frontier Formation of southwestern Wyoming. U.S. Geological Survey Professional paper 108-F, 94 pages and 39 plates. Langston, E., Jr., and H. Rose 1978 A yearling crocodilian from the middle Eocene Green River Formation of Colorado. Journal of Paleontology 52(1):122-125. Lockley, M., K. Cart, J. Martin, and A.R.C. Milner 2011 New theropod tracksites from the upper Cretaceous “Mesaverde” Goroup, western Colorado: Implications for Ornithomimosaur track morphology. New Mexico Museum of Natural History and Science Bulletin 53:321-329. Love, J.D. 1970 Cenozoic geology of the Granite Mountains area, central Wyoming. U.S. Geological Survey Professional Paper 495-C, 154 pages.

Riley Ridge to Natrona Project 13 November 2018 Paleontological Resources Technical Report

Lovelace, D.M., and S.D. Lovelace 2012 Paleoenvironments and paleoecology of a lower Triassic invertebrate and vertebrate Ichnoassemblage from the Red Peak Formation (Chugwater Group), central Wyoming. Palaios 27(9):636-657. Lucas, S.G., T. Ikejiri, H. Maisch, T. Joyce, and G.L. Gianniny 2005 The mosasaur Prognathodon from the upper Cretaceous Lewis Shale near Durango, Colorado and the distribution of Prognathodon in . New Mexico Geological Society, 56th Field conference, Geology of Chama Basin, pages 389-394. Lundberg, J.G., and G.R. Case 1970 A new catfish from the Eocene Green River Formation, Wyoming. Journal of Paleontology 44(3):451-457. McGee, E.M. 2002 Intraspecific dental variability in cf. Coryphodon anthracoidens (Mammalia, Pantodonta) from Roehler’s Coryphodon Catastrophe Quarry, Washakie Basin, Wyoming. Rocky Mountain Geology 37(1):61-73. Merewether, E.A. and W.A. Cobban 2007 Outcrop descriptions and fossils from the upper Cretaceous Frontier Formation, Wind River Basin and adjacent areas, Wyoming. In Wind river Basin Province Assessment Team, Petroleum Sustems and Geologica Assessment of oil and gas in Wind River basin Province, Wyoming. U.S. Geological Survey Digital Data Series DDS-69-J, chapter 11, 95 pages. Merewether, E.A., W.A. Cobban, and R.W. Tillman 2010 Outcrops, fossils, geophysical logs, and tectonic interpretations of the upper Cretaceous Frontier Formation and contiguous strata in the Bighorn Basin, Wyoming and Montana. U.S. Geological Survey Scientific Investigations Report 2009-5256, 49 pages. Mook, C.C. 1959 A new species of fossil crocodile of the genus Leidyosuchus from the Green River Beds [Wyoming]. American Museum Novitates 1933:6. Murphey, P.C. and D. Daitch 2007 Paleontological Overview of Oil Shale and Tar Sands Areas in Colorado, Utah, and Wyoming. Report prepared for the U.S. Department of the Interior, Bureau of Land Management. Murphey, P.C. and E. Evanoff 2011 Paleontology and stratigraphy of the middle Eocene Bridger Formation, southern Green River Basin, Wyoming. Proceedings of the 9th Conference on Fossil Resources, pages 83- 109. Reeside, J.B. and W.A. Cobban 1960 Studies of the Mowry Shale (Cretaceous) and contemporary formations in the United States and Canada. U.S. Geological survey Professional paper 355, 126 pages and 58 plates. Robinson, P. 1966 Fossil Mammalia of the Huerfano Formation, Eocene, of Colorado. Peabody Museum of Natural History Bulletin 21, 95 pages. Rodland, D.L. and D.J. Bottjer 2001 Biotic recovery from the end- mass extinction: Behavior of the inarticulate brachiopod Lingula as a disaster taxon. Palaios 16(1):95-101.

Riley Ridge to Natrona Project 14 November 2018 Paleontological Resources Technical Report

Roehler, H.W. 1992 Description and correlation of Eocene rocks in stratigraphic reference sections for the Green River and Washakie Basins, southwestern Wyoming. U.S. Geological Survey Professional Paper 1506-D, 83 pages. 1993 Stratigraphy of the upper Cretaceous Fox Hills Sandstone and adjacent parts of the Lewis Shale and Lance Formation, east flank of the Rocks Springs Uplift, southwest Wyoming. U.S. Geological Survey, Professional Paper 1532, 57 pages. Rowley, P.D., W.R. Hanson, O. Tweto, and P.E. Carrara 1985 Geology map of the Vernal degree 1 x 2 degree quadrangle, Colorado, Utah, and Wyoming. U.S. Geological Survey Miscellaneous Investigations Series Map I-526. Santucci, V.L. and W.P. Wall 1998 Paleontological resources at Grand Teton National Park, northwestern Wyoming. University of Wyoming National Park Service Research Center Annual Report Volume 22, Article 7:31-36. Savage, D.E., and B.T. Waters 1978 A new omomyid from the Wasatch Formation of southern Wyoming. Folia Primatologica 30(1):1-29. Schmitt, L.J., Jr. 1979 Geologic map of the Crooks Peak Quadrangle, Fremont and Sweetwater counties, Wyoming. U.S. Geological Survey Geologic Quadrangle Map, GQ-1517, scale 1:24,000. Soister, P.E. 1968 Stratigraphy of the Wind River Formation in south-central Wind River Basin, Wyoming. U.S. Geological Survey Professional Paper 594-A, 50 pages. Soister, P.W. 1967 Geology of the Puddle Sprngs Quadrangle Fremont County, Wyoming. U.S. Geological Survey Bulletin 1242-C, 36 pages. Stephens, J.G. 1964 Geology and uranium deposits at Crooks Gap, Fremont County, Wyoming. U.S. Geological Survey Bulletin 1147-F, 82 pages. Stewart, J.D. and M. Hakel 2006 Ichthyofauna of the Mowry Shale (early ) of Wyoming. Pp. 161-163 In Lucas, S.G. and R.M. Sullivan (Eds.) Late Cretaceous from the Western Interior. New Mexico Museum of Natural History and Science Bulletin 35. Sullivan, R.M. 1982 Fossil lizards from Swain Quarry: Fort Union Formation,” middle Paleocene (Torrejonian), Carbon County, Wyoming. Journal of Paleontology 56(4):996-1010. Surovell, Todd, and P. Jeffrey Brantingham 2007 A Note on the Use of Temporal Frequency Distributions in Studies of Prehistoric Demography. Journal of Archaeological Science 34:1868–1877. SWCA Environmental Consultants (SWCA) 2014 Resource Report 6 Geology. March 2014. West, R.M. and M.R. Dawson. 1975 Eocene fossil Mammalia from the Sand Wash Basin, northwestern Moffat County, Colorado. Annals of Carnegie Museum 45 (Article 11): 231-253.

Riley Ridge to Natrona Project 15 November 2018 Paleontological Resources Technical Report

Williamson, T. E., S.G. Lucas, and R.K. Stucky 1996 Megalesthonyx hopsoni (Mammalia: tillodonta) from the early Bridgerian (Gardnerbuttean) of the Wind River Formation, northeastern Wind River Basin, Wyoming. Proceedings of the Denver Museum of natural History Series 3, Number 12, 3 pages. Zanazzi, A. and M.J. Kohn. 2008 Ecology and physiology of White River mammals based on stable isotope ratios of teeth. Palaeo 257:22-37. Zonneveld, J.P., G.F. Gunnell, and W.S. bartels. 2000 Early Eocene fossil vertebrates from the southwestern Green River Basin, Lincoln and uinta counties, Wyoming. Journal of Vertebrate Paleontology 20(2):369-386.

Riley Ridge to Natrona Project 16 November 2018 Paleontological Resources Technical Report