rare earth elements in Wyoming

Deacon’s Prayer Group Claims . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
Phosphate-Rich Sedimentary Occurrences . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Uraniferous Phosphatic Horizons in the Wilkins Peak Member of the
Green River Formation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Phosphorite Beds in Western Wyoming. . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Dahllite Concretions in the Thermopolis Shale, Big Horn County . . . . . . .62
Occurrences of Other Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Figures
Figure 1. Sample locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 2. Sample of FMR dike at Bear Lodge REE project. . . . . . . . . . . . . . . . . . . 18
Figure 3. Map of Bear Lodge REE project. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Figure 4. Locations of Precambrian samples. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 5. Tie Siding area geology and samples. . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 6. Tie Siding pegmatites. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Figure 7. Allanite from the Holiday Place pegmatite. . . . . . . . . . . . . . . . . . . . . . . 27
Figure 8. Big Creek area geology and samples. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Figure 9. Samples of the Big Creek - Platt pegmatites. . . . . . . . . . . . . . . . . . . . . . . 31
Figure 10. Union Pass-Warm Spring area geology and samples. . . . . . . . . . . . . . . . 35
Figure 11. Wildcat Road, iron-rich pod- quartz monzonite contact. . . . . . . . . . . . . 36
Figure 12. Photomicrograph of zircon grain within biotite. . . . . . . . . . . . . . . . . . . 36
Figure 13. Locations of paleoplacer, placer, and other sandstone-hosted samples . . 40
Figure 14. Conglomerate of the lower Flathead Sandstone. . . . . . . . . . . . . . . . . . . 41
Figure 15. Bald Mountain area geology and samples. . . . . . . . . . . . . . . . . . . . . . . 43
Figure 16. Gold flake and monazite grains. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Figure 17. Mesaverde Formation titaniferous black sandstone outcrops. . . . . . . . . 48
Figure 18. Cottonwood Creek Mesaverde Formation heavy sand. . . . . . . . . . . . . . 50
Figure 19. Spring Gap Frontier Formation outcrop and samples . . . . . . . . . . . . . . 52
Figure 20. Spring Gap area geology and samples. . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Figure 21. Locations of phosphate-related samples. . . . . . . . . . . . . . . . . . . . . . . . . 56
Figure 22. South Firehole Canyon lithostratigraphy and samples. . . . . . . . . . . . . . 59
Figure 23. South Firehole Canyon UPZ 2a within Wilkins Peak Member. . . . . . . . 60
Figure 24. Phosphoria Formation outcrop near Hoback. . . . . . . . . . . . . . . . . . . . . 61
Figure 25. Dahllite-bearing Thermopolis Shale. . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Figure 26. Dahllite concretions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Figure 27. WSGS geologist Bob Gregory collecting a REE sample. . . . . . . . . . . . . 66
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