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Volume of a Potential Lake in the Colorado Plateau Basin
Get PDFThe southernmost area of the Colorado Plateau, known as the “Bidahochi Basin,” is a structural depression over much of the Little Colorado River. The basin is primarily bounded by the Mogollon Rim and the Kaibab Uplift and is filled with Miocene-Pliocene sedimentary strata that reflect a lacustrine environment, most notably preserved in the diatremes and maars of the Hopi Buttes. Initially interpreted as remnants of smaller playa-like lakes (~7000 km³), recent discoveries of tufa deposits and shoreline terraces at 1800-2000 m elevations suggest a larger lake. Others have estimated this “Hopi Lake” to have volumes up to 30,000 km³ (Dallegge et al. 2003). Due to its size and proximity to the Grand Canyon, others have hypothesized that this large lake contributed to the carving of the Grand Canyon by catastrophically overflowing the Kaibab Uplift (Austin et al. 2023; Douglass and Gootee 2024). Alternative theories have also been suggested, such as karst piracy (Hill and Polyak 2014) or serial lake spillover models. Given these interpretations, creating a comprehensive map to better analyze the basin is essential.
The basin was initially outlined in Google Earth Pro using the polygon tool at the 1860 m contour, providing a rough surface area estimate. All subsequent analyses were performed in ArcGIS Pro. Raster data for the Colorado Plateau was acquired from USGS EarthExplorer and merged into a mosaic. A fitted polygon, created in Google Earth Pro and imported into ArcGIS, was used to trim the raster. This trimmed raster generated 20m elevation contours for the basin. Six key elevations—1600, 1800, 1860, 1950, 2000, and 2100 meters—were selected based on prior research and converted into polygons. Volume calculations for each elevation were made using ArcGIS’s “Surface Volume (3D)” tool. Notable features and Mogollon Rim/Kaibab Uplift gaps were recorded, and relevant geologic map units were included to highlight the basin’s volcanic and lake deposits.
Hopi Lake extended much further north than previously thought, reaching from the Grand Canyon’s mouth up to Moab, Utah, at each studied elevation. At elevations above the 1800 m contour, it reached the Uinta Mountains. Additional “basins” appeared in Glen Canyon, Monument Valley, and areas west of Canyonlands National Park. A lake “outlet” also opened north of the Vermillion Cliffs across the Cockscomb (Kaibab Uplift, Utah). At the 1860 m contour, a “shoreline” lies along the Hopi Buttes, and above the 2000 m contour, another outlet occurs north of the San Francisco volcanic field. Volumes for each elevation are shown in Table 1.
Our analysis suggests Hopi Lake extended farther north, possibly suggesting a serial lake spillover model. With a volume of ~40,000 km³, it could have catastrophically carved the Grand Canyon, similar to how Lake Missoula (~2600 km3) or Lake Bonneville (~10,000 km³) shaped their respective drainages (Smith 2006; O’Connor et al. 2020). Based on its current elevation, the Hopi Buttes volcanic event may also have contributed to Hopi Lake’s overspill, possibly uplifting and displacing enough water to overtop the Kaibab Uplift. Field investigations at proposed outlets or shorelines could further clarify the lake’s true extent and geologic history.
References:
Austin S.A., E.W. Holroyd III, T.F. Folks, and N. Loper. 2023. Shoreline transgressive terraces: Tufa-encrusted landforms indicate rapid filling and failure of Hopi Lake, western Bidahochi Basin, northeastern Arizona. In J.H. Whitmore (editor), Proceedings of the Ninth International Conference on Creationism, pp. 346-362. Cedarville, Ohio: Cedarville University International Conference on Creationism
Dallagge T.A., M.H. Ort, W.C. McIntosh. 2003. Mio-Pliocene Chronostratigraphy, Basin Morphology and Paleodrainage Relations Derived From The Bidahochi Formation, Hopi and Navajo Nations, Northeastern Arizona: The Mountain Geologist 40, no. 5:55-82.
Douglass J., and B.F. Gootee. 2024. Discovery of beach sand, beachrock, and capping tufa on Balakai Mesa: Implications for the Bidahochi Formation and the overflow origin of the Grand Canyon: Open-File Report 24-02, 9 p. University of Arizona: Arizona Geological Survey.
Hill C. A., and V. J. Polyak. 2014. Karst Piracy: A Mechanism for Integrating the Colorado River across the Kaibab Uplift, Grand Canyon, Arizona, USA. Geosphere 10, no. 4:627–40. DOI: 10.1130/GES00940.1
O’Connor J.E., V.R. Baker, R.B. Waitt, L.N. Smith, C.M. Cannon, D.L. George, R.P. Denlinger. 2020. The Missoula and Bonneville floods—A review of ice-age megafloods in the Columbia River basin: Earth-Science Reviews 208, pp. 1-51. DOI: 10.1016/j.earscirev.2020.103181
Smith L.N. 2006. Stratigraphic evidence for multiple drainings of glacial Lake Missoula along the Clark Fork River, Montana, USA. Quaternary Research, no. 66:311-322. DOI: 10.1016/j.yqres.2006.05.009
Appendix:
Table 1
Volume data of each contour with Lake Bonneville included.
Elevation/Location
Volume (km3)
C Plateau- 1600 m
10,649
C Plateau- 1800 m
33,656
C Plateau- 1860 m
44,178
C Plateau- 1950 m
62,429
C Plateau- 2000 m
74,393
C Plateau- 2100 m
101,816
Pluvial Lake Bonneville (O’Connor et al. 2020)
10,420
Glacial Lake Missoula (Smith 2006)
2,600
Caspian Sea
78,200
Lake Superior
12,10
“Christmas with a Covenanter”: Martha McMillan’s Yuletide Experience
Get PDFChristmas: whenever the modern American hears that word, the first thing that comes to mind is usually Santa Claus and his reindeer, or maybe the baby Jesus tucked into a manger on his neighbor\u27s front lawn. But it would surprise many Americans to learn that such traditions, even the very concept of this holiday, are relatively recent additions to the American mythos. This paper chronicles Martha McMillan\u27s encounter with the advent of this now-quintessential holiday to her native Ohio as recorded in her journal, and is supplemented by an additional array of contemporary sources offering their takes as well. Readers will uncover the truth about the origins of many traditions we now take for granted, as well as a store of tragically-lost trivia which shall doubtless leave them with a better understanding of their forebears\u27 habits when it came to merrymaking
Living in Community: Friendship and Hospitality in Martha McMillan’s 1889 Journal
Get PDFThis paper explores the stories of friendship from that characterized the life of Martha McMillan in 1889. The stories reveal the nature of hospitality and community in Cedarville, Ohio, in the 19th century. – Editor’s Summar
The Opera Party: An Inquiry into the Politics of Opera in England during the 17th and 18th Centuries
Get PDFBy investigating research from a number of sources, this paper seeks to provide evidence that opera can be used to communicate political opinions and that it, in fact, has been used to do so in the past. Operas from the late seventeenth and early eighteenth centuries in England are the main focus. After a brief explanation of the origins of opera and its arrival in England, the methods and motivations of composers who included political propaganda in their works are discussed. A summary of the political state of England is included to provide background for the dissection of Handel’s Arianna in Creta and Porpora’s Arianna in Nasso which are used to supply specific examples of politics’ role in opera. In light of the history of opera, the methods and intentions of composers, and the political status of Great Britain during the late seventeenth and early eighteenth centuries, the analysis of these two operas suggests their integration of political propaganda. The author concludes that not every opera is a vehicle for propaganda but that every opera should be carefully evaluated to determine if there is political intent
