Removal of the Northern Paleo-Teton Range along the Yellowstone Hotspot Track

Abstract

Classically held mechanisms for removing mountain topography (e.g., erosion and gravitational collapse) require 10-100 Myr or more to completely remove tectonically generated relief. Here, we propose that mountain ranges can be completely and rapidly (<2 Myr) removed by a migrating hotspot. In western North America, multiple mountain ranges, including the Teton Range, terminate at the boundary with the relatively low relief track of the Yellowstone hotspot. This abrupt transition leads to a previously untested hypothesis that preexisting mountainous topography along the track has been erased. We integrate thermochronologic data collected from the footwall of the Teton fault with flexural-kinematic modeling and length-displacement scaling to show that the paleo-Teton fault and associated Teton Range was much longer (min. original length 190-210 km) than the present topographic expression of the range front (~65 km) and extended across the modern-day Yellowstone hotspot track. These analyses also indicate that the majority of fault displacement (min. 11.4-12.6 km) and the associated footwall mountain range growth had accumulated prior to Yellowstone encroachment at ~2 Ma, leading us to interpret that eastward migration of the Yellowstone hotspot relative to stable North America led to removal of the paleo-Teton mountain topography via posteruptive collapse of the range following multiple supercaldera (VEI 8) eruptions from 2.0 Ma to 600 ka and/or an isostatic collapse response, similar to ranges north of the Snake River plain. While this extremely rapid removal of mountain ranges and adjoining basins is probably relatively infrequent in the geologic record, it has important implications for continental physiography and topography over very short time spans.

Constraining Displacement Magnitude on Crustal‐Scale Extensional Faults Using Thermochronology Combined With Flexural‐Kinematic and Thermal‐Kinematic Modeling: An Example From the Teton Fault, Wyoming, USA

“…Low temperature thermochronology has also been used in earlier attempts to constrain the cooling and uplift history of the Teton Range and displacement on the Teton fault (e.g., Brown et al, 2017;Roberts & Burbank, 1993;Thigpen et al, 2021). Low temperature thermochronometers such as apatite (U-Th)/He (AHe) and AFT record the time that rock particles passed through closure temperatures (T c ) zones of 80-40°C and 120-60°C, respectively, and therefore they can provide critical information about the thermal history of rock particles in active tectonic settings (Ehlers & Farley, 2003;Green et al, 1989;Ketcham et al, 1999Ketcham et al, , 2007Laslett et al, 1994;Rahn & Grasemann, 1999;Stüwe et al, 1994).…”

Effect of Dam Emplacement and Water Level Changes on Sublacustrine Geomorphology and Recent Sedimentation in Jackson Lake, Grand Teton National Park (Wyoming, United States)

“…Bathymetry, acoustic basement, and shallow acoustic facies data help to confirm inferences on the regional glacial and tectonic history made in previous investigations of Grand Teton National Park, as well as reveal novel aspects of the limnogeology of Jackson Lake (Figures 4, 5). The Teton fault imparts a first-order control on the availability of accommodation in the Jackson Hole basin (Byrd et al, 1994), and the deepwater depocenter of Jackson Lake approximately corresponds with the zone of maximum fault displacement identified by Thigpen et al (2021). The topography created by the Teton Range organizes both the regional hydrology and weather patterns, and therefore the interaction of rivers and storms with Jackson Lake (Byrd et al, 1994) (Figure 1).…”

“…Jackson Lake is the largest (~100 km 2 ) of several glacial lakes situated adjacent to the high-relief, seismically active Teton normal fault, a Miocene-aged structure that evolved with Basin and Range extension and Yellowstone hotspot activity (Brown et al, 2017;Thigpen et al, 2021) (Figures 2C,D). The Snake River flows into northern Jackson Lake and smaller underfit drainages enter along the basin's western transverse margin (Figure 1).…”

“…The topography created by the Teton Range organizes both the regional hydrology and weather patterns, and therefore the interaction of rivers and storms with Jackson Lake (Byrd et al, 1994) (Figure 1). That the major deepwater depocenter of Jackson Lake is situated adjacent to the Teton fault comes as little surprise, as fault-related subsidence considerably pre-dates Pleistocene glaciation and associated erosional scour (Licciardi and Pierce, 2018;Thigpen et al, 2021). Maximum water depth (~190 ms TWTT; ~143 m), maximum acoustic basement depth (~335 ms TWTT), and maximum sediment thickness (~150 ms TWTT) occur on the western side of the deepwater depocenter (Figure 4), and this feature defines both Jackson Lake's morphology and the spatial organization of acoustic facies.…”

Fossil Diatoms Reveal Natural and Anthropogenic History of Jackson Lake (Wyoming, USA)

“…The bedrock geology surrounding the lake ranges from Late Archean metamorphic to Late Quaternary sedimentary and volcanic rocks (Love et al, 1992;Smith et al, 1993). The Teton fault, a major N-S striking normal fault, produces the topography of the Teton Range and forms the western margin of Jackson Lake (Love and Reed, 1968;Byrd et al, 1994;Pierce and Haller, 2011;Zellman et al, 2019;Thigpen et al, 2021). Three major ice advances originating from the Greater Yellowstone Glacial System during the Late Pleistocene sculpted much of the topography present around Jackson Lake (Good and Pierce, 1996;Pierce et al, 2018).…”