Article
OSL dating of two, perhaps three, pre-Bonneville deep-water pluvial lakes in Cache Valley, Utah-Idaho: Implications of their unexpected high altitudes for excavation of Cutler Narrows from a level above 1494 m (4901'), down to the present 1314 m (4310') mainly during the Bonneville lake cycle
Utah Geologic Survey
(2019)
Abstract
Pluvial-lake highstands in the Bonneville basin are known to be contemporaneous with periods of Quaternary glaciation. At
least five lake cycles have been identified from prior studies of two deep cores (Eardley and Gvosdetsky, 1960; Eardley and
others, 1973) and several isolated outcrops in the main part of the Bonneville basin and eastward in Cache Valley. These are the
Lava Creek B (~620 ka, marine isotope stage MIS 16), Pokes Point (~420 ka, MIS12), Little Valley (~150 ka, MIS 6), Cutler
Dam (~60 ka, MIS 4), and Bonneville (~18 ka, MIS 2) lake cycles (Oviatt and others, 1987, 1999; Lisiecki and Raymo, 2005).
Cache Valley, straddling the Utah-Idaho border, held the northeastern arm of Lake Bonneville, and is the entry point of the Bear
River, the largest river to supply water into the basin. This river did not fully enter the Bonneville basin until ~55 ka (Pederson
and others, 2016).
Pre-Bonneville pluvial lakes in Cache Valley rose to near or somewhat above the Provo shoreline several times, and deposited
stacked lacustrine gravel deposits exposed in an active Staker-Parson gravel pit on the southeast edge of Newton Hill (figures
1, 2). These deposits are separated either by multi-story, caliche- and clay-rich geosols, loess, erosional channels, or lag gravels.
The multi-story geosols formed in the post-Cutler Dam interglacial. These geosols are dated to MIS 3, and reflect first a
dry-condition Bk caliche soil, then deposition of loess and colluvium coincident with a period of more humid conditions. In
eastern Cache Valley, in southeast Hyde Park, Utah, similar multi-storied geosols and loess deposits underlie Bonneville offshore
silty sand with snails (west, lower) and post-Bonneville colluvial gravel (east, higher), respectively, where they overlie
Little Valley gravels at ~1493 m (4898 ft) and undated alluvial-fan deposits at ~1512 m (4960 ft).
We document stratigraphic evidence and absolute ages from optically stimulated luminescence (OSL) of quartz sand and infrared
stimulated luminescence (IRSL) of feldspar sand as evidence for at least two, perhaps three, pre-Bonneville lakes in Cache
Valley during past pluvial epochs: (1) ~137-169 ka (Little Valley; n=4); (2) ~96 ka (Newton Hill beds; n=1); and (3) ~49-67
ka (Cutler Dam; n=3) (tables 1, 2). These reached highstands, respectively, of >1470 m (>4824 ft; perhaps 4901 ft), >1443 m
(>4735 ft; perhaps 4768 ft), and ~1443 m (4733 ft). The Newton Hill beds might be the oldest lacustrine record of the Cutler
Dam lake cycle, if that lake cycle had a long duration, or they may be coeval with problematic lacustrine deposits of similar
ages, ~76 and 82 ka, in Hansel Valley (Robison and McCalpin, 1987) and ~90 ka in Gem Valley (Bouchard and others, 1998;
Utley, 2017).
Subsurface data from thousands of water wells drilled across the valley bottom southeast of Newton Hill document four,
perhaps five, successive deposits of deep-water muds with thin intervening gravels layers (Thomas and others, 2011; Oaks,
unpublished). These muds aggregate a total thickness between 30 m and 37 m (100 ft and 120 ft). These are probably coeval
with several of the nearshore gravel and sand deposits in the Newton Hill pit and with deposits of pluvial lakes in the main
Bonneville basin.
Synthesis of our new stratigraphic and geochronologic data show that all of the pre-Bonneville, post-Pokes Point pluvial lakes
rose to near or above the height of the Provo shoreline in the area of the Newton Hill gravel pit. Altitude control for older lakes
has been determined at only about 11 sites in the main part of the Bonneville basin, with some corrected for rebound, others...
See also https://works.bepress.com/susanne_janecke/232
https://works.bepress.com/susanne_janecke/233/
https://works.bepress.com/susanne_janecke/235/
Keywords
- lake Bonneville,
- Cutler Dam Lake Cycle,
- Little Valley lake cycle,
- OSL,
- dated lake beds,
- osl,
- Fielding paleosol
Disciplines
Publication Date
2019
Citation Information
Oaks, R.Q., Jr., Jänecke, S.U., Rittenour, T.M., Erickson, T.L., and Nelson, M.S., 2019, OSL dating of two, perhaps three, pre-Bonneville deep-water pluvial lakes in Cache Valley, Utah-Idaho: Implications of their unexpected high altitudes for excavation of Cutler Narrows from a level above 1494 m (4901'), down to the present 1314 m (4310') mainly during the Bonneville lake cycle. In W.R. Lund, A.P. McKean, and S.D. Bowman (Eds.), Proceedings Volume: 2018 Lake Bonneville Geologic Conference and Short Course. Day 1, Sessions 1-4; Utah Geological Survey. Miscellaneous Publication, MP-170-1. p. 90-153. https://ugspub.nr.utah.gov/publications/misc_pubs/mp-170/mp-170-1.pdf