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Joanna L. Redwine

Publications and source records attributed to Joanna L. Redwine.

5 recordsLinked to original sources
USGS2021

Middle and late Pleistocene pluvial history of Newark Valley, central Nevada, USA

Newark Valley lies between the two largest pluvial lake systems in the Great Basin, Lake Lahontan and Lake Bonneville. Soils and geomorphology, stratigraphic interpretations, radiocarbon ages, and amino acid racemization geochronology analyses were employed to interpret the relative and numerical ages of lacustrine deposits in the valley. The marine oxygen isotope stage (MIS) 2 beach barriers are characterized by well-preserved morphology and deposits with youthful soil development, with Bwk horizons and maximum stage I+ carbonate morphology. Radiocarbon ages of gastropods and tufas within these MIS 2–age deposits permit construction of a latest Pleistocene lake-level curve for Newark Valley, including a maximum limiting age of 13,780 ± 50 14 C yr B.P. for the most recent highstand, and they provide a calibration point for soil development in lacustrine deposits in the central Great Basin. The MIS 8–age to MIS 4–age beach barriers are higher in elevation and represent a larger lake than existed during MIS 2. The beach barriers have subdued morphology, are only preserved in short segments, and have stronger soil development, with Bkm and/or Bkmt horizons and maximum stage III+ to IV carbonate morphology. Newark Lake reached elevations higher than the MIS 2 highstand during at least two additional pluvial periods, MIS 16 and MIS 12, 10, or 8. These oldest lacustrine deposits do not have preserved shoreline features and are represented only by gravel lags, buried deposits, and buried soils with similar strong soil development. This sequence of middle and latest Pleistocene shorelines records a long-term pluvial history in this basin that remained internally drained for the last four or more pluvial cycles. Obtaining numerical ages from material within lacustrine deposits in the Great Basin can be challenging. Amino acid D/L values from gastropod shells and mollusk valves proved to be a valuable tool to correlate lacustrine deposits within Newark Valley. Comparison of soils and geomorphology results to independent 36 Cl cosmogenic nuclide ages from a different study indicated unexpected changes in rates of soil development during the past ~200,000 yr and suggested that common stratigraphic changes in lake stratigraphy could obscure incremental changes in soil development and/or complicate 36 Cl cosmogenic nuclide age estimates.

Nevada↗
USGS2014

Logs and data from trenches across the Berryessa Fault at the Jerd Creek site, northeastern Napa County, California, 2011-2012

The primary purpose of this report is to provide drafted field logs of exploratory trenches excavated across the Berryessa Fault section of the northern Green Valley Fault (Lienkaemper, 2012; Lienkaemper and others, 2013) in 2011 and 2012 that show evidence for at least one surface-rupturing earthquake in the past few centuries. The site location and site detail are shown on sheet 1. The trench logs are shown on sheets 1, 2, 3 and 4. We also provide radiocarbon ages used for chronological modeling of the earthquake history and a field description of a soil profile in one trench. A formal report based on these logs and data is in preparation.

California↗
USGS2008

Lake Manix shorelines and Afton Canyon terraces: Implications for incision of Afton Canyon

Lake Manix, in south-central California, was the terminal basin of the Mojave River until the late Pleistocene, when it drained east to the Lake Mojave Basin. Based on new field observations, radiocarbon ages, and soil development, we propose modifications to previously published hypotheses on the timing of the last 543 m above sea level (masl) highstand of Lake Manix, the timing of the first discharge eastward, and the time required to cut Afton Canyon between the two basins. Subtle beach barriers, wave-cut scarps, and lagged beach gravels indicate that Lake Manix reached highstands between 547 and 558 masl at least twice prior to its previously known 543 m highstands. Properties of soils formed on beach barriers at 547–549 masl compared to soils on dated deposits suggest an age of older than 35 cal ka for this highstand. Calibrated radiocarbon ages for three lacustrine highstands at or near 543 masl are ca. 40–35 ka, 33–30 ka, and 27–25 ka. Lake Manix periodically discharged down a drainage presently located on the north rim of Afton Canyon at 539 masl. Soil development estimated from multiple buried soils within fluvial deposits and overlying fan deposits suggests that discharge was coeval with or somewhat older than the 547–549 m highstand, and that fluvial aggradation in this drainageway was followed by a period of relative landscape stability and episodic burial by alluvial-fan deposits. Strath terraces below these highest fluvial deposits, but above the canyon rim, record initial incision of the Lake Manix threshold. Surface and soil properties indicate that they are latest Pleistocene to early Holocene in age, similar to the previously studied strath terraces that are inset well below the rim and below the basal lake sediments. We suggest that the higher straths above the rim formed no earlier than ca. 25 cal ka. We interpret the soils, stratigraphy, and fluvial landforms in the canyon to indicate relatively rapid incision of Afton Canyon to the depth of the bedrock floor of Lake Manix, followed by intermittent, gradual bedrock incision.

California↗
USGS2007

Quaternary stratigraphy, drainage-basin development, and geomorphology of the Lake Manix basin, Mojave Desert: Guidebook for fall field trip, Friends of the Pleistocene, Pacific Cell, October 4-7, 2007

The 2007 field trip of the Pacific Cell, Friends of the Pleistocene, visited features of the Quaternary geology and geomorphology of the Lake Manix basin in the Mojave Desert. This report is the guidebook for this trip and includes some discussion of relations observable along the road and at various field trip stops. The Mojave River originates in the San Bernardino Mountains and in high-water years flows north and east to its terminus in Silver Lake playa north of Baker, Calif. Along this course, the river passes through or near several basins that were internally drained prior to integration by the Mojave River, including the Victorville, Harper, Manix, and Soda Lake basins. Sediments in the Lake Manix basin record Mojave River discharge and lake fluctuations that began during the middle Pleistocene and continued through most of the late Pleistocene.

California↗