A soils chronosequence at Terrace Creek; studies of late Quaternary tectonism in Dixie Valley, Nevada

Abstract

Fluvial and lacustrine landforms and their soils provide data that constrain the rates and times of late Quaternary tectonism at the Terrace Creek study site in Dixie Valley, Nevada. The most useful data for describing the terrace and fan chronosequence are stratigraphy, degree of surface dissection, desert-pavement development, and the Harden (1982) quantitative soil-development index. Two older terraces predate the 12,000 year old highstand shoreline of pluvial Lake Dixie, but two younger terraces and two correlative alluvial-fan surfaces postdate the shoreline. Each of the four terraces is truncated by piedmont faulting. At least one Holocene faulting event preceded the 1954 event; maximum Holocene displacement is about 2 m, including the 1954 event.

Rates of Soil Development from Four Soil Chronosequences in the Southern Great Basin

“…Techniques are needed to date surfaces reliably and correlate them to undated localities. Soils are potentially a useful correlation and dating tool because (1) soils develop on geomorphic surfaces at the onset of surface stabilization and (2) soil development increases systematically with increasing surface age, as demonstrated in arid/semiarid regions by several workers (Gile et al, 1966;Machette, 1985;Chadwick et al, 1984;McFadden, 1988;Holliday, 1988;Reheis, 1987a,b). The goals of this study are to characterize soil development in the south-ern Great Basin in locations with dated Quaternary surfaces, to estimate rates of soil development in such locations, and to evaluate the potential and the limitations of using soils to correlate and approximately date surfaces in the region.…”

Differential effects of base-level, tectonic setting and climatic change on Quaternary alluvial fans in the northern Great Basin, Nevada, USA

“…Climate appears to be the primary control over the fan sequences, with periods of excess sediment supply leading to fan sedimentation through aggradation or progradation. There is a regionally consistent temporal sequence of fan sedimentation throughout the northern Great Basin (Chadwick et al 1984;Bell & Katzer 1987;Harvey et al 1999a;Ritter et al 2000;Harvey 2002a), with pulses of sedimentation associated with periods of more arid climates during the Holocene and prior to the last glacial maximum, perhaps extending back to the last interglacial. Fan stability and/or fanhead entrenchment occurred during the intervening periods of lesser sediment supply.…”

“…They include several stages set into each other and, on the basis of the maturity of the soils on even the youngest of these segments, must predate the last glacial maximum by a considerable period. Various estimates put their probable age as at least 30 ka (Chadwick et al 1984;Bell & Katzer 1987), and were probably formed over periods dating back to the last interglacial in excess of 100 ka, following the previous lake highstand (the Eetza stage of Morrison 1991).…”