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Abstract The Mojave Desert presents an array of Pleistocene lacustrine deposits and aeolian landforms to which, at times, it has proved challenging to apply luminescence methods. We tested the suitability of K-feldspar post-IR IRSL methods using two sites with independent radiocarbon dating – shorelines at Harper Lake and Silver Lake – considering: 1) overall performance of the post-IR IRSL 225 °C (pIRIR 225) protocol; 2) effect of test dose size on pIRIR 225 D e ; 3) anomalous fading correction of pIRIR 225 ages; 4) preliminary single grain pIRIR 225 results. We observe consistently good performance of the single aliquot pIRIR 225 protocol, with good dose recovery, acceptable recycling ratios, low recuperation and low inter-aliquot scatter. The pIRIR 225 ages for Silver Lake (8.8 ± 0.4 and 11.3 ± 0.5 ka) and Harper Lake (both 25.4 ± 1.4 ka) are in substantially better agreement with the independent dating than low temperature (50 °C) IRSL and quartz OSL ages. pIRIR 225 fading rates are reduced to ∼2.0–2.5% per decade, but there remains a tendency for under-estimation when using uncorrected ages. A need for fading correction is further implied at Harper Lake via comparison with multi-elevated temperature (MET)-PIR age plateaus and pIRIR 290 measurements, although at the younger Silver lake site these methods produce ages nearly identical to the uncorrected pIRIR 225 ages. Preliminary single grain pIRIR 225 measurements suggest a ∼25–30% usable grain yield. At Silver Lake the single grain and single aliquot ages agree well despite over-dispersion of the single grain equivalent dose distribution. At Harper Lake the single grain and single aliquot pIRIR 225 ages also agree well, although a population of insensitive, lower D e grains is observed. These grains are not associated with significantly higher fading rates. Highlights • Comparison of post-IR IRSL with independent 14C dating at two sites. • pIRIR 225 ages show better agreement than quartz OSL and 50 °C IRSL. • pIRIR 225 ages still require fading correction (g-values ≥2%). • Moderate test dose sizes (10–30%) produce best age estimates. • Variability in single grain sensitivity and D e distributions. [ABSTRACT FROM AUTHOR]

Topography fundamentally influences the distribution and morphology of aeolian landforms via the modification of surface wind flow and the creation of space for sediment deposition. This has been observed at both landform (individual topographic dune forms) and macro-landscape (sand sea) scales. Although previous studies have considered several aspects of the impact of topography on aeolian landforms, the patterns of landscape-scale aeolian sediment accumulation that emerge at the meso-scale, within topographically complex environments have received less consideration. To address this, we present an approach that combines information on the presence of surficial sand (via remote sensing) with the morphometric feature classification method, LandSerf. Using the Cady Mountains in the Mojave Desert as a case study, we explore the relationships between sand cover and topographic indices over length scales of 102–103 m. Field observations are then used to refine our understanding of these patterns. Aeolian deposits across the Cady Mountains are strongly controlled by the topography. Although sand cover is often continuous and highly variable in depth, four archetypal "accommodation space types" are identified from the morphometric analysis: Slopes, Plains, Valley-Fills, and Slope-Valley composite. Specific aeolian landforms within these accommodation spaces may manifest as sand ramps and climbing - falling dunes, particularly on mountain front Slopes, and as sand sheets on downwind Plains within the mountain block. In areas of high sediment supply these may also coalescence, as exemplified by the extensive and compositionally complex Slope-Valley composites in the northern Cady Mountains. In conjunction with field observations, we argue that topography, moderated by proximity to sediment supply, strongly influences the character of the aeolian sedimentary record. However, even within the relatively complex landscape studied here, 90% of the mapped sand accumulation is associated with the four identified accommodation space types. The implication is that areas of such complex topography are amenable to analysis within the scheme outlined and that this can potentially be used to support interpretations of accompanying dune chronologies. • First attempt to analyse large-scale patterns of aeolian sediment accumulation within complex topography. • Combined remote sensing-morphometric analysis of aeolian sand-topography relations. • Three accommodation space types and one composite type account for majority of sand occurrence • Aeolian preservation at any locale is contingent on topography and sediment supply. [ABSTRACT FROM AUTHOR]