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Luminescence characteristics of quartz and feldspar allow to discriminate sediments from different source areas. Particularly, sensitivity of optically stimulated luminescence (OSL) and thermoluminescence (TL) signals of quartz and infrared‐stimulated luminescence (IRSL) of feldspar from Quaternary sediments has been used for provenance analysis. These properties change due to source area denudation rates and sediment reworking, which drive the number of burial irradiation‐solar exposure cycles of sediment grains in surface systems. Here, we use for the first time a similar approach to interpret the geomorphic conditions of source areas of Silurian to Triassic siliciclastic sedimentary units of the intracratonic Parnaíba Basin in northeast Brazil. Luminescence measurements were performed on sand grains, and statistical tests were applied to evaluate differences in luminescence properties within and across stratigraphic units. We explored the position of well‐known "110°C" (TL110) and "325°C" (TL325) TL peaks of quartz as proxies to discriminate stratigraphic units with similar lithological assemblages. OSL and TL sensitivities as well as the dominance of the so‐called fast OSL component increase from Silurian to Triassic sedimentary units, while the IRSL sensitivity decreases towards younger stratigraphic units. These patterns point to source areas with decreasing denudation rate and higher sediment recycling over basin filling time, leading to decreasing feldspar concentration and quartz luminescence sensitisation. Major changes in luminescence properties coincide with regional unconformities. This is attributed to physical landscape changes leading to shifts in the relief of source areas and basin sediment recycling. The TL110 peak position is similar across stratigraphic units, but the TL325 peak position has significant variation, with values between 324°C and 334°C, allowing its use for stratigraphic discrimination. Changes in OSL and TL characteristics of quartz sediment grains are preserved during long‐term burial (108 Ma), representing a new tool for interpreting basin evolution and to perform stratigraphic analysis of ancient siliciclastic successions. [ABSTRACT FROM AUTHOR]

The present research work reviews the age models of three previously studied loess sections across 700 km in the loess belt of the Pampean region in central Argentina. The loess sections were investigated for the first time through high-resolution luminescence dating in order to determine the chronology of the loess deposits and its temporal correlation with important palaeoclimatic records of the Southern Hemisphere. Reliable estimations of mass accumulation rates (MARs) for loess were used to infer the temporal dust flux variation during the last glacial/interglacial transition in southern South America. The new age models have significant differences compared to the previously published ones of likely Last Glacial Maximum (LGM) ages. The three studied sections showed general bimodal grain-size distributions consistent with multiple sources contributing dust to the Pampas. It is observed that higher MARs values are associated with an increased presence of finer loess. Increases in loess accumulation are coeval with climatic transitions from wetter to drier periods in the Puna-Altiplano Plateau, and high MARs are related to synchronous climatic shifts to humid conditions in the Pampean plain. Contrasting with dust fluxes observed in the more distal palaeoarchives (i.e., the South Atlantic Ocean and the Antarctic ice sheet) the new data suggest increased dust accumulation in the Pampas during the Antarctic Cold Reversal (ACR) and the Holocene. This supports the idea that changes related to atmospheric transport efficiency can better explain dust flux variations observed over glacial/interglacial periods in distant palaeoarchives. • New loess OSL age models have differences compared to previous data. • New age models cover ∼38 ka of terrestrial history of dust deposition in the Pampas. • Reliable estimations of mass accumulation rates are reported for the first time. • Loess accretion agrees with increased Altiplano deflation and a wetter Pampas. • Changes of transport efficiency better explain dust flux in distant palaeoarchives. [ABSTRACT FROM AUTHOR]

Abstract Over long-term geological scales, the position and vertical movements of the coast are considered to be among the most important effects resulting from first-order plate tectonics interactions in the subduction zones. However, the relationship between short-term vertical deformation driven by earthquakes and long-term coastal uplift in the Andean subduction contact of northern Chile has not been thoroughly elucidated to date. Based on precise radiocarbon dating and geomorphological analysis of littoral deposits in the Mejillones Peninsula at the southern edge of the major northern Chile seismic gap, we report a drastic increase in coastal uplift since marine isotope stage 3 (MIS 3) with uplift rates one order of magnitude more rapid than previously in the Late Pleistocene. Geomorphological evidence supplied by Holocene littoral deposits and marine terraces shows that this tectonic regime could be operating at present. Together with new geodetic data following the 2007 M w 7.7 Tocopilla event, these observations indicate that coastal uplift results from cumulative coseismic vertical displacement with low subsequent interseismic subsidence recovery driven by both deep-moderate and large megathrust earthquakes. We suggest that the accelerated coastal uprising and earthquake rate over the past ∼44 ka demonstrated in this work results from changes involving the entire subduction contact between the Nazca and South American plates in northern Chile. Highlights • We report for the first time emerged MIS 3 deposits in northern Chile. • We report high Late Quaternary uplift rate values in the coastal Central Andes. • We evidence slow vertical recovering since the 2007 M w 7.7 Tocopilla megathrust. • Rapid coastal uplifting resulted from both large and moderate subduction earthquakes. • We propose the onset of a millennial-scale seismic regime at ∼44 ka. [ABSTRACT FROM AUTHOR]