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Drainage divide migration alters the geometry of drainage basins, influencing the distribution of water, erosion, sediments, and ecosystems across Earth’s surface. The rate of divide migration is governed by differences in erosion rates across the divide and is thus sensitive to spatiotemporal variations in tectonics and climate. However, established approaches for quantifying divide migration rates offer only indirect evidence for the motion of the divide and provide only migration rate averages. Consequently, transience in divide migration cannot be resolved, hindering the ability to explore environmental changes that drive the dynamics of such potential transience. Here, we study a set of datable terraces identified as markers of paleo-divide locations, which provide direct evidence for the paleo motion of the divide. The location and age of the terraces reveal intermittent divide migration at timescales of 10⁴to 10⁵y, with phases of rapid migration—at rates more than twice the average—which coincide with documented regional paleoclimate fluctuations. These findings highlight the intermittent nature of divide migration dynamics over geomorphic timescales and its potential sensitivity to climate changes, underscoring the impact of such changes on the planform evolution of drainage basins. 

The Amazonia biome hosts upland closed and open vegetation ecosystems, in which the current biogeographical patterns relate to the evolution of the physical landscape. Therefore, understanding the origin and timing of the substrates supporting different ecosystems is indispensable for better comprehension of Amazonian biogeography. Here we used quartz optically stimulated luminescence (OSL) and thermally transferred optically stimulated luminescence (TT-OSL) for dating sandy substrates of closed and open vegetation environments in Central and Eastern Amazonia, from both outcrop and drill core samples (Autazes core: PBAT-15-43). These sandy substrates present ages ranging from 1 ka up to almost 2 Ma, that were primarily interpreted as depositional ages of fluvial terraces. Moreover, ages are discussed in terms of potential geomorphic processes leading to the formation of substrates, such as soil mixing and apparent age of quartz from the parent bedrock. The coupling between OSL and TT-OSL techniques allow us to date sedimentary deposits covering the whole Quaternary, which implies a new time window for the Amazonia history. 

The development and application of luminescence dating and dosimetry techniques have grown exponentially in the last several decades. Luminescence methods provide age control for a broad range of geological and archaeological contexts and can characterize mineral and glass properties linked to geologic origin, Earth-surface processes, and past exposure to light, heat, and ionizing radiation. The applicable age range for luminescence methods spans the last 500,000 years or more, which covers the period of modern human evolution, and provides context for rates and magnitudes of geological processes, hazards, and climate change. Given the growth in applications and publications of luminescence data, there is a need for unified, community-driven guidance regarding the publication and interpretation of luminescence results. This paper presents a guide to the essential information necessary for publishing and archiving luminescence ages as well as supporting data that is transportable and expandable for different research objectives and publication outlets. We outline the information needed for the interpretation of luminescence data sets, including data associated with equivalent dose, dose rate, age models, and stratigraphic context. A brief review of the fundamentals of luminescence techniques and applications, including guidance on sample collection and insight into laboratory processing and analysis steps, is presented to provide context for publishing and data archiving.