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Dating the construction of dry-stone walls is challenging since such structures are typically built without any mortar that can be used for dating. Rock surface luminescence dating is a developing dating method that could advance chronological insights from structures constructed using dry-stone techniques. This study explores rock surface luminescence dating by targeting dry-stone walls from two enclosure complexes and a hut located in the pastoral upland landscape in Val di Sole, Italy. Gneissic rocks were collected from the dry-stone walls, including surfaces that were either exposed or covered (buried) during the time of sampling. Their respective exposure and burial histories were investigated by measuring the luminescence intensity in feldspar minerals from polymineral rock slices. From covered rock surfaces from one enclosure complex, we calculated recent burial ages (∽ 200 a) from one rock, and burial of ∽ 500 a (bottom surface) and 3750 ± 660 a (top surface) from a second rock. The top surfaces of two additional rocks date the construction of an adjacent hut to the Early Middle Ages. The luminescence-depth profile from one such rock has a complex exposure and burial history, including events that predate the hut's construction. Fitted exposure ages from a second enclosure complex suggest with significant errors either a recent age (<10 a) or construction during the 19th century AD. Burial dating using rock surface luminescence dating appears feasible for dry-stone walls provided that the rock surface was sufficiently exposed before being incorporated into the structure; here, the gneissic surfaces were bleached to depths of ∽ 0-2 mm before the last burial. Contrariwise, exposure dating generally underestimates the expected age. The variation in ages observed from our rock surfaces indicates that the degree of preservation of the wall, the position of the rock, erosion, and knowledge regarding the general archaeological setting are essential to interpreting the estimated ages. In this study, rock surface luminescence dating provides new, previously inaccessible chronological data with implications for interpreting human activities in the alpine areas of Val di Sole. [ABSTRACT FROM AUTHOR]

The Triassic succession of the central Southern Alps (Italy) is stacked into several units bounded by south-verging low-angle thrust faults, which are related to two successive steps of crustal shortening. The thrust surfaces are cut by high-angle extensional and strike-slip faults, which controlled the emplacement of hypabissal magmatic intrusions that post-date thrusts motions. Intrusion ages based on SHRIMP U-Pb zircon dating span between 42 ± 1 and 39 ± 1 Ma, suggesting close time relationships with the earliest Adamello intrusion stages and, more in general, with the widespread calc-alkaline magmatism described in the Southern Alps. Fission-track ages of magmatic apatites are indistinguishable from U-Pb crystallization ages of zircons, suggesting that the intrusion occurred in country rocks already exhumed above the partial annealing zone of apatite (depth < 2-4 km). These data indicate that the central Southern Alps were already structured and largely exhumed in the Middle Eocene. Although we describe minor faults affecting magmatic bodies and local reactivations of older structures, no major internal deformations have occurred in the area after the Bartonian. Neogene deformations were instead concentrated farther south, along the frontal part of the belt. [ABSTRACT FROM AUTHOR]