Search

• First map of primary and secondary chert sources in nothern Apulia. • Multivariate statistics applied to a compositional mixed dataset of chert. • Peschici Fm. mines were better differentiated than Maiolica Fm. ones. • Polygenic secondary chert sources of Tavoliere mirror the Appenine and Gargano origin. During the Neolithic period, near the North-Eastern coast of the Gargano promontory (Apulia Region, Italy), an important network of mines represented the most ancient European example of systematic exploitation of primary chert sources. These high-quality raw materials were traded between prehistoric communities living on both sides of the Adriatic Sea. However, the Gargano promontory is not the only area of the Apulia Region with chert sources. Secondary sources of the Tavoliere plain deposits and primary sources of the Southern Apennines must be considered in addition to the Gargano chert-bearing limestones. This paper provides an overview of chert sources distribution in the Gargano and Tavoliere plain through a chert sources map based on up-to-date geological and archaeological information. The map represents the first lithic procurement mapping in the Region and it is a very useful tool for planning sampling activities and detect the potential chert sources exploited in Neolithic times. The map was used for sampling pebbles near the coast and inland of the investigated area. A non-destructive multi-parametric protocol for chert investigations (NM-PCI) method was applied to all the collected secondary samples. The results were compared at first with those of the Gargano mines. The output of the partition around medoids (PAM) procedure shows, as a general trend, that primary sources are well grouped, while secondary sources show less clear compositional fingerprints. However, the features of the coastal and inland pebbles are quite different. [ABSTRACT FROM AUTHOR]

Abstract The Caminada Headlands is a beach and dune system near Port Fourchon in coastal Louisiana that provides natural protection for back barrier marshes against storm surges and wave overtopping. Due to significant shoreline erosion and regional subsidence, a beach and dune restoration project was initiated in 2012 to replenish the shoreline front. Because of the underlying soft deltaic sediments, this restoration effort was expected to cause significant increase in the applied vertical stress and thus sediment settlement. To quantify the degree of settlement occurring within the compressive sediment layers and the fill, extensive geotechnical investigations were conducted for design and installation of settlement plates and subsurface settlement anchors to monitor the field performance. This paper presents the geological and geotechnical investigations, measured material properties, and corresponding empirical correlations developed from fifty-one (51) laboratory consolidation tests. The pre- and post-survey elevations of the site are also used to determine the change in vertical stress with depth at the instrumented sites. The measured material properties and vertical stress profiles can be used to calibrate the numerical modeling of the sediment and fill settlements. [ABSTRACT FROM AUTHOR]

Submerged Artificial Headland (SAH) and Detached Artificial Headland (DAH) are two types of modified artificial headland to provide better water exchange at slightly weakening beach protection effect compared to Traditional Artificial Headland (TAH). In this paper a numerical investigation is conducted on performances of SAH and DAH in a beach nourishment project. The beach protection and water exchange are considered respectively. A shoreline model and a constituent transport model are set up to simulate the post-project shoreline change and water exchange. The results of shoreline changed model show that both the SAH and DAH have good performance in protecting the beach behind them, while in SAH case the shoreline has a smoother shape. The effects of eroding and silting characteristics of the beach on the performance of SAH and DAH are also discussed. The SAH and DAH have similar performance of reducing the flushing time and improving the water exchange in the area behind the artificial headlands compared to TAH. The effect of tidal condition on the flushing time is also discussed. It is suggested that both SAH and DAH are feasible and effective measures to strengthen the water exchange at the cost of an acceptable loss of beach protection. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive study of headland bypassing around seven headlands with different orientations and degrees of wave and tide-induced current exposure, located on the northern shore of Santa Catarina island, southern Brazil. It encompasses an extensive dataset including detailed in situ measurements of bathymetry, beach profiles, sediment transport (traps), waves, currents and tides. The entrained sediment decreased in magnitude towards the more sheltered coast while maintaining comparable sediment grain distributions, supporting the hypothesis of a connection between beaches. Based on in situ measurements, a numerical model was calibrated (waves, currents and tides) and validated, with errors representing 11% of the magnitude of the measurements. Furthermore, three sediment transport formulae were tested to identify the one that best reproduced the processes at the study site. A model using tides, winds and full wave spectra as input was run to identify the general (net) trend of annual sediment transport in the study area aiming to identify if/where headland bypassing occurs. The results show that headland sand bypassing does occur in the study area confirming the anticlockwise sediment transport pathway. The present work highlights the role of sediment bypassing on embayed-headland bound beaches, which are usually considered to be closed cells. [ABSTRACT FROM AUTHOR]

South Africa's southwestern Cape occupies a critical transition zone between Southern Hemisphere temperate (winter) and tropical (summer) moisture-bearing systems. In the recent geological past, it has been proposed that the relative influence of these systems may have changed substantially, but little reliable evidence regarding regional hydroclimates and rainfall seasonality exists to refine or substantiate the understanding of long-term dynamics. In this paper we present a mid-to late Holocene multi-proxy record of environmental change from a rock hyrax midden from Katbakkies Pass, located along the modern boundary between the winter and summer rainfall zones. Derived from stable carbon and nitrogen isotopes, fossil pollen and microcharcoal, these data provide a high resolution record of changes in humidity, and insight into changes in rainfall seasonality. Whereas previous work concluded that the site had generally experienced only subtle environmental change during the Holocene, our records indicate that significant, abrupt changes have occurred in the region over the last 7000 years. Contrary to expectations based on the site's location, these data indicate that the primary determinant of changes in humidity is summer rather than winter rainfall variability, and its influence on drought season intensity and/or length. These findings are consistent with independent records of upwelling along the southern and western coasts, which indicate that periods of increased humidity are related to increased tropical easterly flow. This substantially refines our understanding of the nature of temperate and tropical circulation system dynamics in SW Africa, and how changes in their relative dominance have impacted regional environments during the Holocene. [ABSTRACT FROM AUTHOR]

The Palaeo-Agulhas Plain formed an important habitat exploited by Pleistocene hunter-gatherer populations during periods of lower sea level. This productive, grassy habitat would have supported numerous large-bodied ungulates accessible to a population of skilled hunters with the right hunting technology. It also provided a potentially rich location for plant food collection, and along its shores a coastline that moved with the rise and fall of sea levels. The rich archaeological and paleontological records of Pleistocene sites along the modern Cape south coast of South Africa, which would have overlooked the Palaeo-Agulhas Plain during Pleistocene times of lower sea level, provides a paleoarchive of this extinct ecosystem. In this paper, we present a first order illustration of the " palaeoscape modeling " approach advocated by Marean et al. (2015). We use a resourcescape model created from modern studies of habitat productivity without the Palaeo-Agulhas Plain. This is equivalent to predominant Holocene conditions before recent landscape modifications for farming. We then run an agent-based model of the human foraging system to investigate several research questions. Our agent-based approach uses the theoretical framework of optimal foraging theory to model human foraging decisions designed to optimize the net caloric gains within a complex landscape of spatially and temporally variable resources. We find that during the high sea-levels of MIS 5e (+5–6 m asl) and the Holocene, the absence of the Plain left a relatively poor food base supporting a much smaller population relying heavily on edible plant resources from the current Cape flora. Despite high species diversity of plants with edible storage organs, and marine invertebrates, encounter rates with highly profitable resources were low. We demonstrate that without the Palaeo-Agulhas Plain, human populations must have been small and low-density, and exploited plant, mammal, and marine resources with relatively low caloric returns. The exposure and contraction of the Palaeo-Agulhas Plain was likely the single biggest driver of behavioural change during periods of climate change through the Pleistocene and into the transition to the Holocene. • Agent-based model of Later Stone Age human foraging in coastal South Africa. • Reconstructed food resource landscape including mammals, shellfish, and plants. • Sustainable population is under 20 individuals/100 km^2. • Long foraging days (10 + hours per day) and small groups needed to survive. • Edible plants, including USOs, make up 80% or more of the diet. [ABSTRACT FROM AUTHOR]