David J Nash

University of Brighton · School of Environment and Technology

The Middle Stone Age (MSA) was a time of great human adaptation and innovation. In southern Africa, coastal locations have been viewed as key places for the development of human resource use and behaviour, with the dryness of the continental interior after c.130 ka regarded as both an obstacle to occupation and a limit on behaviour. Newly excavated...

This paper documents the abundance of Stone Age finds in the Middle Kalahari, both through earlier publications and newly documented sites. Results of several decades of Stone Age research are presented through a variety of projects and placed within the context of previous archaeological investigations in the region. We argue for the importance of...

Analyses of the distance over which lithic raw materials were transported for use in stone tool production provide important insights into early human mobility through prehistoric landscapes. This study combines the use of geochemical provenancing, chaîne opératoire analysis and geochronology to examine patterns of lithic raw material procurement a...

Studies of early human occupation of Africa over recent decades have profoundly changed how we understand our early ancestors, their inventiveness and adaptability. The spread of Homo sapiens to new environmental settings, the expansion of diet breadth, the development of more complex technology and the use of personal ornaments have all been recog...

The influence of natural factors such as bioturbation or sediment movement caused by wind and water is a perennial concern for Stone Age site selection and subsequent interpretation. This paper discusses the spatial artefact distribution of five recently excavated, open-air exposed Middle Stone Age (MSA) sites in Ntwetwe Pan, Botswana. The finds co...

The intersection of archaeological material with the landscape is investigated using OSL dating of landforms associated with Middle Stone Age (MSA) archaeology in the Makgadikgadi basin, Botswana. In this study, MSA archaeological sites on the Makgadikgadi pan floor date to two dry periods in the basin during the late Quaternary. Site formation at...

The generation of index-based series of meteorological phenomena, derived from narrative descriptions of weather and climate in historical documentary sources, is a common method to reconstruct past climatic variability and effectively extend the instrumental record. This study is the first to explicitly examine the degree of inter-rater variabilit...

Little is known of the properties of the sarsen stones (or silcretes) that comprise the main architecture of Stonehenge. The only studies of rock struck from the monument date from the 19th century, while 20th century investigations have focussed on excavated debris without demonstrating a link to specific megaliths. Here, we present the first comp...

Narrative evidence contained within historical documents and inscriptions provides an important record of climate variability for periods prior to the onset of systematic meteorological data collection. A common approach used by historical climatologists to convert such qualitative information into continuous quantitative proxy data is through the...

Collections of written materials from the 16th century onwards have been used to explore the historical climatology of Africa. Studies include decadal- to seasonal-scale reconstructions of past rainfall and temperature, and analyses of societal responses to historical extreme events.

Evidence contained within historical documents and inscriptions provides an important record of climate variability for periods prior to the onset of systematic meteorological data collection. A common approach used by historical climatologists to convert such qualitative documentary evidence into continuous quantitative proxy data is through the g...

The sources of the stone used to construct Stonehenge around 2500 BCE have been debated for over four centuries. The smaller “bluestones” near the center of the monument have been traced to Wales, but the origins of the sarsen (silcrete) megaliths that form the primary architecture of Stonehenge remain unknown. Here, we use geochemical data to show...

Understanding the historical dynamics of wildlife distribution and abundance is essential to developing appropriate conservation measures. Here we investigate the occurrence and status of medium-to large-sized fauna (excluding avifauna) for the mountain Kingdom of Lesotho and immediate adjoining regions of South Africa, from the late Pleistocene to...

Recent studies in southern Africa and eastern Australia have demonstrated the feasibility of using a geochemical fingerprinting approach to determine the source locations from which silcrete raw materials were procured prior to their use in stone tool manufacture. The impact of intentional heat treatment of silcrete upon its chemistry, however, is...

During the second half of the 1890s, south-eastern Africa was hit by a drought-driven ecological crisis. Using records previously unexploited for climate and climate impact research, and which cover the area from modern-day Zimbabwe and Botswana to eastern South Africa, this study explores the complexity of this crisis through an analysis of the sp...

Single- to multiple-year drought episodes posed significant challenges for agrarian communities across southern Africa during the nineteenth century and hence are widely recorded in a variety of historical documents. However, the ways in which droughts are articulated, and the focus of individual accounts, vary considerably between different author...

Changing climates affect human societies differently depending on societal structures, cultural perceptions and their relative vulnerability and resilience. In this study, we explore the complex relationship between climate, conflict and society in nineteenth century Zululand. The paper first reviews current debates surrounding the links between cl...

Analyses of aeolianites and associated dune, surficial carbonate and marine terrace sediments from north-central Chile (27° 54′ S) yield a record of environmental change for the coastal southern Atacama Desert spanning at least the last glacial-interglacial cycle. Optically stimulated luminescence dating indicates phases of aeolian dune constructio...

Heat treatment was one of the first transformative technologies in the southern African Middle Stone Age (MSA), with many studies in the Cape coastal zone of South Africa identifying it as an essential step in the preparation of silcrete prior to its use in stone tool manufacture. To date, however, no studies have investigated whether heat treatmen...

Linearity and normalisation verification after implementation of flat-field correction of scene illumination non-uniformity. (TIF)

Williamsons-Hall diagrams of the four unheated samples. (TIF)

Supporting Information for Colour analysis. (DOCX)

Masses of the granulars obtained from each of the sample cubes, and thicknesses of the respective plan-parallel polished slabs used for transmission IR-spectroscopy. Values under ‘Total mass of the granular’ are the total mass of all fragments shattered from a cube. Values under ‘Mass of heat-treated Aliquot’ are the masses of the granular aliquots...

The image acquisition rig used to capture images of silcrete samples. Note the custom sample holder in the foreground and the custom-built hemispherical light source for shadow-free, near-uniform illumination. (TIF)

A typical captured image of a sample (labelled ‘01.450’) located within the custom sample holder. The sample is placed in its standardised location against the background formed by the X-Rite ColorChecker Passport Photo calibration target. (TIF)

Infrared spectrum of WK-13-13 between 5500 cm-1 and 2000 cm-1 compared to a kaolinite reference spectrum in the region of fundamental OH stretching vibrations. Note that the broad H2O absorption band of WK-13-13 is overgrown by two sharp OH stretching vibrations at 3695 cm-1 and 3620 cm-1 on its high frequency side. The bands correspond to the two...

Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all conti...

Analyses of stratigraphic sequences within the paleocanyons of the Hualapai Plateau, Arizona, are important because these deposits offer the only evidence for the Paleogene-Neogene geological history of the Grand Canyon area. In this paper, we focus on the origins and paleoenvironmental significance of the West Water Formation, located within the M...

This study utilises geochemical provenancing of silcrete raw materials, in combination with chaîne opératoire analyses, to explore lithic procurement and behavioural patterns in the northern Kalahari Desert during the Middle Stone Age (MSA). New data from the sites of Rhino Cave, Corner Cave, and ≠Gi in northwest Botswana, combined with earlier res...

Silcrete is a type of duricrust formed by the near-surface accumulation of secondary silica within a soil, sediment, rock or weathered material. A variety of models of formation have been put forward, involving silicification in both pedogenic and non-pedogenic settings. The resulting silcrete types differ in terms of their macroscale characteristi...

Climate variability has been causally linked to the transformation of society in pre‐industrial southeast Africa. A growing critique, however, challenges the simplicity of ideas that identify climate as an agent of past societal change; arguing instead that the value of historical climate–society research lies in understanding human vulnerability a...

Analyses of historical patterns of rainfall variability are essential for understanding long-term changes in precipitation timing and distribution. Focussing on former Natal and Zululand (now KwaZulu-Natal, South Africa), this study presents the first combined annual and seasonal reconstruction of rainfall variability over southeast Africa for the...

Cap structures within silcretes have long been used as a diagnostic indicator of pedogenic silicification. However, a growing number of studies of the micromorphology of non-pedogenic silcretes indicate that this may no longer be appropriate. This paper presents the first systematic investigation of the micro-fabric, geochemistry and mineralogy of...

The Kalahari Desert contains extensive networks of ephemeral and fossil drainage which are potential indicators of past and present neotectonic activity and climate-driven environmental change. An absence of topographic data has hindered our understanding of their development. We present long-profile information for twenty-nine valley networks deri...

The combination of vegetated orange–red dunes , seasonal pans and dry valleys in the Kalahari creates a landscape with outstanding scientific and aesthetic value. This chapter describes the geomorphological features of the Kalahari Desert within South Africa and adjacent areas of Botswana and Namibia, with a special emphasis on aspects that make th...

Tropical cyclones (TCs) represent the most significant natural hazard for the economy and population of Madagascar. Planning for the impacts of future cyclone strikes requires a detailed understanding of the frequency of destructive storms in the past. In this paper, we utilise historical documentary materials to construct an initial framework of T...

Investigations into the climatic forcings that affect the long-term variability of the Indian summer monsoon are constrained by a lack of reliable rainfall data prior to the late nineteenth century. Extensive qualitative and quantitative meteorological information for the pre-instrumental period exists within historical documents, although these ma...

Recent years have seen major advances in the understanding of the historical climatology of tropical and subtropical areas, primarily through the analysis of documentary materials such as weather diaries, newspapers, personal correspondence, government records, and ship logs. This paper presents a critical review of these advances, drawing upon exa...

This study presents the first consolidation of palaeoclimate proxy records from multiple archives to develop statistical rainfall reconstructions for southern Africa covering the last two centuries. State-of-the-art ensemble reconstructions reveal multi-decadal rainfall variability in the summer and winter rainfall zones. A decrease in precipitatio...

Past global climate changes had strong regional expression. To elucidate their spatio-temporal pattern, we reconstructed past temperatures for seven continental-scale regions during the past one to two millennia. The most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the...

Lithic artifacts from the African Middle Stone Age (MSA) offer an avenue to explore a range of human behaviors, including mobility, raw material acquisition, trade and exchange. However, to date, in southern Africa it has not been possible to provenance the locations from which commonly used stone materials were acquired prior to transport to archa...

A growing number of proxy, historical and instrumental data sets are now available from continental Africa through which past variations in temperature can be assessed. This paper, co-authored by members of the PAGES Africa2k Working Group, synthesises published material to produce a record of temperature variability for Africa as a whole spanning...

Past global climate changes had strong regional expression. To elucidate their spatio-temporal pattern, we reconstructed past temperatures for seven continental-scale regions during the past one to two millennia. The most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the...

Introduction Potential climate forcing factors Mediterranean North Africa The Sahara and the Sahel Equatorial Africa Southern Africa Synthesis Directions for future research References

The date of onset of the southwest monsoon in western India is critical for farmers as it influences the timing of crop plantation and the duration of the summer rainy season. Identifying long-term variability in the date of monsoon onset is difficult, however, as onset dates derived from the reanalysis of instrumental rainfall data are only availa...

Why the tropics matter Development of ideas Establishment of the tropical climate system Drivers of tropical environmental change The tropics as drivers of change Extra-tropical forcing Organisation of the volume Acknowledgements References

IntroductionSodium nitrate depositsHalite crustsGypsum crustsCalcreteSilcreteDesert rock coatingsPalaeoenvironmental significance of crustsReferences

Forecasting austral summer rainfall in southern Africa is hampered by a lack of long-term instrumental data. This paper extends the historical record for the subcontinent by presenting the first extensive 19th century climate history for Lesotho derived from documentary evidence. The data sources included unpublished English-, French- and Sesotho-l...

This study presents the first 19th century cold season climate chronology for the Kingdom of Lesotho in southern Africa. The chronology is constructed using a variety of documentary sources including letters, diaries, reports, monographs and newspaper articles obtained from southern African and British archives. Information relating to cold season...

Scope of This VolumeOrganisationSignificance of Geochemical Sediments in LandscapesReferences

This state-of-the-art volume reviews both past work and current research, with contributions from internationally recognized experts. The book is organized into fourteen chapters and designed to embrace the full range of terrestrial geochemical sediments. An up-to-date and comprehensive survey of research in the field of geochemical sediments and l...

Introduction: Nature and General CharacteristicsDistribution, Field Occurrence and Geomorphological RelationsMacromorphological CharacteristicsMineralogy and ChemistryMicromorphological CharacteristicsSilica Sources, Transfers and Precipitation MechanismsModels of Silcrete FormationPalaeoenvironmental SignificanceRelationships to other Terrestrial...

This study uses a range of published and unpublished historical documentary sources to explore the nature of rainfall variability in the Kalahari Desert and adjacent hardveld regions of central southern Africa during the seventeen Pacific El Niño–Southern Oscillation (ENSO) episodes that occurred between 1840 and 1900. Documentary data are used in...

Throughout much of the late eighteenth and early nineteenth centuries, the tropics and subtropics were constructed as a relatively homogenous realm. The supposed ‘pathological potency’ of these regions was assumed to render them particularly hazardous for European constitutions relative to ‘temperate’ locations. The interior of Africa represented o...

Dryland alluvial fans developed along the northern flanks of the Sierra Lisbona in the north-western Vera basin (Almería region, southeast Spain) display negligible amounts of incision despite distal base-level lowering of > 30 m by the modern drainage network. The fans are of early-middle Quaternary age and are graded to a coeval river terrace, no...

This paper documents the first Holocene palaeoecological record for the Okavango Delta, northwest Botswana. Sedimentological, stable carbon isotope and palynological data, supported by conventional and AMS radiocarbon assays, are presented from coring sites at Gauxa Lagoon and the Ncamasere and Tamacha valleys along the western margin of the Okavan...

Groundwater silcretes have been recognized recently as major terrestrial silicon sinks and yet their origins are poorly understood. This paper aims to further the understanding of the micro-fabric, geochemistry and formation of groundwater silcretes, through detailed analyses of silcrete boulders from the South Downs, Sussex, UK. In-depth petrologi...

European ‘acclimatization’ represented a central geographical and medical question throughout the nineteenth century. Prolonged residences by Europeans in the tropics were thought to result in physical and moral deterioration, and women were thought to be particularly vulnerable. Among the first British women to venture into the tropics and sub-tro...

Calcrete–silcrete intergrade duricrusts are an important component of the Kalahari Group sediments of central southern Africa and yet have neither been analysed systematically nor in any detail. In this study, the petrological and geochemical characteristics of suites of calcrete, silcrete and intergrade duricrusts from two fresh, relatively deep e...

This paper presents the first intensive integrated field and laboratory study of an area of typical silcrete occurrence in the UK, and enables parallels to be drawn with in situ silcretes in the neighbouring Paris Basin and other parts of northern Europe. Silcrete distribution in the eastern South Downs is localized and discontinuous, with occurrence...

This paper documents the first application of laser Raman and Fourier transform infrared vibrational spectroscopic techniques (Raman/FT-IR) to the analysis of silcrete. Analyses are undertaken at a reconnaissance level on bulk silcrete samples of varying ages, drawn from a range of geomorphological settings across the Kalahari Desert of Botswana. Re...

Calcretes that form in non-pedogenic settings have been widely reported in the geomorphological and geological literature, yet they are still poorly understood in comparison with pedogenic varieties. This may be because there are assorted types of non-pedogenic calcretes (often loosely referred to as groundwater calcretes, but encompassing groundwa...

The sediments and landforms at the Tsodilo Hills, in the northwestern Kalahari desert, provide an opportunity to directly investigate the late Quaternary wetting and drying of the region from evidence at a single site. Lacustrine carbonates, including incorporated molluscs and diatoms, a lake shoreline feature and stabalised linear dunes were inves...

Nonpedogenic channel calcretes of up to 3.5 m thick occur in a number of locations across the Tabernas Basin in Almerı́a Province, southeast Spain. They represent the last major phase of late Quaternary calcium carbonate cementation to affect this semiarid drainage basin. Channel calcretes are situated within the basal parts of sequences of <12-m-t...

The letters, personal papers, and journals written by British missionaries based at mission stations within and around the Kalahari region of central southern Africa in the nineteenth century provide an invaluable insight into time- and place-specific interactions with local cultures and environments. This article employs a range of unpublished and...

Unpublished materials written by missionaries based at London Missionary Society and Wesleyan Methodist Missionary Society mission stations across the Kalahari region have been used as the primary source for the construction of a historical climatic chronology for central southern Africa for the period 1815–1900. Data from these unpublished documen...

Unpublished documentary materials written by missionaries working for the London Missionary Soclety in the Kalahari Desert of central southern Africa during the nineteenth century have been used to identify historical hydrological events in drainage systems of the region. Analysis and interpretation of missionary correspondence has identified previ...

This paper examines the role that representatives of the London Missionary Society in central southern Africa during the nineteenth century may have played in the development of geographical debates concerning the long-term desiccation of the African continent. Observations on climate included within missionary documents are used to reconstruct a c...