Glaciation of the Upper Forth River Catchment,Tasmania

The Upper Forth Valley was glaciated on at least four occasions during the late Cainozoic. The two most extensive glaciations were no younger than early Pleistocene in age. During the last glaciation the limited ice catchment at the head of the valley nourished only a short valley glacier with separate glaciers forming in the tributary valleys to the west During earlier glaciations the Forth catchment was invaded by ice from the Mersey Valley to the east.     

Reconstruction of the Bulgobac Glacial System,Pieman River Basin,Western Tasmania

During the Early Pleistocene Bulgobac Glaciation, a piedmont glacial system extended into the valleys west of the West Coast Range of Tasmania. The ice that fed this extensive system originated mainly to the south and east on the western Central Highlands and northern Tyndall Mountains. The palaeo-equilibrium line lay to the east of the West Coast Range. Reconstruction of the palaeoglacial system indicates that ice-surface gradients reached only ~10–15 m km^-1 over much of the system to the west of the equilibrium line, although the ice fronts were steep and rapidly ablating. The nature of the piedmont glacier is consistent with the build up of ice behind the topographic barrier of the West Coast Range. This would have resulted in ice thickening, maintained and perhaps accentuated by high precipitation as well as by the location of the equilibrium line well to the west of the western Central Highlands.     

ROCK GLACIERS, SOUTHWEST YUKON

Two distinct types of rock glaciers occur in southwest Yukon. One results directly from glaciation, with the production of abundant debris over glacier ice. The other forms during and after deglaciation, when instabilities develop in deposits and when ice included in these deposits responds to climatic change.     

The last glaciation in the Western Mourne Mountains,Northern Ireland

During the late‐Midlandian (25–13 ¹⁴C ka BP), the last Irish Ice Sheet was thicker in the Western Mourne Mountains than previously argued. Geomorphological and sedimento‐logical analysis shows that regional ice from the Irish Ice Sheet spilled over the mountains, reaching a major limit 5 km along Pigeon Rock Valley. These findings differ from the previous view that a local valley glacier occupied the valley during this period. The pattern of deglaciation was reconstructed using glacial and periglacial evidence. A complex topographic environment in the upper reaches of the valley suggests that regional ice stagnated as it wasted away. During the Nahanagan Stadial (Younger Dryas, ca. 11–10 ka ¹⁴C BP) an arcuate ridge was formed on the western flank of the valley. Calculations suggest that the Equilibrium Line Altitude, influenced by topographic conditions favourable for snow accumulation, was approximately between 1736 m and 1386 m lower during the Nahanagan Stadial than at present.     

On the Identification of Ænon

Abstract

Combined archaeological data from the Central Jordan Valley indicates that small agricultural villages and a few public buildings occupied the area during the first half of the 10^th century BC, all grouped along well-organised irrigation systems. A regional conflagration ended the occupation around 950 BC, after which most of the Central Jordan Valley was deserted for approximately one century. This occupational gap coincided with a period of decreased precipitation. During this arid phase the area was visited by mobile groups who used the summits of the settlement mounds for animal holding and sparse industrial activities. According to the topographical list of Shoshenq I, there were at least four settlements in the Central Jordan Valley: Adamah, Succoth, Penuel and Mahanaim. These places were apparently important enough in c. 925 BC for the Egyptians to neutralise them. But where are the remains of these settlements? This study deals with the intriguing disjunction between archaeological and textual evidence.     

Late Weichselian deglaciation and sea level history of St Jonsfjorden,Spitsbergen: A contribution to ice sheet reconstruction

The elevation and age of surveyed shorelines in St Jonsfjorden, western Spitsbergen, provide a chronology for Late Weichselian deglaciation and a proxy for former ice thickness. Support is provided for previous reports of two sets of shorelines on NW Spitsbergen, the oldest (at 60 m in St Jonsfjorden) dating to a pre‐late Weichselian glaciation and the youngest documenting postglacial rebound. The remarkable survival of the older shorelines suggests that a large area of NW Spitsbergen was either covered by protective, cold‐based ice or was subject to only local glaciation during the late Weichselian even though glacier ice extended to the shelf edge in the Isfjorden Trough. A marine limit of 46 m at the mouth of St Jonsfjorden is compatible with the regional late Weichselian marine limit (LWML) dated to ～13 ka BP. A partial relative sea level curve and equidistant shoreline diagram are produced for St Jonsfjorden and used in conjunction with relative sea level curves based on data from previous studies to produce an isobase map for 9 ka BP. The curves indicate that western sites were subject to initial slow emergence followed by rapid emergence between 10 ka and 8.2 ka BP, trends characteristic of areas affected by a full glacial sea or at least subject to early break up of a thin or discontinuous glacier ice cover. A step in the 9 ka BP shoreline long profile over the western end of the peninsula separating Isfjorden and van Mijenfjorden suggests that Holocene neotectonics may have produced anomalously high rebound rates in that area.     

The last glaciers in part of the South East Grampians

In an area of 400 sq km in the south east Grampians including Glen Esk, Glen Clova and part of Glen Muick the limits of former corrie glaciers, valley glaciers and a plateau ice‐cap with associated outlet glaciers have been mapped. The limits of the former corrie and valley glaciers are often clearly defined by end moraines, boulder‐strewn ground, the down‐valley termination of hummocky moraines and/or the limits of meltwater channel systems, while in suitable locations outwash terraces usually occur. The glaciers are considered to have formed during the Loch Lomond (pollen zone III) Readvance, when new glaciers developed in upland sources following complete ice‐sheet decay. The readvance was accompanied in granite areas by the formation of large solifluction lobes, these lobes being found only outside the mapped ice limits. The interpretations presented are not in accord with those recently given by D. E. Sugden for the western Cairngorms.     

A Fresh Look at the Egyptian Environment of the Pharaonic Period

Abstract

The article deals with the territorial history of the southern steppe areas of the Levant in the period between ca. 1050–750 BCE. In the early days of the Iron Age, until the mid-9^th century BCE, parts of them, were ruled by local desert entities: in the late Iron I a Moabite polity and in the early Iron IIA and the early years of the late Iron IIA the Tel Masos-Beer-Sheba-Negev Highlands Highlands entity. This situation changed in the later years of the Iron IIA as a result of Damascus' rise to hegemony in the Levant. In the second half of the 9^th century BCE Judah, under Damascene domination, expanded for the first time into the Beer-Sheba Valley. In the first half of the eighth century BCE, with the revival of Assyrian power in the days of Adad-nirari III, Damascene authority was replaced by north Israelite domination in the south.     

Obituaries

Abstract

A rich variety of processes have modified the glacial landscape of the Scottish Highlands since the last glaciers disappeared 11,500 years ago. Many of these processes can be described as paraglacial (glacially-conditioned): retreat of glacier ice has resulted in exposure of metastable sediment sources (rock slopes, drift-mantled slopes and valley-floor glacigenic deposits) that have been reworked over a range of timescales. Much of the reworked sediment has been deposited in paraglacial sediment stores (talus accumulations, debris cones, alluvial fans, valley fills, river terraces and deltas). The trajectory of paraglacial sediment transfer can be approximated by an exhaustion model. A corollary of this model is that all sediment stores eventually undergo a change from net accumulation to net erosion, reflecting the non-renewable nature of sediment sources. This concept helps to explain why most talus accumulations, debris cones and alluvial fans in the Highlands are now relict, and why many floodplains appear to have experienced an initial period of aggradation followed by later river incision and terrace development. Since deglaciation, rock slopes have experienced paraglacial stress release due to differential deglacial unloading. Many rock slopes have remained stable or experienced gradual adjustment through intermittent rockfall. At over 600 sites, however, large-scale rock-slope failure has occurred, either in the form of catastrophic failure with complete or arrested debris runout, or as major slope deformations. Modification of drift-mantled slopes has been dominated by rainstorm-generated debris flows activity, which have stripped sediment from slopes and redeposited it in debris cones. Radiocarbon dating of buried organic horizons shows that debris flows have occurred intermittently throughout the Holocene. Snow avalanches have played only a localized role in paraglacial sediment transfer. The Holocene alluvial history of the Highlands is poorly understood. Some alluvial fans formed during a few exceptional flood events, and there is evidence that postglacial floodplain aggradation peaked in the late Holocene and was succeeded by floodplain incision and terrace development, possibly reflecting upstream reduction in paraglacial sediment supply. Other processes have operated independently of glacial conditioning. The effects of wind action are dominant in the coastal zone, forming dunefields through aeolian reworking of beach sand, and on plateaux in the form of deflation surfaces and sand sheets. Extensive erosion of plateau-top sands and aeolisols occurred in the period AD 1550–1700, a period of exceptional storminess. Small-scale periglacial processes have also been active on high ground throughout the Holocene, including granular weathering of exposed rock surfaces, the development of small-scale frost-sorted patterned ground on unvegetated terrain, and slow downslope movement of solifluction sheets, solifluction lobes and ploughing boulders.     

GLACIATION OF BONAVISTA PENINSULA, NORTHEAST NEWFOUNDLAND

Over Bonavista Peninsula, in northeast Newfoundland, ice-flow directional indicators reveal two styles of glaciation. The inner part was glaciated by ice of the Newfoundland Ice Cap, flowing northeast but drawn down strongly into deep channels in Bonavista and Trinity bays and basally deflected northward by a line of hills bisecting the peninsula. The outer peninsula was almost completely glaciated by the contiguous, dynamically independent Bonavista Ice Divide, with coastward flow. Near the northeast extremity a low plateau, mantled with blockfield and bearing no obvious traces of glaciation, is flanked by a subdued end moraine. The moraine is argued to represent the local entire Wisconsinan glaciation limit. Evidence from soil development on the moraine and elevations of emerged post-glacial shore features, as well as from comparison with glacial history in nearby areas, is used to argue a late Wisconsinan (pre-12,000–13,000 BP) age for the later part of glaciation. Evidence of widespread till deposition far offshore can be harmonized with evidence of incomplete Wisconsinan glaciation onshore by postulating persistent discharge of inland ice through the deep, compound fiord basins that flank Bonavista and other east Newfoundland peninsulas Les indicateurs du passage des glaciers dans la péninsule de Bonavista située au nord-est de Terre-Neuve signalent l'oeuvre de deux styles de glaciation. La Calotte Glaciaire de Terre-Neuve recouvrait tout I'intérieur de la Péninsule; se déplaçantvers le nord-est, elle était forcee de suivre par les baies profondes de Bonavista et de Trinité, et détournée à sa base en direction du nord par les collines qui franchissent la péninsule du nordau sud. Pour sa part, I'extérieur de la péninsule gisait entièrement sous le Diviseur Glaciaire Bonavista, qui tout en étant contigu obéissait à une dynamique indépendante et s'écoulait en direction des côtes. A I'extrémité nord-est de la pénin sule, sous un manteau de blocs rocheux, se trouve un bas plateau qui ne porte aucune trace de glaciation et qui est bordé d'une fine moraine terminale. Selon l'argument proposé, cette moraine représente en cet endroit la limite extrême des glaciers du Wisconsin. Des indices provenant de la formation des sols sur cette moraine et des hauteurs atteintes par la mer postglaciaire, de même qu'une comparaison avec l'histoire des glaciations dans les zones environnantes, permettent d'avancer que la fin de la dernière glaciation remonte à celle du Wisconsin (avant 12 000 à 13 000 ans AP). Des liens existent entre les dépots très répandus de till, loin au large des côtes, et les indices d'une glaciation incomplète durant le Wisconsin sur ces côtes, dans la mesure où l'on postule qu'il y eut une décharge soutenue de glace en provenance de l'intérieur, le long des fiords profonds et complexes qui bordent la peninsule de Bonavista de même que d'autres péninsules de Terre-Neuve.     

Impacts of Pleistocene glaciation on large‐scale groundwater flow and salinity in the Michigan Basin

Pleistocene melting of kilometer‐thick continental ice sheets significantly impacted regional‐scale groundwater flow in the low‐lying stable interiors of the North American and Eurasian cratons. Glacial meltwaters penetrated hundreds of meters into the underlying sedimentary basins and fractured crystalline bedrock, disrupting relatively stagnant saline fluids and creating a strong disequilibrium pattern in fluid salinity. To constrain the impact of continental glaciation on variable density fluid flow, heat and solute transport in the Michigan Basin, we constructed a transient two‐dimensional finite‐element model of the northern half of the basin and imposed modern versus Pleistocene recharge conditions. The sag‐type basin contains up to approximately 5 km of Paleozoic strata (carbonates, siliciclastics, and bedded evaporites) overlain by a thick veneer (up to 300 m) of glacial deposits. Formation water salinity increases exponentially from <0.5 g l^?1 total dissolved solids (TDS) near the surface to >350 g l^?1 TDS at over 800 m depth. Model simulations show that modern groundwater flow is primarily restricted to shallow glacial drift aquifers with discharge to the Great Lakes. During the Pleistocene, however, high hydraulic heads from melting of the Laurentide Ice Sheet reversed regional flow patterns and focused recharge into Paleozoic carbonate and siliciclastic aquifers. Dilute waters (<20 g l^?1 TDS) migrated approximately 110 km laterally into the Devonian carbonate aquifers, significantly depressing the freshwater‐saline water mixing zones. These results are consistent with ¹⁴C ages and oxygen isotope values of confined groundwaters in Devonian carbonates along the basin margin, which reflect past recharge beneath the Laurentide Ice Sheet (14–50 ka). Constraining the paleohydrology of glaciated sedimentary basins, such as the Michigan Basin, is important for determining the source and residence times of groundwater resources, in addition to resolving geologic forces responsible for basinal‐scale fluid and solute migration.     

New Data on the Relief Development of the South Shetland Islands,Antarctica

Abstract

During several expeditions to the Antarctic Peninsula and the neighbouring islands, samples were collected from different sediments which contained datable materials or which were datable with new techniques. Thus it became possible to develop, together with our geomorphic field data, some new ideas on relief development at the rim of the Antarctic continent as well as on the glacial history of the area studied.

Planation surfaces in this area seem to be fairly old. For example, the prominent marine erosion surface on Fildes Peninsula, 35–45 m above mean sea level, is probably older than 85 000 years – older than the last interglacial period and the penultimate glaciation. All Holocene beaches, which are situated between 20 m and the present coastline, were formed during the last 6000 years.

Before 6000 BP the islands were still completely glaciated. The breakdown of the ice cover to nearly the present extent must have been extremely abrupt, taking no more than 1000 years (6000 to 5000 BP). Between 3000 and 1000 BP there were at least two re-advances. These advances were restricted to the prominent outlet glaciers, which followed pre-existing valleys.     

Mugwort Lore

I examine Gaelic ‘folk’ cures for insanity in the Highlands, first reflecting on the fact that this is an under-researched subject and then examining the cures described in various collections of Highland folklore. The paper looks at two of the most popular sites in the Highlands for curing madness, St Fillan's Well in the south-east Highlands and Loch Maree in the north-west, discussing the similarities and differences in the accounts of cures taking place in these locations. The nature of these accounts suggests a fluid and socially negotiable oral tradition that existed until at least the late nineteenth century. The power of these particular geographical locations in a narrative framework of curing and healing madness persisted for several centuries, even as specific practices changed over time and older supernatural belief systems faced shifting paradigms of medicine and psychiatry.     

Scottish landform examples 45: Sgriob na Caillich: a landslide-sourced medial moraine on the Isle of Jura

ABSTRACT

Medial moraines deposited by former glaciers and ice sheets are rare in Scotland. The most prominent example is the Sgriob na Caillich moraine, which consists of two to four parallel belts of angular quartzite boulders that extend northwestwards for over 3.5?km from the SW flank of Beinn an Oir on the Isle of Jura. The boulder belts extend to within 300?m of the present coastline, where they are truncated by a low bluff and raised marine terrace. The source of the moraine coincides with bedrock gullies and cliffs that represent the scars of former rock-slope failure(s), indicating that the moraine debris was sourced by one or more rockfalls or rockslides onto the ice surface after Beinn an Oir had emerged from the thinning ice cover as a nunatak. Exposure dating of boulders on the moraine indicate that it formed at 16.6?±?0.8?ka, consistent with the timing of ice-sheet retreat in this sector. The alignment of the moraine indicates ice-margin retreat to the SE; as regional ice-sheet retreat across the adjacent offshore shelf was to the NE, this anomaly implies that a residual icefield became stranded on Jura during ice-sheet retreat.     

Genetics and African Cattle Domestication

Whether cattle domestication occurred independently on the African continent is among the most controversial questions in the Holocene archaeology of northern Africa. One long-established scenario, based upon early archaeological evidence, suggested that Africa’s earliest cattle derived from several introductions from Southwest Asia through the Nile Valley, or via the Horn of Africa. Based upon archaeofaunal remains retrieved in the late twentieth century, other archaeologists argued that an independent domestication of the African aurochs gave rise to Africa’s earliest domestic cattle. Up to now, the genetic data have also been controversial. This paper reviews the archaeological evidence and the scope of debate, and then focuses on the recent contributions of genetic research to clarifying these issues.     

Tethered mobility and riparian resource exploitation among Neolithic hunters and herders in the Galana River basin,Kenyan coastal lowlands

Abstract

Human activity along the Galana River inside Tsavo National Park, Kenya extends from 6000 years BP until at least 1300 years BP. This time period in East Africa predates and includes the Pastoral Neolithic – geographically and temporally linked early cattle-herding cultures comprised of autonomous communities with loose cultural connections to one another. Data from some sites located in the Great Rift Valley, Lake Victoria Basin and Central Kenyan Highlands indicate that after 3000 years BP, residential mobility patterns increased and pastoralists adopted a strong dependence on maintaining and culling herds of domesticated animals. This pattern is not borne out in Tsavo, where artefact analyses indicate that people had restricted mobility and relied primarily on exploitation of an endoaquatic resource base. This study hypothesises that subdecadal periodicity in El Niño/Southern Oscillation index (ENSO) along with a general trend toward aridification of East African landscapes provided the environmental backdrop for a subsistence regime focused primarily within riparian environments of the Coastal Lowlands region.     

The Scandinavian reindeer (Rangifer tarandus L.) after the last glacial maximum: time,seasonality and human exploitation

Antlers and bones of reindeer (Rangifer tarandus L.) are the most frequently found vertebrate remains from the Late Glacial deposits of Southern Scandinavia. The Danish collection now consists of more than 350 specimens and of these 47 have been radiocarbon dated extending the range of occurrence in the area with ca. 1300 ¹⁴C yr. Thus the first occurrence is pushed back to ca. 12?500 ¹⁴C yr BP (late Bølling chronozone) while the youngest date lies at ca. 9200 ¹⁴C yr BP (late Preboreal chronozone) establishing that the reindeer survives well into the Holocene. The seasonal dates of the reindeer indicate for the first human occupation (the Havelte group from the Bølling period) a summer, autumn and early winter occupation, with reindeer, as well as man, apparently being absent during the coldest winter months. Finally, it is shown that Southern Scandinavia acted as a calving area throughout the Late Glacial and Early Holocene thus discrediting the North–South model of reindeer groups moving from a wintering area in Southern Scandinavia to a calving area in the foothills of the North European plain.     

Human refugia in Australia during the Last Glacial Maximum and Terminal Pleistocene: a geospatial analysis of the 25–12 ka Australian archaeological record

A number of models, developed primarily in the 1980s, propose that Aboriginal Australian populations contracted to refugia – well-watered ranges and major riverine systems – in response to climatic instability, most notably around the Last Glacial Maximum (LGM) (∼23–18 ka). We evaluate these models using a comprehensive continent-wide dataset of archaeological radiocarbon ages and geospatial techniques. Calibrated median radiocarbon ages are allocated to over-lapping time slices, and then K-means cluster analysis and cluster centroid and point dispersal pattern analysis are used to define Minimum Bounding Rectangles (MBR) representing human demographic patterns. Exploring data between 25 and 12 ka, we find a refugia-type hunter-gatherer response during the LGM (∼23–18 ka) and again during the Antarctic Cold Reversal (ACR) (∼14.5–12.5 ka), with expansion in the intervening period. Several refugia persist between 25 and 12 ka, including (by Interim Biogeographic Regionalisation for Australia areas) Gulf Plains/Einasleigh Uplands, Brigalow Belt South, Murray Darling Depression, and Tasmanian Central Highlands. Others appear sporadically through the same period. These include South Eastern Highlands, NSW South Western Slopes, Sydney Basin, Warren, Murchison, Gascoyne, Central and Northern Kimberley, Ord Victoria Plain, Arnhem Plateau, MacDonnell Ranges and Central Ranges. The Pilbara may also have been a refugium during the LGM, but geospatial results are problematic for this region. Areas devoid of human activity (‘barriers’) include the main desert regions, especially in the south and west of the continent, although some of these may be the result of an absence of archaeological fieldwork. Point dispersal pattern analysis indicates a reduction in occupied territory of nearly 80% during the LGM. A reduction of close to 50% was also evident during the ACR. A large number of the refugia were in close proximity to glaciated areas during the LGM, and probably benefitted from increased summer snowmelt along the major river systems. The remaining refugia are likely the result of a range of local environmental and resource factors. We identify areas for future research, including a focus on regional studies to determine possible cryptic or idiosyncratic refugia emerging in phlyogeographic studies.     

Testing the ‘Laacher See hypothesis’: a health hazard perspective

It has recently been suggested that the Laacher See volcanic eruption, which occurred around 13,000 years ago, initiated significant demographic fluctuations along the northern periphery of Late Glacial human settlement and that these led to a number of material culture transformations. The origins of the Southern Scandinavian Bromme culture and the northeastern European Perstunian culture as well as the temporary abandonment of Central European regions have been linked to this eruption. However, it remains unclear precisely which aspects of the eruption stimulated Late Glacial foragers to abandon their traditional ways of life. Paradoxically, the culture–historical impact of the eruption appears greater further away from the eruptive centre. Here, we investigate one potential middle-range link between the Laacher See eruption and Late Glacial fauna and foragers: tephra as a health hazard. We use laser-diffraction particle-size analysis to quantitatively investigate tephra from one site with a secure Late Glacial archaeological deposit. In addition, we use values previously reported in the literature and a predictive model to calculate the hazard potential along a transect of two of the three major Laacher See tephra fans. Our results show that the Laacher See tephra may have posed a potential health hazard and that its hazard potential may have increased with distance from the vent. To our knowledge this is the only study that attempts to quantify the changing grain-size composition of tephra fall-out longitudinally in this way, at least with regard to a prehistoric eruption. We close by discussing, more speculatively, other possible health-pertinent effects of the Laacher See eruption and suggest ways in which future work can further evaluate the impact of this eruption on Late Glacial populations.