The sedimentology,stratigraphy and 14C dating of a turf‐banked solifluction lobe: evidence for Holocene slope instability at Okstindan,northern Norway

The stratigraphy of a trench excavated through a solifluction lobe lying at an altitude of 860 m a.s.l. on the eastern flank of the Okstindan mountains is described. Sedimentological evidence suggests that the movement was probably dominated by a flow process, with silty sands episodically bursting‐out through a thinly vegetated lobe front in the spring and early summer thaw phases, when pore‐water pressures were likely to be increased. A continuous buried soil extends for some 14 m. Fourteen new radiocarbon age estimates from thin‐slice samples of this buried soil and organic fractions derived from laboratory pre‐treatment procedures are discussed. These data indicate that the solifluction probably commenced in the mid‐Holocene and continued throughout the Neoglacial. The slope instability may be correlated tentatively with the record of glacial variations, shifts in tree lines and archaeological evidence, supporting a link with regional climatic deterioration. Copyright © 1999 John Wiley & Sons, Ltd.     

Holocene solifluction,climate variation and fire in a subarctic landscape at Pippokangas,Finnish Lapland,based on radiocarbon‐dated buried charcoal

A large number of radiocarbon dates from charcoal layers buried beneath stacked solifluction lobes at Pippokangas, in the northern boreal zone of Finnish Lapland, are used to reconstruct a Holocene history of solifluction. Although the site is surrounded by Scots pine forest, the solifluction lobes occur on the lower slopes of a kettle hole, the microclimate of which prevents the growth of trees. Samples from the upslope end of charcoal layers have enabled the recognition of four synchronous phases of solifluction lobe initiation: 7400–6700, 4200–3400, 2600–2100 and 1500–500 cal. yr BP. Rates of lobe advance are shown to be lobe‐dependent and age‐dependent: initially, average rates were commonly 0.14–0.19 cm yr^?1, later falling to 0.02–0.07 cm yr^?1 or less as the lobes approached the bottom of the slope. The absence of charcoal prior to 8000 cal. yr BP, together with single IRSL and TL dates, indicate a relatively stable early Holocene landscape. The onset of solifluction around 7400 cal. yr BP. appears to have followed the immigration of pine around the site, which increased the frequency of forest fires. Phases of solifluction activity seem to have been triggered by millennial‐scale variations in effective moisture (the climatic hypothesis), rather than episodic burning of the surface vegetation cover (the geoecological hypothesis), although climate may also have affected fire frequency and severity. Copyright © 2005 John Wiley & Sons, Ltd.     

Palaeoeskimo site burial by solifluction: Periglacial geoarchaeology of the tayara site (KbFk‐7), Qikirtaq Island,Nunavik (Canada)

The geoarchaeological study of the Palaeoeskimo Tayara site on Qikirtaq Island (Nunavik) has led to a better understanding of archaeological site formation in the arctic periglacial environment. The surrounding geomorphology (extra‐site) is characterized by fine‐grained, low plastic and leached postglacial glaciomarine sediments that have been reworked by sheet‐like solifluction. This process buried the northern part of the Tayara site with mean annual rates between 1.68 and 2.86 cm/yr over approximately 350 years (1330–980 yr B.P.). The physicochemical and mineralogical properties of the frost‐susceptible glaciomarine sediments may explain their susceptibility to solifluction. This process was probably enhanced by longer thawing periods or warmer/moister summer months that induced active layer thickening or rapid soil thawing. The dates we obtained in the downstream valley show that solifluction occurred during short warm periods in the Late Holocene between ca. 1500 and 1000 yr B.P., after 1000 yr B.P. (or after 500 yr B.P.) and recently (90–60 yr B.P.). Our data provide insights on the site factors and climate factors that govern site burial by solifluction. Solifluction promoted the preservation of the three superposed archaeological levels in the Tayara site; however, the waterlogging of the site related to solifluction also likely caused the subsequent abandonment of the site by the Palaeoeskimo people. © 2008 Wiley Periodicals, Inc.     

Geoarchaeology at Gilman Falls: An Archaic quarry and manufacturing site in central Maine,U.S.A.

Interdisciplinary investigations at the Milford Reservoir, central Maine, resulted in excavation and analysis of a Middle Archaic quarry and manufacturing site at Gilman Falls, dated to between 7300 and 6300 yr B.P. Lithological analysis indicates that the majority of the artifacts came from very local outcrops, providing low‐grade metamorphic rocks. Native Americans used a specialized technique to reduce the granofels and other rocks to long rods, artifacts commonly placed in local cemeteries. The Gilman Falls site was largely abandoned once these artifacts were no longer in vogue. Therefore, access to particular bedrock outcrops seems to have played an important role in site selection. Gilman Falls and other early to middle Holocene sites are preserved where bedrock sill dams ponded water that deposited fine sand. Early site sedimentation history is paralleled by a drainage change in the headwaters of the Penobscot River. Evidence for lower mid‐Holocene lake levels and a period of higher temperatures and lower precipitation may correlate with the sedimentation history. © 2001 John Wiley & Sons, Inc.     

Single‐Grain Luminescence Dating of Sediment Surrounding a Possible Late Pleistocene Artifact from the Wenas Creek Mammoth Site,Pacific Northwest,USA

Excavations at the Wenas Creek Mammoth Site yielded mammoth, bison, and two possible artifacts in a single colluvial stratum, with radiocarbon bone dates ∼17 ka. Eight infrared‐stimulated luminescence (IRSL) samples were collected to establish general ages of site strata, returning multi‐grain estimates consistent with stratigraphic integrity and the radiocarbon dates. Four additional IRSL samples were collected to estimate the depositional age of one artifact found in place. These produced a pooled total of 94 single‐grain estimates from near the artifact, 80% averaging 16.8 ± 0.9 ka, and 20% averaging 5.1 ± 0.5 ka. These results could be interpreted to demonstrate pre‐Clovis age artifact deposition consistent with the bone dates, or a mid to late Holocene intrusion into older deposits, possibly by bioturbation. The single‐grain IRSL dates do not provide proof of pre‐Clovis presence beyond reasonable doubt at this site, but do show that this technique is valuable in assessing the stratigraphic integrity needed for any such claim.     

Late Pleistocene sediments and environmental change at Plaza Creek,Falkland Islands,South Atlantic

Late Pleistocene organic-rich sediments exposed in coastal bluffs near the head of Plaza Creek, East Falkland, have yielded conventional and AMS ¹⁴C dates of between 36 and 28 ka BP, and possess a pollen spectrum dominated by grasses, indicating a vegetation assemblage similar to that of the present day. Although some sample dates are anomalous and contamination by non-contemporaneous carbon cannot be ruled out entirely, the age estimates are consistent with evidence and dates from Antarctica, South America and the amphi-North Atlantic for climate shifts to interstadial conditions at around that time. The organic-rich units are developed in and enclosed by deposits attributed to processes of periglacial mass wasting. Grain-size characteristics suggest that these sediments may have been emplaced by solifluction, shallow translational landsliding and surface wash in at least five mass-wasting episodes. Some of the mass-wasting sediments might correlate with solifluction deposits above and below a podsolic soil dated to 26 ka BP at San Carlos, East Falkland, and with periods of cirque and valley glaciation identified in the uplands of the Falkland Islands. The similarity between late Pleistocene interstadial, Holocene and present-day pollen assemblages, and the lack of vegetation change within these periods, is characteristic of most cool temperate Southern Ocean islands, and may reflect the lack of sensitivity of the vegetation to climate change and/or a lack of climate variability for the time intervals covered. © 1998 John Wiley & Sons, Ltd.     

Subsurface mapping of a buried paleoindian living surface,Lime Creek site,Nebraska, USA

Analysis of continuous core and drill cuttings from drill holes was compared and correlated to data obtained from bore hole geophysical logs to obtain subsurface stratigraphic information at the Lime Creek Paleoindian site, southern Nebraska. The analysis of these bore holes indicated that sedimentary layers and a significant buried soil horizon could be correlated throughout the preserved terrace fill at the site. Geophysical information obtained in well bores in 1993 was compared to lithologic and radiocarbon data from recent core holes and then integrated with archaeological profiles and artifacts collected between 1947 and 1950. A paleotopographic analysis of the soil horizon where the majority of the artifacts were discovered was then made. This ancient living surface was found to have developed on the banks of an abandoned channel, now deeply buried, that ran parallel to modern Lime Creek about 10,000 B.P. Paleoindian people likely camped on the banks of this channel, protected from cold northerly winds by a large bluff to the north of the site. © 2000 John Wiley & Sons, Inc.     

Geochronology and Geomorphology of the Pioneer Archaeological Site,Upper Snake River Plain,Idaho, USA

Pioneer is an open‐air, stratified, multicomponent archaeological site located in the upper Snake River Plain of southeastern Idaho, USA. Block excavations provided an opportunity to contribute to the Late Quaternary geomorphic history of the Big Lost River drainage and provide geochronological context of archaeological components at the site. The stratigraphic sequence is interpreted as reflecting multiple depositional episodes and five soil‐formation periods beginning pre‐7200 cal. yr B.P. and lasting to the historic period. The stratigraphic sequence contains an archaeological component dated to ∼3800 cal. yr B.P. and several other components post‐800 cal. yr B.P. Major site formation processes include fluvial deposition and erosion, pedogenesis (accumulation of secondary carbonates), and bioturbation. Periods of increased deposition at Pioneer and elsewhere along the Big Lost River are inferred to have occurred between ∼8400–6500 cal. yr B.P. and ∼2700–400 cal. yr B.P., potentially related to cooler/wetter episodes of the mid‐to‐late Holocene, including increased precipitation during the Medieval Climatic Anomaly (post‐750 cal. yr B.P.). There is also evidence of a high‐energy erosional event at ∼3800 cal. yr B.P. indicating a large middle Holocene flood. Pioneer provides an example of the archaeological and paleoclimatic value of studying alluvial buried soil stratigraphic sequences in arid environments.     

The accumulation of Stone Age lithic artifacts in rock fragment mulches in northern Ethiopia

Lithic artifacts buried in the soil profile may be transported to the surface during tillage‐induced kinetic sieving, differential erosion, or swell–shrink cycles of clays and become part of a rock fragment mulch. Archaeologically, these manifestations are recognized as surface scatters. Although artifacts at the soil surface are difficult to relate to the local stratigraphic context, surface assemblages may provide information on lithic industries and the archaeological significance of sparsely explored regions. Through in situ investigation of surface material in 60 1 × 1 m² plots in the Tembien district in the northern Ethiopian highlands, we show that rock fragment mulches can contain a significant number of lithic artifacts and we provide evidence for mid‐Pleistocene occupation of a site. Considering that severe rill and gully erosion may be a threat to the archaeological heritage and that well‐dated African Middle Stone Age sites are rare, we conclude that the region deserves more attention for archaeological research. © 2009 Wiley Periodicals, Inc.     

Calcrete formation and implications for buried archaeological deposits in the Mariana Islands,western Pacific

Calcrete zones of cemented sands are found repeatedly at beach sites in the Mariana Islands, western Pacific region, with mid‐ to late‐Holocene artifacts and midden sealed within and beneath these layers. Three site‐specific cases demonstrate that the cementation process of the calcareous sand material post‐dated the deposition of artifacts and midden. Archaeological efforts must be prepared for deep excavation through zones of cemented sand. Also, recovery of preserved ancient materials can proceed by excavating large hardened blocks and soaking in light (5%) acid. This knowledge about formation process and recovery technique may prove useful not only in the Mariana Islands but also more broadly in other regions with similar settings. © 2011 Wiley Periodicals, Inc.     

A magnetic susceptibility logger for archaeological application

Investigations of magnetic susceptibility have been used to (1) define sites, activity areas, features, buried soils, and cultural layers, (2) build and correlate stratigraphic sequences, and (3) understand site‐formation and postdepositional processes. Archaeologists are limited in these endeavors, however, by the instruments available for field studies of susceptibility. A prototype instrument developed for archaeological application logs volume magnetic susceptibility down a small‐diameter (ca. 2.2 cm) core‐hole made with a push‐tube corer. Measurements can be made rapidly, approximately 10 times faster than collecting samples either by coring or from an exposed section, to depths of 1.6 m below the surface. The prototype logger was field‐tested on a mid‐Holocene stratigraphic section in southeastern North Dakota where it clearly distinguished various soils and sediments, including a buried occupation layer. © 2001 John Wiley & Sons, Inc.     

Stratigraphy of Pleistocene glaciations in the St Elias Mountains,southwest Yukon,Canada

At least five Middle to Late Pleistocene advances of the northern Cordilleran Ice Sheet are preserved at Silver Creek, on the northeastern edge of the St Elias Mountains in southwest Yukon, Canada. Silver Creek is located 100 km up‐ice of the Marine Isotope Stage (MIS) 2 McConnell glacial limit of the St Elias lobe. This site contains ~3 km of nearly continuous lateral exposure of glacial and non‐glacial sediments, including multiple tills separated by thick gravel, loess and tilted lake beds. Infrared‐stimulated luminescence (IRSL) and AMS radiocarbon dating constrain the glacial deposits to MIS 2, 4, either MIS 6 or mid‐MIS 7, and two older Middle Pleistocene advances. This chronology and the tilt of the lake beds suggest Pleistocene uplift rates of up to 1.9 mm a^?1 along the Denali Fault since MIS 7. The non‐glacial sediment consists of sand, gravel, loess and organic beds from MIS 7, MIS 3 and the early Holocene. The MIS 3 deposits date to between 30–36 ¹⁴C ka BP, making Silver Creek one of the few well‐constrained MIS 3‐aged sites in Yukon. This confirms that ice receded close to modern limits in MIS 3. Pollen and macrofossil analyses show that a meadow‐tundra to steppe‐tundra mosaic with abundant herbs and forbs and few shrubs or trees, dominated the environment at this time. The stratigraphy at Silver Creek provides a palaeoclimatic record since at least MIS 8 and comprises the oldest direct record of Pleistocene glaciation in southwest Yukon.     

Two paleoecological histories spanning the period of human settlement in southeastern Brazil

The absence of human occupation sites in southeastern Brazil during the mid Holocene has been referred to as the 'Archaic Gap' (8970–1940 cal. a BP) and is predicted to have resulted from increased aridity. A ca. 14 000 cal. a pollen history from two well‐dated lake sediment cores located within the archeological district of Lagoa Santa, in the State of Minas Gerais, southeastern Brazil, was used to test this hypothesis. Our analyses indicated that the present cerrado and tropical semi‐deciduous forest mosaic persisted throughout the mid Holocene, until ca. 5500 cal. a BP, and the Lagoa Santa region did not experience especially dry conditions during the Holocene period. The early Holocene pollen spectra contained an assemblage of cold‐adapted taxa such as Podocarpus, Myrsine and Araucaria, co‐occurring with taxa from cerrado, e.g. Caryocar. A replacement of cold taxa by the modern cerrado–semi‐deciduous forest vegetation took place progressively, but appears to have been completed by the mid Holocene. No evidence of sustained drought was found in sedimentation or forest composition, nor any prolonged dry event in the study region. Holocene dryness as an explanation for the abandonment of Lagoa Santa region is not supported by the palynological analyses conducted in this study. Rather it is suggested that unpredictable climate may have underlain that abandonment. Copyright © 2012 John Wiley & Sons, Ltd.     

Geology of the dry creek site; a stratified early man site in Interior Alaska

The Dry Creek archeologic site contains a stratified record of late Pleistocene human occupation in central Alaska. Four archeologic components occur within a sequence of multiple loess and sand layers which together form a 2-m cap above weathered glacial outwash. The two oldest components appear to be of late Pleistocene age and occur with the bones of extinct game animals. Geologic mapping, stratigraphic correlations, radiocarbon dating, and sediment analyses indicate that the basal loess units formed part of a widespread blanket that was associated with an arctic steppe environment and with stream aggradation during waning phases of the last major glaciation of the Alaska Range. These basal loess beds contain artifacts for which radiocarbon dates and typologic correlations suggest a time range of perhaps 12,000–9000 yr ago. A long subsequent episode of cultural sterility was associated with waning loess deposition and development of a cryoturbated tundra soil above shallow permafrost. Sand deposition from local source areas predominated during the middle and late Holocene, and buried Subarctic Brown Soils indicate that a forest fringe developed on bluff-edge sand sheets along Dry Creek. The youngest archeologic component, which is associated with the deepest forest soil, indicates intermittent human occupation of the site between about 4700 and 3400 ¹⁴C yr BP.     

Three-dimensional modelling of a Holocene tufa system in the Lathkill Valley, north Derbyshire, using ground-penetrating radar

Unlithified and partly lithified carbonate sequences are ideally suited to the application of ground‐penetrating radar (GPR), augmented by percussion augering and shallow seismic techniques, all tied to present‐day topography using global positioning system (GPS) methods. This methodology provides the first clear information on the distribution and geometry of lithofacies within buried tufa complexes. The approach has been applied to a thick succession of Holocene tufas filling a gorge site along a 3·5‐km length of the River Lathkill, north Derbyshire. Earlier studies have demonstrated the presence of up to 16 m of tufas and sapropels associated with two transverse tufa dams (barrages). These strata have been accumulating throughout the Holocene, although tufa developments at present are of minor extent. Internal tufa morphologies are recorded by GPR as ‘bright’, laterally continuous reflections for lithified, concretionary and lithoclast‐rich horizons. The ‘brightest’ reflectors occur within well‐cemented barrages and delineate core areas and prograding buttress zones. In contrast, unlithified lime muds and sapropels produce low‐contrast reflections. Lithostratigraphic control and depth calibration of the GPR profiles was provided by percussion augering at selected sites. Six distinct lithofacies and four secondary barrages are identified in the study. Constructional and destructional events can be identified and correlated within the GPR profile network, and the internal growth morphologies of the barrages are apparent. GPR profiles also clearly define the evolution of the facies geometries. Three phases of tufa development can be recognized within the GPR data and greatly extend our understanding of Holocene tufa‐forming processes in valley sites: (a) Early Holocene barrage build‐ups but with limited paludal deposition; (b) Middle Holocene ponding and sapropel accumulation under ‘warm’ conditions; and (c) Late Holocene barrage termination and valley levelling, probably coincidental with anthropogenic activity. This type of multidisciplinary approach should be considered as an essential prerequisite to all biostratigraphic and geochemical studies of Holocene freshwater carbonate sites.     

Late Quaternary landscape history and geoarchaeology of two drainages on Black Mesa,northeastern Arizona,USA

Two approximately 5‐ to 6‐km drainage segments on Black Mesa preserve unusually complete sequences of late Quaternary alluvium and soils. Radiocarbon‐ and tree‐ring‐dated alluvial and soil stratigraphy suggests entrenched paleoarroyos were beginning to aggrade at about >24,260, 11,070, 9660, 8800, 7060, 3500, 2140, and 1870 ¹⁴C yr B.P. Using the quantity of sediment removal from post‐A.D. 1900 arroyos as analogue, at least 77–200% of total valley alluvium has been removed and replaced by younger sediments during an estimated 11 late Pleistocene and Holocene erosion epicycles. Given that most (59%) of the 150 recorded prehistoric sites in the two study areas occur on valley floors where only about 3% of surface alluvium predates Lolomai phase Basketmaker II occupation (˜1900–1600 yr B.P.), it may be inferred that pre‐Lolomai phase Basketmaker II sites which may have been located along washes have been removed or buried by fluvial erosion. Identification of five buried hearths in alluvial sections, including White Dog and Lolomai phase Basketmaker II sites (dating about 3500 and 1870 ¹⁴C yr B.P., respectively) and one possible Early Archaic site, supports this conclusion. © 2005 Wiley Periodicals, Inc.     

Holocene permafrost history and cryostratigraphy in the High‐Arctic Adventdalen Valley,central Svalbard

This paper presents the history and cryostratigraphy of the upper permafrost in the High‐Arctic Adventdalen Valley, central Svalbard. Nineteen frozen sediment cores, up to 10.7 m long, obtained at five periglacial landforms, were analysed for cryostructures, ice, carbon and solute contents, and grain‐size distribution, and were ¹⁴C‐ and OSL‐dated. Spatial variability in ice and carbon contents is closely related to the sedimentary history and mode of permafrost aggradation. In the valley bottom, saline epigenetic permafrost with pore ice down to depths of 10.7 m depth formed in deltaic sediments since the mid‐Holocene; cryopegs were encountered below 6 m. In the top 1 to 5 m, syngenetic and quasi‐syngenetic permafrost with microlenticular, lenticular, suspended and organic‐matrix cryostructures developed due to loess and alluvial sedimentation since the colder late Holocene, which resulted in the burial of organic material. At the transition between deltaic sediments and loess, massive ice bodies occurred. A pingo developed where the deltaic sediments reached the surface. On hillslopes, suspended cryostructure on solifluction sheets indicates quasi‐syngenetic permafrost aggradation; lobes, in contrast, were ice‐poor. Suspended cryostructure in eluvial deposits reflects epigenetic or quasi‐syngenetic permafrost formation on a weathered bedrock plateau. Landform‐scale spatial variations in ground ice and carbon relate to variations in slope, sedimentation rate, moisture conditions and stratigraphy. Although the study reveals close links between Holocene landscape evolution and permafrost history, our results emphasize a large uncertainty in using terrain surface indicators to infer ground‐ice contents and upscale from core to landform scale in mountainous permafrost landscapes.     

Flood frequencies reveal Holocene rapid climate changes (Lower Moulouya River,northeastern Morocco)

Current high‐resolution palaeoenvironmental records reveal short‐term Holocene coolings. One of these major Holocene rapid climate changes occurred between 3.2 and 2.7 cal. ka BP. The sensitivity of river systems vis‐à‐vis slight and short‐term Holocene climatic variations is a subject of controversy in the scientific community. In this paper, we present a 4.0 to 1.4 cal ka BP palaeoflood record from the Lower Moulouya River (northeastern Morocco) to demonstrate the high sensitivity of semiarid rivers in the southwestern Mediterranean towards Holocene environmental changes. The Lower Moulouya flood deposits are characterised by thick, well‐stratified, predominantly clayey to silty overbank fine sediments. These cohesive sediments show evidence of excellent preservation conditions against fluvial erosion and contain a continuous record of mid to late Holocene flood sequences. The Moulouya palaeoflood record can be interpreted in the context of regional and global high‐resolution proxy data, revealing a strong coupling with Holocene rapid climate changes. The centennial‐scale Moulouya palaeohydrological history will be discussed with palaeoenvironmental data from the same record (palaeomagnetics, sedimentary charcoal record, anthracological analyses, snail analyses) to generate new ideas about the mid to late Holocene hydrological cycle in the southwestern Mediterranean. The deduced features of pronounced Lower Moulouya flooding and the decreased fire recurrence during Holocene cooling remain somewhat inconsistent with the interpretation of other palaeohydrological and paleaoecological records from the southwestern Mediterranean. However, enhanced Lower Moulouya flood frequencies between 3.2 and 2.7 cal. ka BP agree with increased floodplain aggradation in other major river systems of Mediterranean North Africa. Copyright © 2009 John Wiley & Sons, Ltd.     

Shallow site archaeology: Artifact dispersal,stratigraphy, and radiocarbon dating at the Barger Gulch locality B Folsom Site,Middle Park,Colorado

Shallowly buried archaeological sites are particularly susceptible to surface and subsurface disturbance processes. Yet, because cultural deposition often operates on short time scales relative to geologic deposition, vertical artifact distributions can be used to clarify questions of site formation. In particular, patterns in artifact distributions that cannot be explained by occupation histories must be explained by natural processes that have affected sites. Buried only 10–50 cm beneath the ground surface for 10,450 ¹⁴C yr, the Folsom component at Barger Gulch Locality B (Middle Park, Colorado) exhibits many signs of post‐depositional disturbance. Through examination of variation in the vertical distribution of the artifact assemblage, we are able to establish that only a Folsom component is present. Using vertical artifact distributions, stratigraphy, and radiocarbon dating, we are able to reconstruct the series of events that have impacted the site. The Folsom occupation (˜10,450 ¹⁴C yr B.P.) was likely initially buried in a late‐Pleistocene eolian silt loam. Erosion brought the artifacts to rest on a deflation surface at some time prior to 9400 ¹⁴C yr B.P. A mollic epipedon formed in sediments that accumulated between 9400 and 7000 ¹⁴C yr B.P. Some time after 5200 ¹⁴C yr B.P., this soil was partially truncated, and artifacts that had previously dispersed upward created a secondary lag at its upper contact. This surface was buried again and artifact dispersal continued. © 2005 Wiley Periodicals, Inc.     

Holocene palaeoenvironmental reconstruction based on fossil beetle faunas from the Southern Altai region,north‐west China

We present here the results of the first‐ever Quaternary entomological research in China. The Halashazi Wetland, located in the southern Altai Mountain region in the northernmost part of Xinjiang Province, yielded Holocene insect fossils (mostly beetles) from two peat profiles. In total, 55 Coleoptera taxa were found, including 37 identified species. A new species, Helophorus sinoglacialis, was identified. The fauna is strongly northern Holarctic in character. The interval from 10 424 to 9705 cal a BP was probably a cold and wet period, and the study site was above the treeline. From 9665 to 9500 cal a BP it was probably warmer and drier, and treeline moved to higher elevations. Following a depositional hiatus, mid‐Holocene (5400–4400 cal a BP ) insect assemblages represent cold conditions with the site above the treeline. The exception was a brief warming around 5450 cal a BP , when bark beetle evidence suggests that the treeline moved to a higher elevation. Of the 37 identified beetle species from the Halashazi site, 34 (92%) have modern records in Siberia. The Altai Mountains probably served as a dispersal corridor between the Siberian arctic and alpine regions of northern China. Copyright © 2019 John Wiley & Sons, Ltd.