Research Online at MacEwan :: Browsing by Author "Furze, Mark F.A."

Browsing by Author "Furze, Mark F.A."

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11,000 yrs of environmental change in the Northwest Passage; a multiproxy core record from central Parry Channel, Canadian High Arctic
(2013) Pieńkowski, Anna J.; England, John H.; Furze, Mark F.A.; Blasco, Steve; Mudie, Peta J.; MacLean, Brian
a rare paleoenvironmental archive from the understudied west-central Canadian Arctic Archipelago. Lithological, biogeochemical, and microfossil (dinoflagellate cysts, non-pollen palynomorphs, benthic and planktonic foraminifera) characteristics, in combination with a chronostratigraphy based on seventeen radiocarbon dates, show seven prominent paleoenvironmental episodes since the end of the last regional glaciation. The basal diamict (Zone I) records decoupling of previously grounded glacial ice, followed by ice-proximal conditions (Zone IIa) commencing at ~ 10.8 cal ka BP (age-depth model extrapolation). After an interval of pervasive sea-ice (Zone IIb), ice-distal conditions are established (Zone IIc). Although sparse microfossils are present in glaciomarine sediments (Zone II), noticeable biological activity with heightened abundances and diversities across all groups begins in the postglacial Zone III (10.3–10.0 cal ka BP) when planktonic foraminifera (Neogloboquadrina pachyderma) appear. As planktonics are excluded from the study area today (due to shallow inter-channel sills), this likely signals the inflow of relatively warm and saline Atlantic-derived Arctic Intermediate Water below 250 m, presumably facilitated by glacio-isostatically enhanced deglacial water depths. The subsequent Zone IV (10.0–7.0 cal ka BP), characterized by heightened biological productivity in both plankton and benthos and reduced seasonal sea-ice cover, may correspond to a previously proposed Holocene Thermal Maximum. This apparent amelioration ends by the mid Holocene (Zone V; 7.0–5.7 cal ka BP) when Arctic Intermediate Water is excluded from the study area and water depths approach modern values. High-Arctic conditions with seasonal sea-ice cover, a circulation dominated by Arctic Ocean Surface Water, and microfossil assemblages similar to modern are found from ~ 5.7 cal ka BP onwards (Zones VI–VII). As only minor environmental fluctuations are apparent during the late Holocene, shorter-term climatic episodes (e.g. Little Ice Age) are not recognized in this record.
A critical review of the glaciomarine model for Irish Sea deglaciation; evidence from southern Britain, the Celtic shelf and adjacent continental slope
(2001) Scourse, James D.; Furze, Mark F.A.
In support of their ‘glaciomarine’ model for the deglaciation of the Irish Sea basin, Eyles and McCabe cited the occurrence of distal glaciomarine mud drapes onshore in the Isles of Scilly and North Devon, and of arctic beach-face gravels and sands around the shores of the Celtic Sea. Glacial and sea-level data from the southern part of the Irish Sea in the terminal zone of the ice stream and the adjacent continental slope are reviewed here to test this aspect of the model. The suggestion that the glacial sequences of both the Isles of Scilly and Fremington in North Devon are glaciomarine mud drapes is rejected. An actively calving tidewater margin only occurred early in the deglacial sequence close to the terminal zone in the south-central Celtic Sea. Relative sea-levels were lower, and therefore glacio-isostatic depression less, than envisaged in the glaciomarine model. Geochronological, sedimentological and biostratigraphical data indicate that the raised beach sequences around the shores of the Celtic Sea and English Channel were deposited at, or during regression soon after, interglacial eustatic highstands. Evidence for ice-rafting at a time of high relative sea-levels is restricted to a phase(s) earlier than the Late Devensian. These data indicate that the raised beach sequences have no bearing on the style of Irish Sea deglaciation.
Arctic sea ice reconstruction for the past 500 years using palaeo-based proxies: a case study of PIP25 biomarker
(2015) Gill, Navpreet; Furze, Mark F.A.; Mugo, Samuel; Pieńkowski, Anna J.
To deduce paleoclimatic changes attributable to variability in the sea ice, a long-term record of sea-ice is required, beyond the time period covered by direct instrumental monitoring. A recent proxy for Arctic Ocean sea-ice has been developed based on the analysis of an isomer of C25, also known as IP25 (Ice proxy with 25 carbo atoms). In addition, other phytoplankton - derive biomarkers such as brassicasterol (Phytoplankton marker - IP25 index; PIP25) are employed to confirm sea ice change deductions for the past 500 years.
Atlantic water inflow in the early Holocene Northwest Passage marked by planktonic foraminifera (Neogloboquadrina pachyderma)
(2015) Pieńkowski, Anna J.; Cage, Alix; Furze, Mark F.A.; Figueiredo Martins, Ana Sílvia de; England, John H.; McLean, Brian; Blasco, Steve
Four marine piston cores from the central Canadian Arctic Archipelago (CAA), investigated for sedimentology, micropalaeontology, and biogeochemistry (52 AMS radiocarbon dates), uniformly show the prominent early Holocene (˜10 cal ka BP) appearance of planktonic foraminifera immediately following deglaciation.
Comment on "Multi-proxy record of postglacial environmental change, south-central Melville Island, Northwest Territories, Canada" by Peros et al., 2010, Quaternary Research 73, 247-258
(2010) Furze, Mark F.A.; England, John H.
The new multi-proxy paleoenvironmental record recently reported from Lake BC01, on south-central Melville Island, western Canadian Arctic Archipelago (CAA), constitutes an important contribution to the regional literature (Peros et al., 2010). This continuous record, spanning the last ~12,000 cal yr BP, provides an important link between the late glacial and postglacial vegetation history, and related paleoclimatic conditions deciphered from them. Although we welcome these new perspectives, the summary of the late Quaternary glacial geology that the paper also addresses contains problematic interpretations of recently published regional revisions (England et al., 2006, 2009) that warrant clarification.
Comment: Holocene palaeoceanographic changes in Barrow Strait, Canadian Arctic: foraminiferal evidence
(2010) Furze, Mark F.A.; Pieńkowski, Anna J.; England, John H.; Gregory, Thomas R.; Smart, Christopher W.; Hart, Malcolm B.; Masse, Guillaume; Vare, Lindsay L.; Belt, Simon T.
Comment on the article Holocene palaeoceanographic changes in Barrow Strait, Canadian Arctic: foraminiferal evidence.
Corrigendum to “Revision of the NW Laurentide Ice Sheet: implications for paleoclimatic, the northeast extremity of Beringia, and Arctic Ocean sedimentation” [Quat. Sci. Rev. 28 (2009) 1573–1596]
(2010) England, John H.; Furze, Mark F.A.; Doupe, Jonathan P.
For the past half-century, reconstructions of North American ice cover during the Last Glacial Maximum have shown ice-free land distal to the Laurentide Ice Sheet, primarily on Melville and Banks islands in the western Canadian Arctic Archipelago. Both islands reputedly preserve at the surface multiple Laurentide till sheets, together with associated marine and lacustrine deposits, recording as many as three pre-Late Wisconsinan glaciations. The northwest corner of Banks Island was purportedly never glaciated and is trimmed by the oldest and most extensive glaciation (Banks Glaciation) considered to be of Matuyama age (>780 ka BP). Inside the limit of Banks Glaciation, younger till sheets are ascribed to the Thomsen Glaciation (pre-Sangamonian) and the Amundsen Glaciation (Early Wisconsinan Stade). The view that the western Canadian Arctic Archipelago remained largely ice-free during the Late Wisconsinan is reinforced by a recent report of two woolly mammoth fragments collected on Banks and Melville islands, both dated to w22 ka BP. These dates imply that these islands constitute the northeast extremity of Beringia. A fundamental revision of this model is now warranted based on widespread fieldwork across the adjacent coastlines of Banks and Melville islands, including new dating of glacial and marine landforms and sediments. On Dundas Peninsula, southern Melville Island, AMS 14C dates on ice-transported marine molluscs within the most extensive Laurentide till yield ages of 25–49 ka BP. These dates require that Late Wisconsinan ice advanced northwestward from Visount Melville Sound, excavating fauna spanning Marine Isotope Stage 3. Laurentide ice that crossed Dundas Peninsula (300 m asl) coalesced with Melville Island ice occupying Liddon Gulf. Coalescent Laurentide and Melville ice continued to advance westward through M’Clure Strait depositing granite erratics at 235 m asl that require grounded ice in M’Clure Strait, as do streamlined bedforms on the channel floor. Deglaciation is recorded by widespread meltwater channels that show both the initial separation of Laurentide and Melvile ice, and the successive retreat of Laurentide ice southward across Dundas Peninsula into Viscount Melville Sound. Sedimentation from these channels deposited deltas marking deglacial marine limit. Forty dates on shells collected from associated glaciomarine rhythmites record nearsynchronous ice retreat from M’Clure Strait and Dundas Peninsula to north-central Victoria Island w11.5 ka BP. Along the adjacent coast of Banks Island, deglacial shorelines also record the retreat of Laurentide ice both eastward through M’Clure Strait and southward into the island’s interior. The elevation and age (w11.5 ka BP) of deglacial marine limit there is fully compatible with the record of ice retreat on Melville Island. The last retreat of ice from Mercy Bay (northern Banks Island), previously assigned to northward retreat into M’Clure Strait during the Early Wisconsinan, is contradicted by geomorphic evidence for southward retreat into the island’s interior during the Late Wisconsinan. This revision of the pattern and age of ice retreat across northern Banks Island results in a significant simplification of the previous Quaternary model. Our observations support the amalgamation of multiple till sheets – previously assigned to at least three pre-Late Wisconsinan glaciations – into the Late Wisconsinan. This revision also removes their formally named marine transgressions and proglacial lakes for which evidence is lacking. Erratics were also widely observed armouring meltwater channels originating on the previously proposed never-glaciated landscape. An extensive Late Wisconsinan Laurentide Ice Sheet across the western Canadian Arctic is compatible with similar evidence for extensive Laurentide ice entering the Richardson Mountains (Yukon) farther south and with the Innuitian Ice Sheet to the north. Widespread Late Wisconsinan ice, in a region previously thought to be too arid to sustain it, has important implications for paleoclimate, ice sheet modelling, Arctic Ocean ice and sediment delivery, and clarifying the northeast limit of Beringia. Unfortunately, when this paper was originally published there were missing data in Table 2, i.e. eight Reservoir-corrected dates were not included. The correct Table 2 is printed on the following pages.
Deglacial to postglacial palaeoenvironments of the Celtic Sea; lacustrine conditions versus a continuous marine sequence
(2014) Furze, Mark F.A.; Scourse, James D.; Pieńkowski, Anna J.; Marret, Fabienne; Hobbs, William O.; Carter, Rosemary A.; Long, Brian T.
Recent work on the last glaciation of the British Isles has led to an improved understanding of the nature and timing of the retreat of the British−Irish Ice Sheet (BIIS) from its southern maximum (Isles of Scilly), northwards into the Celtic and Irish seas. However, the nature of the deglacial environments across the Celtic Sea shelf, the extent of subaerial exposure and the existence (or otherwise) of a contiguous terrestrial linkage between Britain and Ireland following ice retreat remains ambiguous. Multiproxy research, based on analysis of 12 BGS vibrocores from the Celtic Deep Basin (CDB), seeks to address these issues. CDB cores exhibit a shell-rich upward fining sequence of Holocene marine sand above an erosional contact cut in laminated muds with infrequent lonestones. Molluscs, in situ Foraminifera and marine diatoms are absent from the basal muds, but rare damaged freshwater diatoms and foraminiferal linings occur. Dinoflagellate cysts and other non-pollen palynomorphs evidence diverse, environmentally incompatible floras with temperate, boreal and Arctic glaciomarine taxa co-occurring. Such multiproxy records can be interpreted as representing a retreating ice margin, with reworking of marine sediments into a lacustrine basin. Equally, the same record may be interpreted as recording similar conditions within a semi-enclosed marine embayment dominated by meltwater export and deposition of reworked microfossils. As assemblages from these cores contrast markedly with proven glaciomarine sequences from outside the CDB, a glaciolacustrine interpretation is favoured for the laminated sequence, truncated by a Late Weichselian transgressive sequence fining upwards into fully marine conditions. Reworked rare intertidal molluscs from immediately above the regional unconformity provide a minimum date c. 13.9 cal. ka BP for commencement of widespread marine erosion. Although suggestive of glaciolacustrine conditions, the exact nature and timing of laminated sediment deposition within the CDB, and the implications this has on (pen)insularity of Ireland following deglaciation, remain elusive.
Foraminifera: a tool for elucidating past and recent climate change in marine Arctic Canada
(2017) Thiessen, Rabecca; Pieńkowski, Anna J.; Furze, Mark F.A.; Cage, Alix; Caouette, Alexandre; Coates, Sina
Over the past five decades, polar regions such as the Canadian Arctic Archipelago (CAA) have experienced pronounced changes associated with recent climate warming, such as sea ice decline (ACIA, 2005; IPCC, 2007). Such relatively recent and open-ended environmental shifts have motivated research regarding past climate variability to understand how polar marine environments responded to previous high-magnitude changes such as glacial to interglacial transitions. MacEwan University's RAPIDE (Researching Arctic Palaeoceanographic Indicators of Deglacial Environments) program seeks to apply multiple sedimentological, stratigraphic, and micropalaeontological approaches to elucidate the timing and style of marine-based deglaciation and subsequent oceanographic evolution through the CAA.
Iceshelf instability and the collapsing NW margin of the Laurentide Ice Sheet: core evidence from Viscount Melville Sound, Arctic Canada
(2013) Furze, Mark F.A.; Pieńkowski, Anna J.; England, John H.; Esteves, Mariana da Silveira Ramos; Bennett, Robbie; Krywko, Jack; Glembiski, Danna; McLean, Brian; Blasco, Steve
Recent work in the western Canadian Arctic Archipelago has seen a dramatic re-evaluation of the timing and extent of Late Wisconsinan glaciation by a primarily cold-based Laurentide Ice sheet. This has included the occupation by ice of formerly-considered ice free terrain and the extension of grounded ice from the main channels of the Northwest Passage, westwards onto the Beaufort Sea continental shelf. Nonetheless, while the pattern of ice extent and initial retreat is now well constrained, significant questions remain regarding the main phase of ice retreat southeastwards onto mainland Canada and the stability of the retreating margin in response to ameliorating climate and sea-level change.
Late Holocene environmental conditions in Coronation Gulf, southwestern Canadian Arctic Archipelago; evidence from dinoflagellate cysts, other non-pollen palynomorphs, and pollen
(2011) Pieńkowski, Anna J.; Mudie, Peta J.; England, John H.; Smith, John N.; Furze, Mark F.A.
Boxcore 99LSSL-001 (68.095°?N, 114.186° W; 211?m water depth) from Coronation Gulf represents the first decadal-scale marine palynology and late Holocene sediment record for the southwestern part of the Northwest Passage. The record was studied for organic-walled microfossils (dinoflagellate cysts, non-pollen palynomorphs), pollen, terrestrial spores, and sediment characteristics. 210Pb, 137Cs, and three accelerator mass spectrometry 14C dates constrain the chronology. Three prominent palaeoenvironmental zones were identified. During the interval AD 1470–1680 (Zone I), the climate was warmer and wetter than at present, and environmental conditions were more favourable to biological activity and northward boreal forest migration, with reduced sea-ice and a longer open-water (growing) season. The interval AD 1680–1940 (Zone II) records sea-ice increase, and generally cool, polar conditions during the Little Ice Age. During AD 1940–2000 (Zone III), organic microfossils indicate an extended open-water season and decreased sea-ice, with suggested amelioration surpassing that of Zone I. Although more marine studies are needed to place this record into an appropriate context, the succession from ameliorated (Zone I) to cooler, sea-ice influenced conditions (Zone II) and finally to 20th-century warming (Zone III) corresponds well with several terrestrial climatic records from the neighbouring mainland and Victoria Island, and with lower-resolution marine records to the west.
Late Quaternary marine records from High Arctic Canada: problems, solutions, and multiproxy perspectives
(2013) Pieńkowski, Anna J.; Furze, Mark F.A.; England, John H.; MacLean, Brian; Von Prause, Markus; Blasco, Steve
The Canadian Arctic Archipelago (= CAA) constitutes a significant geographic region within the Arctic Ocean Basin, influencing its oceanography, biology, ecology, and climate. Yet comparatively little is known about the long-term (post-Late Wisconsinan) environmental history of the marine channels of this region (the “Northwest Passage” = NWP). New marine data emerging from the central CAA extending back to regional deglaciation highlight the potential of multiproxy approaches in high-latitude settings.
Low-stand lakes and garbled gastropods: the problems of interpreting the enigmatic deglacial and postglacial environments of the Celtic Sea Shelf
(2012) Furze, Mark F.A.
Recent work on the last glaciation of the British Isles has lead to an improved understanding of the nature and timing of the retreat of the British-Irish Ice sheet (BIIS) from its southern maximum (Isles of Scilly).
Most northerly observation of a grizzly bear (ursus arctos) in Canada: photographic and DNA evidence from Melville Island, Northwest Territories
(2007) Doupe, Jonathan P.; England, John H.; Furze, Mark F.A.; Paetkau, D.
During geological studies in 2003 and 2004 on Melville Island, Northwest Territories, Canada, field parties photographed and gathered genetic information on one or more grizzly bears (Ursus arctos). To our knowledge, these data constitute the most northerly observations made of this species in North America. The DNA of a hair sample collected on Melville Island in 2004 is genetically indistinguishable from DNA collected from a population of grizzly bears around Paulatuk, Northwest Territories, along the northern mainland coast. It is also distinct from the DNA of the Viscount Melville polar bear (Ursus maritimus) population. Our evidence and review suggest that, at a minimum, transient grizzly bears are now regular visitors to the Canadian Arctic Archipelago. More research will be required to understand the significance of these observations, but a small viable population of grizzly bears may now be using areas in or around Melville Island.
New cetacean Delta R values for Arctic North America and their implications for marine-mammal-based palaeoenvironmental reconstructions
(2014) Furze, Mark F.A.; Pieńkowski, Anna J.; Coulthard, Roy D.
Radiocarbon-dated marine mammal remains from emergent Arctic coastlines have frequently been used to reconstruct Holocene sea-ice histories. The use of such reconstructions has hitherto been complicated by uncertain marine reservoir corrections precluding meaningful intercomparisons with data reported in calibrated or sidereal years. Based on an exhaustive compilation of previously published marine mammal radiocarbon dates (both live-harvested materials and subfossils) from the Canadian Arctic Archipelago (CAA), new, statistically-derived delta (super 13) C and Delta R values are provided. Average delta (super 13) C values are: -16.1 + or - 1.1 ppm (bone collagen; n = 193) for bowhead (Balaena mysticetus); -14.4 + or - 0.5 ppm (n = 44; dentine) for beluga (Delphinapterus leucas); -14.8 + or - 1.9 ppm (teeth and tusks; n = 18) and -18.0 + or - 4.7 ppm (n = 9; bone collagen) for walrus (Odobenus rosmarus). Delta R values are 170 + or - 95 (super 14) C years for bowhead (n = 23) and 240 + or - 60 (super 14) C years for beluga (n = 12). Scarce data preclude calculation of meaningful, statistically robust walrus Delta R. Using the new Delta R values, an expanded and revised database of calibrated bowhead dates (651 dates; many used in previous CAA sea-ice reconstructions) shows pronounced late Quaternary spatio-temporal fluctuations in bone abundance. Though broadly resembling earlier bowhead subfossil frequency data, analysis of the new expanded database suggests early- and mid-Holocene increases in whale abundance to be of longer duration and lower amplitude than previously considered. A more even and persistent spread of infrequent low-abundance remains during "whale free" intervals is also seen. The dominance of three eastern regions (Prince Regent Inlet & Gulf of Boothia; Admiralty Inlet; Berlinguet Inlet/Bernier Bay) in the CAA data, collectively contributing up to 88% of all subfossil remains in the mid-Holocene, is notable. An analysis of calibrated regional sea-level index points suggests that severance of the Admiralty Inlet-Gulf of Boothia marine channel due to isostatically-driven regression may have played a significant role in enhanced whale mortality during this interval. Comparisons between the newly calibrated bowhead data and other regional sea-ice proxy data further highlight spatial and temporal discrepancies, potentially due to regional asynchronicities and variable sensitivities in proxy response to climate and oceanographic forcing. However, the limited number of deglacial-postglacial marine records continues to hamper extensive intercomparisons between marine mammal and other proxy datasets. Nevertheless, an examination of assumptions inherent in linking bowhead subfossil frequencies, population densities, and sea-ice thickness and distribution, shows that such relationships are highly complex. Factors such as broad sea-ice preferences, variable mortality rates and causes, long distance carcass transport, variable coastline and basin/channel geometries, and changing emergence rates all complicate the correlation of whale bone abundance to sea-ice histories.
New evidence for a grounded Irish Sea glaciation of the Isles of Scilly, UK
(2006) Hiemstra, John F.; Evans, David J. A.; Scourse, James D.; McCarroll, Danny; Furze, Mark F.A.; Rhodes, Ed
New geomorphological and sedimentological data support previously published reconstructions of an Irish Sea Glacier advance as far south as the northern shores of the Isles of Scilly in the Celtic Sea (49°58′N). Offshore, boulder-covered bars with cores of diamicton are interpreted as moraines, which together with onshore moraine ridges and trimlines mark the maximal extent of the Irish Sea Glacier. At Bread and Cheese Cove, St. Martin's, a heterogeneous sediment unit, wedged between periglacial gelifluctates, is interpreted as a mixture of glacitectonized and cannibalized glacilacustrine and marine deposits as well as primary subglacial tills. Macrofabric signatures reflect a subglacial origin, but the whole unit has been subject to down-slope mass movement. Micromorphological analysis indicates highly variable response to deformation and glacitectonism, with most features relating to ductile behaviour and wet deformation. The characteristics suggest deposition during a short-lived advance of the Irish Sea Glacier over pre-existing marine and contemporaneous proglacial lacustrine sediments. Once blocks of stratified sediment and diamicton had been driven onshore, they were subject to paraglacial remobilization, resulting at most locations in complete disaggregation. The distribution of re-worked glacigenic sediments coincides with the glacial limits inferred from the geomorphological evidence.
New evidence from the western Canadian Arctic Archipelago for the resubmergence of Bering Strait
(2008) England, John H.; Furze, Mark F.A.
Widespread molluscan samples were collected from raised marine sediments to date the last retreat of the NW Laurentide Ice Sheet from the western Canadian Arctic Archipelago. At the head of Mercy Bay, northern Banks Island, deglacial mud at the modern coast contains Hiatella arctica and Portlandia arctica bivalves, as well as Cyrtodaria kurriana, previously unreported for this area. Multiple H. arctica and C. kurriana valves from this site yield a mean age of 11.5 14C ka BP (with 740 yr marine reservoir correction). The occurrence of C. kurriana, a low Arctic taxon, raises questions concerning its origin, because evidence is currently lacking for a molluscan refugium in the Arctic Ocean during the last glacial maximum. Elsewhere, the oldest late glacial age available on C. kurriana comes from the Laptev Sea where it is < 10.3 14C ka BP and attributed to a North Atlantic source. This is 2000 cal yr younger than the Mercy Bay samples reported here, making the Laptev Sea, ~ 3000 km to the west, an unlikely source. An alternate route from the North Atlantic into the Canadian Arctic Archipelago was precluded by coalescent Laurentide, Innuitian and Greenland ice east of Banks Island until ~ 10 14C ka BP. We conclude that the presence of C. kurriana on northern Banks Island records migration from the North Pacific. This requires the resubmergence of Bering Strait by 11.5 14C ka BP, extending previous age determinations on the reconnection of the Pacific and Arctic oceans by up to 1000 yr. This renewed ingress of Pacific water likely played an important role in re-establishing Arctic Ocean surface currents, including the evacuation of thick multi-year sea ice into the North Atlantic prior to the Younger Dryas geochron.
New marine ΔR values for Arctic Canada
(2010) Coulthard, Roy D.; Furze, Mark F.A.; Pieńkowski, Anna J.; Nixon, F. Chantel; England, John H.
For more than four decades, the reporting of 14C dates on marine molluscs from Arctic Canada has been notable for the lack of consistently applied marine reservoir corrections. We propose that the common approach of reporting Canadian Arctic marine 14C dates using presumed time-invariant reservoir corrections be abandoned in favour of calibration of 14C dates, using the current standard protocol. This approach best facilitates inter- and intra-regional correlation, and correlation with other geochronometers. In order to enable the consistent calibration of marine 14C dates from Arctic Canada, we analysed a 14C database of 108 marine mollusc samples collected live between 1894 and 1956, and determined regional reservoir offset values (ΔR) for eight oceanographically distinct regions. The following new ΔR values should be used for 14C calibration: NW Canadian Arctic Archipelago, 335 ± 85 yrs; Foxe Basin, 310 ± 90 yrs; NE Baffin Island, 220 ± 20 yrs; SE Baffin Island, 150 ± 60 yrs; Hudson Strait, 65 ± 60 yrs; Ungava Bay, 145 ± 95 yrs; Hudson Bay, 110 ± 65 yrs; and James Bay, 365 ± 115 yrs.
Pleistocene horse remains from NW Banks Island, Canadian Arctic Archipelago: implications for long-term landscape evolution
(2012) Furze, Mark F.A.
Recent work on NW Banks Island in the western Canadian Arctic Archipelago (CAA) has overturned the long-held paradigm that the area was never glaciated. However, occurrence of rare remains of mammoth from Banks and Melville islands (25.9-24.6 cal ka BP) suggests herb-rich tundra persisted for much of the Wisconsinan, and constrains the timing of glaciation.
Quaternary exposures in Whitsand Bay, south-east Cornwall: Downderry and Wiggle Cliff
(1999) Furze, Mark F.A.
The extensive Quaternary deposits, exposed in coastal sections in Whitsand Bay, South East Cornwall have received little attention in the recent literature. A thick sequence of raised littoral and possibly aeolian sands capped by a veneer of soliflucted head is described from the east of the Bay between Wiggle Cliff and Polhawn Cove, near Rame Head. Here, the great extent of unconsolidated in situ sands above a relict abrasion platform is considered to represent a transition from intertidal littoral to back-beach aeolian sediments associated with sea-level regression, probably during the late Ipswichian / early Devensian. Upper sand deposition is considered likely to have been penecontemporaneous with early solifluction. Further west at Downderry, relict littoral sands and gravels, now below the modern beach, occur beneath a stony clay unit. This clay is topped by an unusual stratified head sequence occurring beneath the more typical Main and Upper Head units. Clay horizons, interbedded with head, coarsen towards the top of the stratified sequence where they become dominantly loessic. The Upper Head, both here and at Wiggle Cliff, is characterised by the sporadic occurrence of small well-rounded local and exotic clasts apparently absent from the main soliflucted head. Both sites warrant further investigation, the aeolian sands and loessic horizons especially lending themselves to luminescence dating and so constraining further early Devensian sea-level fall and the onset of periglaciation in southwest Britain.

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