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An understanding of the growth and demise of ice sheets over North America is essential to inform future climate models. One poorly studied subject is the glacial dynamics during interstadial Marine Isotope Stage (MIS) 3 (57–29 ka). To better constrain the southern margin of the Laurentide Ice Sheet during this time period, we re-examined a stratigraphic sequence in southeast Manitoba, Canada, and provide robust evidence for advance and retreat of ice. Around 46.6 ± 5.1 ka (1σ error), fluvial sands were deposited under similar precipitation and significantly cooler summer temperatures than present-day. Ice then advanced south over the area, before retreating once again and a return to boreal forest and grassland conditions. The area was then covered by proglacial Lake Vita, dammed by ice to the north. Geochronology constraints indicate Lake Vita existed from ca. 44.3 ± 3.6 to 30.4 ± 2.3 ka (1σ error), although gaps in the optical and finite radiocarbon ages suggest either a lack of data or plausible temporary ice-margin advances during this time period. Ice covering most of Manitoba during MIS 3 is in line with global δ18O records, and glacially influenced sediment deposition in the Mississippi River basin. [ABSTRACT FROM AUTHOR]

Laurentide Ice Sheet (LIS) reconstructions beyond the last glacial maximum (LGM) are difficult due to the incomplete stratigraphic record that has largely been eroded by the most recent glaciation. The Hudson Bay Lowland (HBL) is a key region to understanding the long-term evolution of the LIS, as it contains an extensive pre-LGM stratigraphic record of glacial and nonglacial events. This study uses a hybrid lithostratigraphy–allostratigraphy approach to decipher the stratigraphic record in the Kaskattama highland region of the western HBL, Manitoba, Canada. We identify five glacial (till) units and three nonglacial (sorted sediment) units that were deposited during at least three glacial–interglacial cycles, which are constrained by radiocarbon and optical ages. The provenance of till units is identified using clast-lithology and detrital hornblende 40Ar/39Ar ages and supported by matrix geochemistry. The new stratigraphic framework for this western HBL region indicates that the ice emanating from the Quebec–Labrador dome advanced into the region at the start of the last two glaciations, suggesting accelerated early growth of the Quebec–Labrador dome relative to the Keewatin Dome. [ABSTRACT FROM AUTHOR]

Regional subsurface mapping of glacial depositional systems preserved in buried bedrock paleovalleys, and quantitative analysis of new LiDAR imagery of surface glacial landforms using machine learning techniques, when combined, are powerful tools for assessing the dynamics of the Laurentide Ice Sheet (LIS) during the last (Wisconsinan) glaciation in southern Ontario. While age dating of deposits preserved below Last Glacial Maximum tills (LGM: marine isotope stage (MIS) 2 < c.24 000 years B.P. (ybp)) is still sparse, newly available sedimentological data derived by cored drilling, combined with legacy outcrop data, identify thick (100 m+) successions of glaciolacustrine sediments and a lack of till(s), indicating that the ice sheet margin did not extend beyond the Niagara Escarpment at the western end of Lake Ontario, during the earliest phases of the glaciation (MIS 4) or the ensuing mid-Wisconsinan (MIS 3). Ice was able to extend into New York State blocking the Rome outlet to the Hudson Valley ponding deep proglacial lakes in the glacio-isostatically depressed Huron–Ontario–Erie basins recorded by thick glaciolacustrine sediments in paleovalleys. These were cannibalized by an expanding Late Wisconsinan ice sheet after ∼24 000 ybp recorded by extensive till sheets resting on a marked erosional unconformity, with drumlinized surfaces. Analysis and visualization of LiDAR data identifies discrete statistically validated flow sets of highly elongated streamlined bedforms (mega-scale glacial lineations (MSGLs)). These provide key evidence of a major reorganization of the ice sheet margin during deglaciation into lobate paleo ice streams shortly after 17 400 ybp. MSGLs are cut across earlier LGM drumlinized tills creating widespread "palimpsest" surfaces. At least two principal phases of fast ice flow can be identified, marked by large fluxes of sediment and the rapid building of large gravel and sand-dominated moraine complexes within interlobate depocentres, the largest glacial landforms in southern Ontario. Analysis of LiDAR data further reveals the common presence of DeGeer moraines where ice margins retreated in water, and iceberg scours. Future work using LiDAR mapping has the objective of fully documenting the number, extent, and timing of ice streams to enhance glaciological modelling when the ice sheet rapidly lost mass. [ABSTRACT FROM AUTHOR]

Geological survey and geochronological analyses were conducted in the Campo Imperatore plain to understand its Quaternary morpho-sedimentary and tectonic evolution. In the Late Pliocene-Early Pleistocene, low relief energy and steady and warm climatic conditions promoted a long phase of areal peneplanation, resulting in the formation of gently sloping landscape. With further regional uplift and changes in frequency/amplitude of the glacial-interglacial cycles (Early-Middle Pleistocene transition) and after establishment of the expansion-contraction cycles of the Apennine glaciers (Middle Pleistocene), the morpho-sedimentary processes become highly dynamic. In Middle Pleistocene, more than 100 meters of breccias deposited all along the slopes of the Gran Sasso range, followed by higher frequency processes of sedimentation, erosion and pedogenesis of Middle-Late Pleistocene to Holocene fluvio-glacial deposits. These have been progressively offset by synthetic and antithetic normal faults belonging to the Gran Sasso fault system, a 40-km-long seismogenic structure which released in the past earthquakes of Mw~7.

Geological survey and geochronological analyses were conducted in the Campo Imperatore plain to understand its Quaternary morpho-sedimentary and tectonic evolution. In the Late Pliocene-Early Pleistocene, low relief energy and steady and warm climatic conditions promoted a long phase of areal peneplanation, resulting in the formation of gently sloping landscape. With further regional uplift and changes in frequency/amplitude of the glacial-interglacial cycles (Early-Middle Pleistocene transition) and after establishment of the expansion-contraction cycles of the Apennine glaciers (Middle Pleistocene), the morpho-sedimentary processes become highly dynamic. In Middle Pleistocene, more than 100 meters of breccias deposited all along the slopes of the Gran Sasso range, followed by higher frequency processes of sedimentation, erosion and pedogenesis of Middle-Late Pleistocene to Holocene fluvio-glacial deposits. These have been progressively offset by synthetic and antithetic normal faults belonging to the Gran Sasso fault system, a 40-km-long seismogenic structure which released in the past earthquakes of Mw~7. [ABSTRACT FROM AUTHOR]

The geological map sheet Møn covers the island of Møn, the smaller adjacent islands Langø, Lindholm and Nyord as well as adjacent parts of Sjælland and Lolland. It comprises the geodetic map sheets 1511 I and 1511 II and areas on bordering sheets. Møn is surrounded by the Baltic Sea with the bay of Hjelm Bugt to the south, the straits of Grønsund and Ulvsund to the west, and the bays of Stege Bugt and Fakse Bugt to the north.Møn is divided into three glaciomorphological areas, namely a high, hilly landscape of Høje Møn to the east, a hummocky to parallel ridge landscape to the west and areas of marine deposits around Nyord and Ulvshale. The composite ridge landscape of Høje Møn constitutes a glaciotectonic complex comprising four individual glaciodynamic sequences, with the hill Aborrebjerg as the highest point (143 m a.s.l.). The parallel ridge hills consist of thrust-fault-displaced chalk sheets with superimposed glacial deposits. The thrust sheets are up to 80 m thick, of which 60 m constitute Maastrichtian chalk. The vertical displacement of the thrust sheets is about 150 m measured from the primary, undeformed pre-Quaternary surface located 25–30 m below sea level. The pre-Quaternary surface consists of chalk of Late Maastrichtian age, which forms a carbonate platform in the subsurface of Møn about 27 m below sea level. Chalk displaced by glacial tectonics is not restricted to Høje Møn but also appears in smaller thrust sheets and rafts in the small-ridged landscape around Stege Nor. In the chalk sheets along Møns Klint, most of the Late Maastrichtian succession is exposed. Cliff sections with chalk are also exposed at Hvideklint along the south coast of the island. However, here the glaciotectonic shear deformation has commonly altered the lithology into a chalk glacitectonite.The oldest Quaternary units deposited on the pre-Quaternary unconformity are Saalian till as well as sand and clay from the Eemian Interglacial. These units are overlain by Early Weichselian sand. The next Quaternary succession, the Ristinge Klint Till Formation, was deposited during the Ristinge ice advance in the early Middle Weichselian about 55 000–50 000 years ago. Then followed the Kraneled Formation (new formation) consisting of fluvial and lacustrine deposits. The following Klintholm Till Formation (adjusted formation) was deposited during the Klintholm ice advance 35 000–32 000 years ago. The Klintholm Till Formation is overlain by a more than 10 m thick unit of greyish glaciolacustrine clay with dropstones. Glaciofluvial sand with thin-layered intercalations of laminated mud and diamictites of the Kobbelgård Formation (new formation) are related to this unit and interpreted as deposited in a huge, partly ice dammed lake covering a large part of the present Baltic Sea and the southern part of Kattegat 32 000 to 28 000 years ago. The Kobbelgård Formation is overlain by sand and gravel of the Stubberup Have Formation (new formation) and tills of the Mid Danish Till Formation deposited by the NE Ice Advance from central Sweden about 23 000–20 000 years ago.Relatively shortly after the NE ice had melted away, the Young Baltic Ice advanced from the eastern part of the Baltic area. North-directed compressive deformation during this advance created the glaciotectonic complex of Møns Klint including the new unit Møns Klint Glaciodynamic Sequence. In the southern part of the complex, a steeply inclined imbricated fan was formed; towards the foreland to the north, the thrust faults became gently dipping and the tip-zone of thrusting is located under the landslides at Liselund. The composite ridges form a characteristic hilly landscape with elongate crests trending E–W.The curved coastline along Hjelm Bugt was formed by a glacial lobe, north of which a push moraine was built up. A number of spillways striking radially northward from the lobe were formed by meltwater discharged from its glacier ports, including the Borre, Maglemose and Røddinge depressions. Deposition of sand and gravel of the Ny Borre Formation (new formation) took place at this time. During the advance of the Young Baltic Ice over southern Denmark to the Eastern Jutland stationary line, a relatively thin lodgement till of the Lolland Till Formation was deposited, which is rich in chalk due to its truncation of the upthrusted chalk sheets.Towards the end of the Weichselian glaciation c. 17 000 years ago, the Young Baltic Ice melted back, leaving a residual ice cap in Skåne from where a recessive ice advance towards south-west reached Møns Klint, resulting in superimposed glaciotectonic deformation. During the Late Weichselian, freshwater lakes in the Hjelm, Tøvelde and Høje Møn areas were filled by clay and gyttja, with deposition that continued into the Holocene.During the Holocene, the former spillways were turned into fjords during the Atlantic transgression. Marine deposits mirroring the Littorina Sea are thus found in Maglemose and Borre Sømose. After the Atlantic transgression had established a sea level more or less corresponding to that of today, accretion of marine forelands and formation of a spit system started. In particular, this is the case for the areas of Ulvshale and Nyord. At the same time, vegetation migrated out into the numerous fjords, and peat began to accumulate. The last phase of sedimentation is confined to the formation of beach ridges in the coastal areas, typically covered by aeolian dunes, as can be seen on the coast at Klintholm Havn and Råbylille as well as along the north-eastern coast of Ulvshale.

The region at the foot of the Ajodhya hills in the Purulia district of West Bengal is considered to be one of the richest places in eastern India where evidence of microlithic cultures has been found. Some of the oldest dated microlithic sites in India are located in this part of Bengal. The present study presents the results of a recent archaeological survey of a 46 square kilometre area in the northwestern part of the Ajodhya foothills of Purulia, adjacent to the towns of Begunkodor and Jhalida. Three new microlithic sites were discovered during this exploration and are reported here along with the Quaternary stratigraphic contexts. In addition, preliminary observations of the microlithic artefacts recovered from these three new sites are discussed. The results of this study suggest that these newly discovered microlithic sites may provide new opportunities for more intensive studies in this region in the future. [ABSTRACT FROM AUTHOR]

The first Lower Palaeolithic (Acheulean) sites ever excavated in India are located in the Burhabalang river valley of the Mayurbahnj district of Orissa. It reveals that the Mayurbhanj Acheulean site complex has been under the scanner of prehistoric archaeologists for a long period. However, it is unfortunate to say that, despite being studied for nearly one century by several scholars, the implementiferous beds of the Burhabalang River valley have not been studied in detail till now. The present article brings forward an attempt to fathom the nature and the mode of origin of the Acheulean artifact-bearing beds of the Burhabalang river valley near Baripada town of Orissa. In this study approach of geo-archaeology is adopted to study and compare physical features like various geomorphological and lithological attributes of several Acheulean sites of this region. Besides, an attempt is made to understand the nature of occurrence of Acheulean artifact bearing-beds of this region and the mode of origin of these implementiferous beds too. Results of this study reveal that probably Acheulean artifacts bearing ferricrete horizons of the Burhabalang river valley were deposited some time during the middle Pleistocene, under the influence of a much more humid monsoonal climate. Perhaps prehistoric humans with Acheulean artifacts roamed in the river valleys of this region when deposition of ferruginous sedimentation or ferricrete was taking place. During the later time under the influence of a much drier climate ferruginous duricrust developed at the top of ferricrete sediments and Acheulean artifacts are now found deposited in the hard duricrust horizon. [ABSTRACT FROM AUTHOR]

The geological analysis of artesian borehole material from Sombor, Subotica, and Zrenjanin, was in the first campaign of detailed stratigraphic studies of Vojvodina in 1892-1895. The results of Quaternary stratigraphy from Zrenjanin were published by HalaVaTS more than a decade later (1914). The significance of the Zrenjanin, Sombor, and Subotica artesian well profiles for more than a century is considered the representative local profiles for the Quaternary stratigraphy of Vojvodina recognized by Serbian (Yugoslavian) and Hungarian geologists. Significant changes were after the taxonomical revision of molluscan material and its stratigraphic context, which was done through the excellent work of Krolopp in the 1970-ies. Unfortunately, the mentioned changes were not applied in the studies during the geological surveying of former Yugoslavia. The developments in Quaternary geology, changes in the Quaternary chronostratigraphic scale, and the results shown by this paper enable the lower Pleistocene fluvial deposits to be defined as the Pleistocene Corbicula beds, the Viviparus boeckhi Horizon. The lower Pleistocene at Zrenjanin was documented from 234.54 to 58.36 m depth. The interval between 234.54 and 208.50 m comprises the Upper Paludina – Viviparus vucotinovici zone, while the Viviparus boeckhi Horizons were identified between 135.18 m and 58.36 m. The interval between 58.36 m and 37.75 m is defined as Pleistocene (lower- and Middle Pleistocene) based on sedimentological and the molluscan record. The interval from 37.75 m to 21.67 m depth was identified as Middle Pleistocene, according to its lithology and the paleontological material. The fluvial sediments’ 21.69 m and 7.31 m depths cannot be determined according to the faunistic data; we can only consider them as Pleistocene age. The Holocene sediment and soil horizons ascend to a 2.90 m depth.

Det geologiske kortblad Møn omfatter Møn med de tilgrænsende øer Langø, Lindholm og Nyord samt mindre dele af Sjælland og Falster. Kortet består af dele af de topografiske kortblade 1511 I og 1512 II samt 1511 IV med randområder af tilgrænsende kortblade mod vest og nord.Møn opdeles i tre geomorfologiske områder: det stærkt kuperede Høje Møn mod øst, det småbakkede landskab omkring Stege Nor mod vest, og det flade marine forland omkring Nyord og Ulfshale. Høje Møn opbygges af opskudte skiver af skrivekridt og kvartære aflejringer, som det ses i Møns Klint. Skiverne er op til 80 m tykke, hvoraf skrivekridtet udgør ca. 50 m. Under hele Møn består prækvartæroverfladen af Maastrichtien skrivekridt i en dybde omkring kote –25 til –40 m. Mindre skiver af glacialtektonisk forstyrret skrivekridt optræder også omkring Stege Nor og langs sydkysten af det vestlige Møn ved Hvideklint.De ældste kvartære aflejringer er moræneler fra Saale-istiden og sand og ler fra Eem-mellemistiden. Derefter følger fluviale aflejringer og nedskylslag fra Tidlig Weichsel. Disse lag efterfølges af moræneler fra Ristinge Klint Till Formationen med over- og underliggende smeltevandsaflejringer fra Mellem Weichsel dannet under Ristinge Isfremstødet for ca. 55 000–50 000 år siden. Den næste enhed er Kraneled Formationen (ny formation), som efterfølges af moræneler tilhørende Klintholm Till Formationen (justeret formation) fra Klintholm Isfremstødet for 35 000–32 000 år siden. Formationen overlejres af mere end 10 m tykke enheder af gråt til olivengråt issøler med dropsten, smeltevandssand og lamineret fint sand samt diamikte aflejringer i Kobbelgård Formationen (ny formation). Denne formation blev aflejret i en issø, som dækkede store dele af Østersøen i en mildningsperiode for 32 000– 28 000 år siden. Denne enhed overlejres af eller er øverst sammenflettet med sand og grus tilhørende Stubberup Have Formationen (ny formation). Moræneler tilhørende den Midtdanske Till Formation blev aflejret under NØ-Isfremstødet for 23 000–20 000 år siden. Efter at NØ-Isen var smeltet tilbage fra østersøområdet, rykkede den Ungbaltiske Is frem fra den østlige del af Østersøen, hvorunder bl.a. Møns Klint og Hvideklint blev deformeret. En tilhørende strukturel enhed, Møns Klint Glacialdynamiske Kompleks, er defineret med fire sekvenser. Hele Hjelm Bugt dannede en glacial lobe, og nord herfor dannedes et randmorænestrøg. Radialt ud fra loben dannede smeltevandet store afløbskanaler fra gletsjerporte i den Ungbaltiske Is. Aflejring af sand og grus tilhørende Ny Borre Formationen (ny formation) skete i dette tidsrum. Under det Ungbaltiske Isfremstød blev Lolland Till Formationen aflejret som et relativt tyndt lag af moræneler.Ved slutningen af Weichsel-istiden for ca. 17 000 år siden smeltede den Ungbaltiske Is tilbage. Et residualt isdække i området nordøst for Møn sendte et genfremstød til det østlige Møn, som medførte en reorientering af skrivekridtskiverne i Møns Klint. I Sen Weichsel (17 000–11 700 år før nu) fandtes søbassiner på det sydlige Møn ved Hjelm og Tøvelde samt på Høje Møn, hvor en række ferskvandslag blev dannet, og aflejringen fortsatte et stykke ind i Holocæn.I Holocæn blev de tidligere afløbskanaler transgrederet under den atlantiske havstigning, hvorved fjorde skar sig ind fra nord og nordvest til midt på Møn. Herefter begyndte udbygningen af marine forlande, især mod nord i området Ulvshale og Nyord. De tidligere fjorde voksede til med planter, som omdannedes til tørveaflejringer. Den sidste sedimentationsfase skete langs kysterne, hvor strandvolde blev akkumuleret, og kystklitter af flyvesand blev dannet.

Beach nourishment is a popular engineering-with-nature (EWN) strategy used globally for shoreline stabilization and coastal storm damage reduction. Large-scale projects require dredging from offshore sand borrow sources. However, suitable sands for nourishment are not ubiquitous offshore, especially in sediment-starved southern NC. In 2015, >300 nautical miles (555 km) of sub-bottom, sidescan, bathymetry and 38 cores/grabs were collected in data gaps offshore southern NC and interpreted for geologic horizons and potential nourishment-compatible sand thickness. In addition, hundreds of paleochannels were mapped and evaluated for fill patterns and resource potential. Various forms of hardbottom were delineated, sometimes in close proximity to sand resources. Results show high spatial variability in the distribution of beach-compatible sands across the southern NC shelf, where only a thin sand veneer is observed in many locations, although some regions contained continuous deposits exceeding 3 m. The thickest shoal deposits (>5 m) were observed offshore New Hanover County Region. Underlying strata and bathymetry appear to affect channel shape and distribution. Channels with acoustically transparent fill may be suitable as nourishment sources, yet many channels show complex and variable fill suggestive of tidal and estuarine environments. Seafloor reconnaissance data are valuable in preventing multi-use conflicts on the shelf as shelf areas are increasingly being explored for other functions (e.g, wind farms, oil/gas, fish habitat). These findings provide a useful starting point for coastal managers seeking sufficient offshore sediment resources for nourishment in response to future storm events and sea-level rise. [ABSTRACT FROM AUTHOR]

Loess-paleosol sequences are the most intensively studied terrestrial archives used for the reconstruction of Late Pleistocene environmental and climatic changes in the Azov Sea region, southwest Russia. Here we present a refined chronostratigraphy and a multiproxy record of Late Pleistocene environmental dynamics of the most complete and representative loess–paleosol sequences (Beglitsa and Chumbur-Kosa sections) from the Azov Sea region. We propose a new chronostratigraphy following the Chinese and Danubean loess stratigraphic models that refines the subdivision of the Last Interglacial paleosol (S1) complex in two Azov Sea sites, resolve the uncertainty of the stratigraphic position of the weakly developed paleosol (L1SSm) in Beglitsa section, and allow for direct correlation of the Azov Sea sections with those in the Danube Basin and the Chinese Loess Plateau. More importantly, it may serve as a basis for better constraining local and regional chronostratigraphic correlations, and facilitate the interpretation of climatic connections and possible forcing mechanisms responsible for the climatic trends in the region. In addition, a general succession of environmental dynamics is reconstructed from these two vital sections, which is broadly consistent with other loess records in the Dnieper Lowland and Lower Danube Basin, demonstrating similar climatic trends at Glacial–Interglacial time scales. Furthermore, our results have important implications for the chronostratigraphic representativeness of Beglitsa as a key regional loess section and for the reconstruction of the temporal and spatial evolution of Late Pleistocene climate in the Azov Sea region.

Coastal systems have changed considerably in response to Quaternary glacial–interglacial variability. Here, we offer the first detailed assessment of geomorphic features and late Quaternary sedimentation dynamics in the Lošinj Channel in the Adriatic Sea. The present study attempts to resolve the complex evolution of the environments by applying high-resolution seismic records that build upon sediment core data. Within this coastal karst basin, a significant amount of sediment accumulated during the Quaternary. Notably, the existence of several prominent erosional and depositional environments was revealed. We distinguished recurrent episodes of fluvio-lacustrine and marine sedimentation that probably occurred since Marine Isotope Stage (MIS) 6. The preserved record consists of erosional features and subparallel and oblique reflectors attributed to glacial periods (Seismic Units SU-II, SU-IV, and SU-V). Interglacial units are acoustically semitransparent and generally reflection-free (Seismic Units SU-I and SU-III). The mutual influence of sea level and climate change, sill depth, and karst hydrology enabled environmental changes in the Lošinj Channel. The area proves to be important for Quaternary studies because it contains a long sediment succession spanning at least the middle and late Pleistocene and Holocene. Our study has implications for the assessment of the long-term palaeoenvironmental evolution of similar coastal settings and reconstruction of the regional palaeogeography which is in turn crucial for understanding prehistoric human occupation and/or dispersal. This is one of the few well-preserved records in the Adriatic Sea that provides insight into submerged landscapes and sea levels since the penultimate glacial. • The distinct Quaternary high-resolution seismic record in the eastern Adriatic. • A unique succession of submerged environments - both terrestrial and marine. • First record of paleoenvironmental variability since MIS 6 in the eastern Adriatic. • A model location for paleoenvironmental reconstructions in a Dalmatian-type coast. [ABSTRACT FROM AUTHOR]

Two succeeding phases in the evolution of Lipari island have been identified and are discussed in the present paper. At first, eight orders of marine terraces were recognized on the ground of geomorphological, sedimentological and paleontological evidences. The U234/U238 datings of the fossil shells recovered from terraces Ill and V have allowed to set the age of these ancient shorelines. These datings implemented with those from the literature, make the basis for the construction of an uplift/sinking diagram. From this latter it stems that a sinking has occurred approximately during the Eutyrrhenian. The subsequent rise took place at a rate of 0.73-0.33 cm/year,

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Global glaciations have varied in size and magnitude since the Early–Middle Pleistocene transition (~773 ka), despite the apparent regular and high-amplitude 100 ka pacing of glacial–interglacial cycles recorded in marine isotope records. The evidence on land indicates that patterns of glaciation varied dramatically between different glacial–interglacial cycles. For example, Marine Isotope Stages (MIS) 8, 10, and 14 are all noticeably absent from many terrestrial glacial records in North America and Europe. However, globally, the patterns are more complicated, with major glaciations recorded in MIS 8 in Asia and in parts of the Southern Hemisphere, such as Patagonia, for example. This spatial variability in glaciation between glacial–interglacial cycles is likely to be driven by ice volume changes in the West Antarctic Ice Sheet and associated interhemispheric connections through ocean–atmosphere circulatory changes. The weak global glacial imprint in some glacial–interglacial cycles is related to the pattern of global ice buildup. This is caused by feedback mechanisms within glacial systems themselves that partly result from long-term orbital changes driven by eccentricity. [ABSTRACT FROM AUTHOR]

The sedimentary succession exposed in the Gorzów Wielkopolski area includes Eemian Interglacial (MIS 5e) or Early Weichselian (MIS 5d–e) deposits. The sedimentary sequence has been the object of intense interdisciplinary study, which has resulted in the identification of at least two palaeolake horizons. Both yielded fossil remains of large mammals, alongside pollen and plant macrofossils. All these proxies have been used to reconstruct the environmental conditions prevailing at the time of deposition, as well as to define the geological context and the biochronological position of the fauna. Optically stimulated luminescence dating of the glaciofluvial layers of the GS3 succession to 123.6 ± 10.1 (below the lower palaeolake) and 72.0 ± 5.2 ka (above the upper palaeolake) indicate that the site formed during the Middle–Late Pleistocene (MIS 6 – MIS 5). Radiocarbon‐dating of the lacustrine organic matter revealed a tight cluster of Middle Pleniglacial Period (MIS 3) ages in the range of ~41–32 ka cal bp (Hengelo – Denekamp Interstadials). Holocene organic layers have also been found, with 14C ages within a range of 4330–4280 cal bp (Neolithic). Pollen and plant macrofossil records, together with sedimentological and geochemical data, confirm the dating to the Eemian Interglacial. [ABSTRACT FROM AUTHOR]

High‐resolution seismic and bathymetric data offshore southeast Ireland and LIDaR data in County Waterford are presented that partially overlap previous studies. The observed Quaternary stratigraphic succession offshore southeast Ireland (between Dungarvan and Kilmore Quay) records a sequence of depositional and erosional events that supports regional glacial models derived from nearby coastal sediment stratigraphies and landforms. A regionally widespread, acoustically massive facies interpreted as the 'Irish Sea Till' infills an uneven, channelized bedrock surface overlying irregular mounds and deposits in bedrock lows that are probably earlier Pleistocene diamicts. The till is truncated and overlain by a thin, stratified facies, suggesting the development of a regional palaeolake following ice recession of the Irish Sea Ice Stream. A north–south oriented seabed ridge to the north is interpreted as an esker, representing southward flowing subglacial drainage associated with a restricted ice sheet advance of the Irish Ice Sheet onto the Celtic Sea shelf. Onshore topographic data reveal streamlined bedforms that corroborate a southerly advance of ice onto the shelf across County Waterford. The combined evidence supports previous palaeoglaciological models. Significantly, for the first time, this study defines a southern limit for a Late Midlandian Irish Ice Sheet advance onto the Celtic Sea shelf. © 2020 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This quantitative reanalysis reviews the high-fidelity record of ice-sheet dynamics and ensuing sediment supply to the greater Lake Melville region of Labrador, Canada. The environment is strategically located close to a major ice divide of the Quebec-Labrador Dome (QLD) of the Laurentide Ice Sheet. More than 5000 km of acoustic records are examined along with multibeam bathymetric data acquired over the last 2 decades. Findings reveal a thin (1125 m), low-angle (0.15°–0.21°) ice stream once emanated from the eastern sector of the QLD, which likely over-deepened Cartwright Saddle, a major trough on the Labrador Shelf. Modeled-ice velocities during glaciation are 2500 ± m/yr, allowing the ice sheet to discharge 10,000± icebergs each year into the North Atlantic. The ice stream's flux may have caused a drawdown of the QLD, shifting the ice divide into Lake Melville's drainage basin. After deglaciation began ∼10.4 kyr BP, the ice stream had thinned to ∼820 ± 20 m, reducing ice stream ice velocities to ∼820 ± 50 m/yr. Vertical ablation of the ice sheet proceeded at rates of ∼0.17 m/yr and ice-marginal retreat was on the order of 140 ± m/yr (190 ± m/yr if stillstand pauses are excluded), which resulted in complete deglaciation of the 250 km-long basin in approximately 2500 years. The ice stream delivered, on average, 50 Mt/yr of deglacial sediment between 9 and 8 kyr BP; sediment loads associated with the six largest submarine moraines range 44–64 Mt/yr, delivered by a freshwater discharge 5-fold larger than for modern conditions. With 94 Gt of subglacial and deglacial sediment deposited in Lake Melville, the regional deglacial sediment yield is 300 t/km2/yr, perhaps ∼430 t/m2/yr if terrestrial deglacial deposits are included. Our findings confirm the existence of a Lake Melville ice stream during the Last glacial episode and highlight future research opportunities for empirical and modeling studies directed towards an understanding of ice-sheet dynamics. • A converging, thin, low-angle ice stream emanated from the eastern sector of the QLD, with flow through Lake Melville. • The ice stream velocity averaged ∼2500 m/yr and discharged ∼10,000 large icebergs each year to the North Atlantic. • The Laurentide Ice Sheet slowed to between 220 m/yr to 820 m/yr, during the 2500-yr period of deglaciation (7.9–10.4 kyr BP). • Subglacial discharge supplied ∼500% more freshwater than for modern conditions and carried a deglacial sediment load of 50 Mt/yr. • The Lake Melville Ice Stream is associated with a sediment yield of between 300 and 430 t/km2/yr. [ABSTRACT FROM AUTHOR]

Prepoštská jaskyňa Cave (Bojnice I) near Prievidza is an archaeological site with confirmed Neanderthal settlements. The discovered fossil material, including also osteological remains of avifauna, comes from trenches II and III excavated by Juraj Bárta in 1965–1967. The evaluated fossil and subfossil bird remains from the Last Glacial Period to Holocene demonstrated a presence of 37 species from 11 orders. The studied material was divided into four assemblages, from which the most important is the northern Lagopus-assemblage typical for cold climatic conditions of the Last Glacial. Identified bird assemblages helped to reconstruct palaeoenvironmental and climatic conditions at the site and in its vicinity. The osteological material was also taphonomically evaluated indicating activity of various taphonomic agents. [ABSTRACT FROM AUTHOR]

Studies in paleomagnetism, structural geology, and paleontology (mammals, mollusks, palynology) in the coastal sections of the Taman Peninsula north-western part (2017–18) resulted in definition of three sedimentary sequences. The sandy and clayey lower sequence (I) formed at 2.1–1.7 Ma. It contains a normally magnetised zone within deposits of reversed polarity correlated to the Olduvai Subchron and the Matuyama Chron. The middle sequence (II) is composed of the basal pebbles overlain by sands. The reversely magnetised deposits hosting the Sinyaya Balka site, the type locality of the Tamanian faunal complex, is correlated to the basal bed of the middle sequence II. The overlying sands are normally magnetised (Jaramillo Subchron) in the lower part and show reverse polarity (late Matuyama Chron) in the upper part. The sequence II is dated in the range of 1.3–0.78 Ma. The silty upper sequence (III) represents Middle-Late Pleistocene. The dissimilar displacement degree of the sequences reflect developmental stages of the Quaternary deformation. The sequence I is characterised by dip angles up to 70° is fragmented by faults into blocks. The sequence II filled the relief of the eroded surface of the sequence Member I and also displaced by faults. The faulting separated the bone-bearing body of the Taman faunal complex as a rock land-slide. The attitude of the member III outline an anticline with a gentle south-western and a steeper north-eastern limbs eroded by land-slides and marine abrasion. During its entire life the anticline was affected by mud volcanism. The anticline continues its development at the present stage. [ABSTRACT FROM AUTHOR]

We present a geomorphological, stratigraphical and geochronological study reconstructing a suite of paleo-surfaces in a 200 km-long coastal sector of the central Tyrrhenian Sea between Argentario and Circeo promontories. Identification of the near-shore deposits associated with these paleo-surfaces allow us to define corresponding marine terraces and paleo sea-levels. 40Ar/39Ar and ESR/U-Th geochronologic constraints on key deposits provide correlation with the terraces previously recognized in the coast of central Latium, refining their correlation with the Marine Isotopic Stages. Results of this study enable us to: Propose a re-assessment of the ages for the sea-level markers of MIS 5.5, 5.3, 5.1 in the central Tyrrhenian Sea; Suggest that a continuous tectonic uplift with an average rate of 0.224 mm/yr affects the Latium coast since 200 ka; Provide new evidence for a MIS 5.5 paleo-sea level marker occurring at ~35 m a.s.l. on the coastal sector extending from Montalto di Castro to Latina, while it possibly drops down and connects to a paleo sea-level ranging 10 - 5 m between Monte Circeo and Gaeta, previously attributed to this interglacial; Discussing possible evidence of similar elevation of the sea level during MIS 5.5, 5.3 and 5.1 interglacials in the Tyrrhenian Sea; Compare this datum with those from the western Pacific and several coral reefs, where the differences with respect to tectonically stable regions were attributed either to tectonics or to the Glacial Isostatic Adjustment, showing that the presented record of sea-level markers may have a strong impact on modeling the post-glacial effects in the Mediterranean Sea and on the paleoclimatic and paleoceanographic studies in this region. [ABSTRACT FROM AUTHOR]

The dynamics of the British-Irish Ice Sheet (BIIS) during the Last Glacial were conditioned by marine-based ice streams, the largest of which by far was the Irish Sea Ice Stream (ISIS) which drained southwest across the Celtic shelf. The maximum extent and timing of the ISIS have been constrained by onshore evidence from the UK and Ireland, and by glacigenic sediments encountered in a small suite of vibrocores from the UK-Irish continental shelf, from which a single radiocarbon date is available. These data have long supported ice advance to at least the mid-shelf, while recent results suggest the ISIS may have extended 150 km farther seaward to the shelf edge. The glacigenic sequences have not been placed within a secure seismic-stratigraphic context and the relationship between glaciation and the linear sediment megaridges observed on the outer shelf of the Celtic Sea has remained uncertain. Here we report results of sedimentological, geochemical, geochronological and micropalaeontological analyses combined with a seismic-stratigraphic investigation of the glacigenic sequences of the Celtic Sea with the aims of establishing maximum extent, depositional context, timing and retreat chronology of ISIS. Eight lithofacies packages are identified, six of which correlate with seismic facies. Lithofacies LF1 and LF2 correlate to a seafloor seismic facies (SF1) that we interpret to record the postglacial and Holocene transgressive flooding of the shelf. Lithofacies LF10 (till), LF3, LF4 and LF8 (glacimarine) correlate to different seismic facies that we interpret to be of glacigenic origin based on sedimentological, geotechnical and micropalaeontological evidence, and their distribution, supported by geochemical evidence from lithofacies LF8 and LF10 indicate extension of ISIS as far as the Celtic Sea shelf break. New radiocarbon ages on calcareous micro- and macrofauna constrain this advance to be between 24 and 27 cal ka BP, consistent with pre-existing geochronological constraints. Glacimarine lithofacies LF8 is in places glacitectonically contorted and deformed, indicating ice readvance, but the nature and timing of this readvance is unclear. Retreat out of the Celtic Sea was initially rapid and may have been triggered by high relative sea-levels driven by significant glacio-isostatic depression, consistent with greater ice loads over Britain and Ireland than previously considered. • The Irish Sea Ice Stream extended as far as the continental shelf break between 27 and 24 ka during Marine Isotope Stage 2. • Initial retreat may have been conditioned by high relative sea level as a function of glacio-isostatic depression. • The observation that the ISIS extended as far as the shelf break implies that this advance was transient and not steady state. • An Arctic benthic foraminiferal fauna characterises glacimarine muds deposited during this advance. • Retreat northwards out of the Celtic Sea was rapid. [ABSTRACT FROM AUTHOR]

Abstract Tectonic movements among the African, Arabian, Aegean, and Anatolian Plates have deformed the eastern Mediterranean Basin. Since the late Pliocene, these movements caused transtensional opening of the NE-trending Antakya Graben. Tectonic uplift coupled with Quaternary sealevel fluctuations has produced several stacked marine terraces along the Mediterranean coasts on the Antakya Graben. Here, molluscs from terrace deposits that sit on both Graben flanks at elevations between ~ 3 and ~ 175 m were dated using standard electron spin resonance (ESR) dating. For molluscs in situ in the terraces, the ESR ages ranged from ~ 8.3 to ~ 214 ka, but most of the dated terraces contained molluscs reworked from several earlier deposits due to later tectonic movements, sealevel fluctuations, and associated sedimentary processes. By dating in situ fossils, such as Lithophaga , within or just above the basal contacts for the marine terraces, uplift rates were calculated on both sides of the Antakya Graben. North of the Asi River, the regional uplift rate ranges from ~ 0.43 ± 0.11 mm/yr at Samandağ to as high as 2.08 ± 0.70 mm/yr at Mağaracık Dump. South of the Asi River, uplift rates range from 0.81 ± 0.14 mm/yr at the Cliffside terrace to 2.33 ± 0.60 mm/yr at Meydan Dump I. Rather than regional movements, however, local active normal or transtensional faults, such as the Gözene, Altın, and Sinanlı Faults mainly uplifted these deposits. Highlights • Molluscs from raised marine terraces with its deposits analyzed by electron spin resonance (ESR) method. • In this study, the MIS 5a/5e shoreline indicators were found at about 60 m and 100 m around of the Antakya Graben. • The high uplift rate along the eastern Mediterranean coast is tectonically emphasized as an active coast area in contrast to other Levant coasts. [ABSTRACT FROM AUTHOR]

Understanding the style and pattern of retreat of the offshore sectors of the last British-Irish Ice Sheet (BIIS) is critical to any attempt to reconstruct its history following the Last Glacial Maximum (LGM). This paper presents a new seismo-stratigraphic analysis of Quaternary deposits on the inner continental shelf offshore of southwestern Scotland. It correlates these data with new high resolution seafloor bathymetry and sediment cores to reconstruct the post-LGM retreat dynamics of the Hebrides Ice Stream, a major outlet of the last BIIS which drained across the continental shelf offshore of northwest Britain. Two primary glacigenic units (Units III and IV) are observed in seismic sequences from the region. Unit III partly corresponds to the previously defined Barra Formation, but is re-interpreted here as a time-transgressive subglacial to ice-proximal deposit. On the mid-shelf, this unit comprises grounding-zone wedges (GZWs). Within inshore waters and sea lochs Unit III can be found at or near seabed, where it is associated with retreat moraines, as well as with proglacial outwash sediments near the Kintyre coast (RSL ~10 m OD). The younger Unit IV (equivalent to the Jura Formation) represents ice-proximal to hemipelagic conditions. Bathymetric data imaged streamlined subglacial landforms recording ice sheet flow onto the inner shelf and a variety of transverse landforms collectively interpreted as moraines recording episodic retreat. These new data indicate that during the last deglaciation of the shelf offshore of southwestern Scotland the retreat dynamics of the Hebrides Ice Stream followed three main stages: i) tidewater margin retreat punctuated by stillstands on the inner shelf, ii) topography-controlled fjordic retreat, with evolution from a coherent ice-sheet to separate tidewater glaciers, and iii) stabilisation at the transition from a tidewater to land-based ice margin. [ABSTRACT FROM AUTHOR]

The Gulf of Guayaquil, Southern Ecuador, is the largest tidal system of the Pacific margin of South America. The incipient oceanic tide has a tidal range of over 1 m and is amplified on the continental shelf, which is widened in this area by the tectonic activity related to the northward escape of the North Andean Block. The head of this embayment connects to the Guayas River, roughly running along the dextral strike-slip fault bounding the North Andean Block. The Guayas River connects to the Gulf of Guayaquil through a tide-dominated delta, the supratidal part of which is composed of mangroves drained by a network of tidal channels. The river channels merge into the Jambelí Channel, a subtidal valley forming the main distributary channel of the delta. Very high resolution seismic profiles collected at the junction between the Jambelí Channel and the Gulf of Guayaquil show the architecture of several depositional sequences preserved in the first 0.1 s twt beneath the sea bed. These sequences mainly consist of a lowstand to transgressive systems tract comprised of fluvial to estuarine channels topped by a highstand systems tract of prodeltaic muds. The progradational muds volumetrically dominate the stratigraphic record and characterize the Guayas delta facies. By contrast, the near bed features close to the mouth of Jambelí Channel show the present dominance of tidal scour, forming hollows up to 50 m deeper than the surrounding area, reworking the underlying deposits and forming levees or, inside the subtidal valley, tidal ridges. The prodeltaic muds may reach and cover the tidal scour hollows during the late highstand only, in favor of a damping of tides due to the reduction of the tidal prism caused by the advance of the Guayas delta. The sequences preserved in the outer part of Jambelí Channel pinch out toward a hinge line located along the Puná - Santa Clara fault system. This fault system is responsible of the uplift and emergence of a topographic barrier at the entrance of the Jambelí Channel. As a result, the Estero Salado was progressively disconnected from the Gulf and the tidal flows were concentrated in the Jambelí Channel, bringing about tidal scour hollows. In the meantime, the tidal prism was maintained and subsidence took place in a sub-basin located landward of the uplifting barrier. This caused the Jambelí Channel to remain subtidal during most of the past sea-level highstands, in spite of the large amount of sediment supplied by the Guayas River. [ABSTRACT FROM AUTHOR]

The aminostratigraphy of up to 1000 m of glacial and interglacial sediments in the North Sea Basin (NSB) is compiled from multiple boreholes sites and dated using strontium isotope (Sr) analysis to provide a chronological framework extending throughout the Quaternary. The Quaternary aminostratigraphy within the NSB can be divided into five amino zones (AZ), AZ1 (youngest) to AZ5 based on alle/Ile ratios which are used to correlate depositional events recorded in sedimentary facies from multiple borehole sites. The new relative and absolute chronology also ties to seismostratigraphy and multi-generational tunnel valley fill. Early Pleistocene sediments produce AZ5 ratios with Sr ages around 1.4–1.5 Ma deposited in marine to glacimarine conditions. Sediments with AZ4 ratios are constrained by Sr ages and magnetic polarity to 1.3–0.9 Ma, spanning the eccentricity to axial tilt insolation periodicity change of the Mid Pleistocene Transition (MPT). Some coarse-grained sedimentary units with AZ4 ratios may be linked to ice proximal deposition during the MPT. Sediments with AZ3 ratios are poorly chronologically constrained to between 1.1 and 0.26 Ma. At least one episode of diminished coarse clasts and increased foraminiferal diversity during this Mid Pleistocene time suggests a progression from ice proximal to warmer, possibly interglacial conditions. Furthermore, the stratigraphically deepest generation of tunnel valleys cut strata with AZ3 ratios indicating subglacial conditions at least once during the Mid Pleistocene. Sediments with AZ2 ratios corresponding to MIS7-5 are tied to seismic units including a thick (up to 40 m) deformation till, suggesting glacial incursion into the NSB during MIS6 followed by tunnel valley cutting of the this till, thought to be an MIS6 event also. The geometry and cross-cutting complexities of such tunnel valleys precludes further correlation of this ice extent. The youngest aminostratigraphic zone, AZ1, is recognised in all boreholes and well constrained to MIS4-2 and the youngest set of tunnel valleys, attributed to a single or multiple glacial advances at this time. [ABSTRACT FROM AUTHOR]

The results of stratigraphy of the Sombor and Subotica boreholes were first results of geological examination of borehole material from Vojvodina published by Halaváts in 1895. These geological profiles, alongside the borehole profile in Zrenjanin, were recognized as “standard” profiles for Quaternary geology and stratigraphic correlation pertaining to Vojvodina. However, the results of taxonomical revisions for malacologic material, published in 1977 by Krolopp and which presented significant changes in stratigraphy, have not been implemented in the results of geological mapping/surveying. According to new advances and results regarding Quaternary stratigraphy, Lower Pleistocene sediments can be better defined using Pleistocene Corbicula beds, the Viviparus boeckhi Horizon and the results yielded by this paper. In the case of the Sombor borehole, the Lower Pleistocene was defined at a depth from 48.13 m to 149.5 m, according to its palaeonological record (molluscan assemblage). The Lower- and/or Middle Pleistocene were defined as the interval between a 35.45 m and 48.13 m depth, based on sedimentology (lignite) and malacology. The interval from 15.21 m to 35.45 m depth was identified as Pleistocene, based on superposition and palaeontological material. The yellow quartz sand horizon at 9.74 m–15.21 m remains undefined. The Holocene yellow silty-clay horizon, which ascends to a 9.74 m depth, was identified as Holocene, according to the palaeontological content of the same sediments found in the brickyard in the vicinity of Sombor. In the case of the Subotica borehole, the Lower Pleistocene – based on palaeontological records – was defined at a depth between 99.6 m and 124.5 m. The depth from 2.2 m to 99.6 m could not be exactly identified as Pleistocene, while Holocene quicksand ascended to a 2.2 m depth. [ABSTRACT FROM AUTHOR]

The Banc d'Arguin (BA - Mauritania) has the double originality of being a shallow water platform (SWP) located on the edge of a sandy desert. This arrangement is rare in the world: Shark Bay in Australia, the western edge of the Persian Gulf and the Namibian margin are the main examples. BA's detailed study both in the marine part of the platform and on the coastal plain has highlighted the peculiarities of the Late Holocene parasequence (LH). In the basin, it is made up of two units recognized in seismic reflection: U5 surmounted by U6 / U7 in lateral variation of facies. U7 also constitutes most of the coastal plain, the construction of which Dia (2013) described in 5 stages. On its arrival, the postglacial Nouakchottian sea invaded areas determined by the construction and progression of ergs during the glacial episode (Azefal to the north, Agneitir and Akchar to the south). Their orientation defined the axes of penetration of the sea in the inter-ergs (Ras el Mâ, sebkha Acheil). In addition, the estuaries of the paleo-wadis, functional during the wettest episodes, were occupied by the sea (Khatt des Ogols). The ingression thus exceeded 12 km in Ras el Mâ and 10 km in the sebkha Acheil. The subsequent development was characterized by the clogging of the bay heads. It mainly used wind sands pushed in the axis of thalwegs and inter-ergs. The stability of the sea level since its arrival at its current level limited accommodation. The accommodation / supply ratio of Cattaneo and Steel (2003) was well below 1. The LH parasequence is therefore generally thin but very extensive on the surface. It is made almost entirely of sandy deposits characteristic of the inter and supratidal coastal environments: beach ridges and sedimentary spits, coastal dunes, large sand-flats which evolved into sabkhas for the oldest, as progradation progressed. The occasional use of the high points of the shore by the Neolithic populations underlined the coastal morphology. The description of the arrangement of the sedimentary subunits formed during the five phases of the period shows that it was formed by progradation with little aggradation during a phase of normal high-level regression. The comparison of the conditions prevailing in the other SWPs identified in the world shows that it is not the transgressive or regressive tendency of the deposits which is their most striking character. The very different lithology of the deposits is more discriminating and underlines the role played by desert sand inputs in the expression or not of other modes of biogenic and/or chemical sediment production. In the case where there are significant wind and fluvial siliciclastic components (northwest coast of Namibia) or significant wind inputs (BA in Mauritania), the production of biogeochemical carbonate components is reduced (Namibia) or even prevented (Mauritania). On the contrary, when the detrital inputs from a nearby desert environment are low (Shark Bay in Western Australia) or inefficient to almost non-existent (west coast of the Persian Gulf), the biogeochemical processes involved in the development of carbonates become predominant and lead to the formation of carbonate platforms. This continuum of models offers the possibility of identifying the amplitude of the desert signature in the paleogeographic reconstructions of certain platforms. • The Arguin Bank (Mauritania), a shallow water platform influenced by a desert. • A detrital Late Holocene parasequence in both the Arguin basin and the coastal plain. • Three similar shallow water platform identified: Shark Bay, Persian Gulf, Namibia. • Massive detrital inputs counteract chemical and biological sedimentary processes. • From a detrital model to a biochemical one, a continuum of forms in the world. [ABSTRACT FROM AUTHOR]

We report a luminescence dating study at Jiufangtai Section in the Salawusu River Valley located in the southeastern margin of the Mu Us Desert, Inner Mongolia, China. The section consists of interbedding sandy deposits of aeolian and fluvio-lacustrine facies. As this is where the stratotype section for the Salawusu Stage of the Upper Pleistocene period in China's Quaternary stratigraphy was defined, the chronology of its sedimentary sequence is of paramount importance. In this study, we focus on the upper part of the section. Seven samples were dated with a range of protocols using quartz and potassium feldspars. The SAR equivalent dose of coarse-grained quartz ranges from 16 Gy to 67 Gy and those of pIR100IR225 for the feldspars of the same size are between 40 Gy and 125 Gy. The differences up to a factor of two in equivalent dose observed for the two mineral fractions cannot be reconciled by the dose rate effect. The youngest sample gives near zero OSL signal for quartz and an equivalent dose of less than 3 Gy for the feldspar fraction, pointing to an adequate bleaching condition for the recent sedimentary environment. However, there is a relatively large scatter in equivalent dose for all the coarse-grained quartz samples. This poses a major challenge in evaluating the equivalent doses for dating in terms of degree of zeroing at deposition, an aspect that is usually irrelevant in desert areas. As luminescence property may affect the interpretation of the dating results, a series of experiments are designed to examine the stability of luminescence signals and saturation dose. For such sedimentary sequences with highly dynamic shifts in facies as in the Salawusu River Valley, the geological processes involved in solar resetting may be complicated. We will discuss how a variety of factors can be considered when optimizing the protocols for accurate dating of the lacustrine-aeolian deposits. [ABSTRACT FROM AUTHOR]

Eastern Oregon contains the deepest gorge in North America, where the Snake River cuts vertically down 2300 m. This deep gorge is known as Hells Canyon. A landscape containing such a topographic feature is likely undergoing relatively recent deformation. Study of the Burnt River, a tributary to the Snake River at the upstream end of Hells Canyon, yields data on active river incision in eastern Oregon, indicating that Quaternary faults are a first order control on regional landscape development. Through 1:24,000-scale geologic mapping, a 500,000-year record of fluvial incision along the Burnt River was constructed and is chronologically anchored by optically stimulated luminescence dating and tephrochronology analyses. A conceptual model of fluvial terrace formation was developed using these ages and likely applies to other non-glaciated catchments in eastern Oregon. Mapped terraces, inferred to have formed during glacial-interglacial cycles, provide constraints on rates of incision of the Burnt River. Incision through these terraces indicates that the Burnt River is down-cutting at 0.15 to 0.57 m kyr − 1 . This incision appears to reflect a combination of local base-level adjustments tied to movement along the newly mapped Durkee fault and regional base-level control imposed by the downcutting of the Snake River. Deformation of terraces as young as 38.7 ± 5.1 ka indicates Quaternary activity along the Durkee fault, and when combined with topographic metrics (slope, relief, hypsometry, and stream-steepness), reveals a landscape in disequilibrium. Longer wavelength lithospheric dynamics (delamination and crustal foundering) that initiated in the Miocene may also be responsible for continued regional deformation of the Earth's surface. [ABSTRACT FROM AUTHOR]

The uplift of the coastal cordillera of central Ecuador is a likely consequence of the subduction of the Carnegie Ridge, a 400-km-long and 2-km-high topographic asperity. This study aims at analyzing the impact of the subduction of the Carnegie Ridge on the continental shelf sedimentation during the Quaternary. We interpret high-resolution (50–450 Hz frequency) multi-channel (72 channels) and single-channel (Sparker) seismic data, piston cores, sediment profiles (3.5 kHz), and high-resolution multibeam bathymetry acquired during the ATACAMES cruise with the RV L’Atalante in 2012. In the La Plata Island–Cabo San Lorenzo Peninsula region, the results show a full and detailed record of the last ten Quaternary sedimentary sequences deposited in intra-shelf basins, at and -just seaward of the shelf break. These 100-ka-scale sequences are tied to piston core data, to well-dated Quaternary onshore exposures and to a flight of coastal marine terraces on Cabo San Lorenzo Peninsula and La Plata Island. These sequences correlate with the global ice volume and deep marine temperature changes (d18O) for the last 0.7 Ma, which points to a strict climatic control on depositional sequence development and preservation. However, the subsidence of the continental shelf acoustic basement, estimated by the stepwise backstripping of the sedimentary record, exhibits a complex deformation pattern with uplifting and subsiding regions. Deep marine seismic data, currently under processing, show evidence for a subducted seamount beneath La Plata Island and GPS data indicate an important interplate coupling in the same area with the potential to generate a Mw 7–7.5 earthquake. The pattern of the continental shelf deformation is consistent with the shape of this seamount. We tested the hypothesis of a link between the margin deformation and the subduction of the seamount, by comparing a stepwise subduction of the seamount to the palinspastic restoration of the deformation of the continental shelf for the last 1 Ma. This comparison shows that the collision probably started c.500 ka ago, together with the syntectonic sedimentation, and drastically slowed down by c.50 ka, with the sealing of most of the deformation on the shelf. [ABSTRACT FROM AUTHOR]

The Aberdeen Lake region of central mainland Nunavut is a former core region of the Laurentide Ice Sheet that is characterized by streamlined glacial landforms classified into multiple crosscutting flow sets and near continuous till blanket. The presence of widespread till near the centre of the Keewatin Ice Dome raises questions about its origin. Detailed drillcore logging revealed a complex stratigraphy consisting of at least 6 till units, variably preserved across the study area. Till provenance analysis indicates deposition by near opposite-trending ice flow phases, interpreted as evidence of reconfiguration of the Keewatin Ice Divide. At the surface, large north–northwesterly aligned landforms are present across the study area. The till stratigraphy within these landforms indicates the same NNW ice flow phase is responsible for considerable till production. This ice flow phase is also correlated to a long regional dispersal train of erratics toward the Gulf of Boothia. The production of an extensive, thick (~ 12 m), till sheet during the NNW-trending ice flow phase occurred far from the ice margin at a time of extensive ice cover of mainland Nunavut, likely from an east–west oriented ice divide. A deglacial westerly trending ice flow phase formed small drumlins atop the larger NNW streamlined till ridges and deposited a surficial till unit that is too thin to mask the NNW flow set across the study area. It is proposed that the Boothia paleo-ice stream catchment area propagated deep into the Laurentide Ice Sheet and contributed to significant till production in this core region of the Keewatin Sector prior to the westerly ice flow shift. The apparent relationship between till thickness and the size of the associated or correlated drumlins, flow sets, and dispersal trains indicates complex erosion/deposition interplay is involved in the formation of streamlined subglacial landforms. [ABSTRACT FROM AUTHOR]

The North Westland deformation front runs offshore for 320 km between Cape Farewell and Hokitika at a distance of 3–30 km from the coast. From marine seismic reflection profiles integrated with published sediment core and coastal uplift data, we infer late Quaternary activity on six major reverse faults. The principal structures are the Cape Foulwind, Kahurangi and Kongahu faults and the newly named Farewell, Elizabeth and Razorback faults. They include Late Cretaceous and Paleogene rift faults that were reactivated as reverse faults during the late Cenozoic. Best estimates of late Quaternary (<120 ka) slip rates for different faults range from 0.05–0.75 mm a–1. Nine potential earthquake sources are identified, including four segments of the Cape Foulwind Fault. They are of length c. 20–120 km, are potentially capable of producing moderate- to large-magnitude earthquakes ofMw6.7–7.8 and represent a seismic risk to coastal communities. Best estimates of recurrence intervals for individual fault sources range from about 7600 years to 30,400 years, with large uncertainties in slip rates of up to –0.4, +1.0 mm a–1reflected by the wide range of recurrence intervals. [ABSTRACT FROM PUBLISHER]