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Abstract The mass extinction at the Cretaceous–Palaeogene boundary is widely attributed to sudden and severe climate changes forced by bolide impact and/or flood basalt volcanism. In terrestrial depositional settings, these changes may potentially be recorded by palaeosols. To test the ability of pedogenic features to record both long‐term climate and shorter‐term changes preceding and following the Cretaceous–Palaeogene extinction event, palaeosols in the Upper Cretaceous (Maastrichtian) Naashoibito Member of the Ojo Alamo Formation and the lower Palaeocene (Danian) Nacimiento Formation in the San Juan Basin of north‐western New Mexico, USA, were examined, including data from previous studies. The fine‐grained facies of the Naashoibito Member comprises grey to greenish‐grey and red‐banded mudstones displaying pedogenic features including colour mottling, root traces, cutans, ped fabrics, pedogenic slickensides and calcareous nodules. Aside from a high‐chroma horizon at the formation base, palaeosols in the lower Nacimiento Formation are broadly similar to those observed in the Naashoibito Member. Lateral and vertical variability of the pedogenic features between correlated sections suggest that soil hydrology varied spatially and temporally from very saturated to seasonally well‐drained, with temporal variations controlled by basin sedimentation rates. Abrupt and/or catastrophic climate events precisely at the Cretaceous–Palaeogene boundary are not recorded due to an unconformity at the top of the Naashoibito Member. However, the presence of kaolinite in the clay mineral assemblage of the Nacimiento Formation, particularly near the formation base, but not in the Naashoibito Member, indicates episodic warmth and short (104 years) intervals of more intense weathering conditions during the very early Danian as compared to the late Maastrichtian. Aside from short warm intervals, the overall palaeoclimate during deposition of both formations was warm and consistently subhumid to humid and seasonal, suggesting no substantial long‐term (105–106) climate change took place across the Cretaceous–Palaeogene boundary in the San Juan Basin.

Siliciclastic deposits and dolostones of the Å Ä·ervelis Formation in southwestern Latvia were studied in outcrops, polished slabs, thin sections, and by geochemical methods, including stable isotope analyses. Siliciclastic fluvial deposits alternate with soils and carbonates. As the soil processes became dominant, up to 6 m thick dolocretes formed, but they still preserve remnant sedimentary structures and textures. The strong role of soil processes is indicated by the presence of ooids and pisoids together with fine laminar layers, chert and phosphatic inclusions, rhizoids, and stable isotope values. Peculiar vertical clay-dolomite structures, up to 1.7 m long, are root structures or their combination with Vertisol-like soil development. The extensive development of soil processes and formation of the vertical structures was stimulated by seasonally wet monsoon climate. The scarcity of fossils in the studied deposits does not allow their age to be determined precisely, but probably the thick dolocrete unit in the upper part of the studied succession formed during the end-Devonian glaciation and the period of related sea regression.

The mass extinction at the Cretaceous–Palaeogene boundary is widely attributed to sudden and severe climate changes forced by bolide impact and/or flood basalt volcanism. In terrestrial depositional settings, these changes may potentially be recorded by palaeosols. To test the ability of pedogenic features to record both long‐term climate and shorter‐term changes preceding and following the Cretaceous–Palaeogene extinction event, palaeosols in the Upper Cretaceous (Maastrichtian) Naashoibito Member of the Ojo Alamo Formation and the lower Palaeocene (Danian) Nacimiento Formation in the San Juan Basin of north‐western New Mexico, USA, were examined, including data from previous studies. The fine‐grained facies of the Naashoibito Member comprises grey to greenish‐grey and red‐banded mudstones displaying pedogenic features including colour mottling, root traces, cutans, ped fabrics, pedogenic slickensides and calcareous nodules. Aside from a high‐chroma horizon at the formation base, palaeosols in the lower Nacimiento Formation are broadly similar to those observed in the Naashoibito Member. Lateral and vertical variability of the pedogenic features between correlated sections suggest that soil hydrology varied spatially and temporally from very saturated to seasonally well‐drained, with temporal variations controlled by basin sedimentation rates. Abrupt and/or catastrophic climate events precisely at the Cretaceous–Palaeogene boundary are not recorded due to an unconformity at the top of the Naashoibito Member. However, the presence of kaolinite in the clay mineral assemblage of the Nacimiento Formation, particularly near the formation base, but not in the Naashoibito Member, indicates episodic warmth and short (104 years) intervals of more intense weathering conditions during the very early Danian as compared to the late Maastrichtian. Aside from short warm intervals, the overall palaeoclimate during deposition of both formations was warm and consistently subhumid to humid and seasonal, suggesting no substantial long‐term (105–106) climate change took place across the Cretaceous–Palaeogene boundary in the San Juan Basin. [ABSTRACT FROM AUTHOR]

The c. 100 myr extensive fossil record of bee brood nests and cells (calichnia) in siliciclastic sedimentary deposits, or palaeosols, is virtually devoid of the presence of their producers. The absence of a more specific assignment to a producer of the different ichnogenera of the ichnofamily Celliformidae precludes their use in phylogenetic and palaeobiogeographic studies. Omission surfaces developed in incipient carbonate palaeosols during the late Holocene (middle Neoglacial), c. 2975 yr cal BP, on the southwest coast of mainland Portugal show insect calichnia in dense ichnofabrics dominated by shallow discrete cells (Palmiraichnus castellanosi) and cells at the terminus of vertical shafts. At Carreira Brava, one of the studied sites, bees ready to abandon their cells were found in an exceptional state of preservation inside the sealed brood chambers. The chambers also preserve the inner cell hydrophobic polymerized membrane and remains of the monospecific Brassicaceae‐type pollen provision. Although the cause of mass mortality remains a mystery, oxygen depletion due to sudden flooding of the nesting substrate and consequent or overnight temperature drop, just before emergence, are plausible causes. The anaerobic conditions and later rapid carbonate diagenetic lithification are the likely causes of the preservation of the bees and the inner cell organic membrane. The favourable climate conditions for the development of successive, dense ichnofabrics from an omission suite dominated by bee brood cells may be the result of slightly colder and higher‐precipitation winters during the Neoglacial interval. [ABSTRACT FROM AUTHOR]

Abstract The McMurray Formation in McMurray Depocentre, Canada, is typically subdivided into stratigraphic units based on regionally mappable marine mudstones, the bases of which define flooding surfaces (bottom to top: Lower McMurray, C2, C1, B2, B1, A2, A1 depositional unit). However, the McMurray Formation comprises a variety of palaeoenvironments, with the north‐eastern Firebag Tributary hosting significant delta‐plain deposits in the Lower McMurray and B1 depositional units. Facies analysis of 60 cores and 4763 wireline logs was used to resolve the palaeoshoreline trajectory and stratigraphic architecture in Firebag Tributary. Of 14 identified facies, three delta‐plain facies reveal: (1) eluviated palaeosols, interpreted as shrublands and woodlands formed during base‐level fall; (2) gleyed palaeosols, interpreted as tidal marshes; and (3) coals formed in coastal mires, the two latter facies are interpreted to accumulate during base‐level rise. Eluviated palaeosols occur below the Lower McMurray coal seam, implying valley incision and a maximum regressive surface. Gleyed palaeosols underlying the coal seam atop the B1 depositional unit do not record base‐level fall. Wetting‐upward coals overlying either palaeosol facies indicate base‐level rise (i.e. major flooding surface). B1 depositional unit coals and gleyed palaeosols are overlain by shallow‐marine facies or are eroded by wave ravinement during transgression. Consequently, the tops of coals or gleyed palaeosols correlate to the bases of regional marine mudstones elsewhere in McMurray Depocentre. Stratigraphic cross sections showcase palaeoshoreline regression and transgression. During the Lower McMurray and B1 depositional units, widespread coals and palaeosols indicate the palaeoshoreline resided near the western edge of Firebag Tributary. Regression during C2 through B2 depositional units and A2 and A1 depositional units resulted in palaeoshorelines near the Alberta–Saskatchewan border. To complement a previously dated Lower McMurray ash (121.39 ± 0.2 Ma), a new high‐confidence maximum depositional age from ash in the B1 coal seam (115.09 ± 0.16 Ma) allows an estimate to be made of depositional duration, indicating depositional units represent ca 0.16 Myr.

Buried profiles on Precambrian granites of Dharwar Craton have been explored to understand role of endogenic and exogenic processes on their weathering and soil formation. Palaeoweathered profile (> 3 m) on Closepet granite (Chitradurga) has been systematically studied based on morphological, micromorphological and geochemical signatures. These resulted in the division of profile in to altered bedrock/protolith (= saprock/lower saprolite) at the bottom (> 250–180 cm) and upper (above 180 cm) regolith profile (= upper saprolite). The regolith profile further consists of lower (i.e. 180–130 cm) grus material and upper (top 130 cm) soil material. The lower saprolite is slightly altered granite, wherein evidences of tectonic stresses and late magmatic processes have been found. Evidences of mechanical stresses due to dominance of endogenic processes suggest formation of granite grus in the lower part of upper saprolite, which paved way for subsequent supergene alteration, i.e. weathering. In the top 130 cm of regolith, significant widening, connectivity and increase in thickness of planar voids as well as illuvial clay to ferruginous coatings and hypocoatings have been observed. This part of profile shows highest CIW (i.e. 80.44) and PIA (i.e. 75.73) values and hydrolysis and leaching values confirm presence of B-horizon. This suggests greater role of surficial (i.e. exogenic) physical and chemical processes. The most diagnostic pedogenic features are illuvial coatings. Further, variation of major and trace elements, trend of REEs in the weathered profile indicate significant pedogenesis in the upper part of regolith. Furthermore, top 25 cm of regolith is more enriched in REEs in comparison to lower part suggesting a possible difference in redox conditions and/or weathering type. [ABSTRACT FROM AUTHOR]

The Early Triassic period was characterised by significant climatic perturbations driven by generally high global temperatures. Several significant shifts in the stable carbon and oxygen isotopes were recognised in the marine settings in the Olenekian age deposits that were linked to short-lasting but relatively high-amplitude climatic events. The record of these events in the continental strata is far less understood due to the stratigraphic incompleteness of such deposits. However, in the Holy Cross Mountains (Poland), the Olenekian continental deposits are well preserved, and sedimentation was relatively continuous, making them an ideal candidate for studying the effects of climate changes and their preservation in continental settings. As such, sedimentological analysis of five wells and one outcrop (over 530 m logged in total), integrated with new and legacy palynological data, allowed the reconstruction and dating of major steps in the palaeoenvironmental evolution of the SE part of the Central European (Germanic Basin), and its comparison with the marine-based climatic models for the Early Triassic. The lower and middle Olenekian stage is represented by fine-grained deposits of dry floodplain interbedded with sandstones deposited within fluvial distributary channels and terminal splays. The palaeosols are mainly represented by aridisols (calcisols), indicating a relatively dry, though not extreme, climate as some water was necessary to support relict plant cover. Towards the mid-Spathian times, the climate became more humid - lacustrine deposits appeared, and palaeosols displayed features of an elevated water table (gleyed vertisols and inceptisols). Frequent storms and floods also affected the lacustrine sedimentation, reflecting volatile climatic conditions. In the late Spathian time, continental sedimentation continued, and the dominance of vertisols and more stacked fluvial channels in the sequence is linked with an increased seasonality, with more pronounced humid seasons. The continental setting lasted until the latest Spathian time, when a marine transgression occurred, marking a new phase in the basin development. • The terrestrial Olenekian deposits were studied for palaeoclimatic reconstruction. • Changes in palaeosols and palynomorphs reflect Early Triassic climatic variability. • A seasonal dry climate dominated Smithian sub-age in the Germanic basin. • A humidification event at Smithian-Spathian/early Spathian times • Mid-Spathian in the Germanic Basin was represented by a highly seasonal climate. [ABSTRACT FROM AUTHOR]

The 2140 01T1 borehole sampling the Late Cretaceous non-marine strata of the Klikov Formation in the central part of the Třeboň Basin in southern Bohemia provided ~ 70 m thick alluvial succession composed of alternating sandstone and mudstone intervals that overlays deeply weathered crystalline basement. The mudstone interval in the lower part of the Klikov Formation is separated by sandy layers into several 2-4 m thick fining-upward units. The sharp-based sandy layers with fusain, carbonized stems and rip-up clasts of underlying mudstone are interpreted as avulsion deposits. They grade upwards into heterolithic sand-silt sequence and mottled massive mudstone with burrows, rhizohalos and variably developed pedogenic features. Such cyclic arrangement probably reflects autogenic processes on distal floodplain with episodic deposition and upward increasing subaerial exposition and pedogenic overprint. In the middle to upper parts of the Klikov Formation up to 6 m thick channel sandbodies with sharp erosional bases cutting into the underlying laminated sand-silt heteroliths of channel levee deposits occur. The thickness of the single-storey sandbodies corresponds usually to c. 2 m which suggests up to 3 m deep channels during bankfull discharge. The thicker multi-storey sandbodies record channel amalgamation on the alluvial ridge or shallow paleovalley fillings. The sandbodies grade upwards to massive mudstones of abandoned channel fills and floodplain deposits. These floodplain units are up to 8 m thick and consist of variegated massive mudstones interrupted by discrete up to 1 m thick fining upward layers of rippled sandstone representing crevasse splay deposits. Depositional context including preserved levee deposits, abandoned channel fillings and floodplain finegrained deposits suggests rather higher sinuosity of the formative rivers. Palaeosol profiles represent pedogenically modified floodplain fines with gradational bases and sharp erosive top surfaces. At least 10 palaeosols were identified in the measured section, forming mostly discrete profiles up to 2 m thick consisting of several B-horizons that differ in the degree of the soil structure development, colour, mottling, grain size, presence of clay hypocoatings and bioturbation index. The most common Bw horizons form lower parts of the profiles and have no or only a weakly developed angular blocky structure (ABS). The typical mottling is caused by a hierarchical system of vermicular greenish-grey reduction rhizohalos, that may be filled by silt to sand or illuviated clay hypocoatings and probably follow the original plant root system. Some patches have diffuse orange rims of iron oxides, probably represented by goethite. Mudstone of Bsst horizons displays well-developed ABS with rare wedge-shaped peds and contains a number of illuviated clay skins and redox depletions. Vertic features like fine cracks filled by sand are common, and slickensides with clay hypocoatings occur rarely. Mudstones of Bt horizons contain a number of illuviated clay hypocoatings filling root channels or interpedal cracks, while the Bss horizons exhibit well-developed ABS with slickensides and contain a number of vertical cracks filled by sandy grains. Palaeosol profiles represent mainly argillisols and vertic argillisols with transitions to argillic vertisols. Poorly developed argillic to vertic protosols are also common. Palaeosol profiles differ mainly in the degree of structural development/maturity, which is given by various lengths of exposition to similar climatic conditions. Vertical distribution of palaeosols reflects their position in the alluvial landscape with locally specific hydromorphic conditions rather than a distinct climatic trend. Most of palaeosols exhibits downprofile translocation of clay (illuviation) leading to the formation of argillic horizon, which typically develop on stabilized landscape in humid climate with seasonal moisture deficit. Seasonal water table fluctuations are also evident from the presence of vertic and redoximorphic features. Rather low evapotranspiration during arid periods indicated by the absence of calcium carbonate accumulation and weakly developed vertic features may most probably reflect short-lived arid seasons. [ABSTRACT FROM AUTHOR]

The McMurray Formation in McMurray Depocentre, Canada, is typically subdivided into stratigraphic units based on regionally mappable marine mudstones, the bases of which define flooding surfaces (bottom to top: Lower McMurray, C2, C1, B2, B1, A2, A1 depositional unit). However, the McMurray Formation comprises a variety of palaeoenvironments, with the north‐eastern Firebag Tributary hosting significant delta‐plain deposits in the Lower McMurray and B1 depositional units. Facies analysis of 60 cores and 4763 wireline logs was used to resolve the palaeoshoreline trajectory and stratigraphic architecture in Firebag Tributary. Of 14 identified facies, three delta‐plain facies reveal: (1) eluviated palaeosols, interpreted as shrublands and woodlands formed during base‐level fall; (2) gleyed palaeosols, interpreted as tidal marshes; and (3) coals formed in coastal mires, the two latter facies are interpreted to accumulate during base‐level rise. Eluviated palaeosols occur below the Lower McMurray coal seam, implying valley incision and a maximum regressive surface. Gleyed palaeosols underlying the coal seam atop the B1 depositional unit do not record base‐level fall. Wetting‐upward coals overlying either palaeosol facies indicate base‐level rise (i.e. major flooding surface). B1 depositional unit coals and gleyed palaeosols are overlain by shallow‐marine facies or are eroded by wave ravinement during transgression. Consequently, the tops of coals or gleyed palaeosols correlate to the bases of regional marine mudstones elsewhere in McMurray Depocentre. Stratigraphic cross sections showcase palaeoshoreline regression and transgression. During the Lower McMurray and B1 depositional units, widespread coals and palaeosols indicate the palaeoshoreline resided near the western edge of Firebag Tributary. Regression during C2 through B2 depositional units and A2 and A1 depositional units resulted in palaeoshorelines near the Alberta–Saskatchewan border. To complement a previously dated Lower McMurray ash (121.39 ± 0.2 Ma), a new high‐confidence maximum depositional age from ash in the B1 coal seam (115.09 ± 0.16 Ma) allows an estimate to be made of depositional duration, indicating depositional units represent ca 0.16 Myr. [ABSTRACT FROM AUTHOR]

The climate in the Altai Mountains is determined by two major climate systems whose dominance has varied over time, leading to significant spatio-temporal changes in temperature and precipitation during the Holocene. This study aimed at the reconstruction of the local to regional moisture and temperature conditions in an alpine belt of the southern Mongolian Altai during the Late Holocene. It thereby contributes to a more comprehensive understanding of the region's palaeoclimate in the Holocene. Our reconstruction is based on palynological and sediment analyses as well as radiometric age determinations of samples from a 130 cm exposed soil/sediment profile within the alpine belt. Largely supported by sedimentological and geochemical observations, the pollen assemblages indicate a warm and dry period between about 2600 and 2250 cal a BP, a subsequent cold and humid phase extending to about 130 cal a BP, and a return to warm and dry conditions lasting to present. Our data support the results of recent studies on the regional climate variability and the observation of significant differences in the mode of climate changes and its temporal sequence within the Altai Mountains. Although the pollen assemblages in the profile reflected a continuous anthropo-zoogenic influence on the study site's vegetation climatic signals were clearly detectable, underlining the indicator value of the pollen data from the Alpine sediments for regional palaeoclimatic reconstruction. [ABSTRACT FROM AUTHOR]

The aeolian sediments in the Central Shandong Mountains (CSM) in eastern China provide a faithful carrier of climate and sea-level variations outside of the Chinese Loess Plateau. However, due to the lack of or limited application of absolute dating protocols, previous studies of Shandong loess have focused mainly on loess deposited since the last interglacial period, with fewer studies on provenances and climate changes recorded in older penultimate interglacial period characterized by a long duration and significant climate fluctuations, which is not helpful to understand the spatiotemporal pattern changes of East Asian monsoon. In this study, multi-elevated-temperature post-infrared infrared-stimulated luminescence (MET-pIRIR) dating method was utilized to obtain the absolute ages from the Dongheishan (DHS) section in CSM region. Preheat plateau and dose recovery tests indicate that the MET-pIRIR signals of 250 °C and 300 °C have negligible anomalous fading and they can give reliable ages for the loess since ∼270 ka. Luminescence dating results suggest that the DHS loess mainly accumulated from 265 ± 12 ka to 93 ± 4 ka. The loess sedimentation rates during ∼195 ± 18–108 ± 4 ka were much lower than expected in the DHS section, which occurred approximately correlates with the Qingshui erosion period (∼136 ka), as indicated by the planation surface outside the CSM. Both the grain-size characteristics and sedimentation rate variations suggest that the dust sources of the DHS loess were primarily proximal sediments, which is possibly due to frequent variations in dust provenances caused by plentiful precipitation during the interglacial periods and diversions of the Yellow River. This study implies that the CSM loess with a good chronology could be utilized to decipher regional sedimentation and climatic changes processes. [ABSTRACT FROM AUTHOR]

• Newly discovered 25 m-thick, ∼2.6 Ga palaeosol on the central Kaapvaal Craton. • Palaeoweathering under reducing atmospheric conditions. • Evidence for early terrestrial life in the palaeosol and overlying base of the Black Reef Formation, Transvaal Supergroup. • Similar occurrence of organic carbonaceous matter in the eastern Transvaal Basin (eastern Kaapvaal Craton) palaeosols. Archaean palaeosols are a rare record of surface processes on the early Earth. We report on the discovery of a palaeoweathering profile developed at the contact between Mesoarchaean basement and the Neoarchaean to Palaeoproterozoic Transvaal Supergroup along the northern margin of the Johannesburg Dome, Kaapvaal Craton. Granodiorite ∼ 3.1 Ga old was subjected to weathering just prior to the deposition of the ∼ 2.6 Ga Black Reef Formation. The ∼ 25 m-thick profile is dominated by a palaeosaprolite and organic matter-rich palaeosol remnant at the top that experienced erosion upon marine transgression on the Kaapvaal Craton. The Al concentration of the profile, sericite content and chemical index of alteration (CIA) values progressively increase from the parent granodiorite towards the nonconformity as Fe, Mg, Na and Ca concentrations decrease. The decrease of Co and Zn together with Fe and the retention of U, V and Cr collectively suggest a reducing and acidic environment at the time of weathering. Carbonaceous matter with negative δ13C isotopic values (−27 to −23 ‰ V-PDB) in the palaeosol is compatible with the former presence of photoautotrophic microbes. Copper depletion and mobility of P may indicate the presence of organic acids that enhanced chemical weathering of the bedrock. The palaeoweathering profile was subjected to diagenetic-hydrothermal K-metasomatism, regional metamorphism and deformation, which collectively transformed the regolith into a quartz-sericite schist, as it presently occurs. Despite these modifications, the original record of palaeoweathering and microbial colonisation is well preserved. Colonisation of a large swath of the Kaapvaal Craton by terrestrial soil-dwelling microbiota at 2.60 Ga is recorded in abundant soil-derived carbonaceous matter in transgressive marine conglomerates that erosively overlie the palaeosol. [ABSTRACT FROM AUTHOR]

Volcanic aquifers supply a substantial portion of water resources in many parts of the world, including islands, and their productivity depends strongly on volcanic stratigraphy, which exhibits considerable heterogeneity. We investigated water inflow to lava tube caves formed from numerous basaltic lava flows in the northeastern coastal area of Jeju Island after storm events and monitored relative inflow rates monthly over 1 year to characterize groundwater flow processes in the upper parts of volcanic aquifers, and to evaluate the applicability of the previous hydrogeological models proposed for the island. Considerable water inflow arose shortly after storms from exposed palaeosol layers on the walls of the caves. The monthly monitoring results showed that wall inflow associated with these palaeosol layers is substantial. In both cases, discharge from ceiling drips was much less and more temporally variable compared to wall inflow discharge. Water flowing into the caves was rapidly drained through the floor at all monitoring sites. The lateral extent of the palaeosol layers was identified using drill core logs near the cave and outcrops in the coastal area. Based on these results, we inferred that multiple perched aquifers are formed by low‐permeability palaeosol layers between lava flows, which are connected by vertical flows at discontinuities in the palaeosol layer, eventually reaching the basal aquifer. This study revealed the water inflow processes observed in lava tube caves constrained by palaeosol layers, and established a hydrogeological conceptual model incorporating multiple perched aquifers in both coastal and mountainous areas associated with extensive palaeosol layers formed during volcanic hiatuses. This finding would help elucidate recharge, groundwater flow, and contaminant transport processes in many volcanic aquifers that are not adequately represented by the previous models, and contribute to better management of groundwater in those areas. [ABSTRACT FROM AUTHOR]

This paper reviews the current state of knowledge about environmental changes at the MIS 3/2 transition in the northern Alps and their foreland, covering the time frame from 35 to 25 ka. Lake and peat deposits, cave sediments, loess and glacial deposits are presented and the response of their biotic and abiotic proxies to climate change is discussed. During late MIS 3, interstadial conditions, albeit weak, occurred at c. 36–32 ka. At climatically favourable sites, small patches of trees (mainly Pinus and some Betula) existed together with some shrubs. The environmental conditions during late MIS 3 are also reflected by a boreal brown soil horizon, a cambisol called Lohne soil, found in many loess sequences. Subsequently, the environmental conditions became harsher as shown by the proxy data. From c. 30 ka onwards the absence of pedogenesis sensu stricto and the plant assemblages point to an Arctic climate in the northern Alpine foreland. Accentuating, glaciers advanced beyond the northern limit of the Alps around the MIS 3/2 boundary and reached their maximum extent in the foreland at about 25 ka. [ABSTRACT FROM AUTHOR]

In the present study, we performed gastropod analyses on loess–palaeosol sequences from northeast Armenia (Southern Caucasia) covering at least three glacial–interglacial cycles. The elaborated ecostratigraphy shows significant patterns of species composition related to the succession of pedocomplexes and loess, respectively. Pedocomplexes included species that can be associated with high‐grass to forest‐steppe biomes, indicating increased humidity for these sections compared to the loess layers. In contrast, loess layers that relate to glacial periods are associated with gastropod species of semidesert environments with shrub‐ and shortgrass‐steppes, indicating semiarid to arid conditions. Furthermore, the loess deposits do not show any evidence for cold‐adapted gastropod species. Therefore, we suggest that average July temperatures in the study area were above 10 °C, even during periods of loess deposition. Consequently, we propose that the limiting factor for tree growth during glacial periods was aridity, rather than temperature. In addition, we observe environmental differences between the various glacial times, with our results indicating a trend towards steadily increasing aridity in Southern Caucasia across the Middle to Late Pleistocene. [ABSTRACT FROM AUTHOR]

The mineral magnetic properties of Pleistocene aeolian dune sands from the island of Fuerteventura (Canary Islands, Spain) were studied in order to reconstruct the palaeoenvironmental evolution of Pleistocene climates during their formation. The palaeodunes on Fuerteventura mainly consist of carbonate sands admixed with dust and material of volcanic origin. Due to the low magnetic background caused by the diamagnetic character of carbonate sands, these archives offer a lot of potential for environmental magnetic studies to detect the imprint of dust, volcanic material and paedogenesis. Four sections of alternating palaeosurface–aeolianite sequences in palaeodune fields have been analysed by means of extensive rock magnetic measurements. These Quaternary archives consist of deposits originating from different sources. I. material blown from the shallow shelf, II. material of volcanic origin, and III. long‐range transported dust. The rock magnetic findings enable a more detailed interpretation of the palaeosurfaces within the sequences. We are able to differentiate semiquantitatively between the different source materials on one hand and to distinguish on the other hand those from soil‐forming processes. Soil formation is only weakly developed in the dust imprints in the palaeosol aeolianite sequences, linked to sparse vegetation cover during the Pleistocene on Fuerteventura. [ABSTRACT FROM AUTHOR]

Abstarct: Jeju Island, which lies on the continental shelf in the southern Korean Peninsula, is the emergent portion of a basaltic volcanic field that has erupted since the Early Pleistocene (ca. 1.8 Ma). Volcanic activity that continued into historic times (ca. 1 ka) formed an elongated shield with a central edifice (Mt. Halla) and more than 300 monogenetic cones and rings. The establishment of a temporal framework for Jeju volcanism, particularly during the Late Pleistocene and Holocene activities, requires geochronological tools other than radiometric dating techniques, which are based on parent-daughter isotope pairs with geologically long half-lives, such as 40Ar/39Ar dating. In this study, we conducted quartz optically stimulated luminescence (OSL) dating of palaeosols intercalated with basaltic lava flows and scoria deposits, presumably ejected from three monogenetic volcanoes (Cheoreum, Darangsh and Dunjibong volcanoes) in the northeastern part of the island. Quartz extracts from the palaeosols had moderate to dim sensitivity to optical stimulation, but several prerequisite tests of the measurement protocols for equivalent dose estimation were successful. The coarse (63–250 μm) and fine (4–11 μm) quartz fractions yielded continuous wave (CW)-OSL ages of 19.9–7.0 and 18.6–6.7 ka, respectively, both of which were broadly consistent with the radiocarbon dates (10245–7440 Cal yr BP). These ages indicate that lava flows and scoria deposits covering the palaeosols are younger than ~7 ka. The pulsed OSL signals in coarse quartz extracts from the palaeosols suffered from poor counting statistics, thus it is recommended that they not be applied solely (i.e., without any other absolute ages to compare) to dating dim samples. From one of the sites investigated here, the averaged sedimentation rate of the palaeosol is estimated to be ~0.05 mm/yr, based on stratigraphically consistent CW-OSL ages. The OSL ages presented in this paper, together with previous OSL and radiocarbon ages, confirm that Jeju volcanic island was regionally active during the Holocene. [ABSTRACT FROM AUTHOR]

Abstract Malacological studies on Middle to Late Pleistocene aeolianite-palaeosurface sequences have been approached in order to detect environmental changes and system shifts on the eastern Canary Islands. Our results reveal that over the last approximately 360 ka, gastropod associations changed fundamentally, allowing the derivation of eight different biozones. The majority of these malacozones and particular species were limited to specific stratigraphic positions and periods. We therefore assume that Quaternary gastropods on Fuerteventura may offer the opportunity to correlate lithostratigraphic units on the basis of key species. Furthermore, environmental conditions could be derived from these associations pointing to colder semi-arid conditions related to the Obelus Zone around 360 to 340 ± 30 ka, a subsequent temperature rise around 340 ± 30 ka leading to moderate and dryer conditions for the Cochlicella Zone , a strong environmental change around 300 ± 30 ka with frequent ephemeral rainfalls for the Pomatias Zone and an increase in temperature and aridity for Late Pleistocene deposits linked to the Rumina Zone. We assume that shifts in malacozonation were triggered by changing climate conditions. Furthermore, the alternation between sand layers and palaeosurfaces is not continuously in conformity with malacozonation. We therefore assume these stratigraphic changes to be not primarily related to climatic forcing, but instead biased by an overlap of multiple factors. As palaeosurfaces indicate favourable conditions (increased gastropod biodiversities and distinct shrub vegetation), we assume that these were caused by increased edaphic moisture due to a better water holding capacity in silty palaeosurfaces, rather than by more humid climate conditions. Highlights • Over the last approximately 360 ka gastropod associations changed fundamentally. • Lithostratigraphic units can be correlated on the basis of key species. • Gastropods can serve as environmental proxies for derivation of palaeo-conditions. • Alternation between sand layers and palaeosurfaces not primarily forced by climate. • Favourable conditions in silty palaeosurfaces may correspond to edaphic moisture. [ABSTRACT FROM AUTHOR]

Abstract The Late Pleistocene loess-palaeosol sequence in Tyszowce (Sokal Plateau-Ridge, SE Poland) has been analysed for major elements (Si, Na, K, Mg, Ca, Fe, Mn, Al, Ti and P) in order to determine its chemical composition, stratigraphy and degree of chemical weathering. For the investigation, a total number of 85 loess and soil samples were tested. The vertical differentiation of chemical composition is strongly correlated with the variability of pedo- and lithostratigraphic units. The loess-palaeosol sequence in Tyszowce is geochemically distinct from other loess presented in the worldwide literature. The profile is generally enriched with silica while other chemical elements are relatively depleted. The contents of the major elements, except Si, are lower in relation to the Global Average Loess (GAL) composition. Weathering indices, such as Chemical Index of Alteration (CIA) or K/Al molar ratio and A-CN-K diagram, imply weak to moderate weathering of the source material. [ABSTRACT FROM AUTHOR]

Abstract The numerous discoveries of disintegrated skeletons of large terrestrial vertebrates within several thin levels of the Upper Silesian Keuper initiated broad investigations into the palaeoenvironment and age of the bone-bearing sediments. Despite years of research, the depositional history of the Upper Triassic continental succession and its controlling factors are still poorly recognized. This paper reconstructs the depositional evolution of the Upper Triassic strata in Upper Silesia, Poland, discusses the tectonic and climatic control on deposition, and identifies the sediment provenance. Detailed sedimentological analysis enabled the recognition of three major palaeoenvironments: (1) playa; (2) distal floodplain featured by gilgai micromorphology; (3) fluvial system (sand-dominated meandering, sand- and gravel-dominated braided, and potentially anastomosing river system). The transition from one palaeoenvironment into another reflects climatic changes throughout the late Triassic. The Carnian interval is dominated by gypsum-rich playa mudstones deposited under hot and arid conditions, with only one wet episode recorded as meandering river sandstones (the so-called Carnian Pluvial Event). In contrast, Norian sedimentation was controlled by strong seasonal climatic variations, which is reflected in alternating palaeosol horizons (vertisols and calcisols), thin claystone beds (small water-pond deposits), and conglomerates (rapid flood events). This facies assemblage was formed in a relatively stable floodplain which became the main habitat of numerous vertebrate organisms. The Rhaetian is represented by a gravel-dominated braided river system developed in response to significant climate humidification, with tectonic controls on flow direction. Clast types from Norian and Rhaetian conglomerates revealed that the studied area was fed from the south and south west by the San River and Moesian Massifs. Geochemical analysis of Norian palaeosol horizons suggests mean annual precipitation of ~720 mm/yr in agreement with the palaeoclimatic reconstructions for the area, pointing to seasonal sub-humid to semi-arid climate conditions. Highlights • Carnian-Norian terrestrial deposits from SE Germanic Basin represent playa and gilgai-type floodplain environments. • The evolution of gilgai environments was mainly controlled by climatic changes through Late Triassic. • Gravel analysis indicates San River and Moesian platform sources. • Palaeosol type and geochemistry indicate climatic seasonality with precipitation at 720 mm/yr. [ABSTRACT FROM AUTHOR]

The appearances of palaeosurfaces intercalated into palaeo-dune fields on Fuerteventura are multifaceted. Although reddened layers in these dune sediments might suggest that strong soil-formation processes have taken place, the combination of aridity and parent material, namely biogenic carbonate sand of shelf origin, reveals that strong soil formation seems unlikely. These sediments rather represent de- and recalcification processes only. Solely in the case of admixed material of volcanic origin and dust deposits further soil-forming processes seem to be possible. Hematite-rich Saharan dust contributes to reddish colouration of the palaeosurfaces. In addition, CaCO3-coated iron particles appear to be ingredients of dust being leached after deposition and transformed to hematite. Overall, we propose much weaker soil-forming processes during the Pleistocene than previously postulated. Our findings support the relevance of local environments. Carbonate sands of shelf origin hinder strong soil formation and the reddish layers separating dune generations are palaeosurfaces, which mainly consist of Saharan dust. After deposition of allochthonous material, these layers are overprinted by weak soil-forming processes. The formation of palaeosurfaces primarily depends on morphodynamically stable periods during limited sand supply. Our data suggest a cyclicity of processes in the following order: (1) sand accumulation, (2) dust accumulation and weak soil formation, and (3) water-induced erosion. For the Canary Islands, we support the assumption of glacial maxima being periods of increased levels of moisture. In combination with rising sea level, we propose that favorable conditions of surface stability occur immediately after glacial maxima during periods of starting transgression, whereas regression periods immediately after sea-level high stands seem to yield the highest sand supply for the study area. [ABSTRACT FROM AUTHOR]

In the focus of this study are the sedimentary characteristics, chronology, magnitude, and causes of past soil erosion dynamics of an agriculturally intensively used glacial lowland landscape. From the mesoscale Quillow river catchment, sedimentary sections bearing colluvial sediments from different landforms were analysed to explore their geoarchive potential and to establish a local chronology of Late Holocene soil erosion. Sections from footslopes contain a rather simple stratigraphy with one topping colluvial horizon of up to 1 m thickness burying a palaeosol. In contrast glacial kettle holes preserve more complex sequences partly having several colluvial layers with intercalating palaeosols. The most complex stratigraphy is associated with a kettle hole being the ultimate sediment trap for a dendritic gully system, forming a 4 m thick sequence of alternating peat and colluvial layers. Thirty OSL ages and 13 radiocarbon ages are used to reconstruct phases of soil erosion. Potentially human-induced soil erosion, which is corroborated by local archaeological and palynological data, can be traced back to the last c. 4000 years. The oldest colluvial deposits date back to the Late Bronze Age. Most datings, however, cluster within the last 600 years with a peak in the last 200 years, ascribing the main phase of local soil erosion to the recent past. Thus, although numerous archaeological finds are detected in the catchment since the Neolithic, considerable agricultural soil erosion does not occur before the last millennium. A compilation of OSL chronologies based on colluvial sediments from other regions in Central Europe shows a more complex erosion history there with a pronounced two- or three-phased distribution of ages primarily dating into the last c. 4000–5000 years. This study underlines that in northeastern Central Europe human impact on landscapes was effective apparently at a later stage as compared to some adjacent regions. [ABSTRACT FROM AUTHOR]

Loess-paleosol series are well preserved in the south part of the Russian Plain. However, these sequences have a low number of studies on their organic matter, such as researches of isotope composition, n-alkane and other biomarkers. Thus, the purpose of the study was to reconstruct vegetation conditions from the Late Glacial to Late Holocene. We used the leaf wax-derived n-alkanes to detect vegetation evolution of the Bryansk Region. The stable carbon isotope composition of organic matter and pedogenic carbonates was carried out for the same aim. Three paleosols (of Lasko, Bølling-Allerød warmings and Holocene second humus horizons) and modern soils of different relief positions were investigated. n-Alkane distribution, as well as isotope composition indicates changes from grassy to woody vegetation during this period. The use of biomarkers such as n-alkanes helps to more clearly interpret isotopic data.

Contents531I.531II.532III.534IV.535V.535VI.535Acknowledgements536References536 Summary: There is growing evidence that life has been on land for billions of years. Microbial mats fuelled by oxygenic photosynthesis were probably present in terrestrial habitats from c. 3.0 billion yr ago (Ga) onwards, creating localized ‘oxygen oases’ under a reducing atmosphere, which left a characteristic oxidative weathering signal. After the Great Oxidation c. 2.4 Ga, the now oxidizing atmosphere masked that redox signal, but ancient soils record the mobilization of phosphorus and other elements by organic acids in weathering profiles. Evidence for Neoproterozoic ‘greening of the land’ and intensification of weathering c. 0.85–0.54 Ga is currently equivocal. However, the mid‐Palaeozoic c. 0.45–0.4 Ga shows global atmospheric changes consistent with increased terrestrial productivity and intensified weathering by the first land plants. See also the Commentary on this article by Friedman, 215: 505–507. [ABSTRACT FROM AUTHOR]

Loess-palaeosol sequences preserve the most important continental record of climatic and environmental changes during the Quaternary. As a significant element of global geodiversity and geoheritage, loess-palaeosol sequences could be used as resources for a contemporary trend in sustainable tourism – geotourism. This form of tourism appreciates and promotes non-living nature (geodiversity) through its conservation and interpretation. This further leads to enhancing public awareness of these sites. In this study, we report on a proposal for establishing geotourism at the most important loess sites in the Vojvodina region.

Closed depressions are reported in loess landscapes in various parts of Europe. The anthropogenic and natural origin of closed depressions is highly debated in literature. Closed depressions are an important component of the landscape in loess areas of the Lublin Upland. Furthermore, they perform the role of local closed sediment basins, creating unique conditions for the preservation of soils and colluvial sediments, along with the record of the evolution of the Holocene landscape, occurring under the influence of climate changes and human activity. The study objective was to evaluate the contribution of natural and anthropogenic processes influencing the origin and evolution of closed depressions. The Nałęczów Plateau is composed of loess, whose thickness varies from a few meters to > 30 m. 1761 closed depressions have been documented within the Nałęczów Plateau (493 km 2 ). A detailed investigation was conducted within selected closed depression, dissected by a deep and long road trench. The studied form was 40 m long, 26 m wide and 0.7 m deep. The analyzed exposure; 20 m long and 7 m high, presents a cross-section of the closed depression. Fieldwork and subsequent laboratory analyses were conducted: morphological, micromorphological, microstructural, geochemical, physico-chemical, OSL and 14 C dating. Archaeological and historical correlations were also performed. The primary bottom and slopes of the studied depression are composed of loess in situ, overlain by Late Glacial-Holocene fossil soil. Periglacial structures, such as deformed ice-wedge pseudomorphs, cracks and lenses macro-structures were documented in the loess and palaeosol at the bottom of the closed depression. The depression is filled with Neoholocene soil-sediment sequences consisting of 2 layers of colluvial sediments, separated by Neoholocene subfossil soil. They constitute a record of the two stages of CD infillings in the Holocene, connected with human agricultural activity, lasting from the Neolithic up to modern times. A detailed analysis of the loess, Late Glacial-Holocene fossil soil and Holocene colluvial sediments made it possible to distinguish the stages of evolution of closed depression influenced by changing environmental conditions and human activity, during the Late Glacial and Holocene. [ABSTRACT FROM AUTHOR]

In Northern Iran mean annual precipitation and vegetation vary significantly over short distance from a semi-desert to a forest biome. These ecosystems likely responded differently on past climate changes. We here aim at i) testing the applicability of biomarkers (leave-derived n-alkanes, their stable carbon isotope composition, and C and N stable isotopes of soil organic matter) in loess-derived soils to identify and differentiate past ecosystems, and ii) elucidating the variability of these biomarkers in palaeosols. We sampled modern topsoils and palaeosol horizons within an ecological gradient covering a range in mean annual precipitation from 200 to 750 mm from the Kopet Dag semi-desert to the Hyrcanian forest on the footslopes of the Alborz Mountains. C org , N, δ 13 C org , δ 15 N, and n-alkanes (and their compound-specific δ 13 C) were analyzed to characterize organic matter composition and sources. In modern soils a systematic increase in C org and N was observed with precipitation. The δ 15 N decreased from about 6 to 4‰ pointing to systematically more degraded organic matter in semi-desert soils. The leave-wax specific ratio of (nC 31 + nC 33 )/(nC 27 + nC 29 )-n-alkanes was >1 for semi-desert soils and <1 for the forest ecosystem. The δ 13 C org showed no systematic trend in this gradient. In loess and palaeosol profiles, contents of C org , N and n-alkanes dropped about a factor 10 compared to modern soils. The n-alkane ratio and δ 15 N ratios remained on comparable levels as did the compound-specific δ 13 C in n-alkanes. However, bulk δ 13 C org was altered from about −27 in modern soil to −23‰ in loess-palaeosols. Systematically higher C org and N values were observed in palaeo-topsoils compared to loess and subsoil. Stable C isotopes varied rather unsystematically within loess-palaeosol sequences, while δ 15 N revealed trends within palaeosols, however, in contrasting directions with palaesol depth. The (temporal) average n-alkane ratio for all palaeosol horizons of one site systematically followed the modern precipitation gradient indicating that in all periods of soil formation a climatic gradient developed. [ABSTRACT FROM AUTHOR]

The article presents the comparison of the geochemical composition and the degree of chemical weathering between two Late Pleistocene loess-palaeosol sequences of SE and SW Poland. The results of major element (Si, Al, Fe, Mn, Mg, Ca, Na, K, Ti, P) and geochemical index (CIA, Ti/Al, K/Al, Mg/Ca, K/Ca, Na/K oraz Si/Al) analyses indicate stratigraphical and spatial differentiation between sequences. The stratigraphic differentiation is connected with palaeoclimatic conditions which control the intensity of pedogenesis. The spatial variability may be attributed to different climatic conditions during the deposition of loess, the loess recycling process, or even to different source areas. The disproportion between the thicknesses of the loess covers can also be important. It can affect the rainwater infiltration effect. [ABSTRACT FROM AUTHOR]

Flood-generated sandy siltstones are under-recognised deposits that preserve key vertebrate (actinopterygians, rhizodonts, and rarer lungfish, chondrichthyans and tetrapods), invertebrate and plant fossils. Recorded for the first time from the lower Mississippian Ballagan Formation of Scotland, more than 140 beds occur throughout a 490 m thick core succession characterised by fluvial sandstones, palaeosols, siltstones, dolostone 'cementstones' and gypsum from a coastal-alluvial plain setting. Sandy siltstones are described as a unique taphofacies of the Ballagan Formation (Scotland, UK); they are matrix-supported siltstones with millimetre-sized siltstone and very fine sandstone lithic clasts. Common bioclasts include plants and megaspores, fish, ostracods, eurypterids and bivalves. Fossils have a high degree of articulation compared with those found in other fossil-bearing deposits, such as conglomerate lags at the base of fluvial channel sandstones. Bed thickness and distribution varies throughout the formation, with no stratigraphic trend. The matrix sediment and clasts are sourced from the reworking of floodplain sediments including desiccated surfaces and palaeosols. Secondary pedogenic modification affects 30% of the sandy siltstone beds and most (71%) overlie palaeosols or desiccation cracks. Sandy siltstones are interpreted as cohesive debris flow deposits that originated by the overbank flooding of rivers and due to localised floodplain sediment transport at times of high rainfall; their association with palaeosols and desiccation cracks indicates seasonally wet to dry cycles throughout the Tournaisian. Tetrapod and fish fossils derived from floodplain lakes and land surfaces are concentrated by local erosion and reworking, and are preserved by deposition into temporary lakes on the floodplain; their distribution indicates a local origin, with sediment transported across the floodplain in seasonal rainfall episodes. These deposits are significant new sites that can be explored for the preservation of rare non-marine fossil material and provide unique insights into the evolution of early terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

In Belgium, two areas show extended Late Pleistocene loess cover: the Hesbaye close to Liège and the Haine Basin around Mons. For decades, correlation between both areas remained problematic. Here we will show how, by way of complementary approaches, the records of the Haine and the Hesbaye could be inserted into a high resolution pedosedimentary sequence encompassing the major part of the Late Pleistocene and reproducible at the scale of the Belgian loess belt. Based on the pedosedimentary and palaeoenvironmental signatures of the Belgian sequence, comparisons are proposed with high resolution loess sequences of Eastern Europe and Central Siberia. They give access to well documented palynological data for the first part of the Late Pleistocene and to a strong climatic record on loess framed between 45 and 10 ka BP by long series of radiocarbon dates on charcoal and wood remains. The conjunction of these complementary loess records has further given way to a consistent proxy-correlation scheme linking a high resolution continental climatic record to the Greenland ice sequence. [ABSTRACT FROM AUTHOR]

Late Quaternary alluvial sedimentary units in the Guadiana Menor River valley, a tributary of the Guadalquivir River in southern Spain are described based on geomorphological mapping, sedimentological analysis, palaeosol development, and radiocarbon chronology. Four infill units in the valleys were differentiated with surfaces at + 45 (MU1), + 70 (MU2), + 8–6 (MU3), and + 10 m (MU4) above the riverbed. Each unit is capped by a palaeosol. Unit MU1 (Late Pleistocene: > 43.5–34 cal kyr BP) consists of gravel and sand in channels and bars in braided river systems distally evolving to silty clays in the floodplain with vertic and clayic calcisols. It is capped by dark clays with gleysol development representing wetland environments in endorheic basins. Channelized gravels alternating with sandy silts make up unit MU2 (34–24 cal kyr BP), capped by a gypsisol and interpreted as a semi-arid alluvial fan distally evolving to playa-lake depositional systems. Unit MU3 (5600–2700 cal yr BP), extending along the valley bottom, is represented by gravels and sand distally evolving to a red and white laminated rhythmite of silt and clay deposited in the playa. Unit MU4 (600–700 cal yr BP) is scattered and represented by centimetre-thick gravels and sand sheet layers deposited by sheet flows in semi-arid constrained alluvial fans. Alternating intervals of alluvial aggradation (> 43.5–24 kyr BP, 5700–2700 cal yr BP, Late Middle Ages) and fluvial incision (24–6 cal kyr BP, 2700 cal yr BP to 1200 AD, 1500 AD to present) are interpreted as valley responses to climate variations and changes in land use. Two regional geomorphological changes are recorded in the sediments: (1) climate-induced aridification after 34 cal kyr BP with an arid climax after 24 cal kyr BP before the incision linked to the last glacial period, and (2) two human-forced aggradation stages (5600–2700 cal yr BP and 1200–1400 AD) interrupting the Late Pleistocene to Early Holocene incisional trend. [ABSTRACT FROM AUTHOR]

Terrestrial sediments are a significant archive of past conditions, and the 'critical zone' in particular is important for understanding past and ongoing interactions between the atmosphere, biosphere and lithosphere. Understanding the details of a palaeolandscape or palaeocatena record can greatly improve palaeoenvironmental descriptions and palaeoclimate reconstructions during crucial time periods in the past. This article presents multi-proxy data including palaeosol descriptions, major element geochemistry, magnetic composition and stable isotope geochemistry from an early Eocene palaeosol transect, which show distinct trends in palaeosol features and geochemistry across the landscape, particularly in terms of the differences between A-horizon and B-horizon samples. A-horizon geochemical and physical features are highly variable and reflect other not strictly pedogenic controls, whereas B-horizon composition is extremely consistent. Given that most palaeoclimatic or palaeoenvironmental proxies based on palaeosols use B-horizon features, these results highlight the robustness of those proxies. At the same time, the difference between A-horizons and B-horizons and the variability within A-horizons of the same palaeosol in different geomorphic settings underscores the importance of palaeosol description, detailed sampling, and a multi-proxy approach to produce both precise and accurate reconstructions of past environments and climates using terrestrial sedimentary records. [ABSTRACT FROM AUTHOR]

Ten samples of loess and palaeosols collected from the Costinesti–Dobrogea (Romania) loess deposit and covering a time span of about 690 ± 90 ka were analyzed by X-ray diffraction, Instrumental Neutron Activation Analysis and X-ray Fluorescence in order to determine the origin as well as the climatic conditions during loess deposition. The presence of illite and calcite suggests reduced weathering, confirmed by climate proxies. Chemical Index of Alteration (54.6–64.0), Chemical Index of Weathering (65.7–71.7) and Rb/Sr (0.26–0.47) were lower than the neighboring Hungarian loess, but closer to the average loess. The content of 28 trace elements, including 10 REE, confirmed an average rock composition close to the Upper Continental Crust. The elevated content of Cr and Ni indicated the presence of a certain amount of felsic rock material. Zr and Hf whose content was more than twice that of the Upper Continental Crust indicate significant sediment sorting. The low values of climatic proxies as well as the absence of any statistical significant difference between loess and palaeosol material confirmed rather limited weathering during the formation of the south-eastern Dobrogea loess deposits. [ABSTRACT FROM AUTHOR]

The knowledge of palaeoclimate in Iran is still limited. However, insight into the timing and the dynamics of Quaternary climate change in Iran might offer valuable information to improve the global palaeoclimate record. The loess-soil sequence of Toshan provides the first high-resolution record of late Pleistocene climate dynamics in Iran and complements the hitherto known sections at Neka, Now Deh and Agh Band to establish a pedostratigraphic record of the north-eastern Caspian Lowland. Our spectroscopic and grain-size analysis are combined to propose (i) a pedostratigraphical scheme for the sequence at Toshan, (ii) describe and estimate the degree of soil development of selected stratigraphical units, (iii) infer palaeoclimatic information, and provide (iv) a correlation with previous loess-palaeosol records of N-Iran as based on pedostratigraphic assumptions. The section at Toshan hosts a strongly developed reddish-brown argillic palaeosol (Bt) as well as eight moderately to weakly developed brownish palaeosol horizons lacking clay illuviation features (Bw/Bwk). These remnants of fossil soils are separated by finely textured loess and horizons that host characteristics of both loess and mineral subsoils (CB/CBk), giving evidence for syngenetic soil formation. The stratigraphical succession of palaeosols, loess and syngenetically altered sediments, covering the last ca. 130 ka, gives evidence for recurrent climate changes as well as fluctuations between dominance of soil formation or dust accumulation in relation to changes in moisture regime. The formation of Bt and Bw/Bwk-horizons is related to relatively humid and warm conditions likely corresponding with interglacial and interstadial climate. [ABSTRACT FROM AUTHOR]

The distribution pattern of barite in large (15 × 10 × 5 cm) undisturbed aggregates of calcite/clay laminae from a Petric Durisol was investigated using micro-computerised tomography (micro-CT). The petroduric horizons are part of truncated palaeosols which have formed in the Vaalputs sediments located in the Northern Cape Province of South Africa. In these soils clay and calcite laminae encase large polygonal petroduric units. The distribution pattern of barite in relation to the calcite/clay laminae can be used as an indicator to determine the sequence of barite and calcite formation. Samples from two typical profiles were collected for micro-CT analysis. The 2D and 3D visualisation of undisturbed aggregates show an intricate vein network of barite, which runs in a predominantly vertical direction. The barite is intimately associated with the calcite/clay laminae and largely follows the topography of the wavy laminae. In certain instances, along the interface between the petroduric matrix and the laminae, the barite accumulations appear to have wedged the laminae apart. This, together with the unlikelihood that the intricate vein networks of barite would be able to remain intact during the crystallisation of calcite, suggests that barite accumulation in the laminae occurred at the same time or after the calcite laminae were formed. [ABSTRACT FROM AUTHOR]

A large part of Les Garrigues (Western Catalonia) is occupied by stone terraces (locally known as bancals ) that were built up in the 18th century. Some soil surveys of the area noted the presence of buried, thick A horizons with a well developed crumb structure and darker colour than the present-day A horizons. The objective of this study was to determine the conditions of the soil cover both at the time of the formation of these buried soils and at the onset of terracing. The climate is semi-arid and the landscape is defined by platforms and flat-bottomed valleys. Four profiles were described from both slope and valley-floor terraces and sampled for analyses. A buried Ahb horizon appears at various depths between 40 and 180 cm, with thicknesses ranging from 35 to 160 cm, probably due to earthworks since this depends on the position of the profile within the terrace. Many of these buried soils would correspond to Phaeozems: they are identified by an Ahb having low values and chromas (usually 4 or less), a structure due to faunal activity (100% of the structural forms related to fauna either in the form of empty or infilled channels, vermic qualifier), and an organic matter content that is 1.7–3.3%, which is higher but not significantly different than the SOM content of the present day topsoils. P (Olsen) is 1–6 ppm. The present soils are non-saline and highly calcareous (> 40%), they show some calcium carbonate redistribution in the form of pseudomycelia, and biogenic calcite. Charcoal is present in some of these buried horizons, together with small ceramic fragments. These buried horizons have several common micromorphological features: a spongy, highly porous structure due to high faunal activity, frequent silt cappings, charcoal fragments, and biogenic carbonates (queras). In some cases the biogenic calcite has undergone dissolution and reprecipitated as micrite. Pollen assemblages of the buried horizons reveal a large forest cover mainly of oaks and pines, which is also corroborated by the occurrence of Quercus phytoliths; but the presence of pollen of some deciduous crops (such as cereals, Vitis vinifera and Olea europaea .) at the top of the sequences points to a Upper Holocene origin of these soils. The results from the charcoal study support the presence of perennial Quercus and pines as well as shrubs in the period when the terraces were built. The available information about present day similar soils indicates that the formation of these horizons took place under a moister, milder climate in the past, compared with the present one in the study area. [ABSTRACT FROM AUTHOR]

As significant indicators of deep-time palaeoclimate, a number of new palaeontological, pedological and geochemical characteristics are provided for the Chemnitz Fossil Lagerstätte to depict more precisely its environmental conditions. For the first time, several lines of evidence indicate that this fossil forest, instantaneously preserved by volcanic deposits, once received an annual precipitation of around 800–1100 mm, but grew on a nearly unweathered palaeosol. Although the composition of this rich and diverse T 0 assemblage suggests a hygrophilous, dense and multi-aged vegetation dominated by conservative lineages, the habitat was affected by environmental disturbances and pronounced seasonality. Repeated changes in local moisture availability are suggested by geochemical proxies, the co-occurrence to intergrowth of calcic and ferric glaebules in the palaeosol and developmental traits of perennial vegetational elements. Specific substrate adaptation is reflected by different root systems and cyclic growth interruptions recorded in the stems, branches and roots of long-lived woody plants. Many differentially adapted terrestrial animals complete the more comprehensive reconstruction of a late Sakmarian ecosystem and its climatic and preservational controls. Albeit spatially confined, this diverse in-situ record may contribute to understand wetland–dryland dynamics of sub-tropical Northern Hemisphere Pangaea. [ABSTRACT FROM AUTHOR]

The method of quartz optically stimulated luminescence (OSL) dating is widely used, but generally limited to the past ∼0.1 million years (Ma) due to early saturation of the desired signal. Violet stimulated luminescence (VSL) of quartz has previously been shown as a promising alternative, with a dose saturation level ∼20 times higher compared to that of OSL, excellent thermal stability on the 10 11 year time scale, and agreement between VSL and OSL ages up to ∼0.3 Ma. Here we explore the usability of the VSL signal to date older quartz samples from palaeosols, whose ages are bracketed by K–Ar ages and palaeomagnetic data of the interbedded basalts, emplaced between 1.6 and 0.7 Ma. VSL ages from three palaeosols largely underestimate the independent ages of their overlying basalts. This can be explained either by a low-temperature thermal anomaly resetting the VSL signal in nature, and/or by an insufficient measurement protocol, unable to correctly translate the natural signal into the equivalent laboratory dose. [ABSTRACT FROM AUTHOR]

Pocket penetrometer measurements, though commonly listed as accessory components of core descriptions, are almost totally ignored in shallow subsurface stratigraphic analysis. In this study, we prove that, if properly calibrated with core data, pocket penetration tests may serve as a quick and inexpensive tool to enhance high-resolution (palaeosol-based) stratigraphy of unconsolidated, late Quaternary non-marine deposits. A palaeosol sequence, made up of 12 vertically stacked, weakly developed palaeosols (Inceptisols) dated to the last 40 ky cal BP, is reconstructed from the subsurface of the southern Po Plain. The individual palaeosols exhibit flat to slightly undulating geometries and several of them can be tracked over distances of tens of km. They show substantially higher compressive strength coefficients than all other fine-grained, alluvial (floodplain) facies, being typified by distinctive penetration resistance, in the range of 3.5-5 kg/cm2. Along the palaeosol profiles, A and Bk horizons demonstrate consistent difference in relative compressive strengths, the highest values being almost invariably observed at the A/Bk boundary. Palaeosols are rarely described in conventional stratigraphic logs, and just a small proportion of them is likely to be identified by geologists with no specific sedimentological training. Through core-log calibration techniques, we document that vertical profiles of penetration resistance measured in the field can be used as an efficient method for palaeosol identification, and thus may represent a strategy for predicting stratigraphic architecture from limited core descriptions or poor-quality field logs. This technique allows to optimize the contribution of all available stratigraphic information, expanding significantly the coverage of well-described, one-dimensional core data. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Fossil soils and pedosediments displayed in Quaternary fossil-bearing formations are an important proxy to describe the evolution of climates and environments. Through a study of the palaeosols in the Sangiran dome, a rich hominid-bearing site of central Java (Indonesia), we characterized their record of terrestrialization through regional volcano–tectonic activity and describe palaeoenvironments colonized by hominids. The thick sedimentary formations of the Sangiran dome are known to reflect the geological evolution of Central Java from the beginning of the Quaternary until the Middle Pleistocene. Homo erectus fossils are found in the ca. 1.5 Ma Sangiran (or Pucangan) Formation up to the ca.0.8 Ma Bapang (or Kabuh) Formation. This study combines field surveying, a micromorphological approach, and palynological data. The characterization of successive pedoclimatic contexts and toposequences helps in reconstruction of the local palaeogeography and climates (mainly influenced by south-eastern Asia monsoon cycles) that predominated during periods of palaeosol development. The base of the Upper Sangiran member displays the earliest fully continental deposits, corresponding to the development of an open landscape with wide coastal marshes and mangroves, with a rain forest cover on the hinterland. Higher in the stratigraphic succession, environments reflect a contrasting seasonal climate with a long dry season alternating with periods of more humid palustrine conditions. A further tectonic uplift of the hill ranges bordering the Solo depression (in which the Sangiran dome is located) resulted in topographic changes and increasing palaeogeographic heterogeneity, and therefore of soilscapes. From the Upper Sangiran member to the Bapang lower member, erosion of soil cover caused the accumulation of pedosediments in topographic depressions. These pedosedimentary deposits as well as volcanic ash accumulations were sudden and sometimes bury palaeoreliefs (catena, gilgai). Recurrent aridity proxies occur in the palaeosols found in the Bapang formation (which yielded the most numerous hominid fossils), reflecting a long dry season and an open vegetation landscape. [ABSTRACT FROM AUTHOR]

Organic-rich sediments are exposed at a number of onshore and nearshore sites along the Baltic Sea coast of the Curonian Spit. Radiocarbon dating of relict tree stumps, as well as buried and reworked peat and palaeosols, found along the Russian part of the Curonian Spit (villages of Lesnoy and Rybachy) and in the vicinity of Zelenogradsk indicate the formation of these sediments over a wide time period from 7300 cal BP to 300 cal BP. Organic-rich sediments of different stages of the Holocene sand barrier evolution are of interest in terms of environmental protection, as potential accumulators of oil (or other hydrocarbon) pollution and indicators of intensity of coastal erosion. In terms of geochronology, the data have implications for reconstructing the geological history of the Curonian Spit and Curonian Lagoon during the Late Pleistocene and Holocene. [ABSTRACT FROM AUTHOR]

• Seven continental and basinal sedimentary facies associations in Ediacaran of Baltica. • Hot and humid Ediacaran climate on Baltica. • Mineral authigenesis widespread in both proximal and distal environments. • Tropical, disoxic conditions in the Ediacaran indicated by berthierine. • Marine oxic conditions in the Cambrian indicated by glauconite. Mineralogical and geochemical compositions of mudstones were used for untangling provenance and climatic signals preserved in the upper Ediacaran - lower Cambrian strata from the western part of the East European Craton (ECC). Quantitative mineralogy and geochemistry data were obtained for 735 argillaceous rock samples from 71 wells and outcrops and compared with the analyses of Proterozoic palaeosols from the same area. Additionally, sedimentological analyses of well-preserved cores were performed to reconstruct predominant Ediacaran and early Cambrian environments. Seven major facies associations were distinguished and interpreted as both continental and basinal in nature. Terrestrial environments include weathering crust, alluvial fans, and associated interlobe areas, fluvial channels, floodplains, and lakes. Transitional environments are represented by tidal lithofacies, whereas central bay and upper offshore facies associations are typical of distal deposits. The central basin area is interpreted as an estuary opening toward the east, while a separate basin developed in Podillya. Provenance heavily influenced the mineralogical and geochemical characteristics of the sediments and affected derived weathering indices. The change from mafic to felsic sources in the western ECC is evident towards the Cambrian. All geochemical and newly introduced mineralogical weathering indices show advanced kaolinite-type weathering, evidence of a hot and humid climate during this interval. Based on these indices, mudstones are weathered to a greater extent than palaeosols. This observation is interpreted as resulting from the redeposition of highly weathered topsoils, combined with additional weathering on-route to the basin. Mineral authigenesis (berthierine, pyrite, goethite, fluorapatite, and carbonates) was particularly intensive in the terrestrial interlobe areas. Berthierine is common in most environments, which reflects the reaction of kaolinite with iron oxides, mediated by microorganisms, in shallow dysoxic tropical waters, with high lateritic sediment input. Marine, more oxic conditions in the Cambrian are indicated by a pervasive appearance of glauconite. [ABSTRACT FROM AUTHOR]