Interglacial Soil Research Articles

Late Pleistocene chronology of loess deposition near Luochuan, China

Loess near Luochuan was sampled for thermoluminescence (TL) dating simultaneously with magnetic susceptibility measurements to provide the first independent age estimates on a susceptibility record from the Loess Plateau of China. TL age estimates on late Pleistocene loess (L1) are stratigraphically consistent with no statistical difference in TL ages by the total or partial bleach techniques or by measuring ultraviolet or green wavelengths in the TL analysis. Loess below the last interglacial soil (S1) yielded disparate results and is in many localities in central and eastern China unsuitable for TL dating because of complications of TL saturation and uncertainties in estimating the environmental radiation. TL age estimates on the L1 loess are consistent with previously reported TL ages for sites near Beijing and Xian as well as in general agreement with age models for loess deposition based on paleomagnetics and magnetic susceptibility. The convergence of a variety of geochronologic indices indicate that the last major period of loess deposition in central China began 70,000 ± 10,000 yr B.P. and terminated <20,000 yr B.P. This event is probably recorded in sediments from the adjacent Pacific Ocean and possibly in dust records from the Antarctic Ice Sheet.

The loess of West Europe

During the last thirthy years, many studies about loess and periglacial deposits have allowed to present a correlation table from the Netherlands and Belgium to north-west France. For the Quaternary, 11 main interglacial soils were recognized, separated during Early Pleistocene by combe-rock and solifluction deposits, and during Middle and Late Pleistocene by loess cycles. Two main loess basins exist in France. The most important is the Northern basin, continuing the sandy area of Belgium (cover sand) and the desert pavement of the Netherlands. The second is developed in Normandy and results from the Channel “landscape” open during pleniglacial periods. We have now stratigraphic tables at different time-scales. The main research axes must be now to attain a better knowledge about sources of loess materials, to estimate the volume of loess and its climatic significance and landscape variation during the pleniglacial events. Absolute datings of Middle Pleistocene stratigraphic details are needed to evaluate the differences between the different climatic cycles.

Loess-paleosol formation on the Russian plain

The East European loess province is the largest one not only in the Northern Hemisphere, but also on the Earth. The chronostratigraphic scheme for this province was worked out on the basis of data obtained by different research methods. Accumulation of loess like deposits began at the end of the Pliocene in the post-Akchagilian time. Deposition of silt material and loess formation began in the second half of the Eopleistocene. During this period up to the Holocene (about 1 Ma), 6 interglacial soil complexes can be identified. According to paleomagnetic data the Brunhes-Matuyama boundary occurs within the Don Loess, which corresponds to maximum (Don) glaciation of Eastern Europe. The composition of the loess-paleosol complex of the Middle Pleistocene is much more complicated; there are 3 interglacial soil horizons overlain by the Middle Pleistocene moraine of the Dnieper glaciation. A well-developed interstadial soil horizon (Bryansk Soil) can be distinguished within the Late Pleistocene formation (32-26 ka BP). The structure of the loess-paleosol complex varies over different regions of the East European loess province. These differences can be shown on a new type of map: that of loess-paleosol chronocomplexes.

Le pédocomplexe de Warneton, Ou en est-on ? Bilan paléopédologique et micromorphologique.

The Waraeton pedocomplexe essentially consists in a humic lithofacies, located at the top of the last interglacial soil complexe; it attests from the continentalisation and cooling down occuring before the development of the pieniglacial loessic sedimentation. It can be subdivided into two units : the lower one belongs to the southern fringe of the boreal zonee and still correlated with the isotopic stage 5, and the upper one, corresponds to subarctic or arctic environment, correlated with stage 4. This complexe is not perfectly synchron : in some sites, the lower or the upper unit are lonly preserved. Thanks to micromorphology, several» organic faciès can be defined from their ecology on different substrata and throughout Europe.

Molluscs in loess, their paleoecological significance and role in geochronology — Principles and methods

The malacofauna of genuine wind-blown loess consists of a minor number of tolerant species occurring mostly in high amounts and reflecting open habitats with poorly developed calcareous soils. It shows a rather uniform character in space and time distinctly differing from all present-day assemblages of the temperate zone, and thus indicating a very peculiar environment characteristic of the loess steppe. In protected areas, particularly on valley slopes, the loess covers alternate with intercalations of slope sediments and soils including several other types of snail assemblages reflecting environmental changes in the course of the Quaternary climatic cycle. Among these malacocoenoses the interglacial faunas are of prime biostratigraphic importance. They are associated with strongly weathered forest soils and indicate woodland environments under very damp and warm climatic conditions. Transitional steppe and taiga assemblages occur in buried chernozem soils and in various slope sediments, e.g. in the pellet sands, overlying the interglacial soils and corresponding to early glacial periods. Although the fauna of proper loess shows a monotonous composition, it is possible to distinguish several types of loess assemblages corresponding to minor facies changes of loess environments in time and space; these are, for example, the Pupilla, Helicopsis striata and Columella faunas of Central Europe. A peculiar marshland fauna characterizes the so-called swamp-loess deposited in ephemeral swamps. In the marginal zones of the loess belt there occur also faunas partly differing from those of typical loess; this is true particularly of the Mediterranean region. The most important contribution provided by molluscan faunas from the loess series is the evidence of the maximum number of climatic cycles during the Quaternary period.

Thermoluminescence dating applied to paleosols

Thermoluminescence (TL) dating of Quaternary sediments has developed rapidly in the last few years. As paleosols often prove to be useful stratigraphic marker horizons, it is of great interest to obtain absolute ages for them. A technique is proposed which increases the range of TL dating of loess to some 300 ka. Special problems associated with paleosol TL dating, such as sampling and dose rate evaluation, are discussed. Three examples for paleosols from West German loess regions are presented: the intra-Würmian ‘Lohner Boden’ soil (28–30 ka), Lower Würmian chernozem-like soils (ca. 70 ka), and the penultimate interglacial soil (‘Kärlich Interglacial’, between 230 and 170 ka).

Pleistocene Climatic Changes and Landscape Evolution in the Kashmir Basin, India: Paleopedologic and Chronostratigraphic Studies

AbstractThe Kashmir Basin is filled with Pliocene-Pleistocene fluvio-lacustrine sediments. On the flank of the Pir Panjal these sediments, called “Lower Karewas”, are covered with loess deposits up to 25 m thick that contain numerous middle and late Pleistocene paleosols, mostly polygenetic pedocomplexes, which were classified by micromorphological studies. Thermoluminescence dates provide a chronostratigraphy of the late Pleistocene loess-paleosol sequences. On the Himalayan flank, the “Upper Karewas” are covered only with late Pleistocene loess-paleosol sequences. Their base is the last interglacial soil, developed ca. 110,000 ± 10,000 yr B.P. This soil is genetically comparable to the modern soil and, therefore, is thought to have developed under a deciduous forest in a “xeric” soil moisture regime. The loesses of last glacial age on both flanks of the basin contain three humus-rich Ah, mostly Aht, horizons, indicating three warm and mostly humid climatic episodes between ca. 80,000 and 50,000 yr B.P. The middle Pleistocene loesses contain at least four Bwt, or thick Bt, horizons developed during four interglacial periods, having climates similar to the present. Large parts of the Karewa Lake must have lasted until the end of the penultimate glacial age.

Thermoluminescence dating and its implications for the chronostratigraphy of loess-paleosol sequences in the Kashmir Valley (India)

The Karewa deposits of the tectonic basin of Kashmir in India are overlain by eolian loess. This loess (up to 25 m thick) is divided by several paleosols, which have been recently studied and classified in detail. Thermoluminescence dating of these deposits in conjunction with micromorphological analysis enables the following conclusions: 1. (1) The Bt soil horizon at around 9.5-m depth at Karapur and its stratigraphic equivalents at other localities is the last interglacial soil that can be compared to stage 5e of the deep-sea oxygen-isotope chronology. 2. (2) There were at least three warm, soil-forming episodes during the period 80–50 ka ago. 3. (3) The entire loess sequence at Kashmir spans at least 300 ka. 4. (4) The remanents of the Karewa lake touched the fringes of Himalayan flank at Burzahom until the end of the previous last glacial. 5. (5) Most of the radiocarbon dates reported so far are grossly underestimated.

The ‚loess’︁ section at Borden, Kent, SE England

AbstractA 5.3m profile originally described as loess with a buried interglacial soil is reinterpreted from petrographic evidence and thermoluminescence dating as a Holocene colluvial accretionary soil. Mineralogical analyses of coarse silt (16–63 μm) fractions suggest that most of the silty colluvium was derived from weathered Thanet Beds upslope, though some loess was incorporated during the final depositional phase. Thin sections show that clay illuviation occurred penecontem‐poraneously with deposition of colluvium. Thermoluminescence properties suggest partial optical bleaching of the grains during rapid deposition, which is consistent with a Holocene colluvial origin.

Scandinavian glaciations in the Bohemian Massif and Carpathian Foredeep and their relationship to the extraglacial areas

THE BOHEMIAN MASSIF The North European glaciations reached the northernmost part of the Bohemian Massif during the Elster and Saale (sensu lato) glacial stages. As for the Carpathian Foredeep, between the Bohemian Massif and Carpathian system, the ice advanced to the main European watershed between the Baltic and Black Seas. Glaciated and extraglacial are as are linked by the terrace systems of the rivers Labe (Elbe) , Ploucnice , Nisa and by the rivers of Northern Morava (Macoun et al., 1965; Sibrava, 1967). In the Carpathian Foredeep, south of the ice margin. terraces of the Morava and its tributaries represent the main link with the Danube terrace system which is in turn connected, through its tributaries , to the Alpine glaciations . The Carpathian Foredeep together with the Rhine valley is an important area for correlation of Quaternary stratigraphy between north European glaciated ar eas (and extraglacial zones) and the Alps. During the Elster and Saale glacial stages, Scandinavian ice advanced to the main European watershed near Hranice (49°30'). Quaternary sediments in the glaciated are a are represented by glaciofluvial, glaciolacustrine and glacigenic deposits from both glaciations. fluvial and proluvial deposits and by mostly decalcified eolian The Elster glaciations advanced into Czechoslovak sediments with buried fossil soils. territory in the northern part of the Bohemian Massif. South of the ice margin, fluvial deposits and exThe following Saale glaciation advanced to a lesser tensive loess covered eolian deposits are subdivided by ext ent and left its deposits north of the marginal well developed soil complexes; relatively dry paleomountain ranges of the Bohemian Massif in the climatic conditions are reflected in the typology of fossil G.D .R. and Poland. In the Elbe valley, between soils . Those of interglacial age are represented by Dresden and Pima, sediments of this glaciation overlie typical parabrownearth . Also of stratigraphic importthe fluvial gravels of a middle terrace , attributed to the ance are organic horizons and travertines which are rich Drenthe glacial stage (Sibrava, 1972) . in paleontological evidence. The Elster glacial in Bohemia is represented by two The basic stratigraphic system for the glaciated area advances , assigned to the Early (E1) and Late Elster was established by Macoun et al. (1965) . The deposits (E2) . No interglacial deposits or fossil soils are known of Scandinavian ice are represented by tills and by between both ice advances ; but both the petrographic glaciofluvial and glaciolacustrine deposits from the composition as well as lithology of the glacial deposits Elster and Saale glaciations. Zebera (1958) considered differ substantially (Sibrava , 1967). The Elster 2 glacial most of the deposits in front of the ice-lobe to be deposits grade into the upper layer of the 'Bohatice glaciolacustrine and believed in the existence of a large terrace' of the River Ploucnice . This terrace , consists of ice-dammed lake which reached up to the main two limits, the upper containing a mixture of nordic European watershed. pebbles which represents a link between the glaciated Macoun (1981) described three tills of Elster age and and non-glaciated areas. Near Usti, it enters the terrace three belonging to the Saale (Drenthe stage) glaciation . system of the Labe (Elbe) river which is thus linked to A parautochtonous fossil soil (gleyed brownearth) the Elster and Saale glaciations. The Usti terrace lies developed on the surface of the lowermost till shows a stratigraphically between two glaciations prior to the warm interglacial between the Elster tHis. The three Drenthe glacial stage, and is covered by loessic deposits Saale tills were probably laid down during repeated with three interglacial soil complexes (Buckova et al., advances or oscillations of the ice; intervening warmer 1967) : it is ascribed to the cold period within the periods were not more than interstadial in character Elster-Saale interglacial (Fuhne glacial stage according and represent only minor retreats of the ice .

TL dating of loess and fossil soils from the last interglacial-glacial cycle

TL dates on fine grains from loess and fossil soils have been obtained using the near ultraviolet emission of feldspars. The results are compared with data obtained previously with a blue filter, which enhances the emission of quartz. The values of equivalent doses calculated around 300°C using the “regen” method are in good agreement for both filters. For samples less than 50 ka the plateau test is particularly well fulfilled when using the near ultraviolet emission. Further down the section good plateaux were not obtained and the absolute meaning of older TL ages is still under question. In spite of this, the apparent TL ages provide enough evidence to solve particular chronostratigraphic problems, for example, enabling us to distinguish two periods of interglacial soil formation, which have been miscorrelated up to now.

Mineralverwitterung, tonmineralbildung und rubefizierung in Terrae calcis der slowakei Ein beitrag zum paläoklimatischen aussagewert von kalkstein-Rotlehmen in Mitteleuropa

Mineralverwitterung, tonmineralbildung und rubefizierung in Terrae calcis der slowakei Ein beitrag zum paläoklimatischen aussagewert von kalkstein-Rotlehmen in Mitteleuropa

Stratigraphie du Pléistocène récent et moustérien de tradition acheuléenne à Marcoing (Cambrésis - Nord de la France)

The Brickyard of Marcoing shows a lithostratigraphy of Late Pleistocene which is characteristic of the loess Region of North of France with the eemian interglacial soil, the weichselian loess and two frost-wedge rows. A greyish loam (« limon gris de Ladrière ») has given a Mouterian of Acheulean tradition including many Levallois flakes which are not retouched. This industry contains numerous triangular and cordiform handaxes, varied side-scappers and backed knives. The Mousterian of Acheulean tradition of Marcoing offers affinities with the industries of the Seine basin and of the Somme basin.

Evidence of Multiple Stades in the Lower Pleistocene of Northeastern Kansas

Nebraskan and Kansan glacial and glacio-fluvial deposits in Kansas occur only in the northeastern part of Kansas. generalized four-fold history of continental glaciation has long been accepted in the United States. Generally the highest till was correlated with the youngest glaciation and an underlying till correlated with the next youngest glaciation. In areas where only early Pleistocene glaciations occurred, this same method of correlation was practiced. Recognition of a more complex system of advances and retreats of ice in the Wisconsinan Stage lead to the adoption of substage or stade division of this stage. Each of the glacial stages is separated from the succeeding glacial stage by an interglacial stage. This period was one of relative stability under comparatively warm conditions during which extensive interglacial soils were developed in the periglacial regions as well as in the glaciated regions. Buried profiles of weathering, or fossil soils, are perhaps the most usable criteria for stratigraphic correlation and classification of the Pleistocene sediments in Kansas. The top of a buried soil is unmistakably an unconformity, and where deep well-developed soil profiles occur, a significant interval of nondeposition and only slight erosion is indicated. Interpretation of the soils within the Pleistocene sequence involves the evaluation of the soil horizons as interglacial or interstadial and may lead to errors in correlation. The strength of soil development is believed to be the most important factor in this interpretation. Pronounced zones of clay enrichment in the B horizon, considerable depth of leaching, great depth of oxidation, and significant thicknesses of secondary lime accumulation are believed to be more important and better indicators of interglacial nature of soils than the thickness of the humic A horizon which often has been removed by erosion or scour. Frye and Leonard (1949, 1952) described the exposure of two tills in a quarry in the Missouri River Bluff near Iowa Point in northeastern Doniphan County. well-developed soil on the lower till was indicative of a long period of weathering prior to deposition of the upper till.

Polygenese der fossilen lössböden der tschechoslowakei im lichte mikromorphologischer untersuchungen

All fossil soils of the loess series in Czechoslovakia are of polygenetic character which is most distinct in the interglacial soils and reflects the environmental changes due to the climatic cycle. For the most part the following stages of development of the Pleistocene soils can be distinguished: 1.(1) Weathering of loess — decalcification (initial stages of pararendsinas; later, development to braunerde type soil).2.(2) Segregation of the braunlehmplasma (parabraunerde type soil under broad-leaved forests in the warm humid climate of the maximum interglacial).3.(3) Granulation and floculation (“Vererdung”) of the braunlehmplasma (the climate becomes drier and colder).4.(4) Slight pseudogleyization of varying intensity (the climate becomes final interglacial).5.(5) New sedimentation and formation of humic soils of the chernozem type (the climate cecomes continental at the beginning of the new glacial phase).6.(6) Slight pseudogleyization due to a short humid oscillation.7.(7) Mechanical disturbances of the soil horizons by frost action and enrichment of CaCO3 due to the loessification (glacial climate).The Early Pleistocene soils (the pedocomplexes PK VI–VIII) differ wrom the younger ones (PK I–V) by the considerably higher degree of weathering. The phases of minimum sedimentation are represented in these soils by a braunlehm stage, shorter periods of temporary sedimentation are characterized by structural changes and enrichment by a weakly weathered allochthonous component.The paleosoils of the Middle and Late Pleistocene correspond to the arctic (weakly developed soils), baltic (different varieties of parabraunerde type soil) and pannonian (chernozemic soils) soil province in the conception of Kubiena (1956). The Early Pleistocene soils show a development tendency which characterizes the submediterranean and in several cases the subtropical soil province (Kubiena, 1964).

Ergebnisse neuerer Untersuchungen zur Würmlöß-Gliederung in Hessen

Abstract. The eolian sediments of the "Würm" following above the last interglacial soil Parabraunerde and pseudogleyed Parabraunerde respectively) can be divided — by characteristic soil horizons — into three sections (old, middle and young Würm). Typical for the old Würm are humic zones, for the middle Würm — besides several "Naßböden" browncoloured (weathered) zones of decalcification with a thickness of up to 1,1 m, and for the young Würm several weakly developed thin browneoloured weathering zones and "Naßböden" (wet soils). The most significant key horizon of the young Würm is the Kärlich tuff layer which recently was also encountered in Northern Hessen. Finally, the division scheme estabilished in Hessen is compared with the Würm-loess divisions in other countries of Europe.