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See detailA 500-year seasonally resolved δ 18 O and δ 13 C, layer thickness and calcite aspect record from a speleothem deposited in the Han-sur-Lesse cave, Belgium
Van Rampelbergh, M.; Verheyden, S.; Allan, Mohammed ULg et al

in Climate of the Past (2015), 11

Speleothem δ18O and δ13C signals enable climate reconstructions at high resolution. However, scarce decadal and seasonally resolved speleothem records are often diffi- cult to interpret in terms of climate ... [more ▼]

Speleothem δ18O and δ13C signals enable climate reconstructions at high resolution. However, scarce decadal and seasonally resolved speleothem records are often diffi- cult to interpret in terms of climate due to the multitude of factors that affect the proxy signals. In this paper, a fast- growing (up to 2 mm yr−1) seasonally laminated speleothem from the Han-sur-Lesse cave (Belgium) is analyzed for its δ18O and δ13C values, layer thickness and changes in cal- cite aspect. The studied record covers the period between AD 2001 and 1479 as indicated by layer counting and con- firmed by 20 U / Th ages. The Proserpine proxies are sea- sonally biased and document drier (and colder) winters on multidecadal scales. Higher δ13C signals reflect increased prior calcite precipitation (PCP) and lower soil activity dur- ing drier (and colder) winters. Thinner layers and darker calcite relate to slower growth and exist during drier (and colder) winter periods. Exceptionally dry (and cold) winter periods occur from 1565 to 1610, at 1730, from 1770 to 1800, from 1810 to 1860, and from 1880 to 1895 and correspond to exceptionally cold periods in historical and instrumental records as well as European winter temperature reconstruc- tions. More relative climate variations, during which the four measured proxies vary independently and display lower am- plitude variations, occur between 1479 and 1565, between 1610 and 1730, and between 1730 and 1770. The winters during the first and last periods are interpreted as relatively wetter (and warmer) and correspond to warmer periods in historical data and in winter temperature reconstructions in Europe. The winters in the period between 1610 and 1730 are interpreted as relatively drier (and cooler) and correspond to generally colder conditions in Europe. Interpretation of the seasonal variations in δ18O and δ13C signals differs from that on a decadal and multidecadal scale. Seasonal δ18O variations reflect cave air temperature variations and suggest a 2.5◦C seasonality in cave air temperature during the two relatively wetter (and warmer) winter periods (1479–1565 and 1730–1770), which corresponds to the cave air temper- ature seasonality observed today. Between 1610 and 1730, the δ18O values suggest a 1.5◦C seasonality in cave air tem- perature, indicating colder summer temperatures during this drier (and cooler) interval. The δ13C seasonality is driven by PCP and suggests generally lower PCP seasonal effects be- tween 1479 and 1810 compared to today. A short interval of increased PCP seasonality occurs between 1600 and 1660, and reflects increased PCP in summer due to decreased win- ter recharge. [less ▲]

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See detailSeasonal variations recorded in cave monitoring results and a 10 year monthly resolved speleothem δ18O and δ13C record from the Han-sur-Lesse cave, Belgium
Van Rampelbergh, M; Verheyden, S; Allan, Mohammed ULg et al

in Climate of the Past Discussions (2014), 10

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See detailCarbon-isotope analysis of fossil wood and dispersed organic matter from the terrestrial Wealden facies of Hautrage (Mons Basin, Belgium).
Yans, Johan; Gerards, Thomas ULg; Gerrienne, Philippe ULg et al

in Palaeogeography, Palaeoclimatology, Palaeoecology (2010), 291

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See detailEchinoderm skeletons record sea temperatures
Ranner, Herwig; Ladrière, Ophélie ULg; Navez, Jacques et al

Poster (2006)

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See detailEchinoderm skeletons record sea temperatures
Ranner, Herwig; Ladrière, Ophélie ULg; Navez, Jacques et al

Poster (2005, December 31)

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See detailEffects of temperature on the chemistry of the echinoderm skeleton
Ranner, Herwig; Ladrière, Ophélie ULg; Navez, Jacques et al

Poster (2004)

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See detailEnvironmental effects on the chemistry of the echinoderm skeleton
Ranner, Herwig; de Jonghe, Caroline; Ladrière, Ophélie ULg et al

Poster (2004)

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See detailFaunal/floral and isotopic responses to Milankovitch precession cycles and environmental changes in the upper Gulpen Formation (Upper Maastrichtian) at the CBR-Lixhe and ENCI-Maastricht bv quarries
Felder, P. J.; Keppens, E.; De Clercq, Bernadette ULg et al

in Netherlands Journal of Geosciences-Geologie en Mijnbouw (2003), 82(3), 275-281

Two sections, just below the Nivelle Horizon in the upper Gulpen Formation (Upper Maastrichtian), and seven kilometres apart (CBR-Lixhe and ENCI-Maastricht bv quarries) have been analysed (samples every 5 ... [more ▼]

Two sections, just below the Nivelle Horizon in the upper Gulpen Formation (Upper Maastrichtian), and seven kilometres apart (CBR-Lixhe and ENCI-Maastricht bv quarries) have been analysed (samples every 5 cm) for dinocyst, pollen grains and bioclast contents as well as for carbon and oxygen isotopic composition, to obtain better insight into the influence of weathering on these sediments. The CBR section lies above groundwater level, while that at the ENCI quarry is some metres below. At the former quarry we recognised the influences of weathering (karst) nearby. At ENCI, palynological, bioclast and stable isotope results of the carbonate phase (mainly consisting of coccoliths) co-vary remarkably, displaying two cycles which may be interpreted tentatively as climatic fluctuations. The partial derivative(18)O curve varies roughly between -1.6parts per thousand and -1.1parts per thousand (on PDB scale), corresponding to a temperature change of about 2degreesC. Less negative values (i.e. cooler seawater) coincide with larger amounts of pollen of Normapolles and Triporates type assumed to represent temperate forest elements of a vegetation also containing tropical elements such as palms. Assuming the 5 cm sample intervals at ENCI to correspond to 1 ka, climatic maxima (and minima) may be 20-25 ka apart, obviously recalling Milankovitch precession cycles. These are independent of a sharp sedimentological change noted in the upper part of the lowest cycle (samples 42 to 24). Upwards of sample 42, bioclast contents increase and dinocysts, Spiniferites in particular, decrease significantly, corresponding to a marked shallowing. This turning point is also recorded in the partial derivative(13)C curve at ENCI. Bioclast percentages appear to follow composite trends that are influenced by both climatic and sedimentological conditions. [less ▲]

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See detailDiagenèse des monticules micritiques de la partie supérieure du Frasnien du Synclinorium de Dinant (Belgique, France)
Boulvain, Frédéric ULg; Herbosch, A.; Keppens, E.

in Comptes Rendus de l'Académie des Sciences. Série II, Mécanique, Physique, Chimie, Sciences de l'Univers, Sciences de la Terre (1992), 315

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