0000000000634125
AUTHOR
Tobias Kluge
Reconstruction of drip-water δ<sup>18</sup>O based on calcite oxygen and clumped isotopes of speleothems from Bunker Cave (Germany)
Abstract. The geochemical signature of many speleothems used for reconstruction of past continental climates is affected by kinetic isotope fractionation. This limits quantitative paleoclimate reconstruction and, in cases where the kinetic fractionation varies with time, also affects relative paleoclimate interpretations. In carbonate archive research, clumped isotope thermometry is typically used as proxy for absolute temperatures. In the case of speleothems, however, clumped isotopes provide a sensitive indicator for disequilibrium effects. The extent of kinetic fractionation co-varies in Δ47 and δ18O so that it can be used to account for disequilibrium in δ18O and to extract the past dri…
Hydrogeochemistry and fractionation pathways of Mg isotopes in a continental weathering system: Lessons from field experiments
Abstract The potential of magnesium isotope records from cave carbonate archives (speleothems) has been documented but remains underexplored. This is due to the limited knowledge regarding the complex suite of physico-chemical and biological disequilibrium fractionation processes affecting meteoric fluids in the soil zone, the carbonate hostrock and calcite precipitation in the cave. This study presents δ 26 Mg data from a monitored cave in Germany (Bunker Cave) including rain water (δ 26 Mg: − 0.70 ± 0.14‰), soil water (δ 26 Mg: − 0.51 ± 0.10‰) and drip waters (δ 26 Mg: − 1.65 ± 0.08‰) sampled between November 2009 and May 2011. Field precipitation experiments, i.e., calcite precipitat…
A 4000-year long Late Holocene climate record from Hermes Cave (Peloponnese, Greece)
The societal and cultural development during the Bronze Age and the subsequent Iron Age was enormous in Greece, however interrupted by two significant transformations around 4200 years b2k (Early Helladic II/III; b2k refers to years before 2000 CE) and 3200 years b2k (end of Late Helladic III). Artefacts and building remains provide some insights into the cultural evolution, but only little is known about environmental and climatic changes on a detailed temporal and spatial scale. Here we present a 4000-year long stalagmite record (GH17-05) from Hermes Cave, Greece, located on Mount Ziria in the close vicinity of the Late Bronze Age citadel of Mycenae and the Classical-Hellenistic polis of …
Last glacial millennial-scale hydro-climate and temperature changes in Puerto Rico constrained by speleothem fluid inclusion δ<sup>18</sup>O and δ<sup>2</sup>H values
Abstract. We present speleothem fluid inclusion δ18Of and δ2Hf values from Larga Cave, Puerto Rico, that covers the interval between 46.2 to 15.3 ka before present on millennial scale, including the Last Glacial Maximum (LGM) and several stadial and interstadial cycles. The dataset can be divided in two main clusters of stable isotope compositions of the fluid inclusion water with respect to the global meteoric water line which coincide with strong variations in the water content of the stalagmite. In particular, this clustering is found to be climate related, where the first cluster comprises samples from cold and dry periods, such as Heinrich and Greenland stadials, as well as parts of th…
Evaluating the potential of tree-ring methodology for cross-dating of three annually laminated stalagmites from Zoolithencave (SE Germany)
Abstract Three small stalagmites from Zoolithencave (southern Germany) show visible laminae, which consist of a clear and a brownish, pigmented layer pair. This potentially provides the opportunity to construct precise chronologies by counting annual laminae. The growth period of the three stalagmites was constrained by the 14C bomb peak in the youngest part of all three stalagmites and 14C-dating of a piece of charcoal in the consolidated base part of stalagmite Zoo-rez-2. These data suggest an age of AD 1970 for the top laminae and a lower age limit of AD 1973–1682 or AD 1735–1778. Laminae were counted and their thickness determined on scanned thin sections of all stalagmites. On stalagmi…