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A 2000‐year lipid biomarker record preserved in a stalagmite from north‐west ScotlandNARA Subscribed
Previous studies on lipid biomarkers preserved in Chinese stalagmites have indicated that ratios of low‐molecular‐weight (LMW) to high‐molecular‐weight (HMW) n ‐alkanes, n ‐alkan‐2‐ones, n ‐alkanols and n ‐alkanoic acids can be used as an index of vegetation versus microbial organic matter input to the system and, by extension, a marker of climatic changes, with increases in the proportion of LMW compounds coinciding with cold...
Late Quaternary speleothem pollen in the British IslesNARA Subscribed
As with many terrestrial areas, the British Quaternary sequence is characterised by incomplete, fragmentary records, whose correlation is based on stratigraphic or biostratigraphic techniques due to the lack of radiometric ages beyond the ∼40 kyr limit of 14 C dating. Speleothems (secondary cave calcite deposits) offer a significant advantage over many sources of palaeoenvironmental information; they can be dated to a high pre...
An annually laminated stalagmite from Southeastern Ethiopia grew for 443±8 yr starting at 5023 yr BP (±160 yr) as determined by lamina‐tuned U‐Th dating. The speleothem shows three growth phases: (1) an initial phase where the stalagmite has a candlestick shape, deposited by relatively slow rate drip water; (2) a middle growth phase where laminae grow on the flanks, suggesting faster drip rates; and (3) a final growth phase wh...
The magnitude of recent warming, and the variability of climate on centennial‐millennial time scales are compromised by questions concerning the ability of tree rings to capture low‐frequency climate fluctuations. Annually laminated stalagmite records can potentially provide a low‐frequency climate archive through variations in annual growth rate. Presented here is an initial attempt to demonstrate the applicability of annuall...
Stalagmite lamina doublets: a 1000 year proxy record of severe winters in northwest Scotland?NARA Subscribed
Stalagmites can contain annual luminescence laminae, and some samples provide long continuous chronologies from which climatic information can be extracted. One such site is Uamh an Tartair in Assynt, northwest Scotland, where most stalagmites contain continuous laminae sets for the last two to three millennia. At this site, the normal mode of deposition is for one luminescent lamina to be deposited in autumn, derived from lum...
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