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This review of annually laminated speleothems firstly considers the four types of annual laminae found within speleothems: fluorescent laminae formed by annual variations in organic matter flux; visible or petrographic laminae, formed by annual variations in calcite texture or fabric; calcite-aragonite couplets; and finally trace element laminae. The methods available to confirm the annual nature, or otherwise, of lamina deposition are reviewed. We consider the use of annual laminae in chronology building, with particular relevance to palaeoclimate reconstructions. Finally, the use of annual lamina width as a palaeoclimate proxy is reviewed.Keywords: speleothem, stalagmite, annual laminae, paleoclimate, geochronology removes the annual signal, nor so close to the surface that sub-annual events dominate over annual ones. Where all three of these cases are true, then annually laminated stalagmites should be expected to be found in the geological record, with an annual lamina width in the range of 10 to 1000 µm, depending on climatic and geological controls. The stronger the surface annual climate forcing, the more likely that annually laminated stalagmites will be formed over other deposition types. Likewise, in the majority of speleothems, all three requirements for annual lamina formation are not met, and therefore within an individual cave, speleothems can preserve a wide range of laminated and non-laminated forms.Historically speaking, after the first observations by Allison (1926), the next advance was the first radiometric demonstration of annual visible laminae in a speleothem from the USA in 1960 (Broecker et al., 1960, based on earlier observations of Orr (1952)). Subsequently, the concept of annual rhythms preserved in speleothems was again lost for around 30 years. Data presented by Shopov in the late 1980s suggested that speleothem fluorescence time series might demonstrate an annual periodicity, although no radiometric data was available to confirm this (Shopov et al., 1989). In 1992, Genty (1992) also demonstrated annual visible laminae in some European stalagmites, and Baker et al.(1993) confirmed annual fluorescent laminae in a Scottish stalagmite. Subsequent to these works, the possibility of visible and fluorescent annual lamina deposition Abstract:

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