Figure 4. Alkenone records of concentration (µg/g dry sediment) and temperature estimated from the Prahl et al. (1988) relationship of unsaturation to growth temperature, compared to the oxygen isotopic record of G. ruber (Peterson et al., Chap. 4, this volume), on the Peterson et al. time scale. The arrows point to the location of the first laminated sediments in the Holocene from Hole 1002C, which corresponds to a spike of high alkenone concentration, high inferred paleoproductivity, and a short interval of cool surface waters. YD = the Younger Dryas Event, LGM = last glacial maximum.