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Figure 45. X-radiographs of coral core slabs show annual growth bands in Montastrea annularis from Hen and Chickens patch reef. (A) Note abnormally wide stress band deposited by the coral in response to an unknown cause during the winter of 1941-42. (B) Correlation of banding in seven different M. annularis. The four at left are from heads killed by cold-water temperatures in the winter of 1969-70. The three at right are from corals that were alive and healthy when sampled in September 1974. The topmost stress bands joined by a dark line correlate with demise of the corals in the left x-radiographs. The stress band for 1941-42 indicates that conditions must have been as severe as in 1969-70 although the corals survived the earlier stress. Other minor stress bands are very faint or do not correlate from coral to coral. Normal annual bands are correlative from coral to coral (modified from Hudson et al., 1976).

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Coastal & Marine Geology Program > Center for Coastal & Watershed Studies > Professional Paper 1751