LARGE SERPULID WORM TUBE AGGREGATES INDICATE AN ABRUPT MID-HOLOCENE TRANSITION FROM MARINE TO RESTRICTED HYPOSALINE CONDITIONS

Large aggregates of calcareous serpulid worm tubes recorded paleoclimate conditions as they colonized the mid to late Holocene Enriquillo embayment. Serpulid worms flourished in the Enriquillo embayment following the demise of the coral reef complex at 5 ka. While serpulid tubes are found in thin layers and as single tubes encrusting corals in normal marine deposits around the lake, they dominated the later environment in a unique aggregate form. Large monospecific mounds up to 2.8 m in height cap the reef sequence and mark the extent of different paleoshorelines around the periphery of the valley. These serpulid mounds are thought to represent the period of transition between open marine conditions and a hyposaline lagunal environment (Guerard et al, 2004).