Abstract
Studies of cores from three major estuaries in the middle Atlantic region (Hudson River, Delaware Bay, and Chesapeake Bay) reveal the following: (1) much of the upper Wisconsinan-Holocene estuarine facies consists of organic-rich fine-grained clasts; (2) major aggradation of this facies began about 11,000 radiocarbon years B.P. and possibly somewhat earlier; (3) chemical and semi-quantitative analyses of estuarine facies samples from the three areas show the facies are very similar, whereas a lacustrine fades in the Hudson estuary has a significantly different chemical composition than the estuarine facies; (4) the clay mineralogy in the estuarine facies in all three areas is similar (all clay-types are present--kaolinite, illite, montmorillonite, and chlorite); and (5) playnologic studies indicate that the forests bordering the estuaries were progressively more aboreal from south to north during the period of aggradation of the estuaries.