Mesozoic-Cenozoic Deposition Along Atlantic Continental Shelf >From Scotian Shelf, Canada, To Baltimore Canyon Trough, United States: ABSTRACT

Abstract

In 1982, geologic data from 17 wells in the Baltimore Canyon Trough were released to the public. These wells provide sufficient data for definition of regional stratigraphic units in the Baltimore Canyon Trough. Prior to 1982, the only publicly available data from deep wells on the northern United States outer continental shelf were from two COST wells in the George Bank basin and two COST and three exploratory wells in the Baltimore Canyon Trough. Lithologic similarities between the Scotian Shelf formations and the rock units penetrated by these COST wells have been observed in the past. In this study, the stratigraphic terminology developed for the Scotian Shelf is extended through the Georges Bank basin and is informally applied to the Baltimore Canyon Trough strata as homotaxial equivalents. The Late Triassic(?) to Jurassic salt, carbonate, clastic, and carbonate sequence penetrated in the Georges Bank basin is correlative with the Argo, Iroquois, Mohican, and Abenaki Formations on the Scotian Shelf. Exploratory wells in the Baltimore Canyon Trough were not deep enough to penetrate equivalent rocks. However, previous seismic studies of the trough suggest that a carbonate complex equivalent to the Abenaki Formation may exist beneath the present-day slope. Upper Jurassic to Lower Cretaceous strata in the Georges Bank basin and Baltimore Canyon Trough are equivalent to the Scotian Shelf deltaic sandstones and shales of the Mohawk, Mic Mac, Missisauga, Naskapi, and Logan Canyon Formations. These deltaic deposits are overlain by upper Lower Cretaceous to Upper Cretaceous marin mudstones and shales that are equivalent to the Scotian Shelf Dawson Canyon Formation. The Cenozoic strata in the Georges Bank basin and Baltimore Canyon Trough consist of shale, mudstone, chalk, and unconsolidated sand. On the Scotian Shelf, the Cenozoic section is generally sandier and consists of the Banquereau Formation, an interbedded mudstone and sandstone sequence, and the Laurentian Formation, which consists of glacial and proglacial sediments. End_of_Article - Last_Page 502------------