Reconnaissance with a sub-bottom profiler has revealed the structural plan of the largely submarine Acadian Triassic Basin in the Bay of Fundy. The Bay is floored mainly by Triassic clastic rocks which have been warped into a broad syncline. The basalt of the North Mountain-Cape Split-Cape Blomidon cuesta may be traced underwater as far as Quaco Ledge, defining the northeastern limb of the Fundy syncline. The basin's northwestern margin is a zone of normal faults, from 2 to 10 km seaward from the shore. While the basin is, therefore, technically a half-graben, the central syncline is the dominant structure.