The inner Northeast Newfoundland Shelf and coast were mapped to determine the potential of the region to host marine placer minerals, particularly gold. Five units were mapped: unit 1, bedrock; unit 2, glacial diamicton; unit 3, glaciomarine mud; unit 4, postglacial mud; and unit 5, postglacial sand and gravel. These units occur in five zones defined by depth, as follows: 1) deep, offshore basins contain thick deposits of glaciomarine, gravelly, sandy mud overlain by postglacial mud; 2) in shallower water, these units have been winnowed by currents; 3) above a depth of about 200 m, the seabed has been furrowed and pitted by grounded icebergs; 4) above a depth of 70 m the seabed is highly mobile; 5) the intertidal/supratidal zone is narrow and rocky, except along The Straight Shore. Relative sea level has been falling throughout postglacial time in the west, but in the east it dropped to -20 m about 8.7 ka before rising again. Fiords contain thick deposits of glaciomarine mud, capped by thin, postglacial mud. Shallow, outer-fiord areas are heavily imprinted by iceberg furrows and pits. In zone 4, which has the highest potential to host marine placers, extensive gravel and sand deposits occur on the wide, shallow, inner shelf between Cape Freels and Hamilton Sound, but no gold has been found in samples, likely because of a lack of gold mineralization onshore. Some gold was found at Deer Cove in Baie Verte, although the volume is small and the grades low.

Hamilton Sound is a shallow, wave-exposed cmbaymcnt on the northeast coast of Newfoundland. Four scismostratigraphic units are recognised: (1) bedrock (acoustic basement); (2) a unit with incoherent reflections, interpreted as Late Wisconsinan glacial diamicton or till, which in places forms small drumlins; (3) a thin, acoustically stratified, draped unit found in the deepest parts of the eastern sound, interpreted as glacimarinc gravelly mud; and (4) an uppermost unit with an acoustically stratified, ponded facies, and a facies which can be acoustically incoherent. Unit 4 consists of sandy mud, muddy sand, sand and gravel, and results from reworking of units 2 and 3. Three types of seabed occur: (1) bedrock; (2) bouldery gravel or gravel, sub-angular to rounded, which overlies, and is derived from, glacial diamicton of acoustic unit 2. The coralline alga Lithothamnion sp. coats some clasts on their upper surfaces and some clasts completely. This, together with the occurrence of gravel ripples in several areas, is evidence of intermittent sediment mobility; and (3) gravelly sand, sand, muddy sand, or sandy mud, located in basins. Seabed features in this zone include dunes, iceberg furrows and pits. The regional relative scalevel curve is constrained by two types of morphological evidence: rounded drumlin crests at depths below 19 m which would have been truncated if sea level had fallen below -18.5 m, and (wave-cut) terraces at depths of 17 to 21 m. These data are indicative of a -17 m lowstand of relative sea level. Radiocarbon dates from a vibracore suggest that the lowstand occurred prior to 8.6 ka B .P. During the lowstand Fogo Island was connected to the mainland by a narrow isthmus.Le detroit d'Hamilton est une baie peu profonde et exposee aux vagues sur la cote nord de Terre-Neuve. Quatre unites sismostratigraphiqucs sont distinguees : (1) la rochc de fond (le soclc acoustique); (2) une unite montrant des reflections desordonnees, interpretee comme etant un diamicton glaciaire ou un till du Wisconsinien tardif et qui forme localement de petits drumlins; (3) unc unite mince ct etcnduc, montrant une stratification acoustiquc ct qui se rctrouvc dans les parties les plus profondcs du segment est du detroit; cette uni~ est interpretee comme etant une boue graveleuse glaciomarine; et (4) une unite sommitale comprenant un facies d'etendue rcstreinte, stratifie acoustiquement, et un facies qui peut montrer un desordre acoustique. L' unite 4 consiste en boue sableusc, sable boucux, sable ct gravier et provient du remaniement des unites 2 et 3. Il ya trois types de fond marin : (1) la roche de fond; (2) du gravier a blocs OU du gravier, subanguleux a arrondi, qui recouvre et est derive du diamicton glaciaire de l'unitC acoustiquc 2 . L'algue corallienne Lithothamnion sp. recouvre certains clastcs sur lcur partie supericure ou d'autres completement. Cet element, combine a la presence d' ondulations dans le gravier a plusieurs endroits, est unc indication d' une mobilite intermittente du sediment; (3) du sable gravel...

The Fraser River delta is underlain by thick Quaternary sediments and Tertiary sedimentary rocks separated by an unconformity with up to 800 m of relief. Pleistocene sediments consist mainly of sand and silt deposited in proglacial glaciomarine environments during several glaciations. These glacial sediments are separated by nonglacial marine deposits or, more commonly, by unconformities. The Pleistocene sequence is overlain by sediments of the Holocene Fraser River delta across a surface with up to 300 m of relief. The delta deposits comprise bottomset, foreset, and topset units. The bottomset unit consists mainly of clayey silt. Silty and sandy foreset deposits overlie the bottomset unit, and are unconformably overlain by 10 to 30 m of distributary- channel sands. The channel sands, which constitute the lower part of the topset unit, grade upward into several metres of intertidal and floodplain silts, and peat. The delta started to form about 10 000 years ago, when the Fraser River advanced its floodplain beyond the Pleistocene uplands at New Westminster. About 6000 years ago, the locus of deposition shifted from southward into Boundary Bay to westward into the Strait of Georgia proper.

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