Volume 13, numéro 3, december 1977

EN :

Examination of the structural and stratigraphic sequences in southern New Brunswick indicates that the area evolved under the influence of a series of major faults. Relatively localized faulting persisted for at least 450 to S00 Ma.

In Part 1 the effects of the faults are systematically outlined over five time intervals beginning in the late Precambrian (Hadrynian), continuing through parts of the Ordovician, Silurian, Devonian and Carboniferous and ending in the Triassic. The relationships of various generations of faults to depositional environments in contemporaneous basins and the regional structural setting are documented.

In Part 2 evidence concerning the nature of the major faults and fault zones is presented. Properties peculiar to the southern New Brunswick structures are their repeated association with volcanic rocks, their distinction as narrow zones of stratigraphic and structural discontinuity and their persistant control on the manifestation of stresses associated with repetitive orogeny. Interpretions of the faults are proposed which identify them as long~lived, mechanically weak, dislocation zones in the lithosphere (i.e."deep-faults").

EN :

A system of photogeologic interpretation has been applied on a regional scale in the Caledonia area of New Brunswick, Canada, The orientation of about 700 photolineamente has been measured and their distribution analysed. A statistical partitioning technique applied to the whole region produced six major trends with the strongest trends occurring at O97±+7, l65±6± and l4l±9± . None of the strong trends coincides with the orientation of major faults in the area. Detailed examination of structural domains suggests the presence of more than six lineament trends. Correlation of trends from domain to domain is difficult and the genetic significance of lineaments in view of the scarcity of ground information, remains in doubt.

EN :

The Golden Grove gravity high in southern New Brunswick is associated with mafic intrusive rocks ranging from diorite to gabbro. The anomaly was interpreted with the aid of an iterative two-dimensional gravity modelling program used in conjunction with a non-linear optimization computer package MINUIT. For minimization, the simplex method of Nelder and Mead and the variable metric method of Fletcher were used with constraint. The optimum causative body parameters indicate that the mafic intrusive mass is a sill-like (tabular) body, having a depth extent of about 1 km, with outward dipping contacts.