Initial assessment and visual communication of the salient features of large sets of geochronological age data are commonly achieved with binned frequency histograms or probability density distributions. This paper describes the mathematical basis of traditional binned frequency histograms and probability density distributions, then compares & contrasts the advantages & limitations of both methods for displaying absolute age data. Important points related to the use of these diagrams as the principal means of communication of such data are noted.

Presents results of 1999 field studies focusing on the structure & stratigraphy within the Wallace Lake greenstone belt of east central Manitoba. The stratigraphic results involve redefinition of some of the sequences previously described in the belt and the introduction of new stratigraphic nomenclature. The nature of the contact between stratigraphic assemblages, and the internal stratigraphy of these assemblages, is then presented. This is followed by a discussion of the stratigraphic position of various komatiitic units found in the belt. The final sections describe the geochemistry of the volcanic rocks and the structural history of the greenstone belt.

The North Caribou terrane is one of the largest blocks with continental affinities in the western Superior Province. This paper reviews field relationships at the southern margin of this terrane in the western Uchi belt between Trout Lake, north-west Ontario, and Lake Winnipeg, Manitoba. After an introduction on the regional geological framework, the paper describes the Trout Lake Batholith, the Red Lake-Garner Lake lobe, the Bloodvein-Wanipigow River corridor, the English Lake magmatic complex, and the eastern Lake Winnipeg area. Implications of the observations for crustal architecture are discussed.

This study examines aspects of the geological evolution of the Sharbot Lake domain and compares it with that of neighbouring domains & terranes in the Central metasedimentary belt, Grenville Province, Ontario. The study reports uranium-lead zircon & titanite geochronological ages for a granodiorite phase of the Pakenham intrusion from the northern part of the Sharbot Lake domain. The new data expand the known range of magmatism in this part of the belt, elucidate the early tectonic evolution of the domain, and constrain the timing of overprinting metamorphism. Possible links between the Pakenham structure and the Wolf Grove structure to the south-east are also discussed.

This study used major & trace-element geochemistry to characterize the granitoid rocks of the Shikag-Garden lakes area of northern Ontario and to examine their petrogenesis & tectonic setting. Neodymium isotopes were examined to examine crustal recycling and to estimate the age of crustal sources contributing to the granitoid rocks. The data are subsequently interpreted to shed light on the distribution of basement terranes in the central Wabigoon Subprovince.