The use of static global positioning system (GPS) equipment for accurate horizontal & vertical positioning in field geology operations at high latitudes is made difficult by the need to set up & operate a GPS reference station and limitations on the distance between the reference station & field GPS due to errors introduced by the ionosphere. Dual-frequency GPS receivers have the potential to eliminate these problems since they can eliminate ionospheric errors and thereby increase baseline lengths, thus potentially permitting the use of existing GPS reference stations. This paper describes the use of a dual-frequency receiver for establishing benchmarks along the Yukon River as a field trial of this technology. Field methods and post-processing of the data using GPS data from permanent receiving stations are described, and baseline results are presented. The derived benchmarks will be applied to a survey of fill thickness below the Yukon River.

A well-exposed section about 250 metres wide below the high water line of the Jennings River, Teslin Lake map area in northern British Columbia shows part of the Teslin Fault and provides an opportunity to constrain the fault's kinematic history by direct ground observations. This report describes preliminary structural observations of this section of the Teslin Fault, including the rock types involved, mylonitic & ultramylonitic structures, and deformation. Indications of two main episodes of shearing are discussed.

This paper presents a determination of the evolution characteristics of a set of shale pore-structure components (storage porosity, connecting porosity, flow path size, and flow path density) with compaction. The pore-structure component data are derived from bulk petrophysical data (permeability, porosity, and formation factor as a function of increased pressure) reported for seven shale & mudstone samples. Basic pore-structure models and theory are also presented.

The final year of the Nechako NATMAP project to study the geology of central British Columbia was used to research information collected in the field & laboratory, and to compile & document the study results. This article includes a review of upcoming publications & other products, by type of product: maps, journal articles, conference presentations, and computer products, as well as ongoing research on petrology, palaeontology, terrane characterization, tectonics & structure, and Quaternary geology.

This paper reports the results of remapping the Mountain Grove pluton, situated in the Sharbot Lake domain in the central part of the Central Metasedimentary Belt, Grenville Province, Ontario. The pluton, previously mapped as a single body of gabbroic rock, is now described as comprising two distinct intrusions. The paper begins with an overview of its geologic setting, then describes the lithology of the two intrusion units, associated dykes, and neighbouring intrusions & plutons. The geochronology of the pluton and its mineral deposits are also briefly noted.

This study presents theoretical aspects and results of analyzes of the adsorbed water thicknesses and number of water molecular layers on pore surfaces for 11 sedimentary rock samples obtained from 850-950 metres depth in a Northwest Territories well. An additional purpose of the study was to determine if the adsorbed water content shows an increase with decreased temperature below 25 degrees C. Information is included on the analytical methodology. The results provide information that can be used to model the effect of temperature on the permeability history of compacting shale & mudstone under low temperature environments.