The Mount Costigan Pb-Zn deposit is located about 40km east of Plaster Rock, New Brunswick within the Early Devonian Costigan Mountain Formation, in the Matapedia Cover Sequence (formerly the Cialeur Bay Synclinorium). It occurs about 250m east of the summit of Mount Costigan within a series of brecciated and unbrecciated crystal and lapilli tuff, rhyolite and minor siltstone which are exposed in six trenches (North, South, East, West, Southwest and Central). To the west the Costigan Mountain Formation is overlain by the Wapske Formation. The most significant feature of the deposit is the large amount of brecciation, which, in the Central Trench, also serves as the main sulphide host. Petrographic studies indicate that the breccia consists of angular to subangular blocks of massive and banded crystal tuff, massive to spherulitic to flow-banded rhyolite and minor lapilli tuff. The Mount Costigan deposit is interpreted to represent a base metal variety of epithermal deposit. (Abstract shortened by UMI.)

A model for Wisconsinan glaciation and deglaciation of Hudson Bay is proposed based on depositional facies of the surficial sediments. These facies, defined on the basis of texture, composition, and acoustic character, indicate that sediment distribution is controlled primarily by Late Wisconsin glaciation. Post-glacial sedimentation is restricted to the shallow marine environment (100m deep) and involves reworking of glacially-derived sediments by rivers and/or marine currents. Deposition due to sea-ice rafting is minor. Within the glacigenic sediments, dispersal trends of distinctive lithologies and mineralogies (derived from sources adjacent to and underlying the bay) indicate that (1) western Hudson Bay was glaciated by ice flow eastward from a centre in the District of Keewatin, and (2) the eastern and southern bay was glaciated by ice flow westward from a dispersal centre in Nouveau Quebec. Seafloor geomorphic features and sediment composition suggest that deglaciation was focused at the confluence between these two ice sheets, possibly through ice streaming and calving bay formation. Eastward and southward dispersal of sediment derived from sources within the bay suggest a residual ice mass remained centered over Hudson Bay following glacial maximum. The deglaciation model invokes stabilization of the ice margin in the north, extension of a calving bay in Hudson Strait into west-central Hudson Bay, northward drainage of proglacial lakes along major bathymetric depressions, and, finally, rapid collapse of the ice sheet.

The objectives of this thesis are to collect baseline data on meteorological and hydrological processes and the geometry and hydrogeological characteristics of the fracture network, in order to improve the knowledge for the development of a site-specific conceptual model of deep groundwater flow systems in British Columbia's mountainous terrain. To reach the objectives of this project, a monitoring network consisting of surface and underground equipment was installed in the Price Mine area, which is located on the Price Hillside of the east flank of Mount Myra, Vancouver Island. Rainfall, air temperature, atmospheric pressure, hydraulic heads in surface and underground drillholes and discharge from mine drifts were measured from August 1994 to June 1997. Also, as part of the project, a structural and hydrogeological mapping of major structural features within Mount Myra's underground workings was carried out to obtain an estimate of the hydrological importance of each geological structure in the Price Mine. The results have demonstrated the large impact of the rainy season on the hydrogeological system on the Price Hillside. Water levels in drillholes, along with discharge, increase drastically at the beginning of the first severe storms during the fall and maintain high levels until the end of the spring. The correlation and spectral analyses of the hydraulic data have shown the fast response of the hydraulic system following rainfall events and indicate that a substantial part of the Price Mine outflow is associated with water circulating in the fracture network intersected by the drillholes located in the fault area. The water levels in drillholes located in more-fractured rocks, near large faults, fluctuated more and showed a strong stormflow component as opposed to water in drillholes located in more-massive rock. In the fault areas in particular, the groundwater flow system adjusts to the rainy season by the upgradient displacement of the hinge point, which is the limit between recharge and discharge areas, in order to cope with this substantial increase in winter recharge. Since the change in groundwater flow appears to occur only in the most fractured areas this observation suggests that the fault zones act as the major flow channels that may control the entire groundwater flow on the Price Hillside. A conceptual model of the hydrogeological system of the Price Hillside was therefore developed on the basis of the observations made during the course of this project. (Abstract shortened by UMI.)

The Campbell mine is located in the eastern part of the Red Lake greenstone belt, Uchi Subprovince. Auriferous veins are parallel to S2, and are termed foliation parallel auriferous veins (NW striking, SW dipping). Auriferous veins also occur in shear zones which are oblique to the regional NW trending foliation (foliation-oblique deformation zones). These auriferous veins occur proximal to the F2 fold hinges. The deformation zones are typically meters to 10's of meters wide, and are characterized by more intense foliation development, and abundant carbonate veins and veinlets. Progressive D2 shortening resulted in a late D2 decollement along the southwestern limb of the Balmer synform, cutting and offsetting auriferous mineralization. Several stages of hydrothermal activity are recognized in the Campbell mine area. Subsequent Au mineralization occurs in quartz veins and quartz + arsenopyrite hydrothermal breccias within quartz + carbonate veins; thus most of the Au mineralization overprints pre-existing quartz + carbonates within the D2 shear zones. Native gold from amphibolite facies domains contains significant Ag, precluding that it formed by the thermal decomposition of aurostibite. Therefore, the spatial variations in occurrence of Au phases reflect the deposition of Au during the peak metamorphism. Higher metamorphic grade rocks are extended westward along the auriferous shear zones, suggesting heat transfer along shear zones by hydrothermal fluids. This suggests a magmatic heat source to the east for auriferous hydrothermal activity. Hence, Au mineralization likely took place during the emplacement of the marginal phase of the Trout Lake batholith. The lack of Type II inclusions in high Au grade breccias is interpreted as a result of the selective loss of H2O following phase separation. Phase separation is probably the most important mechanism for the mineralization of high Au grades (>500 g/t Au) at the mine. The gold-related wallrock alteration at the Campbell Mine is similar to that in other Archean Au deposits hosted by lower amphibolite facies mafic rocks, such as the Coolgardie goldfields (Knight et al., 2000) and the Norseman district deposits (Mueller, 1992). The P-T conditions for the auriferous hydrothermal activity at many Archean lode-type deposits define a low P and high T path. The path indicates much higher temperatures than the Archean geotherm, suggesting either a contribution of heat from contemporaneous magmas to auriferous fluids, or rapid transfer of heat from deep levels. For syn-metamorphic Au deposits, the data support a magmatic heat source. This is in accord with the low P/high T conditions of the metamorphism accompanying the Au deposits. For post-peak metamorphic deposits, the data suggest transport of heat from a source external to the greenstone sequence. (Abstract shortened by UMI.)

The Sudbury Structure, Ontario, is the remnant of a 1.85 Ga old impact crater, 200--250 km in diameter. Erosion and tectonism have affected the Sudbury Structure and resulted in considerable brittle and ductile deformation, and the removal of the surface expression of the crater structure and all exterior deposits typical of many terrestrial impact structures. However, substantial amounts of the interior deposits, including the craterfill products, have been preserved within the Sudbury Basin. Although most workers acknowledge an impact origin for the Sudbury Structure, the origin of the Sudbury Igneous Complex (SIC), located inside the Sudbury Structure, remains controversial. The objectives of this study are to elucidate the division of the SIC into lithologically separate phases and to understand their relation to impact and endogenic igneous processes by using physical, chemical and computer methods, and to model the genesis of the SIC. The SIC is a 2.5--3.0 km thick, ∼60 x 27 km elliptical igneous-rock body, consisting of four major lithologies (top to base): granophyre, quartz gabbro, norite, and the so-called contact sublayer. All these lithologies are continuous across the complex, except for the contact sublayer. Modal compositions reveal that the current nomenclature is improper. According to the IUGS classification, "quartz gabbro" samples should be classified as quartz monzogabbros and "norite" samples as quartz gabbros or quartz monzogabbros. In view of these observations, an updated terminology is proposed (top to base): upper unit, transition zone, middle unit, lower unit, and contact sublayer. Gradational mineralogical and geochemical variations between the SIC lithological units are evidence of a single melt system for the SIC. The occurrence of primary hydrous minerals, deuteric alteration, and abundant micrographic and granophyric intergrowths demonstrate that this melt was rich in H 2O. The intergrowths and other far-from-equilibrium textures are likely due to rapid crystallization as a result of a large undercooling caused by the exsolution of a volatile phase. The SIC differs from other known terrestrial impact melt sheets only by its great thickness and its chemical layering. It is concluded that the SIC is a differentiated impact melt sheet, the only one identified on Earth to date.

The boundary between the western and central domains of the Wabigoon subprovince has been considered to represent a ca. 2.7 Ga suture between juvenile Neoarchean volcanic rocks in the west and granitoid rocks with Mesoarchean ancestry in the central Wabigoon. The nature and timing of interaction between these two terranes was examined southeast of the Sturgeon Lake greenstone belt within the central Wabigoon, where amphibolite-facies supracrustal remnants are dismembered by Neoarchean plutonic rocks and shear zones. Of the 4 preserved ductile deformation fabrics, D1 and D2 are bracketed by a 2718 +/- 7 Ma tonalite gneiss and crosscutting 2715 Ma tonalite dyke. The main penetrative S3 foliation affects most units, including quartz-rich sandstone deposited after 2701 Ma. A 2697 Ma granodiorite dyke cutting S3 in mafic and metasedimentary rocks provides a lower bracket on D3. Regional implications can be drawn from the observation of 2725--2715 Ma D1 and D2 deformation events in the central Wabigoon. These constraints overlap with an early deformation event in the Pipestone Lake area of the western Wabigoon (2727--2712 Ma; Edwards and Stauffer, 1999). (Abstract shortened by UMI.)

The ultramafic member of the Lower Ordovician Betts Cove Ophiolite Complex forms an elongate fault bounded belt on the eastern side of the Baie Verte Peninsula. The Betts Big Pond area encompasses the transition between the least altered layered cumulate rocks of the southern part of the ultramafic belt and the metasomatized rocks of the northern part of the ultramafic belt and includes serpentinite, serpentine-carbonate rocks, and talc-carbonate rocks. Au concentrations up to 1300 ppb occur in hematite bearing talc-carbonate rocks in the northern part of the Betts Big Pond area. The occurrence of Au in talc-carbonate racks is consistent with its deposition from Au(HS)$\sb2\sp-$ due to fluid oxidation as a result of the carbonatization of magnetite in the absence of Fe-bearing serpentine. The Au occurrence in serpentinite is consistent with Au deposition from Au(HS)$\sb2\sp-$ as the serpentinizing fluid reacted with a chromite lens. The Long Pond and Arrowhead Pond veins in the northern part of the Betts Cove Complex are interpreted to have formed from fluids of mutually similar composition. C and O isotopic compositions of vein carbonates from the northern Betts Cove Complex are similar to the isotopic composition of C and O of magnesite from talc-carbonate rocks and serpentine-carbonate rocks of the Betts Big Pond area. Talc-carbonate rocks within the alteration halo surrounding Au-vein mineralization at Arrowhead Pond is enriched in SiO$\sb2$; Otherwise it is chemically similar to talc-carbonate rocks. The similarity in chemical and isotopic compositions suggests that Au-vein mineralization may have been emplaced at a similar time as that in talc-carbonate rock in the Betts Big Pond area. (Abstract shortened by UMI.)

The Timiskaming Group is a late Archaean syn-tectonic lithological unit which lies unconformably on greenstone-belt volcanic rocks and consists of an alluvial-fluvial assemblage intercalated with alkalic volcanic rocks and a turbidite assemblage. The fine-grained sedimentary rocks of the alluvial-fluvial assemblage and turbidite north unit have similar mineralogical and chemical compositions such as high SiO$\sb2$, U, Th and total rare-earth elements (REE). The turbidite south unit has high Fe$\sb2$O$\sb{3(\rm tot)}$, MgO, TiO$\sb2$, Cr and Ni. Petrographic and geochemical examinations of clasts from the alluvial-fluvial assemblage indicate that the clasts are mostly igneous rocks with minor sedimentary rocks. Four major types of igneous clasts are recognized: calc-alkaline porphyries, trachytes, trondhjemites and tholeiitic basalts. Results indicate that the turbidite south unit is the oldest unit of the Timiskaming Group and the age of sedimentation is bracketed between 2685 Ma and 2700 Ma. It was derived from an undissected arc terrane uplifted during accretion. Sources for the turbidite south unit estimated from chemical compositions of shales are 12% rhyolite, 18% komatiite and 70% andesite. The alluvial-fluvial assemblage and turbidite north unit are inferred to have been derived from a dissected island arc after accretion, but before the unroofing of K-rich intrusions, which are presently extensively exposed. A source comprising 60% calc-alkaline porphyries, 20% trachytes and 20% tholeiitic basalts is estimated for the turbidite north unit from the chemical composition of shales. The distribution of trachyte clasts in the alluvial-fluvial assemblage only close to the Lander Lake-Cadillac Fault (LLCF) suggests that displacement along the fault may have created conduits for alkaline magmas. Similar lithology of conglomerates north and south of the fault suggests that the alluvial-fluvial assemblage was deposited in a pull-apart basin after juxtaposition of two tectonic blocks along the fault between 2685 and 2677 Ma. (Abstract shortened by UMI.)

One of the world's most productive gold camps is located along the major east-trending Larder Lake fault (LLF), which extends approximately 250km from Val d'Or to Kirkland Lake. The western portion of the LLF consists of a 60 km long narrow (less than 5 km wide) and sinuous deformation zone commonly referred to as the Kirkland Lake-Larder Lake fault zone (KLF). The occurence of two distinct suites of magmatic rocks, syenitic and granitic, in and around the KLF indicates a magmatic duality. It is possible to identify three distinct magmatic domains defined by mode of emplacement, minerology and geochemistry. Mineral chemistry indicates that rocks from both suites evolved under oxidizing conditions in domains 1 and 3. Rare earth element compositions indicate a similar upper mantle source for both magmatic suites. Major element compositions confirm the shoshonitic nature of the syenitic suite, while the granitic suite is comparable to the sanukitoid suite (high-Mg,-K, -LILE andesites). Both the syenitic and granitic suites originate from an upper mantle source that was very probably modified a relatively short time before by fluids and/or melts derived from a subducted slab. The Kirkland Lake area is marked by an early transtensive phase when syenitic and granitic rocks were emplaced in extensional fractures associated to sinistral strike-slip faulting. Uplift of domain 3 and reverse faulting along the Kirkland Lake main break (KLMB) and the LLF are associated with a later transpressive phase; it was during this phase that gold deposits were formed. The structural, mineralogical and geochemical evidence fit in a tectomagmatic model where oblique convergence and accretion dominate.

The scarcity of water resources in Jordan poses difficulties for the development of the country and its relationship with its neighbours. Thermal groundwaters recently identified in the northern part of the country represent a 40 MCM/y resources for exploitation to meet the increasing demand for water. These thermal groundwaters are found in three well fields (Mukhebeh, JRV and Ramtha) and were investigated to determine their recharge origin, mean subsurface residence times, and the source of heat. They discharge in the northern part of Jordan Rift Valley and the rifted Yarmouk Valley, which are low elevation (50 to 150 m below sea level) zones of recent tectonism and volcanic activity. The range of temperatures is 30 and 56$\sp\circ$C and salinities vary between 500 and 2500 mg/l. Non-thermal groundwaters within the study area have also been studied. In particular shallow groundwater in adjacent highlands region (Ajloun Mountains) are examined to determine their role in recharge to those regional flow systems. The principal aquifer is the Upper Cretaceous B2/A7 group, a package of carbonate formations with high kerogen content at depth. This aquifer outcrops in the Ajloun Mountains and flanking regions and is confined by overlying marls in the down gradient regions. A deeper sandstone aquifer underlies the study area and hosts thermal groundwater which was sampled in the Ramtha area. The major geochemical processes in the subsurface have generated various geochemical facies in the thermal waters. These include carbonate dissolution to calcite saturation in the recharge areas. The thermal groundwater in Mukhebeh and JRV well fields are found to be chemically similar to the carbonate groundwater from Ajloun mountains recharge area. All thermal waters are characterized by sulphate reduction, driven by oxidation of kerogen. Sulphate is of marine evaporite origin dissolved from within the aquifer with a component of volcanogenic sulphur. Some thermal waters have also Na-Cl salinity component related to evaporite dissolution. The thermal waters are of meteoric provenance, originating as rain falling over the carbonate highlands in Jordan and Syria. The $\delta\sp $O and $\delta$D isotopic data show that all thermal groundwaters are largely associated with Eastern Mediterranean Meteoric Water Line, signifying recharge under the climate regime which dominates today in Jordan. The exception is groundwater from the deep sandstone aquifer which is associated with Global Meteoric Water Line, signifying recharge during Pleistocene time. The isotopic composition of groundwater suggests two distinct recharge areas for the Mukhebeh well field: Ajloun Mountains (Jordan) and Mount Hermon (Syria). (Abstract shortened by UMI.)