Diamonds/Kimberlites (Project Leader: Aleksandar Miskovic)
In support of diamond exploration, a number of compilations have been undertaken using publicly available data including exploration data filed on mineral claims and from the scientific literature. These databases included KIDD - Kimberlite Indicator and Diamond Database, KIMC - Kimberlite Indicator Mineral Chemistry, SMAC - Slave Magnetics Compilation and KANDD - Kimberlite Anomaly Drillhole Database. In addition to the datasets for the Slave Province, compilations of comparable data for the Northern Mackenzie Valley (Northern Interior Platform) and the Churchill Province have now been initiated. We have recently completed a relational database for KIDD and KIMC which is now publically accessible through our NT GoMap and NT GoData web applications. This platform will facilitate the timely release of publicly available data in a far more efficient process than in the past as the relational database will be populated by mineral industry assessment report data as their period of confidentiality expires. We are presently working towards completion of a relational database for SMAC and KANDD and plan to make these available through NT GoMap and NT GoData in the coming years.
In addition to maintaining the KIMs data libraries, active research is being carried out to better understand the distribution and origin of "non-cratonic" kimberlites, lamprophyres and related rocks through the examination of occurrences outside of the Slave Province proper with particular focus on the petrology and mineral chemistry of ultramafic alkaline rocks in western Northwest Territories under the Paleozoic sedimentary cover (see Mt. Diatreme project below).
We are also engaged in isotopic fingerprinting of the Canadian sub-continental lithospheric mantle using oxygen isotope systematic in collaboration with colleagues at the University of Alberta in Edmonton. This will help further our understanding of the evolution of the sub-continental lithosphere in the global context (see the oxygen isotope survey below).
A collaborative research effort led by Dr. Hamish Sandeman and NTGO is being undertaken on field, petrographic, geochemical and geochronological aspects of a suite of lamprophyre rocks exposed at the south-western margin of the Slave craton. These dykes crosscut the Archean granitoids in the vicinity of the Stagg River and are linked to the latter stages of the Wopmay collisional orogen thus providing deep probes of the Paleoproterozoic Wopmay continental back-arc lithospheric mantle.
The NTGO diamond and metallogeny group has recently initiated a regional study aimed at geographically dispersed Paleoarchean cover sequence that overlies the basement of the Slave Craton. This unit consisting of quartzites and BIFs is unconformably overlain by greenstone belt mafic volcanics contemporaneous with the Yellowknife Supergroup. The petrologically mature quartzites from the cover sequence may be a significant repository of ancient (>2.8 Ga) heavy-mineral detritus from the Slave province including zircons and the Kimberlite Indicator Minerals (KIMs). While the cover sequence zircons provide age information related to crustal growth of the Slave Craton, geochemical information obtained from KIMs such as chromite, garnet, magnetite and perovskite will aid in identification of Archean kimberlitic sources which could develop into new exploration targets.
Suggestions for research partnerships with interested industry and university clients are welcome and should be directed at Aleksandar_Miskovic@gov.nt.ca.
