Elizabeth C Turner

• PhD
• Professor (Full) at Laurentian University

The Rapitan Group (Northwest Territories, Canada) includes banded iron formation (BIF), an unusual sediment type that is associated with late Neoproterozoic glaciations, in this case, the early Cryogenian Sturtian glaciation. New non‐traditional stable isotope data from jasper and hematite iron formation (IF) from the Cranswick River area contribut...

Siderite and baryte are common non-sulphide phases in sedimentary exhalative (SEDEX) deposits, but their formation remains poorly understood. Siderite is important as an exploration vector in some deposits, whereas baryte is important as a S source in some deposits. The past-producing Walton deposit (Nova Scotia, Canada) consists of two ore types:...

The Mississippian (Viséan) Windsor Group of Atlantic Canada consists of a lower carbonate unit overlain by a thick succession of evaporite, clastic, and carbonate rocks. It hosts numerous Zn-Pb deposits, including the Scotia (formerly Gays River deposit), Walton and Jubilee deposits in Nova Scotia, and a number of occurrences on the Port au Port Pe...

Walton is a past-producing Ag-Pb-Zn-Cu sulphide carbonate-hosted deposit (0.41 Mt; head grade of 350 g/t Ag, 4.28% Pb, 1.29% Zn, and 0.52% Cu) hosted primarily by sideritized Viséan Macumber For-mation limestone and juxtaposed to and replacing a barite ore body (4.5 Mt of >90% barite). Previous work demonstrated that mineralization came from heated...

Newfoundland Zinc Mines is a past-producing Zn-Pb sulphide carbonate-replacement deposit (7.2 Mt of 8% Zn) hosted primarily by the Upper Ordovician Catoche Formation dolostone. Previous work demonstrated that mineralisation occurred by the late Devonian from heated (<185°C for sphalerite), saline (20-27 wt. % equiv. NaCl) fluids. To refine the char...

Ore in the Kamoa-Kakula deposits (Democratic Republic of Congo) is dominated by fine-grained Cu sulfides disseminated in Cryogenian diamictite matrix and siltstone, commonly with coarsely crystalline sulfide-gangue ‘caps’ and ‘beards’ on larger clasts. In addition to sedimentary material, ore-zone matrix contains hypogene Cu-sulfides, and ore-stage...

Geochemical and geochronological data from the Pinguicula Group and unit PR1 of the lower Fifteenmile Group (Yukon, Canada) provide information on sediment provenance and timing of break-up of supercontinent Columbia and seaway development on Laurentia’s northwestern margin. The older unit PR1, in the Coal Creek inlier, has a near-unimodal detrital...

The Polaris district in Canada’s Arctic Archipelago contains numerous carbonate rock-hosted Zn + Pb showings and rare, anomalous Cu showings in a 450- × 130-km area. As in many metallogenic districts, a genetic relationship between the mined deposit and surrounding showings has been assumed but not tested. This study uses an in situ, multianalytica...

The papers contained in this bulletin provide a comprehensive summary and updated understanding of the onshore geology and evolution of Baffin Island, the Labrador-Baffin Seaway, and surrounding onshore regions. This introductory paper summarizes and links the geological and tectonic events that took place to develop the craton and subsequent Prote...

This study addresses marine palaeoredox conditions of the mid-Neoproterozoic by analysing the Mo isotope, trace element, and U-Th-Pb isotope compositions of shallow water microbial carbonate, deep water pelagic carbonate, and shale from the Stone Knife Formation (SKF) in NW Canada. The U-Th-Pb isotope SKF systematics of reef microbialite carbonates...

The Scotia Mine deposit (the ‘Gays River deposit’; Nova Scotia, Canada) is a Zn-Pb sulphide carbonate-replacement deposit (reserves 13.6 Mt @ 3.09% ZnEq, resource 25.5 Mt @ 2.84% ZnEq; ScoZinc report) hosted by the Viséan Gays River Formation dolostone. Previous work, conducted over 25 years ago, demonstrated that mineralization occurred ca. 300 Ma...

The early evolution of the Misty Creek embayment (MCE), a prominent, northwest-trending sub-basin of the economically important Selwyn basin, is poorly understood. The abrupt contact between Cambrian Stage 4 (traditional lower Cambrian) carbonate ramp strata of the Sekwi Formation and overlying Miaolingian (traditional middle Cambrian) deep-water,...

Molecular phylogeny indicates that metazoans (animals) emerged early in the Neoproterozoic era1, but physical evidence is lacking. The search for animal fossils from the Proterozoic eon is hampered by uncertainty about what physical characteristics to expect. Sponges are the most basic known animal type2,3; it is possible that body fossils of hithe...

The Mesoproterozoic is an important era for the development of eukaryotic organisms in oceans. The earliest unambiguous eukaryotic microfossils are reported in late Paleoproterozoic shales from China and Australia. During the Mesoproterozoic, eukaryotes diversified in taxonomy, metabolism, and ecology, with the advent of eukaryotic photosynthesis,...

The geological time scale before 720 Ma uses rounded absolute ages rather than specific events recorded in rocks to subdivide time. This has led increasingly to mismatches between subdivisions and the features for which they were named. Here we review the formal processes that led to the current time scale, outline rock-based concepts that could be...

Four first-order (Hadean, Archean, Proterozoic and Phanerozoic eon) and nine second-order (Paleoarchean, Mesoarchean, Neoarchean, Paleoproterozoic, Mesoproterozoic, Neoproterozoic, Paleozoic, Mesozoic and Cenozoic era) units continue to provide intuitive subdivision of geological time. Major transitions in Earth’s tectonic, biological and environme...

Carbonate successions older than the 800 Ma Bitter Springs isotope anomaly are sparse and this time is consequently poorly understood. The Shaler and Mackenzie Mountains supergroups of northwestern Canada, however, contain thick ca. 1050-750 Ma carbonate successions recording both deep- and shallow-water depositional environments that are interpret...

Understanding the Mesoproterozoic and younger structural history of the Eclipse Sound/Pond Inlet area is essential for the interpretation of its Archean to Paleoproterozoic geological history and could have important implications for mineral and petroleum exploration models in the northern Baffin Bay area. The identification of potentially active f...

Accurate and precise geochronology using the Re-Os isotopic system in pyrite is an invaluable tool for developing and confirming genetic models of ore systems. However, as a bulk method, the results produced by pyrite Re-Os geochronology are commonly complex, and many imprecise isochrons exist in the literature. Using LA-ICPMS methods it is now pos...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Fungi are crucial components of modern ecosystems. They may have had an important role in the colonization of land by eukaryotes, and in the appearance and success of land plants and metazoans1–3. Nevertheless, fossils that can unambiguously be identified as fungi are absent from the fossil record until the middle of the Palaeozoic era4,5. Here we...

The diversification of acritarchs (organic-walled vesicular microfossils of unknown affinity), filamentous, and multicellular microorganisms, happened during a time of profound environmental, biological, and ecological change. The Mesoproterozoic to Neoproterozoic transition is a key interval, notably for eukaryotic organisms. New assemblages of or...

The metallogenetically important Cornwallis Zn district, in Canada's Arctic islands, includes the past-producing Polaris mine and numerous base-metal showings, including Storm copper. Storm is unusual because it is near the southern limit of the district, is Cu- versus Zn-dominated, is overlain and underlain by red sandstone, and is hosted by Silur...

The predominant spatial control on sulfide orebodies at two significant base metal deposits, Kipushi (Democratic Republic of Congo) and Gayna River (Canada), is the architecture of Neoproterozoic carbonate lithofacies. At the Gayna River Zn camp, surface and subsurface mineralization is limited to the peripheries of giant pinnacle reefs of an unusu...

Ancient carbonate rocks commonly contain numerous post-depositional phases (carbonate minerals; quartz) recording successive diagenetic events that can be deciphered and tied to known or inferred geological events using a multi-pronged in situ analytical protocol. The framework voids of large, deep-water microbial carbonate seep-mounds in Arctic Ca...

We present detrital zircon U-Pb data from mainly fluvial sandstones of the Mackenzie Mountains Supergroup, Yukon (four samples), and the Shaler Supergroup, Northwest Territories (seven samples). The high similarity of data sets from widely separated units supports long-held stratigraphic correlations between the late Mesoproterozoic Neoproterozoic...

The Mesoproterozoic Ikpiarjuk Formation (Borden Basin, Nunavut) consists of a series of very large (>200 m thick; kms diameter) dolostone mounds that accumulated on the floor of a restricted basin. The mounds are isolated from contemporaneous shallow-water carbonate rocks, accumulated at the same time as black shale in deep-water regions of the bas...

The Mesoproterozoic (1.1 Ga) Borden Basin (Nunavut) contains strata of the Bylot Supergroup, including extremely large, deep-water dolostone mounds (Ikpiarjuk Formation) whose distribution is controlled by syndepositional faults. The mounds formed as a result of fluid-venting (groundwater) along subaqueous faults during black shale deposition (Hahn...

The age and origin of the past-producing Nanisivik carbonate-hosted Zn-Pb deposit in Nunavut, Canada, have been controversial for decades. Various direct and indirect dating methods have produced results ranging from Mesoproterozoic to Ordovician in age, and previous studies of the mineralising fluids have suggested that the fluids were anomalously...

This paper challenges the conventional interpretation of a major, economically important Mesoproterozoic intracratonic rift system as a group of aulacogens, proposing instead that they are rifts that developed in response to far-field stress caused by continent–continent collision (impactogens) during supercontinent assembly. The tectonostratigraph...

The Mesoproterozoic Pinguicula Group (<1.38 Ga) is exposed in the Wernecke and Hart River inliers in northern Yukon, Canada. The Pinguicula Group records deposition of non-cyclic siliciclastic and carbonate strata on low-energy slopes affected by rare high-energy deposits in a tectonically active epicratonic setting. The succession is ∼1.4 km thick...

Paleogeographic data indicate that the Neoproterozoic Rapitan Group accumulated in two spatially related, silled basins during the first mid-Neoproterozoic glacial episode (ca. 711 Ma), yet the controls on glaciation, reason for basin development, spatio-temporal relationships among stratigraphic units, and constraints on iron formation deposition...

Thick sulfate evaporite accumulations are absent from Proterozoic strata between ca. 2000 and ca. 1000 Ma, and detailed sedimentologic, stratigraphic, and geochemical data for the oldest Neoproterozoic thick marine sulfate evaporite successions are largely lacking. The middle Neoproterozoic Ten Stone Formation (Little Dal Group, Northwest Territori...

The Mesoproterozoic (1.1 Ga) Borden Basin contains extremely large, deep-water dolostone seep mounds(Ikpiarjuk Formation) whose distribution is controlled by faults. Four mounds were investigated alongmeasured stratigraphic sections. Petrographic study revealed several depositional components, and amixture of at least two distinct carbonate sources...

Victoria Island, in Arctic Canada, is one of the largest islands in the world, but its geology has remained largely unmapped and unstudied owing to its remoteness. Base-metal and hydrocarbon showings have been reported from the island, but the origin and prospectivity of these showings remain enigmatic. Regionally extensive, void-filling Phanerozoi...

Pre-Cambrian atmospheric and oceanic redox evolutions are expressed in the inventory of redox-sensitive trace metals in marine sedimentary rocks. Most of the currently available information was derived from deep-water sedimentary rocks (black shale/banded iron formation). Many of the studied trace metals (e.g. Mo, U, Ni and Co) are sensitive to the...

Two supercontinents have been proposed for the latter half of the Precambrian: Columbia (or Nuna) from ca. 1.9-1.3 Ga, and Rodinia from ca. 1.1-0.75 Ga. In both supercontinents, Laurentia and Australia are regarded as probable neighbours, although their relative positions are contentious. Here we use detrital zircons ages from unit PR1 of the lower...

Numerous occurrences of carbonate-hosted (or Mississippi Valley-type) Zn±Pb mineralization are present in Neoproterozoic to Devonian rocks of the Mackenzie Mountains zinc district (Northwest Territories, Canada). Detailed stratigraphic and petrographic studies of showings in the Early Cambrian Sekwi Formation, a preferred host of mineralization, ha...

Despite the presence of known economic resources in Canada's Arctic archipelago, Victoria Island remains understudied. This study addresses the fluid history and economic potential of two major carbonate units on Victoria Island by integrating fluid inclusion microthermometry with SEM-EDS analysis of evaporate mounds. Three cements containing fluid...

The Mackenzie and eastern Selwyn Mountains, Northwest Territories, Canada, are the northeast expression of the Cordilleran orogen and have a geologic history that spans the last one billion years. The region has undergone a diverse tectonic evolution, which is reflected in an equally diverse collection of mineral deposits and prospects. More than 3...

The Mesoproterozoic Borden, Hunting-Aston, Fury and Hecla, and Thule basins, collectively known as the Bylot basins, are a series of sub-parallel extensional depressions associated with the Mackenzie igneous event at ∼1270 Ma. In the Borden basin, basal strata of the Eqalulik Group are dominated by tholeiitic basaltic rocks and siliciclastic sandst...

The Arctic Bay Formation (Nunavut, Canada) represents a late Mesoproterozoic muddy terrigenous ramp and contains >200 m of black shale. The formation was studied in order to decipher the tectonostratigraphic and geochemical evolution of the basin, address the origin of metal enrichment, and determine whether this frontier basin has the potential to...

Neoproterozoic iron formations record an unusual and apparently final recurrence of this sediment type after a hiatus of more than one billion years. Despite the unusual environmental conditions that led to their formation, specifically their association with glaciogenic deposits, Neoproterozoic iron formations have strongly influenced models for t...

The late Meso or early Neoproterozoic Pinguicula Group, Wernecke Mountains, Yukon, is a siliciclastic and carbonate succession deposited on an angular unconformity developed on the Wernecke Supergroup. The group consists of three units. Unit A consists of a fining-upward conglomerate and sandstone unit overlain by a monotonous siltstone succession....

The Mackenzie Mountains Supergroup in NWT is formalised in this and a companion paper. The supergroup includes carbonate rocks of the Tabasco Formation (new), mudstones, sandstones and minor carbonate rocks of the Tsezotene Formation, sandstones, mudstones and carbonate rocks of the Katherine Group, and carbonate rocks, evaporite rocks and mudstone...

Field mapping of carbonate-hosted base metal showings in the Milne Inlet graben of the Mesoproterozoic Borden basin, Nunavut, has identified the main geologic settings for mineralization in the district that hosts the past-producing Nanisivik deposit. All known showings are associated with faults, fractures, or dikes; these include major, graben-bo...

Early Neoproterozoic reefs (older than 779, younger than 1083 Ma) contain a carbonate rock texture, already familiar from sponge-rich Phanerozoic limestones, characterized by authigenic Ca carbonate and irregular, secondary voids containing internal sediment (polymud fabric). In Holocene sediment, this texture develops by calcification of degrading...

Zn-Pb deposits at Gayna River, NWT are predominantly concentrated in the informal 'Grainstone formation', a dolostone of the early Neoproterozoic Little Dal Group (Mackenzie Mountains Supergroup). Previous work showed that the mineralisation (inferred 50 Mt combined from numerous zones; 5 percent combined Zn+Pb) is fracture-controlled and spatially...

The Milne Inlet Graben is a trough in the aulacogenic Borden Basin, one of several Mesoproterozoic basins that constitute the Bylot Basins. It contains the Nanisivik ore-body as well as numerous other showings spread over an area of 250 x 100 km. Almost all showings are hosted by a dolostone formerly known as the Society Cliffs Formation, which is...

The Mackenzie Mountains Zn district includes over 200 Zn(-Pb) showings hosted by Neoproterozoic to Lower Paleozoic carbonate rocks. This study addresses three of over 30 known showings in the Lower Cambrian Sekwi Formation, over 130 km of strike length (AB, TIC and Palm showings, from NW to SE). Property-scale mapping and detailed stratigraphy of m...

Existing stratigraphic nomenclature, lithologic descriptions, and geological interpretations for an economically important Mesoproterozoic dolostone in the Milne Inlet Graben, Borden Basin, Nunavut, do not adequately portray its unusual facies or their spatio-temporal configuration. Four new stratigraphic units are introduced to replace this dolost...

Early Neoproterozoic reefs (older than 779, younger than 1083 Ma) contain a carbonate rock texture, already familiar from sponge-rich Phanerozoic limestones, characterized by authigenic Ca carbonate and irregular, secondary voids containing internal sediment (poly-mud fabric). In Holocene sediment, this texture develops by calcification of degradin...

The early Neoproterozoic Mackenzie Mountains supergroup (MMSG; similar to 4 km thick, < 1083 Ma, > 779 Ma) was deposited in a large but poorly understood basin. Analysis of new and existing stratigraphic data reveals unexpected, abrupt changes in thickness and lithofacies patterns in formation scale and smaller units over short distances parallel a...