Camille A. Partin

University of Saskatchewan | U of S · Department of Geological Sciences

There are numerous Neoarchean metasedimentary rock packages in the Slave craton, and they serve as important archives of tectonic processes. Little is documented on the Neoarchean sedimentary packages of the Winter Lake greenstone belt of the central Slave craton, however, and their interpretation can aid in the understanding of the final stages of...

The Paleoproterozoic Belcher Group (ca. 2.0 to 1.83 Ga) occurs on the remote Belcher Islands of Hudson Bay in Nunavut, Canada. It includes nearly nine kilometres of well-preserved siliciclastic and carbonate sedimentary rocks, deposited initially in a marginal to shallow marine setting representing one of the first true continental shelf environmen...

The North American continent has a rich record of the tectonic environments and processes that occur throughout much of Earth history. This Memoir focuses on seven “turning points” that had specific and lasting impacts on the evolution of Laurentia: (1) The Neoarchean, characterized by cratonization; (2) the Paleoproterozoic and the initial assembl...

The Sunrise volcanogenic massive sulfide (VMS) deposit is a banded, polymetallic Zn-Pb-Cu-Ag sulfide lens hosted by felsic volcanic rocks of the Neoarchean Beaulieu River volcanic belt in the western Slave craton in the Sunset Lake area of the Northwest Territories, Canada. With historic indicated resources of 1.52 Mt at 5.99% Zn, 2.39% Pb, 0.08% C...

A δ²³⁸U record of changing ocean anoxia during OAE 2 is reconstructed using seawater derived U in pelagic marine sediments in the Portland #1 core in the south-central region of the Western Interior Seaway of North America. The peak negative excursion of 1.4‰ in authigenic sedimentary δ²³⁸U values is consistent with expansion of marine anoxia durin...

Geobiology explores how Earth's system has changed over the course of geologic history and how living organisms on this planet are impacted by or are indeed causing these changes. For decades, geologists, paleontologists, and geochemists have generated data to investigate these topics. Foundational efforts in sedimentary geochemistry utilized sprea...

Sediment-hosted Pb-Zn mineralization occurs in the Mârmorilik and Qaarsukassak formations of the Paleoproterozoic Karrat Group in arctic West Greenland. The timing and model of mineralization of the historical Pb-Zn Black Angel Mine in the Mârmorilik Formation and how it might be related to Pb-Zn mineralization in the nearby Qaarsukassak Formation...

The ~2.0-1.8 Ga (billion years old) Belcher Group on the Belcher Islands in Nunavut provide a unique opportunity for studying Paleoproterozoic geobiology. The Belcher Group includes a sequence of low metamorphic grade peritidal carbonate rocks that preserve putative microbiota, as first described by Hofmann and Jackson (1969). Microbial mats, inclu...

The Archean Winter Lake greenstone belt (WGB) in the Slave craton, located ~250 km northeast of Yellowknife in the Northwest Territories, has been underexplored relative to other supracrustal belts in the Slave craton, but shows potential for base-metal mineralization. It consists of lower greenschist to upper amphibolite grade mafic to felsic volc...

Neoarchean volcanic rocks of the Beaulieu River volcanic belt structurally overlie basement rocks of the Sleepy Dragon Complex (ca. 2.85 Ga), approximately 100 km east northeast of Yellowknife. The volcanic belt is comprised of complex lithofacies, including basalt, andesite, rhyolite, and associated volcaniclastic rocks, and hosts the Sunrise volc...

Numerous geologic proxies for Earth system processes track dramatic changes at the atmosphere-lithosphere or atmosphere-ocean interface during the early Paleoproterozoic Era. The presence of a geodynamic driver for these changes and how this might have affected the deeper lithosphere is more cryptic. Here we present temporally constrained δ ¹⁸ O an...

Open pits, which remain after uranium (U) mining operations cease, can form meromictic lakes that develop suitable conditions for the containment of dissolved and colloidal metals. In this study, the distribution and speciation of U, nickel (Ni), and arsenic (As) in the water column of two meromictic pit lakes was investigated at the decommissioned...

Geological evidence indicates that grounded ice sheets reached sea level at all latitudes during two long-lived Cryogenian (58 and ≥5 My) glaciations. Combined uranium-lead and rhenium-osmium dating suggests that the older (Sturtian) glacial onset and both terminations were globally synchronous. Geochemical data imply that CO 2 was 10 2 PAL (presen...

Sedimentary successions deposited near craton margins provide an opportunity to test hypotheses regarding nearest cratonic neighbors during deposition by reconstructing their sedimentary provenance. The Paleoproterozoic Murmac Bay Group, northern Saskatchewan, Canada, was deposited near the southwestern margin of the Rae craton between 1.93 Ga and...

Iron formations (IF) represent an iron-rich rock type that typifies many Archaean and Proterozoic supracrustal successions and are chemical archives of Precambrian seawater chemistry and post-depositional iron cycling. Given that IF accumulated on the seafloor for over two billion years of Earth's early history, changes in their chemical, mineralog...

Life requires a wide variety of bioessential trace elements to act as structural components and reactive centers in metalloenzymes. These requirements differ between organisms and have evolved over geological time, likely guided in some part by environmental conditions. Until recently, most of what was understood regarding trace element concentrati...

During the Sturtian and Marinoan "snowball Earth" episodes, ice cover is thought to have extended from polar to tropical latitudes. We test the supposition that such an extreme glacial climate, not repeated in the subsequent ~635 m.y. of Earth history, would have reduced the vigor of the hydrologic cycle and thus diminished sediment flux to the oce...

The proximity and positions of cratons constituting the western Canadian Shield prior to and during the Rhyacian Period (2.30-2.05 Ga) are poorly known. In the absence of paleomagnetic data, stratigraphic correlation and detrital zircon isotopic data from sedimentary successions can be used to constrain relative craton positions during their time o...

In the Rinkian belt of West Greenland, reworked Archaean gneisses are overlain by supracrustal successions of the Palaeoproterozoic Karrat Group, defined by Henderson & Pulvertaft (1967) as comprising two formations: the Qeqertarssuaq Formation and the Nûkavsak Formation. The group was later extended to include the Mârmorilik Formation (Henderson &...

Rock surface erosion by wildfire is significant and widespread but has not been quantified in southern California or for chaparral ecosystems. Quantifying the surface erosion of bedrock outcrops and boulders is critical for determination of age using cosmogenic radionuclide techniques, as even modest surface erosion removes the accumulation of the...

Sedimentary basins provide an archive of magmatic and tectonic events in their detrital zircon record, which can be dated and coupled with Hf isotopic data to reveal secular changes in the production of juvenile and evolved magmatism and track the history of orogenic events. The Rae craton, which forms a substantial portion of the northern Canadian...

Significance Redox-sensitive transition metals and their isotopes provide some of the best lines of evidence for reconstructing early Earth’s oxygenation history, including permanent atmospheric oxygenation following the Great Oxidation Event (GOE), ∼2.45−2.32 Ga. We show a shift from dominantly negative to permanently positive copper isotope compo...

Shortly after the initial rise of atmospheric oxygen in the Paleoproterozoic Era, a major perturbation occurred in the global carbon cycle, which is manifested as a long-lived positive carbon isotope excursion recorded in ∼2.22–2.06 Ga carbonate rocks, known as the Lomagundi Event. Beyond its significance for evolving seawater composition, this geo...

Carbon has two stable isotopes (12C and 13C) and one radiogenic isotope (14C). Carbon is the main constituent of the biosphere, rapidly recycled in the ocean–atmosphere system, and carbon isotope ratios are easily measured, and therefore stable carbon isotopes are widely used to trace the carbon cycle on Earth. Carbon isotopes may equally have util...

The concept of the Great Oxidation Event (GOE), during which atmospheric oxygen rose precipitously and perhaps to near-modern levels around 2.4–2.1 billion years ago (Ga), has become entrenched in our views on secular atmospheric evolution. Multiple proxies confirm a permanent shift towards more oxygenated conditions at some time near the Archean–P...

The partial pressure of oxygen in Earth's atmosphere has increased dramatically through time, and this increase is thought to have occurred in two rapid steps at both ends of the Proterozoic Eon (∼2.5-0.543 Ga). However, the trajectory and mechanisms of Earth's oxygenation are still poorly constrained, and little is known regarding attendant change...

The rise of atmospheric oxygen between 2.47 and 2.32 Ga undoubtedly had a significant impact on global biogeochemical cycles and particularly, the intensity of oxidative continental weathering. While the timing of atmospheric oxygenation is well-constrained, the redox -state of the deep ocean throughout the Proterozoic is less known. The distributi...

Redox-sensitive elements, such as U and Mo, are valuable proxies for oxygen availability in the ancient atmosphere and ocean. Scott et al. (2008) inferred three stages from the secular trend of Mo concentrations in organic matter-rich shales: 1) shales older than 2.2 Ga have low but above crustal average Mo concentrations; 2) shales ca. 2.2 Ga show...