Anthony R. Prave's research while affiliated with University of St Andrews and other places

Publications (128)

Article
Twenty-four composite samples of the fine-grained matrix of glacial diamictites deposited from the Mesoarchaean to Palaeozoic have been analysed for their silicon isotope composition and used to establish, for the first time, the long-term secular Si isotope record of the compositional evolution of upper continental crust (UCC). Diamictites with Ar...
Article
Nitrogen isotopes and abundances in sedimentary rocks have become an important tool for reconstructing biogeochemical cycles in ancient ecosystems. There are two archives of nitrogen in the rock record, namely kerogen‐bound amines and silicate‐bound ammonium, and it is well documented that the isotopic ratios of these two archives can be offset fro...
Article
Carbonate rocks are important paleo-environmental records, with bulk chemical and isotopic compositions commonly used to deduce temperatures, redox conditions, etc. Diagenetic (re)crystallization of clasts and cements is common, may perturb the chemical and isotopic systems typically interpreted to reflect conditions at the timing of deposition, ma...
Article
Carbon, sulfur and oxygen isotope profiles in Silurian strata of the Baltoscandian Basin (Estonia), coincident with the Ireviken Bioevent, provide insights into basin-scale and platform-specific depositional processes. Paired carbon isotope records preserve a positive isotope excursion during the early Wenlock, coincident with faunal turnover, yet...
Article
Full-text available
Bakakas Mayika et al. (2020) and Ossa Ossa et al. (2018) reported, on a stratigraphical interval of the Francevillian group as recovered in cores LST12 and LST1, a δ13Ccarb trend of highly positive values (8-10‰) that descend towards 0‰. Whereas Bakakas Mayika et al. (2020) assigned to this Francevillian strata a continuous transgressive trend from...
Article
Full-text available
The Palaeoproterozoic Lomagundi-Jatuli Event (LJE) is generally considered the largest, in both amplitude and duration, positive carbonate C-isotope (δ ¹³ C carb ) excursion in Earth history. Conventional thinking is that it represents a global perturbation of the carbon cycle between 2.3–2.1 Ga linked directly with and in part causing the postulat...
Preprint
Full-text available
The Palaeoproterozoic Lomagundi-Jatuli Event (LJE) is the largest positive carbonate C-isotope ( δ13Ccarb) excursion in Earth history. Conventional thinking is that it represents a perturbation of the global C cycle between c. 2.3–2.1 Ga linked directly to the postulated Great Oxidation Event. Here we show that the LJE worldwide is, in fact, entire...
Article
The origin of the Stac Fada Member has been debated for decades with several early hypotheses being proposed, but all invoking some connection to volcanic activity. In 2008, the discovery of shocked quartz led to the hypothesis that the Stac Fada Member represents part the continuous ejecta blanket of a meteorite impact crater, the location of whic...
Article
The 1.1 Ga Midcontinent Rift (MCR) is a thick volcanic-sedimentary succession that forms a curvilinear belt through central North America and crops out along its northern apex around Lake Superior. Sedimentary units of the MCR have been long interpreted as fluvial-lacustrine and invited a number of studies on the early evolution of life in non-mari...
Article
The Paleoproterozoic Francevillian succession of Gabon has figured prominently in concepts about Earth’s early oxygenation and genesis of a large positive excursion in carbon-isotope values, the Lomagundi-Jatuli event (LJE). Here we present a detailed study of a 139-m-long core of Francevillian rocks marked by carbonate δ13C (δ13Ccarb) values of 5‰...
Article
The c. 2.0 Ga Zaonega Formation of the Onega Basin (NW Russia) has been central in efforts to understand what led to the initial rise (Great Oxidation Event, GOE) and postulated fall in free atmospheric oxygen and associated high-amplitude carbon cycle excursions, the Lomagundi-Jatuli Event (LJE) and subsequent Shunga Event during Paleoproterozoic...
Article
Full-text available
The inability to resolve the exact temporal relationship between two pivotal events in Earth history, the Paleoproterozoic Great Oxidation Event (GOE) and the first “snowball Earth” global glaciation, has precluded assessing causality between changing atmospheric composition and ancient climate change. Here we present temporally resolved quadruple...
Article
Paleoproterozoic sedimentary successions are important archives of the redox evolution of Earth’s atmosphere and oceans. Efforts to unravel the dynamics of our planet’s early oxygenation from this archive rely on various geochemical proxies, including stable carbon and sulfur isotopes. However, ancient metasedimentary rocks often experienced early-...
Article
The Palaeoproterozoic Kerry Road deposit is one of the oldest examples of volcanogenic massive sulfide (VMS) mineralization. This small VMS deposit (∼500,000 tons grading at 1.2% Cu, 3.5% Zn) is hosted in amphibolite facies mafic-siliciclastic units of the c. 2.0 Ga Loch Maree Group, Scotland. Sulfide mineralization consists of pyrite and pyrrhotit...
Article
The pyrite sulfur isotope record of the 1.98 Ga Zaonega Formation in the Onega Basin, NW Russia, has played a central role in understanding ocean-atmosphere composition and inferring worldwide fluctuations of the seawater sulfate reservoir during the pivotal times of the Paleoproterozoic Era. That, in turn, has led to a concept that Earth's atmosph...
Article
The c. 1.1 Ga Copper Harbor and Nonesuch Formations of the Keweenawan Supergroup exposed along the Canadian-United States shorelines of Lake Superior are part of the surface exposures of the Laurentian Midcontinent Rift. These units have long been considered non-marine in origin and have figured prominently in ideas regarding the evolution of micro...
Article
A persistently aerobic marine nitrogen cycle featuring the biologically mediated oxidation of ammonium to nitrate has likely been in place since the Great Oxidation Event (GOE) some 2.3 billion years ago. Although nitrogen isotope data from some Neoarchaean sediments suggests transient nitrate availability prior to the GOE, these data are open to o...
Article
The Paleoproterozoic Zaonega Formation in Karelia, NW Russia, has played a key role in understanding the environmental conditions postdating the Great Oxidation and Lomagundi-Jatuli Events. Its carbonate- and organic-rich rocks (shungite) define the postulated Shunga Event representing an accumulation of very organic-rich sediments at c. 2 Ga and a...
Article
Full-text available
Zircon Hf evolutionary patterns are powerful tools to investiage magma petrogenesis and crustal evolution. The ¹⁷⁶Hf/¹⁷⁷Hf isotopic signature of a rock is particularly informative and can be used to derive an estimation of the time when mantle extraction and diagnose closed system reworking where successive samples through time define an Hf evoluti...
Article
The exceptionally organic-rich rocks of the 1.98 Ga Zaonega Formation deposited in the Onega Basin, NW Russia, have refined our understanding of Earth System evolution during the Paleoproterozoic rise in atmospheric oxygen. These rocks were formed in vent- or seep-influenced settings contemporaneous with voluminous mafic volcanism and contain stron...
Article
Full-text available
Major changes in atmospheric and ocean chemistry occurred in the Paleoproterozoic Era (2.5–1.6 billion years ago). Increasing oxidation dramatically changed Earth’s surface, but few quantitative constraints exist on this important transition. This study describes the sedimentology, mineralogy, and geochemistry of a two-billion-year-old and ~800 m-t...
Article
The late-Cryogenian – Ediacaran geological framework for South China is constructed principally from sedimentary successions preserved in the central and western regions of the Yangtze Block. New stratigraphic and carbonate-carbon isotope data allow us to extend that framework into the exhumed HP-UHP subduction complexes of the eastern Dabie and Su...
Preprint
Organic-rich rocks (averaging 2–5% total organic carbon) and positive carbonate-carbon isotope excursions (‰δC13>+5‰ and locally much higher, i.e. the Lomagundi-Jatuli Event) are hallmark features of Palaeoproterozoic successions and are assumed to archive a global event of unique environmental conditions following the c. 2.3 Ga Great Oxidation Eve...
Preprint
The end-Cryogenian glaciation (Marinoan) is portrayed commonly as the archetype of snowball Earth, yet its duration and character remain uncertain. Here we report U-Pb zircon ages for two ash beds from widely separated localities of the Marinoan-equivalent Ghaub Formation in Namibia: 639.29 ± 0.26 Ma and 635.21 ± 0.59 Ma. These findings verify, for...
Preprint
Existing radio-isotopic age constraints indicate that the global Palaeoproterozoic Lomagundi-Jatuli large, positive carbonate carbon isotopic excursion, with δ13C values >+5‰, occurred between 2.2 and 2.06 Ga. In the North Transfennoscandian Greenstone Belt of the Kola Peninsula, NW Russia, northern Norway and Finland, the Lomagundi-Jatuli Event is...
Article
The end-Cryogenian glaciation (Marinoan) is portrayed commonly as the archetype of snowball Earth, yet its duration and character remain uncertain. Here we report U-Pb zircon ages for two ash beds from widely separated localities of the Marinoan-equivalent Ghaub Formation in Namibia: 639.29 ± 0.26 Ma and 635.21 ± 0.59 Ma. These findings verify, for...
Article
New geological and geochronological data define four episodes of volcanism for the Lake Tana region in the northern Ethiopian portion of the Afro–Arabian Large Igneous Province (LIP): pre-31 Ma flood basalt that yielded a single 40Ar/39Ar age of ; thick and extensive felsic ignimbrites and rhyolites (minimum volume of ) erupted between and (U–Pb CA...
Article
A variety of carbonates of different geneses, as indicated by petrography and geochemistry, are found throughout 400m of the volcano-sedimentary rocks of the Zaonega Formation of Palaeoproterozoic age in the Onega Basin of Fennoscandia. Following intensive sampling and analysis of varied calcites from drillcore recovered during the ICDP FAR-DEEP pr...
Article
Two Palaeoproterozoic events have particularly interested Earth scientists. These are the global Lomagundi–Jatuli Event, the greatest magnitude positive carbonate carbon isotope excursion in Earth history, and the Shunga Event, the world’s largest organic carbon burial event. Analysis of newly acquired high-resolution C–O isotope data and U–Pb zirc...
Article
Full-text available
Two Palaeoproterozoic events have particularly interested Earth scientists. These are the global Lomagundi–Jatuli Event, the greatest magnitude positive carbonate carbon isotope excursion in Earth history, and the Shunga Event, the world’s largest organic carbon burial event. Analysis of newly acquired high-resolution C–O isotope data and U–Pb zirc...
Article
Full-text available
Organic-rich rocks (averaging 2–5% total organic carbon) and positive carbonate-carbon isotope excursions ( and locally much higher, i.e. the Lomagundi-Jatuli Event) are hallmark features of Palaeoproterozoic successions and are assumed to archive a global event of unique environmental conditions following the c. 2.3 Ga Great Oxidation Event. Here...
Article
Full-text available
Detrital zircons from modern sediments display an episodic temporal distribution of U-Pb crystallization ages forming a series of ‘peaks’ and ‘troughs’. The peaks are interpreted to represent either periods of enhanced generation of granitic magma perhaps associated with mantle overturn and superplume events, or preferential preservation of contine...
Data
The first appearance of skeletal metazoans in the late Ediacaran (~550 million years ago; Ma) has been linked to the widespread development of oxygenated oceanic conditions, but a precise spatial and temporal reconstruction of their evolution has not been resolved. Here we consider the evolution of ocean chemistry from ~550 to ~541 Ma across shelf-...
Article
Boron isotope patterns preserved in cap carbonates deposited in the aftermath of the younger Cryogenian (Marinoan, ca. 635 Ma) glaciation confirm a temporary ocean acidification event on the continental margin of the southern Congo craton, Namibia. To test the significance of this acidification event and reconstruct Earth's global seawater pH state...
Article
The greenschist-facies late Mesoproterozoic Bandak succession in southern Norway consists of interlayered quartzites and meta-volcanic rocks with well preserved depositional and structural relations, which when combined provide important information on the late Mesoproterozoic continental margin of Baltica prior to the assembly of the supercontinen...
Article
Full-text available
The Kingston Peak Formation is a diamictite-bearing succession that crops out in the Death Valley region, California, USA. An exceptionally thick (>1.5 km) outcrop belt in its type area (the Kingston Range) provides clear insights into the dynamics of mid-Cryogenian ('Sturtian') ice sheets in Laurentia. Seven detailed logs allow the lateral and ver...
Article
A marked ocean acidification event and elevated atmospheric carbon dioxide concentrations following the extreme environmental conditions of the younger Cryogenian glaciation have been inferred from boron isotope measurements. Calcium and magnesium isotope analyses offer additional insights into the processes occurring during this time. Data from Ne...
Article
Full-text available
U-Pb detrital zircon ages from Mesoproterozoic and Cambrian siliciclastic units in west Texas (USA) constrain the depositional setting, provenance, and tectonic history of the region within a late Mesoproterozoic Grenville foreland basin and the early Paleozoic Sauk transgressive sequence. Two key units, the Hazel and Lanoria Formations, have detri...
Data
A marked ocean acidification event and elevated atmospheric carbon dioxide concentrations following the extreme environmental conditions of the younger Cryogenian glaciation have been inferred from boron isotope measurements. Calcium and magnesium isotope analyses offer additional insights into the processes occurring during this time. Data from Ne...
Data
Boron isotope patterns preserved in cap carbonates deposited in the aftermath of the younger Cryogenian (Marinoan, ca. 635 Ma) glaciation confirm a temporary ocean acidification event on the continental margin of the southern Congo craton, Namibia. To test the significance of this acidification event and reconstruct Earth's global seawater pH state...
Article
The Palaeoproterozoic Lomagundi–Jatuli Event is one of the largest magnitude and earliest known positive carbonate carbon isotope excursions, preserving δ13C values between + 5 and + 16‰ and even higher. It is recorded in sedimentary rocks on all continents bar Antarctica and spans stratigraphic thicknesses ranging from several to many tens of metr...
Article
Full-text available
All known forms of life require phosphorus, and biological processes strongly influence the global phosphorus cycle. Although the record of life on Earth extends back to 3.8billion years ago and the advent of biological phosphate processing can be tracked to at least 3.5billion years ago, the earliest known P-rich deposits appeared only 2billion ye...
Article
Full-text available
U-Pb detrital zircon data show that the East Mainland Succession, the presumed correlative of the Dalradian Supergroup in the Shetland Islands, Scotland, is dominated by Mesoproterozoic and Archaean material, with some Palaeoproterozoic detritus. The data are most consistent with derivation from eastern Laurentia, although western Baltica sources c...
Article
As part of the International Continental Scientific Drilling Program's Fennoscandian Arctic Russia-Drilling Early Earth Project (ICDP FAR-DEEP), Palaeoproterozoic diamictic and associated rocks were targeted and recovered in Hole 3A on the Kola Peninsula of NW Russia. In addition to the diamictites, carbonate sedimentary rocks and volcanic ash laye...
Article
Geology and stratigraphy of the Pechenga Greenstone Belt is described in detail in Chap. 4.2. The brief geological outline presented here provides a scientific context and background information for the FAR-DEEP implemented in this area.
Article
The main geological and stratigraphic features of the Onega Basin are discussed in Chap. 4.3. Given here is a brief geological outline to provide a scientific context and background information for the FAR-DEEP implemented in this area.
Article
The three-volume treatise, Reading the Archive of Earth’s Oxygenation, documents the scientific findings of the International Continental Drilling Program’s (ICDP) FAR-DEEP venture (Fennoscandian Arctic Russia – Drilling Early Earth Project). The major outcome of the drilling project was the successful recovery of a total of 3.5 km of pristine core...
Article
Full-text available
Neoproterozoic strata in Death Valley, California, contain eukaryotic microfossils and glacial deposits that have been used to assess the severity of putative snowball Earth events and the biological response to extreme environmental change. These successions also contain evidence for synsedimentary faulting that has been related to the rifting of...
Article
Existing radio-isotopic age constraints indicate that the global Palaeoproterozoic Lomagundi-Jatuli large, positive carbonate carbon isotopic excursion, with δ13C values >+5‰, occurred between 2.2 and 2.06 Ga. In the North Transfennoscandian Greenstone Belt of the Kola Peninsula, NW Russia, northern Norway and Finland, the Lomagundi-Jatuli Event is...
Article
The Neoproterozoic–Cambrian succession in the Death Valley region of the southwestern United States is among the best exposed and easily accessible in the world. The largest single exposure of these strata occurs in the Panamint Range on the west side of Death Valley, and it, although variably metamorphosed, contains the most complete sections of t...
Chapter
Full-text available
The Late Archaean-Early Palaeoproterozoic transition (2500–2000 Ma) represents a hallmark period when the Earth System experienced a series of fundamental upheavals. Among them, the most important was the establishment of an oxygen-rich atmosphere (sometimes referred to as the Great Oxidation Event) and the emergence of an aerobic biosphere. Associ...
Chapter
Full-text available
Hole 3A intersected the Polisarka Sedimentary Formation (Figs. 6.13, 6.14) in the western part of the Imandra-Varzuga Greenstone Belt (Figs. 6.1–6.3). The depositional age of the Polisarka Sedimentary formation is younger than c. 2442 Ma, which is the age of the underlying volcanic rocks of the Seidorechka Volcanic Formation (Amelin et al., 1995)....
Chapter
Many, if not all, of the long-term fluctuations in geological processes operating on Earth’s surface are tectonically driven and related to the interplay of plate tectonics and deep mantle dynamics resulting in supercontinental cycles and (super)plume events (Condie et al. 2001; Condie 2004). These processes include the amalgamation, dispersal, col...
Article
The ca. 2.0 Ga Zaonega Formation in the Onega Basin of NW Russia represents a deep-water, mixed siliciclastic–carbonate depositional system with voluminous mafic volcanism. It is typified by extremely organic-rich rocks (TOC > 40 wt%) and represents one of the earliest known episodes of oil/asphalt generation. These rocks have been inferred to arch...
Article
The ca. 2.0 Ga Zaonega Formation in the Onega Basin of NW Russia represents a deep-water, mixed siliciclastic-carbonate depositional system with voluminous mafic volcanism. It is typified by extremely organic-rich rocks (TOC > 40 wt%) and represents one of the earliest known episodes of oil/asphalt generation. These rocks have been inferred to arch...
Chapter
IntroductionThe Hadean EON: Formation of the Early EarthCrustal Evolution in the ArchaeanDevelopment of the Archaean Hydrosphere and the Evolution of LifeThe Archaean in the British Isles: The Lewisian ComplexSummaryReferences
Article
IntroductionEarly Palaeoproterozoic Rifting and Sedimentation: The Scourie Dykes and the Loch Maree GroupPalaeoproterozoic Orogeny: Laxfordian Deformation and Metamorphism of the Lewisian ComplexPalaeoproterozoic Subduction: Evolution of the Rhinns and Annagh Gneiss ComplexesMesoproterozoic Rifting: Deposition of the Stoer and Sleat GroupsLate Meso...
Conference Paper
Carbon isotopes of ICDP FAR-DEEP Hole 3A: alteration or a signal from atmospheric methane oxidation at the onset of the first Huronian glaciation?
Conference Paper
The Palaeoproterozoic Shunga event records significant organic-carbon accumulation in sediments correlated between the type-locality in northwest Russia's Onega Basin, the Francevillian series of Gabon, and Indian Palaeoproterozoic sections. The estimated burial of >25 x 10E +10 tonnes of C in the Shunga event is significant and hypotheses have sug...