Climate simulation of the latest Permian: Implications for mass extinction

This report presents the results of climate modeling research which indicates that elevated levels of carbon dioxide in the atmosphere at the end of the Permian period led to climatic conditions inhospitable to both marine and terrestrial life. The Permian-Triassic boundary (about 251 million years ago) was the time of the largest known mass extinction in Earth's history, when greater than ninety percent of all marine species, and approximately seventy percent of all terrestrial species, died out. The model, which used paleogeography and paleotopography correct for the time period, indicated that warm high-latitude surface air temperatures and elevated carbon dioxide levels may have resulted in slowed circulation and stagnant, anoxic conditions in Earth's oceans. The report also suggests that the excess carbon dioxide (and sulfur dioxide) may have originated from volcanic activity associated with eruption of the Siberian Trap flood basalts, which took place at the same time. Educational levels: Undergraduate lower division, Undergraduate upper division, Graduate or professional

The Global Ocean Biogeochemistry (GO-BGC) array of profiling floats to observe changing ocean chemistry and biology

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Matsumoto, G., Johnson, K., Riser, S., Talley, L., Wijffels, S., & Hotinski, R. The Global Ocean Biogeochemistry (GO-BGC) array of profiling floats to observe changing ocean chemistry and biology. Marine Technology Society Journal, 56(3), (2022): 122–123, https://doi.org/10.4031/mtsj.56.3.25.The Global Ocean Biogeochemistry (GO-BGC) Array is a project funded by the US National Science Foundation to build a global network of chemical and biological sensors on Argo profiling floats. The network will monitor biogeochemical cycles and ocean health. The floats will collect from a depth of 2,000 meters to the surface, augmenting the existing Argo array that monitors ocean temperature and salinity. Data will be made freely available within a day of being collected via the Argo data system. These data will allow scientists to pursue fundamental questions concerning ocean ecosystems, monitor ocean health and productivity, and observe the elemental cycles of carbon, oxygen, and nitrogen through all seasons of the year. Such essential data are needed to improve computer models of ocean fisheries and climate, to monitor and forecast the effects of ocean warming and ocean acidification on sea life, and to address key questions identified in “Sea Change: 2015–2025 Decadal Survey of Ocean Sciences” such as: What is the ocean’s role in regulating the carbon cycle? What are the natural and anthropogenic drivers of open ocean deoxygenation? What are the consequences of ocean acidification? How do physical changes in mixing and circulation affect nutrient availability and ocean productivity?Funding for the GO-BGC Array is provided through the NSF’s Mid-Scale Research Infrastructure-2 Program (MSRI-2; NSF Award 1946578)

Earliest Triassic microbialites in the South China Block and other areas; controls on their growth and distribution

Earliest Triassic microbialites (ETMs) and inorganic carbonate crystal fans formed after the end-Permian mass extinction (ca. 251.4 Ma) within the basal Triassic Hindeodus parvus conodont zone. ETMs are distinguished from rarer, and more regional, subsequent Triassic microbialites. Large differences in ETMs between northern and southern areas of the South China block suggest geographic provinces, and ETMs are most abundant throughout the equatorial Tethys Ocean with further geographic variation. ETMs occur in shallow-marine shelves in a superanoxic stratified ocean and form the only widespread Phanerozoic microbialites with structures similar to those of the Cambro-Ordovician, and briefly after the latest Ordovician, Late Silurian and Late Devonian extinctions. ETMs disappeared long before the mid-Triassic biotic recovery, but it is not clear why, if they are interpreted as disaster taxa. In general, ETM occurrence suggests that microbially mediated calcification occurred where upwelled carbonate-rich anoxic waters mixed with warm aerated surface waters, forming regional dysoxia, so that extreme carbonate supersaturation and dysoxic conditions were both required for their growth. Long-term oceanic and atmospheric changes may have contributed to a trigger for ETM formation. In equatorial western Pangea, the earliest microbialites are late Early Triassic, but it is possible that ETMs could exist in western Pangea, if well-preserved earliest Triassic facies are discovered in future work

Geobiology of the late Paleoproterozoic Duck Creek Formation, Western Australia

The ca. 1.8 Ga Duck Creek Formation, Western Australia, preserves 1000 m of carbonates and minor iron formation that accumulated along a late Paleoproterozoic ocean margin. Two upward-deepening stratigraphic packages are preserved, each characterized by peritidal precipitates at the base and iron formation and carbonate turbidites in its upper part. Consistent with recent studies of Neoarchean basins, carbon isotope ratios of Duck Creek carbonates show no evidence for a strong isotopic depth gradient, but carbonate minerals in iron formations can be markedly depleted in C-13. In contrast, oxygen isotopes covary strongly with depth; delta O-18 values as positive as 2%. VPDB in peritidal facies systematically decline to values of 6 to 16% in basinal rocks, reflecting, we posit, the timing of diagenetic closure. The Duck Creek Formation contains microfossils similar to those of the Gunflint Formation, Canada; they are restricted to early diagenetic cherts developed in basinal facies, strengthening the hypothesis that such fossils capture communities driven by iron metabolism. Indeed, X-ray diffraction data indicate that the Duck Creek basin was ferruginous throughout its history. The persistence of ferruginous waters and iron formation deposition in Western Australia for at least several tens of millions of years after the transition to sulfidic conditions in Laurentia suggests that the late Paleoproterozoic expansion of sulfidic subsurface waters was globally asynchronous

Sudden changes in fluvial style across the Permian / Triassic boundary in the eastern Iberian Ranges, Spain: Analysis of possible causes

The sedimentary record of the Late Permian and Early Triassic of the eastern Iberian Ranges shows four major, sudden, or very rapid, vertical changes in fluvial style. The Late Permian sedimentary cycle starts with the Boniches Formation, of alluvial fan-braided fluvial origin, which grades vertically over within a few metres into the Alcotas Formation, deposited by low to high sinuosity, avulsion-prone rivers with extensive floodplains. The Alcotas Formation contains calcimorphic soils, plant remains and pollen and spore assemblages. However, the upper third of the unit is devoid of all organic remains and soils and is characterized by a dominant red colour, the sandstone levels were deposited by high-sinuosity, meandering rivers. This major change took place during the Late Permian and is probably coeval with the emplacement of the Emeishan basaltic Large Igneous Province (LIP) in SE China. Rocks of the Boniches and Alcotas Formations are separated by an angular unconformity from the overlying strata, which consist of the Late Permian conglomeratic Hoz del Gallo Formation, of alluvial fan–gravel braided fluvial origin and the sandy Cañizar Formation, of low-sinuosity sandy river origin. The Permian– Triassic boundary lies, probably between the upper part of the Hoz del Gallo Formation and the first metres of the Cañizar Formation. Late Permian pollen and spore assemblages have been found in the Hoz del Gallo Formation but the Cañizar Formation is barren, with the exception of an Anisian (Middle Triassic) assemblage at the top. Tectonic extensional pulses in the Iberian Basin caused the changes observed between the lower and upper parts of the Boniches Formation, at the base of the Hoz del Gallo Formation and between the lower and upper part of this Formation. The changes observed in the uppermost part of the Alcotas Formation are not easily explained by tectonic causes, nor those in the passage from the Hoz del Gallo Formation to the Cañizar Formation. Similar sedimentary characteristics of the sandy Cañizar Formation such as amalgamated sandstone bodies, erosion and reactivation surfaces, dominant trough cross-stratification, tabular geometry, absence of plant remains and pollen and spores, and absence of silts and clays to those of coeval formations in places as far away as Australia, South Africa and Brazil suggest a global rather than local cause for these abrupt changes in fluvial style. This global cause was probably die-off of plant cover over extensive areas of the catchment, related to the end of the Permian mass extinction and possibly related to the emplacement of the West Siberian basaltic Large Igneous Province (LIP), responsible for drastic atmospheric and marine changes

Audience-Pleasing Physical Models to Support CO2 Outreach

Outreach to increase public understanding is critical to implementation of carbon capture and storage, but conventional lectures may fail to engage a non-technical audience. In this presentation we will exhibit a selection of do-it-yourself demonstrations that are proven to grab an audience’s attention and can be adapted for use with a variety of groups. Using interesting and engaging physical models, and without use of PowerPoint, posters or handouts, speakers can show a non-technical audience (1) how CO2 is formed from the combustion of hydrocarbon molecules(2) how much CO2 we produce in daily activities, (3) why CO2 works to trap heat in the atmosphere 4)the properties of CO2 and its health and safety risks (5)how geologic storage of CO2 would work to reduce emissions. These demonstrations require only readily available, low-cost materials and have been used successfully with a variety of audiences, from adults to elementary school-age children. They are simple enough to be replicated by audience members for use in school and community programs.Bureau of Economic Geolog