The co-evolution of phytoplankton and trace element cycles in the oceans.

abstract：:The period 800-717 million years (Ma) ago, in the lead-up to the Sturtian Snowball glaciation, saw an increase in the diversity of eukaryotic microfossils. To afford an independent and complementary view of this evolutionary period, this study presents the distribution of eukaryotic biomarkers from three pre-Sturtian ...

journal_title：Geobiology

authors： Brocks JJ,Jarrett AJ,Sirantoine E,Kenig F,Moczydłowska M,Porter S,Hope J

更新日期：2016-03-01 00:00:00

abstract：:Nitrogen forms an integral part of the main building blocks of life, including DNA, RNA, and proteins. N2 is the dominant gas in Earth's atmosphere, and nitrogen is stored in all of Earth's geological reservoirs, including the crust, the mantle, and the core. As such, nitrogen geochemistry is fundamental to the evolut...

journal_title：Geobiology

authors： Zerkle AL,Mikhail S

更新日期：2017-05-01 00:00:00

abstract：:Reworked and fluidized fine-grained deposits in energetic settings are a major modern-day feature of river deltas and estuaries. Similar environments were probably settings for microbial evolution on the early Earth. These sedimentary systems act as efficient biogeochemical reactors with high bacterial phylogenetic di...

journal_title：Geobiology

authors： Aller JY,Aller RC,Kemp PF,Chistoserdov AY,Madrid VM

更新日期：2010-06-01 00:00:00

abstract：:Permanently anoxic regions in the ocean are widespread and exhibit unique microbial metabolic activity exerting substantial influence on global elemental cycles and climate. Reconstructing microbial metabolic activity rates in these regions has been challenging, due to the technical difficulty of direct rate measureme...

journal_title：Geobiology

authors： Louca S,Astor YM,Doebeli M,Taylor GT,Scranton MI

更新日期：2019-11-01 00:00:00

abstract：:In modern microbial mats, hydrogen sulfide shows pronounced sulfur isotope (δ34 S) variability over small spatial scales (~50‰ over <4 mm), providing information about microbial sulfur cycling within different ecological niches in the mat. In the geological record, the location of pyrite formation, overprinting from m...

journal_title：Geobiology

authors： Gomes ML,Fike DA,Bergmann KD,Jones C,Knoll AH

更新日期：2018-01-01 00:00:00

abstract：:The formation of carbonate concretions is a cementation process which passively infills the pore spaces within sediments. They record the original environments of deposition and diagenetic conditions of the host rocks. Little is known about the precise mechanisms responsible for the precipitation of carbonate concreti...

journal_title：Geobiology

authors： Wei H,Tang Z,Qiu Z,Yan D,Bai M

更新日期：2020-01-01 00:00:00

abstract：:Stromatolites are one of the oldest and most intriguing organosedimentary deposits. In contrast to stromatolites of the Precambrian to Early Ordovician, Phanerozoic equivalents occurred episodically under specific conditions. A group of previously undescribed stromatolites in composition occur in the Lower Triassic (O...

journal_title：Geobiology

authors： Ezaki Y,Liu JB,Adachi N

更新日期：2012-01-01 00:00:00

abstract：:Although nitrogen is a key element in organic molecules such as nucleic acids and proteins, the timing of the emergence of its modern biogeochemical cycle is poorly known. Recent studies on the antiquity of the nitrogen cycle and its interaction with free oxygen suggests the establishment of a complete aerobic N bioge...

journal_title：Geobiology

authors： Thomazo C,Ader M,Philippot P

更新日期：2011-03-01 00:00:00

abstract：:Biogeochemical changes in marine sediments during coastal water hypoxia are well described, but less is known about underlying changes in microbial communities. Bacterial and archaeal communities in Louisiana continental shelf (LCS) hypoxic zone sediments were characterized by pyrosequencing 16S rRNA V4-region gene fr...

journal_title：Geobiology

authors： Devereux R,Mosher JJ,Vishnivetskaya TA,Brown SD,Beddick DL Jr,Yates DF,Palumbo AV

更新日期：2015-09-01 00:00:00

abstract：:Meromictic lakes with anoxic bottom waters often have active methane cycles whereby methane is generally produced biogenically under anoxic conditions and oxidized in oxic surface waters prior to reaching the atmosphere. Lakes that contain dissolved ferrous iron in their deep waters (i.e., ferruginous) are rare, but v...

journal_title：Geobiology

authors： Lambrecht N,Katsev S,Wittkop C,Hall SJ,Sheik CS,Picard A,Fakhraee M,Swanner ED

更新日期：2020-01-01 00:00:00

abstract：:Mixing of sediments by moving animals becomes apparent in the trace fossil record from about 550 million years ago (Ma), loosely overlapping with the tail end of the extreme carbonate carbon isotope δ13 Ccarbonate fluctuations that qualitatively distinguish the Proterozoic geochemical record from that of the Phanerozo...

journal_title：Geobiology

authors： Boyle RA,Dahl TW,Bjerrum CJ,Canfield DE

更新日期：2018-05-01 00:00:00

abstract：:The emplacement of subaqueous gravity-driven sediment flows imposes a significant physical and geochemical impact on underlying sediment and microbial communities. Although previous studies have established lasting mineralogical and biological signatures of turbidite deposition, the response of bacteria and archaea wi...

journal_title：Geobiology

authors： Harrison BK,Myrbo A,Flood BE,Bailey JV

更新日期：2018-03-01 00:00:00

abstract：:Previous studies of the subsurface biosphere have deduced average cellular doubling times of hundreds to thousands of years based upon geochemical models. We have directly constrained the in situ average cellular protein turnover or doubling times for metabolically active micro-organisms based on cellular amino acid a...

journal_title：Geobiology

authors： Onstott TC,Magnabosco C,Aubrey AD,Burton AS,Dworkin JP,Elsila JE,Grunsfeld S,Cao BH,Hein JE,Glavin DP,Kieft TL,Silver BJ,Phelps TJ,van Heerden E,Opperman DJ,Bada JL

更新日期：2014-01-01 00:00:00

abstract：:The well-known debate on the nature and origin of intracellular inclusions (ICIs) in silicified microfossils from the early Neoproterozoic Bitter Springs Formation has recently been revived by reports of possible fossilized nuclei in phosphatized animal embryo-like fossils from the Ediacaran Doushantuo Formation of So...

journal_title：Geobiology

authors： Pang K,Tang Q,Schiffbauer JD,Yao J,Yuan X,Wan B,Chen L,Ou Z,Xiao S

更新日期：2013-11-01 00:00:00

abstract：:Organic biomarkers in marine sedimentary rocks hold important clues about the early history of Earth's surface environment. The chemical relicts of carotenoids from anoxygenic sulfur bacteria are of particular interest to geoscientists because of their potential to signal episodes of marine photic-zone euxinia such as...

journal_title：Geobiology

authors： Meyer KM,Macalady JL,Fulton JM,Kump LR,Schaperdoth I,Freeman KH

更新日期：2011-07-01 00:00:00

abstract：:Ediacaran sediments record an unusual global carbon cycle perturbation that has been linked to widespread oceanic oxygenation, the Shuram negative C isotope excursion (NCIE). However, proxy-based estimates of global ocean redox conditions during this event have been limited largely due to proxy specificity (e.g., euxi...

journal_title：Geobiology

authors： Fan H,Nielsen SG,Owens JD,Auro M,Shu Y,Hardisty DS,Horner TJ,Bowman CN,Young SA,Wen H

更新日期：2020-05-01 00:00:00

abstract：:The later Cambrian Steptoean Positive Carbon Isotope Excursion (SPICE) event was an episode marked by pronounced changes to the global biogeochemical cycles of carbon and sulfur and significant extinctions on several paleocontinents including Laurentia (North America). While the exact cause(s) of these events remains ...

journal_title：Geobiology

authors： LeRoy MA,Gill BC

更新日期：2019-07-01 00:00:00

abstract：:The ability of micro-organisms to oxidize manganese (Mn) from Mn(II) to Mn(III/IV) oxides transcends boundaries of biological clade or domain. Many bacteria and fungi oxidize Mn(II) to Mn(III/IV) oxides directly through enzymatic activity or indirectly through the production of reactive oxygen species. Here, we determ...

journal_title：Geobiology

authors： Sutherland KM,Wankel SD,Hansel CM

更新日期：2018-07-01 00:00:00

abstract：:Alvinellid polychaete worms form multilayered organic tubes in the hottest and most rapidly growing areas of deep-sea hydrothermal vent chimneys. Over short periods of time, these tubes can become entirely mineralized within this environment. Documenting the nature of this process in terms of the stages of mineralizat...

journal_title：Geobiology

authors： Georgieva MN,Little CT,Ball AD,Glover AG

更新日期：2015-03-01 00:00:00

abstract：:The lower Cambrian grainy phosphorites of the northern Montagne Noire occur interbedded with grey to black, laminated to massive shales and limestones deposited along the edge of a continental shelf, associated with slope-related facies and unstable substrates. The concentration of phosphate took place by repeated alt...

journal_title：Geobiology

authors： Alvaro JJ,Clausen S

更新日期：2010-03-01 00:00:00

abstract：:Microbial fossils and textures are commonly preserved in Ediacaran and early Cambrian coarse-grained siliciclastic sediments that were deposited in tidal and intertidal marine settings. In contrast, the fossilization of micro-organisms in similar marine environments of post-Cambrian age is less frequently reported. Th...

journal_title：Geobiology

authors： Newman SA,Klepac-Ceraj V,Mariotti G,Pruss SB,Watson N,Bosak T

更新日期：2017-07-01 00:00:00

abstract：:New experimental results of fluid-mineral reactions at hydrothermal conditions relevant to life demonstrate that key redox reactions involving iron, sulfur, and hydrogen remain at disequilibrium at 100 °C, even in a heterogeneous system and thus are energetically favorable for microbial metabolism. Predictions from ge...

journal_title：Geobiology

authors： Houghton JL,Seyfried WE Jr

更新日期：2010-12-01 00:00:00

abstract：:The ca. 1.9 Ga Beaverlodge Lake paleosol was studied using redox-sensitive Cr isotopes in order to determine the isotopic response to paleoweathering of a rhyodacite parent rock 500 million years after the Great Oxidation Event. Redox reactions occurring in modern weathering environments produce Cr(VI) that is enriche...

journal_title：Geobiology

authors： Toma J,Holmden C,Shakotko P,Pan Y,Ootes L

更新日期：2019-09-01 00:00:00

abstract：:Microfossils belonging to the 1.88-billion-year-old 'Gunflint-biota' are preserved as carbonaceous and hematitic filaments and spheres that are believed to represent ancient chemolithoautotrophic Fe(II) oxidizing bacteria that grew above a chemocline where ferruginous seawater upwelled into shallow, oxygenated waters....

journal_title：Geobiology

authors： Shapiro RS,Konhauser KO

更新日期：2015-05-01 00:00:00

abstract：:Zodletone spring in Oklahoma is a unique environment with high concentrations of dissolved-sulfide (10 mm) and short-chain gaseous alkanes, exhibiting characteristics that are reminiscent of conditions that are thought to have existed in Earth's history, in particular the late Archean and early-to-mid Proterozoic. Her...

journal_title：Geobiology

authors： Bühring SI,Sievert SM,Jonkers HM,Ertefai T,Elshahed MS,Krumholz LR,Hinrichs KU

更新日期：2011-03-01 00:00:00

abstract：:Subseafloor sulfate concentrations typically decrease with depth as this electron acceptor is consumed by respiring microorganisms. However, studies show that seawater can flow through hydraulically conductive basalt to deliver sulfate upwards into deeply buried overlying sediments. Our previous work on IODP Site C001...

journal_title：Geobiology

authors： Cox TL,Gan HM,Moreau JW

更新日期：2019-03-01 00:00:00

abstract：:Metal sulfide minerals, including mercury sulfides (HgS), are widespread in hydrothermal vent systems where sulfur-oxidizing microbes are prevalent. Questions remain as to the impact of mineral composition and structure on sulfur-oxidizing microbial populations at deep-sea hydrothermal vents, including the possible ro...

journal_title：Geobiology

authors： Wang CH,Gulmann LK,Zhang T,Farfan GA,Hansel CM,Sievert SM

更新日期：2020-09-01 00:00:00

abstract：:The Strelley Pool Formation (SPF) is widely distributed in the East Pilbara Terrane (EPT) of the Pilbara Craton, Western Australia, and represents a Paleoarchean shallow-water to subaerial environment. It was deposited ~3.4 billion years ago and displays well-documented carbonate stromatolites. Diverse putative microf...

journal_title：Geobiology

authors： Sugitani K,Mimura K,Takeuchi M,Lepot K,Ito S,Javaux EJ

更新日期：2015-11-01 00:00:00

abstract：:We here show that nano-scale mapping of elements commonly utilized in biological cycles provides a promising new additional line of evidence when evaluating the extent of the contribution of biology to microbialites. Our case study comes from Lake Clifton in Western Australia, a unique environment where living domical...

journal_title：Geobiology

authors： Wacey D,Gleeson D,Kilburn MR

更新日期：2010-12-01 00:00:00

abstract：:Ocean acidification by atmospheric carbon dioxide has increased almost continuously since the last glacial maximum (LGM), 21,000 years ago. It is expected to impair tropical reef development, but effects on reefs at the present day and in the recent past have proved difficult to evaluate. We present evidence that acid...

journal_title：Geobiology

authors： Riding R,Liang L,Braga JC

更新日期：2014-09-01 00:00:00