In this study, petrographic and geochemical data are presented on extremely fresh komatiites from the Weltevreden Formation, Barberton Greenstone Belt.
NASA Astrophysics Data System (ADS)
In the Barberton greenstone belt, four specific spherule horizons, named S1 to S4, have been proposed as being of inpact origin.
The Jamestown Ophiolite Complex of the Barberton greenstone belt, South Africa, is investigated, and
NASA Technical Reports Server (NTRS)
Nov 23, 2008 ... Ironstone pods in the Archean Barberton greenstone belt, South Africa: Earth's oldest seafloor hydrothermal vents reinterpreted as Quaternary ...
NASA Website
The relationship between early Archean greenstones and high grade gneisses in the Ancient Gneiss Complex of Swaziland and the neighboring Barberton greenstone belt in Southern Africa is discussed. New high precision zircon analyses reveal a complex histor...
National Technical Information Service (NTIS)
in the Barberton Greenstone Belt, South Africa. Chromium iso- topes have conclusively shown that at least one of these con- tains -20% meteoritic material ...
3.22 Ga, in the Barberton Greenstone Belt, South Africa: Keys to the role of large impacts on the evolution of the early Earth. Proceedings of the 10th Rubey ...
Geological field trip to the Barberton Greenstone Belt, South Africa. Name. Jasper and iron-formations associated with the 1.74-Ga Jerome volcanic massive ...
Sep 13, 2011 ... Petrology and Sedimentology of Mid-Archean Impact-Producted Spherule Beds, Barberton Greenstone Belt, South Africa [Abstract]. ...
Sep 5, 2011 ... Spherule beds 3.47-3.24 billion years old in the Barberton Greenstone Belt, South Africa: A record of large meteorite impacts and their ...
Sulfur isotope evidence for the origin of 3.4 to 3.1 Ga pyrite at the Princeton gold mine, Barberton Greenstone Belt, South Africa. ...
Environment and early life in the early Archaean Barberton Greenstone Belt, South Africa [Abstract]. First Astrobiology Science Conference, ...
and Fig Tree Groups, Barberton Greenstone belt, South Africa, and Warrawoona Group, eastern. Pilbara Block, Western Australia, contain an abundant record of ...
XRF and laser Raman analysis of chemical and potential microbial-mat sediments from the Barberton greenstone belt, South Africa.
The size distribution and relative abundance of the five major types of spherules in the S3 section of the Barberton greenstone belt, South Africa are analyzed and quantified.
Beds of sand-sized spherules in the 3400-million-year-old Fig Tree Group, Barberton Greenstone belt,
Petrology and Sedimentology of Mid-Archean Impact-Producted Spherule Beds, Barberton Greenstone Belt, South Africa [Abstract]. SEPM Research Conference. ...
Benjamin Black Stanford University Examining the Evidence for Early Life and Environments in the Barberton Greenstone Belt, South Africa. Barbara Cavalazzi ...
Aug 7, 2011 ... Compositional grading in an impact-produced spherule bed, Barberton Greenstone Belt, South Africa: A key to condensation history of rock ...
hyaloclastites from the Barberton Greenstone Belt, South Africa. Earth Planet. Sci. Lett. 241, 707-722 (2006). 27. Corliss, J. B. et al. An hypothesis concerning ...
Spherule Beds 3.47-3.24 Billion Years Old in the Barberton Greenstone Belt, South Africa: A Record of Large Meteorite Impacts and Their Influence on Early ...
The Barberton Greenstone belt is a 3.5- to 3.2-Ga-old formation situated in the Swaziland Supergroup
Zircons from three spherule-bearing impact ejecta layers from Barberton, South Africa, were investigated for the presence of impact shock microstructures.
This study examines the vertical compositional variability in a single early Archean spherule bed in the Barberton Greenstone Belt, South Africa in order to better identify the process by which impact vapor clouds condense and spherules form and accumulate.
The Barberton Greenstone belt is a 3.5- to 3.2-Ga-old formation situated in the Swaziland Supergroup near Barberton, northeast Transvaal, South Africa. The belt includes a lower, predominantly volcanic sequence, and an upper sedimentary sequence (e.g., th...
.R., 1996. 3.07�2.97 Ga Greenstone belt formation in the northeastern Kaapvaal Craton: implications and greenstone belts of the older east- ern KC is truncated by the N�S tectonic grain of the younger western Barberton Greenstone Belt, are flanked ...
E-print Network
Sequences in the Barberton Mountain Land greenstone belt (southern Africa) were examined to determine the nature of the sedimentary rocks, their tectonic implications, and their bearing on the present large-scale structural condition of the belt. Also ass...
The search for extraterrestrial life and especially martian life hinges on a variety of methods used
shallow-water sediment, Barberton greenstone belt, South Africa. Precambrian Research, 106, 93-114. Westall, F., Steele, A., Toporski, J., Walsh, M., Allen, ...
Jun 30, 2011 ... Field work was conducted in the 3.5-3.2 Ga Barberton greenstone belt, South Africa for three weeks, July 2004. ...
Walsh, M. and Lowe, D.R. 1999, In: Geological evolution of the Barberton Greenstone Belt (Lowe, D. R. & Byerly, G. R., Eds.), Geological Society of America, ...
Characteristics, origin, and implications of Archean impact-produced spherule beds, 3.47-3.22 Ga, in the Barberton Greenstone Belt, South Africa: Keys to ...
... of synsedimentary to very early diagenetic cherts are widely preserved in the 3.5-3.2 Ga Swaziland Supergroup, Barberton greenstone belt, South Africa. ...
2 days ago ... Pyroclastic komatiitic eruptions in the 3.5-3.2 Ga Barberton Greenstone Belt, South Africa. Geological Association of Canada, Montreal Meeting. ...
We present evidence for three new major impacts from our geologic studies of the 3.55 to 3.25 Ga Barberton greenstone belt, increasing the number of major impacts to seven.
... 3.47-3.22 Ga, in the Barberton Greenstone Belt, South Africa: Keys to the ..... Thi, W.F., van Dishoeck, E.F., Blake, G.A., van Zadelhoff, G.J., Horn, ...
The thick-bedded, competent quartzose sandstones, conglomerates, and siltstones of the Moodies Group (<3,225 Ma) influence structural style in the ~3.1-3.5 Ga Barberton Greenstone Belt. Moodies Group rocks are folded into a train of tight, subparallel, doubly plunging, overtuned synclines separated by narrow, strike-parallel fault ...
Although many people have written about hydrothermal systems in the early Earth, little real evidence is available. New data from the Barberton greenstone belt (South Africa) and greenstone belts of the East Pilbara (Western Australia), provide proof of the existence and nature of hydrothermal ...
Raman spectra of carbonaceous material were collected in situ from samples of cherts of the Onverwacht and Fig Tree Groups in the central Barberton greenstone belt. The spectra feature two dominant peaks characteristic of disordered carbon: the D peak at �1310 cm-1 and the O peak at 1580 1600 cm-1. D peak positions and relative peak ...
Sm-Nd isotopic data from carbonate-derived clay minerals of the 3.22-3.25 Ga Fig Tree Group, Barberton greenstone belt, South Africa, form a linear array corresponding to an age of 3102 +/- 64 Ma, making these minerals the oldest dated clays on Earth. The obtained age is 120-160 m.y. younger than the depositional age determined by ...
PubMed
Sm-Nd isotopic data from carbonate-derived clay minerals of the 3.22-3.25 Ga Fig Tree Group, Barberton greenstone belt, South Africa, form a linear array corresponding to an age of 3102 �64 Ma, making these minerals the oldest dated clays on Earth. The obtained age is 120-160 m.y. younger than the depositional age determined by ...
The paucity of komatiitic pyroclastic rocks in Archean greenstonesequences is commonly interpreted to reflect the low volatilecontents of komatiitic liquids and the mechanical difficultiesin explosively erupting highly fluid ultramaficmagmas. Herewe report the presence of multiple layers of ultramafic pyroclasticdebris in 3481-3243 Ma rocks of the Onverwacht Group inthe ...
Laser ablation mass spectroscopy analyses of sulfur isotopic compositions of microscopic-sized grains of pyrite that formed about 3.4 billion years ago in the Barberton Greenstone Belt, South Africa, show that the pyrite formed by bacterial reduction of seawater sulfate. These data imply that by about 3.4 billion years ago ...
Laser ablation mass spectroscopy analysis of sulfur isotopic compositions of microscopic-sized grains of pyrite that formed about 3.4 billion years ago in the Barberton Greenstone Belt, South Africa, show that the pyrite formed by bacterial reduction of seawater sulfate. These data imply that by about 3.4 billion years ago ...
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