3230–3200 Ma post-orogenic extension and mid-crustal magmatism along the southeastern margin of the Barberton Greenstone Belt, South Africa

Lana, Cristiano; Buick, Ian S.; Stevens, Gary; Rossouw, Riana; Wet, Willem de

doi:10.1016/j.jsg.2011.03.007

Cited by 37 publications

(29 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The sulphide reefs consist of disseminated to massive sulphides, situated at concordant and discordant structures in the greywackes and shales. Fractures in these rocks were formed due to the tangential shears, which initiated during the major folding events Lana et al, 2010;Lana et al, 2011). The sulphide reefs range from 2 cm up to 2 m in width, and extend approximately 500 m along strike Dziggel et al, 2007).…”

Section: Fairview Minementioning

confidence: 99%

Geochemical identification of episodes of gold mineralisation in the Barberton Greenstone Belt, South Africa

Altigani

Merkle

Dixon

2016

Ore Geology Reviews

View full text Add to dashboard Cite

The morphology and mineral chemistry of gold and associated sulphides at Sheba, Fairview, and New Consort gold mines in the Barberton Greenstone Belt (BGB) identify two main types of mineralization. The first type occurs associated with sulphides (mainly pyrite), either as inclusions (10-30 µm) or as sub-microscopic gold. The second gold type consists of large gold grains (≥ 100µm) within the silicates (mostly quartz).LA-ICP-MS studies reveal that some gold and associated sulphide grains contain high values of Cl, Br, Na, and I.The elemental relationships reflect the different chemistry and precipitation processes of possible source fluids, and identify several episodes of mineralisation in the study area, one of them formed due to a boiling process in a supercritical hydrothermal environment. This paper reports on the compositional characteristics of these gold grains, the significance of the halogen contents, and the implications for possible sources of the gold and associated sulphides.

show abstract

Section: Fairview Minementioning

confidence: 99%

Geochemical identification of episodes of gold mineralisation in the Barberton Greenstone Belt, South Africa

Altigani

Merkle

Dixon

2016

Ore Geology Reviews

View full text Add to dashboard Cite

show abstract

“…3.50-3.45 Ga Stolzburg block to the south of the belt (e.g., Kisters et al, 2010;Lana et al, 2010b); and (3) accretion of the ca. 3.66 Ga Ancient Gneiss Complex terrane to the southeast of the greenstone belt along the Phophonyane shear zone system (e.g., Schoene et al, 2008;Lana et al, 2011) (Fig. 1).…”

Section: Introductionmentioning

confidence: 99%

“…1; Schoene et al, 2008;Schoene and Bowring, 2010;Lana et al, 2010a), which consolidated and increased the strength and preservation potential of the newly accreted terranes (e.g., Schoene et al, 2008). This was accompanied by continued NW-SE regional shortening (Barberton greenstone belt D 3 ; De Ronde and de Wit, 1994;Westraat et al, 2005;Belcher and Kisters, 2006a), and concomitant NE-SW transtensional tectonism, resulting in the diachronous and differential orogen-parallel exhumation and cooling of the various crustal blocks along all margins of the Barberton greenstone belt and Ancient Gneiss Complex between 3.23 and 3.10 Ga (De Ronde and de Wit, 1994;Kisters et al, 2003;Schoene and Bowring, 2007;Schoene et al, 2008;Lana et al, 2010bLana et al, , 2011.…”

Section: Introductionmentioning

confidence: 99%

Successive midcrustal, high-grade metamorphic events provide insight into Mid-Archean mountain-building along the SE margin of the proto-Kaapvaal craton

Taylor¹,

Stevens²,

Buick³

et al. 2012

Geological Society of America Bulletin

View full text Add to dashboard Cite

“…The standard and unknown zircon grains were ablated in a small-volume (tear-drop shape) sample cell with an insert that holds one 25-mm-diameter sample mount and a 7-mm-diameter standard mount . The acquisitions consisted of a 20 s of laser warm-up and a measurement of the gas blank, followed by 40 s measurements of the U, Th and Pb signals during ablation, and a 20 s washout (e.g., Buick et al, 2011;Lana et al, 2011). The samples, the standards and the sample holders were acid-washed before being analyzed to remove possible surface Pb contamination.…”

Section: Methodsmentioning

confidence: 99%

Constraints on the Statherian evolution of the intraplate rifting in a Paleo-Mesoproterozoic paleocontinent: New stratigraphic and geochronology record from the eastern São Francisco craton

et al. 2015

View full text Add to dashboard Cite

An integrated approach of stratigraphic analysis and U-Pb age dating reveals some information on the tectonosedimentary evolution of the Statherian cover of the São Francisco craton in the so-called Espinhaço basin (Atlantic shield in eastern Brazil). Here, continental sedimentation patterns, such as alluvial fan, braided-plain and lacustrine facies associations, with associated volcanic rocks are documented in two superposed basin fill-successions, which are defined as the Algodão and Sapiranga Synthems and grouped in the Botuporã Supersynthem. Both studied units consist mainly of conglomerates and cross-bedded sandstones and minor amounts of mudstones, sedimentary breccias, volcanic lava beds and volcaniclastic rocks, which were deposited in a rift basin -the Botuporã rift -during two syn-rifting phases. The Algodão Synthem represents the first rifting phase. The basal synsedimentary conglomerates of this unit were deposited mainly by subaerial debris flows, most likely along and near a rift border fault. The framework of this rock consists of only crystalline rock clasts from the basement and no fragments of volcanic rocks. Detrital zircon grains that were extracted from this facies show ages older than 2.05 Ga. The remainder of the section is dominated by fluvial sandy lithofacies with minor conglomerate lenses and sandstone-mudstone heterolithic lithofacies, which represent distal, waning-flood deposits in a lacustrine environment. The upper section also contains hummocky cross-stratified sandstone lithofacies, which are related to a storm-influenced deposition. On top of the Algodão succession, the volcanic rocks were dated at 1775 ± 7 Ma, which was interpreted as the near final age of the first rift-phase. Representing the second rift-phase, the Sapiranga Synthem shows similar sedimentation patterns to the Algodão Synthem. The Sapiranga Synthem rests directly on the volcanic rocks of the Algodão Synthem, and its basal conglomerates (which are most likely also related to a master fault) contain voluminous clasts of volcanic rocks, sandstones and crystalline rocks. The detrital zircon grains that were extracted from this facies show ages of 1741 ± 14 and 1766 Ma as well older than 2.05 Ga. The volcanic rocks on the upper succession of the Sapiranga Synthem record ages of 1740 ± 10 Ma, which finalized the Botuporã rift evolution. A preliminary geochemical study of volcanic rocks from the Botuporã Supersynthem showed that these rocks are alkaline rocks with high K 2 O/Na 2 O ratios, which belong to an ultrapotassic suite. The low concentrations of MgO wt.% suggest a felsic ultrapotassic character. The Botuporã Supersynthem is unconformably covered by a volcanosedimentary rift-succession of EoCalymmian age -the Pajeú Synthem, which represents the second rifting stage of the Espinhaço basin. Several Statherian-related volcano-sedimentary sequences and anorogenic granitoids occur dispersed in the São Francisco block, which requires a regional geologic model to explain the extensional and magmatism process during ...

show abstract

3230–3200 Ma post-orogenic extension and mid-crustal magmatism along the southeastern margin of the Barberton Greenstone Belt, South Africa

Cited by 37 publications

References 40 publications

Geochemical identification of episodes of gold mineralisation in the Barberton Greenstone Belt, South Africa

Geochemical identification of episodes of gold mineralisation in the Barberton Greenstone Belt, South Africa

Successive midcrustal, high-grade metamorphic events provide insight into Mid-Archean mountain-building along the SE margin of the proto-Kaapvaal craton

Constraints on the Statherian evolution of the intraplate rifting in a Paleo-Mesoproterozoic paleocontinent: New stratigraphic and geochronology record from the eastern São Francisco craton

Contact Info

Product

Resources

About