Geochronology of a Late Archaean flood basalt province in the Pilbara Craton, Australia: constraints on basin evolution, volcanic and sedimentary accumulation, and continental drift rates

Blake, Tim S.; Buick, Roger; Brown, Suzanne M.; Barley, Mark

doi:10.1016/j.precamres.2004.03.012

Cited by 112 publications

(52 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Briefly, the upper Carawine Dolomite with abundant stromatolites is well recognized as a shelf deposit having platform architecture (11). The Tumbiana very shallow carbonate environment flanked a large, southerly subsiding rift basin (12), and it received a high flux of terrestrial detritus. The Tumbiana Formation has been interpreted as a f luviallacustrine deposit (13) (but others suggest that it may also contain shallow marine deposits; see ref.…”

Section: Resultsmentioning

confidence: 99%

Late Archean rise of aerobic microbial ecosystems

Eigenbrode

Freeman

2006

Proc. Natl. Acad. Sci. U.S.A.

223

162

View full text Add to dashboard Cite

We report the 13 C content of preserved organic carbon for a 150 million-year section of late Archean shallow and deepwater sediments of the Hamersley Province in Western Australia. We find a 13 C enrichment of Ϸ10‰ in organic carbon of post-2.7-billion-yearold shallow-water carbonate rocks relative to deepwater sediments. The shallow-water organic-carbon 13 C content has a 29‰ range in values (؊57 to ؊28‰), and it contrasts with the less variable but strongly 13 C-depleted (؊40 to ؊45‰) organic carbon in deepwater sediments. The 13 C enrichment likely represents microbial habitats not as strongly influenced by assimilation of methane or other 13 C-depleted substrates. We propose that continued oxidation of shallow settings favored the expansion of aerobic ecosystems and respiring organisms, and, as a result, isotopic signatures of preserved organic carbon in shallow settings approached that of photosynthetic biomass. Facies analysis of published carbon-isotopic records indicates that the Hamersley shallow-water signal may be representative of a late Archean global signature and that it preceded a similar, but delayed, 13 C enrichment of deepwater deposits. The data suggest that a globalscale expansion of oxygenated habitats accompanied the progression away from anaerobic ecosystems toward respiring microbial communities fueled by oxygenic photosynthesis before the oxygenation of the atmosphere after 2.45 billion years ago.organic carbon ͉ isotopes ͉ methanotrophy ͉ oxygen

show abstract

Section: Resultsmentioning

confidence: 99%

Late Archean rise of aerobic microbial ecosystems

Eigenbrode

Freeman

2006

Proc. Natl. Acad. Sci. U.S.A.

223

162

View full text Add to dashboard Cite

show abstract

“…The Nullagine and Mount Jope Supersequences have recently been dated with high precision (Fig. 1, Wingate, 1999;Blake et al, 2004). The succession is generally only gently folded and the metamorphic grade does not exceed 200 MPa and 300…”

Section: Geology and Samplingmentioning

confidence: 99%

“…For this study, we selected flood basalt specimens from Package 1 (GSP61-63, 65, and 66); felsic porphyry samples from Package 2 (GSP91); and flood basalt samples from Package 7 (GSP77-79). Published ages of these packages made using the SHRIMP U-Pb and Pb-Pb methods (Wingate, 1999;Blake et al, 2004) range from 2772±2 Ma (Package 1) to 2721±4 Ma (Package 7).…”

Section: Geology and Samplingmentioning

confidence: 99%

See 1 more Smart Citation

The intensity of the geomagnetic field in the late-Archaean: new measurements and an analysis of the updated IAGA palaeointensity database

2009

View full text Add to dashboard Cite

We firstly present the results of a detailed palaeointensity study performed on 54 samples from 9 volcanic units of late Archaean age (2724-2772 Ma) from the Pilbara Craton, Western Australia. These results were severely affected by magnetomineralogical alteration occurring during the laboratory heating process necessitating the application of a correction procedure. The correction allowed results from three lavas to pass strict selection criteria but we deem that only one of these exhibits sufficient internal consistency to be considered moderately reliable. It yields a virtual dipole moment of 47±6 ZAm 2 which is 60% of the present-day value. We combine this determination with a filtered dataset from the updated IAGA (International Association of Geomagnetism and Aeronomy) palaeointensity database, PINT08. Directional secular variation has recently been shown to have changed fundamentally since the Archaean, probably as a consequence of inner core growth since that time. However, here we argue that it is still unclear whether this evolution was accompanied by a single long timescale change in average poloidal field intensity. While the distribution of Precambrian palaeointensity determinations as a whole is significantly lower than that for the last 300 Myr, we show that this finding largely reflects data from the Proterozoic aeon. The distribution of more ancient measurements from the late Archaean-earliest Proterozoic is indistinguishable from that of the last 300 Myr which might suggest that a 'Proterozoic dipole low' period existed between two periods of higher field intensity. Were this pattern of long-term geomagnetic intensity variation to be supported by the addition of new data in the future, then it could indicate a related three-stage evolution in core dynamics, namely: vigorous thermal convection caused by high core-mantle heat flux early in the Earth's history, weaker thermal convection later as the heat flux fell, and finally, strong compositional convection since the inner core nucleated.

show abstract

“…For example, Blake et al (2004) obtained precise radiometric ages on strata in the eastern Pilbara Craton for which paleolatitudes had been determined. Samples at 2721 AE 4 Ma and 2718 AE 3 Ma differ by 27 or 3000 km.…”

Section: Longevity Of Geologic Featuresmentioning

confidence: 99%

Evolution of the Earth: Plate Tectonics Through Time

Sleep

2015

Treatise on Geophysics

View full text Add to dashboard Cite

Geochronology of a Late Archaean flood basalt province in the Pilbara Craton, Australia: constraints on basin evolution, volcanic and sedimentary accumulation, and continental drift rates

Cited by 112 publications

References 58 publications

Late Archean rise of aerobic microbial ecosystems

Late Archean rise of aerobic microbial ecosystems

The intensity of the geomagnetic field in the late-Archaean: new measurements and an analysis of the updated IAGA palaeointensity database

Evolution of the Earth: Plate Tectonics Through Time

Contact Info

Product

Resources

About