57 research outputs found
Climatic oscillations during the Precambrian era
A remarkably regular cyclicity with a fundamental period of ~11–12 cycles is preserved in the 680 million year old Elatina formation of South Australia. All but one of the many periods present can be interpreted as resulting from the combined influences of the sunspot cycle and the lunar nodal tide - in particular, beating between these two cycles gives rise to a long period phase alternation. Available paleontological evidence is used to constrain the lunar distance 680 Ma ago, thereby constraining the length of the lunar nodal tide. We then infer from the beat period that the sunspot cycle was 10.8 ± 0.2 years, which is in agreement with independent astronomical evidence suggesting that the sunspot cycle would then have been some 3–10% shorter than it is at present. Although this interpretation is not consistent with the 12.0 year sunspot cycle counted by Williams and Sonett (1985), we demonstrate that unavoidable random errors made in discriminating unusually indistinct varves gives rise to a systematic overcount of varves of this magnitude. The clarity of this evidence for solar and lunar signals in the climate 680 Ma ago lends support to reports of their importance today.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42576/1/10584_2004_Article_BF00143906.pd
The contribution of geochronology to Precambrian studies in Western Australia
Volume: 62Start Page: 21End Page: 3
Application of borehole imagery in iron ore: examples from Mount Whaleback, Western Australia
Petrography of martite–goethite ore and implications for ore genesis, South Flank, Hamersley Province, Western Australia
Revised correlations in the early Precambrian Hamersley Basin based on a horizon of resedimented impact spherules
Accelerating Finite-Volume Based Lattice Boltzmann Flow Solutions on a Graphics Processing Unit Using CUDA
HELLENISTIC GLAZED WARES FROM ATHENS AND SOUTHERN ITALY: ANALYTICAL TECHNIQUES AND IMPLICATIONS
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