Paleoproterozoic basin development on the northern Yilgarn Craton, Western Australia

Occhipinti, Sandra; Hocking, R. M.; Lindsay, Mark; Aitken, Alan; Copp, Iain; Jones, Julie A.; Sheppard, S. C.; Pirajno, Franco; Metelka, Václav

doi:10.1016/j.precamres.2017.08.003

Cited by 31 publications

(56 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The work presented here relied on SOM, which can be seen as an extension of the k-means and c-means clustering algorithms used for lithological differentiation (Paasche and Tronicke, 2007;Carter-McAuslan et al, 2015;Li, 2015, 2016;Maag and Li, 2018;Ward et al, 2014;Singh and Sharma, 2018), with which it shares a number of characteristics. We can therefore assume that our findings may hold true for these techniques.…”

Section: Discussionmentioning

confidence: 99%

“…In contrast, the recovery of geological quantities from geophysical inversion has seen much less effort. Recent studies have started to rectify this by proposing the idea of lithological differentiation of inversion results (Paasche et al, 2010;Sun and Li, 2015;Paasche and Tronicke, 2007), which consists of the identification of lithologies from inversion results. While lithological differentiation is expected to hold much potential in mineral exploration, it still remains underexplored .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Towards plausible lithological classification from geophysical inversion: honouring geological principles in subsurface imaging

et al. 2020

Self Cite

View full text Add to dashboard Cite

Abstract. We propose a methodology for the recovery of lithologies from geological and geophysical modelling results and apply it to field data. Our technique relies on classification using self-organizing maps (SOMs) paired with geoscientific consistency checks and uncertainty analysis. In the procedure we develop, the SOM is trained using prior geological information in the form of geological uncertainty, the expected spatial distribution of petrophysical properties and constrained geophysical inversion results. We ensure local geological plausibility in the lithological model recovered from classification by enforcing basic topological rules through a process called “post-regularization”. This prevents the three-dimensional recovered lithological model from violating elementary geological principles while maintaining geophysical consistency. Interpretation of the resulting lithologies is complemented by the estimation of the uncertainty associated with the different nodes of the trained SOM. The application case we investigate uses data and models from the Yerrida Basin (Western Australia). Our results generally corroborate previous models of the region but they also suggest that the structural setting in some areas needs to be updated. In particular, our results suggest the thinning of one of the greenstone belts in the area may be related to a deep structure not sampled by surface geological measurements and which was absent in previous geological models.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Towards plausible lithological classification from geophysical inversion: honouring geological principles in subsurface imaging

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 99%

“…The development of the Yerrida Basin began with deposition of the c. 2200 Ma Windplain Group, followed by the 2180 to 105 1996 Ma Mooloogool and Bryah Groups (Occhipinti et al, 2017;Pirajno and Occhipinti, 2000). The rocks of the Windplain Group are representative of a shallow coastal and possible epicontinental setting (Occhipinti et al, 2017), while the rocks of the Bryah and Mooloogool Groups were deposited in relatively higher-energy and possible rift environments Pirajno and Adamides, 2000). Periods of magmatism are recorded primarily by the basaltic volcanic and intrusive rocks of the Killara and Narracoota Formations (Mooloogool and Bryah Groups, respectively), though other mafic intrusive 110 and extrusive rocks are observed in other formations (Juderina and Karalundi Formations, Occhipinti et al, 2017) and as dykes (Mueller, 2011).…”

Section: Introductionmentioning

confidence: 99%

“…The rocks of the Windplain Group are representative of a shallow coastal and possible epicontinental setting (Occhipinti et al, 2017), while the rocks of the Bryah and Mooloogool Groups were deposited in relatively higher-energy and possible rift environments Pirajno and Adamides, 2000). Periods of magmatism are recorded primarily by the basaltic volcanic and intrusive rocks of the Killara and Narracoota Formations (Mooloogool and Bryah Groups, respectively), though other mafic intrusive 110 and extrusive rocks are observed in other formations (Juderina and Karalundi Formations, Occhipinti et al, 2017) and as dykes (Mueller, 2011). The geodynamic evolution of the Yerrida Basin is interpreted as a pull-apart basin opening consistent with a trailing-edge marginal sag-basin (Pirajno and Occhipinti, 2000), progressing to a rift in the north (Bryah Sub-basin) (Occhipinti et al, 2017;Olierook et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Mapping undercover: integrated geoscientific interpretation and 3D modelling of a Proterozoic basin

Lindsay¹,

Occhipinti²,

LaFlamme³

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

Abstract. Gravity and three-dimensional modelling combined with geochemical analysis are used to examine the subsurface within, and below the poorly exposed Paleoproterozoic Yerrida Basin in central Western Australia. Understanding the structure of a region is important as key features indicating past geodynamic processes and tectonic activity can be revealed. However, in stable, post-depositional tectonic settings only the younger sedimentary units tend to be widely exposed rendering direct observation of basement and intrusive rocks impossible. Geophysical imaging and modelling can reveal the structure of a region under cover. High amplitude density anomalies around the basin cannot be reconciled with current geological knowledge in the case presented here. The density anomalies infer an abundance of buried and high-density material that is not indicated by the surface geology. A hypothetical causative source for the high-density anomalies is considered to be intrusion and extrusion of volcanic mafic rocks during rifting of the basin. The simplest and plausible stratigraphic attribution of these interpreted mafic rocks is to the Killara Formation within the Mooloogool Group. However, geochemistry reveals that the Killara Formation is not the only host to mafic rocks within the region. Mafic rocks present in the Juderina Formation have largely been ignored in previous descriptions of Yerrida Basin magmatism and results indicate that they may be far more substantial than once thought. Sulphur isotopic data indicates no Archean signature to the mafic rocks, a somewhat surprising result given the basement to the Basin is Archean Yilgarn Craton. It is proposed the mafic rocks were sourced from vents located to the north along the Goodin Fault or under the Bryah sub-basin and Padbury Basins. The conclusion is that the formation of the Yerrida Basin involves a geodynamic history more complex than previously thought. The utility to the approach described here is examined for application to cratonic sag-basin environments. This result highlights the value in geophysics and geochemistry to reveal complexity in the earlier geodynamic evolution of the basin that may be indiscernible from surface geology, but may have high importance for the tectonic development of the region and its mineral resources.

show abstract

3‐D Characterization of Detrital Zircon Grains and its Implications for Fluvial Transport, Mixing, and Preservation Bias

Markwitz

Kirkland

Mehnert

et al. 2017

Geochem Geophys Geosyst

View full text Add to dashboard Cite

Detrital zircon studies can suffer from selective loss of provenance information due to U‐Pb age discordance, metamictization, metamorphic overprinting and fluviatile transport processes. The relationship between isotopic composition and zircon grain shape, and how grain shape is modified during transport, is largely unknown. We combine X‐ray tomography with U‐Pb geochronology to quantify how fluvial transport affects 3‐D zircon shape, detrital age signature, and grain density along the Murchison River, whose catchment comprises Eoarchean to Early Paleozoic source rocks in Western Australia. We acquired tomographic volumes and isotopic data from 373 detrital zircons to document changes in size, shape and density in transport direction, and explore how grain shape, age spectra and the proportion of discordant material vary along the channel. Results show that shape characteristics are sensitive to transport distance, stream gradient, proximity to source material, and whether the source consists of primary or recycled zircons. With increasing transport distance, grain lengths decrease more than their widths. Furthermore, the loss of metamict grains occurs at a near constant rate, resulting in a linear increase of mean calculated zircon density by ca. 0.03 g/cm3 per 100 km transport distance. 3‐D grain shape is therefore strongly linked to detrital age signature, and mean grain density is a function of the absolute transport distance. 3‐D shape characteristics provide valuable information on detrital zircon populations, including the interaction between source materials with fluvial transport processes, which significantly affects preservation bias and, by inference, the representativeness of the sampled data.

show abstract

Paleoproterozoic basin development on the northern Yilgarn Craton, Western Australia

Cited by 31 publications

References 41 publications

Towards plausible lithological classification from geophysical inversion: honouring geological principles in subsurface imaging

Towards plausible lithological classification from geophysical inversion: honouring geological principles in subsurface imaging

Mapping undercover: integrated geoscientific interpretation and 3D modelling of a Proterozoic basin

3‐D Characterization of Detrital Zircon Grains and its Implications for Fluvial Transport, Mixing, and Preservation Bias

Contact Info

Product

Resources

About