Paleomagnetic evidence for periods of intense oxidative weathering, McKinnons mine, Cobar, New South Wales

Opalisation of the Great Artesian Basin (central Australia): an Australian story with a Martian twist

“…, paleomagnetic dating(Idnurm & Senior 1978;Schmidt & Ollier 1988;McQueen et al 2002;Pillans 2005Pillans , 2007Smith et al 2009), and K-Ar and Ar-Ar dating of alunite(Bird et al 1990;Newberry 2005) and Mn-oxide(Vasconcelos & Conroy 2003;Vasconcelos et al 2008) largely confirmed a long and continuous period of weathering from ca 45 Ma to present. Indeed, Cenozoic weathering has profoundly reworked and rejuvenated the Late Cretaceous to Paleocene weathering(Taylor & Shirtliff 2003).…”

“…Idnurm & Senior 1978;Smith et al 2009), oxygen isotope dating (Bird & Chivas 1993) and K-Ar and Ar-Ar dating of alunite and hollandite (Bird et al 1990;Newberry 2005;Vasconcelos et al 2008) suggest that weathering and opalisation may have occurred during a few discrete weathering episodes from Late Cretaceous to Cenozoic (Jones & Segnit 1966;Wopfner et al 1974;Senior & Mabbutt 1979;SimonCoinçon et al 1996). More recently, radiocarbon dating on carbon inclusions in opal from Lightning Ridge indicates ages <46 ka (e.g.…”

The remote determination of magnetic remanence

“…As a starting point for this research we have used APWP data from Clark and Lackie (2003) and Smith et al (2009) which provides data from 15 to 430 million years. Further research is required to provide the best average path with estimates of uncertainties at each step.…”

Paleochannels and Patches: A Geoarchaeological Assessment of Silcrete Sources in the Cumberland Plain, Eastern Australia

“…This suggests that deposition of the gravels was contemporaneous with laterite (ferricrete) development during the relatively warm, humid, seasonal climate of the Miocene. This climate promoted ferricrete formation across southern Australia (e.g., Smith, Pillans, & McQueen, ) and iron oxide mobility around the Lapstone Structural Complex (Bishop, Hunt, & Schmidt, ). However, the uplift that initiated development of the drainage system in which the St. Marys Formation was deposited probably occurred in the Paleogene, as previously mentioned.…”