...Jason M. Huberty; Hiromi Konishi; Philipp R. Heck; John H. Fournelle; John W. Valley; Huifang Xu Abstract We report silician magnetite from banded iron formation (BIF) in the Dales Gorge Member of the Brockman Iron Formation, Hamersley Group, Western Australia. Magnetite mesobands typically...

... the basis for an assessment of the conditions of riebeckite formation in the Dales Gorge Member, Hamersley Group, Western Australia. Computed values of S 298 ° , Δ H ƒ,298 ° , Δ G ƒ,298 ° for riebeckite are 657.3 J/mol K, -10058.30 kJ/mol, and -9365.2 kJ/mol, respectively. At constant temperature riebeckite...

...-formation, the Dales Gorge Member of the Hamersley Group. It coexists with hematite, magnetite, quartz, ankerite, stilpnome-lane, and riebeckite. The ferri-annite can be chemically subdivided into two groups, A and B. The group A variety contains 4 to 7 wt.% Al 2 O 3 and has light reddish brown (= X...

...W. E. Ewers; R. C. Morris Abstract A drill core consisting of unaltered banded iron-formation from Paraburdoo, Western Australia, representing the entire Dales Gorge Member of the Brockman Iron Formation, has been analyzed in short units of about 300 mm or in groups of units of up to 1 m...

...Figure 4. Examples of photogrammetry models constructed for the Dales Gorge Member field sections using an unmanned aerial vehicle. (A) Textured 2.5D mesh of section Mt Jack East with the position of the ground control point markers indicated by the blue flags. Marker 4 is positioned in the lower...

... sedimentary deposits in Earth’s Precambrian rock record, consisting of alternating iron-rich (hematite, magnetite, and siderite) and silicate/carbonate (quartz, clay-like minerals, dolomite, and ankerite) layers. Based on chemical analyses from banded iron formation units of the 2.48 Ga Dales Gorge Member...

... for the former presence of hydrous ferric oxyhydroxides that formed from the oxidation of dissolved ferrous iron in seawater. However, textural evidence for the origin of hematite is equivocal. New petrographic results show that hematite in unmineralized BIF from the ca. 2.5 Ga Dales Gorge Member of the Brockman...

... a period of continental extension and enhanced heat flow within sedimentary basins to the south of the Paraburdoo Range. Heated basinal brines were focused by the NW-striking, steeply SW dipping 4E and 4EE normal faults and reacted with BIF of the Dales Gorge and Joffre members. The warm to hot (160°–255°C...

...P. L. C. Grubb Abstract Petrographic studies of a bore core section through the Dales Gorge Member of the Brockman Iron Formation, supported by experimental gel runs, indicate a complex paragenesis of associated ferroan silicate minerals in the Wittenoom Gorge area. The primitive silicate phases...