Yandi Mine, Marillana Station, East Pilbara Shire, Western Australia, Australiai
|Regional Level Types|
|Marillana Station||- not defined -|
|East Pilbara Shire||Shire|
|Latitude & Longitude (WGS84):||22° 43' 24'' South , 119° 4' 51'' East|
|Latitude & Longitude (decimal):||-22.72340,119.08089|
|Owned/operated by:||BHP (85%), Itochu Minerals (8%)|
|Köppen climate type:||BWh : Hot deserts climate|
Iron ore mine operated and majority owned by BHP. This mine is different to the Yandicoogina iron ore mine a few kilometres east, also sometimes called Yandi, operated by Rio Tinto.
The mine is 90 kilometres north-west of Newman. Operations commenced in 1991 from the E2 and C5 pits. The mine has a capacity of 80 Mtpa, three processing plants, and two train loading facilities. Ore is railed to Port Hedland.
In September 2008, there were two fatalities at the mine within 10 days.
The Yandi orebody is part of an 80 kilometre long palaeo channel infill ore deposit. It is sub-divided into a series of mine areas, based on the natural mesa shaped landscape. This consists of mines Central Mesa Pits 1-5, Eastern Mesa Pits E1-E8, and Western Mesa Pits W1-W6.
The ore body is about 80 metres thick, with the majority of the ore obtained from the top 60 metres, the lower 20 metres being poorer grades. Old pits are infilled with overburden from newly developed pits. The normally dry Marillana Creek flows through the mine site, and had to be diverted.
The ore comes from a Tertiary pisolitic iron palaeo channel system, 80 kilometres long, incised into the shale, dolerite and banded iron formation dominated Weeli Wolli Formation, in the broad structural Yandicoogina Syncline. Most ore outcrops as low lying mesa, or is covered by up to 60 metres of colluvium and alluvium. The ore is found in the core of the syncline, east trending, east plunging, exposing the shallow dipping Brockman Iron Formation on both its flanks, and western closure.
The palaeo channel is saucer shaped in cross section, 450-750 metres wide, and 40 to 60 metres thick in the channel centre, thinning towards the margins. The top is weathered, silicified, or clay rich.
The ore, up to 80 metres thick, overlies a basal gravel bed. The basal gravel is irregular, consisting of cemented gravel of 1-2 cm hematite pebbles rimmed by black goethite, and siliceous cement 1-12 metres thick. The pisolitic unit contains a basal zone, 300 metres wide and 0-20 metres thick 45-57% Fe of pisolitic goethite and ocherous goethite clay on the lateral margins. Above this is the main pisolitic zone 40-70 metres thick, and 400 to 1100 metres wide, averaging 56-59% Fe.
These two zones are separated by a 1-5 metre zone of clay, or clay matrix conglomerate to massive vitreous goethite.
The deposit is a mass of cemented concretionary iron oxides occurring as irregular sub-rounded goethite clasts, up to 3 mm in diameter, separated by a loose matrix of brown to grey densely packed ore. This is either cemented rounded to sub-rounded iron oxide pisoliths, with some voids, and more commonly pseudo pisoliths of non iron oxides rimmed by goethite from iron charged groundwater.
Pisoliths form concentric shells with a goethite core, limonite, then an outer vitreous goethite. There is also the replacement of angular and sub-angular banded iron formation and shale by limonite on some specimens. Hematite at the deposit is subordinate to goethite.
Regions containing this locality
Select Mineral List TypeStandard Detailed Strunz Dana Chemical Elements
Commodity ListThis is a list of exploitable or exploited mineral commodities recorded from this region.
Mineral ListMineral list contains entries from the region specified including sub-localities
2 valid minerals.
Rock Types Recorded
Rock list contains entries from the region specified including sub-localities
Select Rock List TypeAlphabetical List Tree Diagram
Detailed Mineral List:
List of minerals arranged by Strunz 10th Edition classification
|Group 4 - Oxides and Hydroxides|
|Unclassified Minerals, Rocks, etc.|
List of minerals arranged by Dana 8th Edition classification
|Group 4 - SIMPLE OXIDES|
|Group 6 - HYDROXIDES AND OXIDES CONTAINING HYDROXYL|
|Unclassified Minerals, Mixtures, etc.|
List of minerals for each chemical element
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
|Priabonian - Lutetian|
33.9 - 47.8 Ma
Age: Eocene (33.9 - 47.8 Ma)
Stratigraphic Name: Robe Pisolite
Description: Pisolitic, oolitic and massive limonite, minor terrigenous siliciclastic material, goethite and hematite deposits; developed along palaeodrainage lines; dissected by present day drainage.
Comments: regolith; synthesis of multiple published descriptions
Reference: Raymond, O.L., Liu, S., Gallagher, R., Zhang, W., Highet, L.M. Surface Geology of Australia 1:1 million scale dataset 2012 edition. Commonwealth of Australia (Geoscience Australia). 
|Siderian - Neoarchean|
2300 - 2800 Ma
|Archean-Paleoproterozoic sedimentary and volcanic rocks|
Age: Precambrian (2300 - 2800 Ma)
Stratigraphic Name: Hamersley Group
Comments: Hamersley Basin
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529.