Terms not listed are as defined in the Collins English Dictionary
(4th Australian Edition - ISBN 0 00 472219 1).

A
aeolian Sediments deposited by the action of wind.
aeromagnetic survey A magnetic survey conducted from an aircraft.
Ag Silver
alluvial Sediments deposited by the action of rivers or streams.
alteration The change in the mineral composition of a rock, commonly due to hydrothermal activity.
alteration zone A zone in which rock-forming minerals have been chemically changed.
amphibolite A metamorphic rock composed mainly of the mineral amphibole.
antiform, anticline Fold in the form of an arch.
Archaean The oldest geological era - Older than 2,400 million years.
arenite Sedimentary rock comprised of sand-sized material - Sandstone.
argentiferous Silver bearing.
argillite Fine-grained (clay, silt) sedimentary rock.
arkose A sandstone consisting of feldspar and quartz grains cemented by a mixture of quartz and clay minerals.
As Arsenic.
Au Gold.
auriferous Gold bearing.
AusIMM Australasian Institute of Mining and Metallurgy.
azimuth Compass direction.

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B
basalt A dark, fine-grained extrusive igneous rock composed of feldspar and iron-magnesium rich minerals.
basement Older igneous and metamorphic rocks beneath usually unmetamorphosed sediments.
base-metal Copper, zinc, lead.
batholith Large mass of igneous intrusive rock.
BIF Banded Iron Formation. A rock consisting essentially of alternating bands of iron-oxides and cherty silica.
BLEG Bulk Leach Extractable Gold - a chemical analysis technique.
block, sub-block Mining tenement description: block = meridian block described as 1' latitude by 1' longitude, sub-block = part of a meridian block described as 30" latitude by 30" longitude.
boxwork The pattern of predominantly iron oxides left after the removal by weathering of sulphide minerals to form a gossan.
breccia Rock comprising angular fragments in a finer grained matrix.

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C
Cainozoic The geological era from 65 million years to 2 million years before present.
calc-alkaline The name given to a suite of rocks comprising the volcanic association basalt-andesite-dacite-rhyolite or the plutonic association
gabbro-diorite-granodiorite-granite. Calc-alkaline rocks are typically developed on the continental side of plate subduction zones.
calcrete Superficial gravels cemented by secondary calcium carbonate.
calc-silicate A metamorphic rock usually formed as the result of metamorphism of impure limestone or dolomite sediments.
carbonaceous Rock containing significant quantities of carbon usually derived from organic material, often in the form of graphite.
carbonate Mineral, usually associated with limestone or dolomites (or their metamorphosed equivalents), containing CO3.
cassiterite Mineral. Ore of tin.
chalcedony Fine-grained quartz often formed as the weathering product of silicarich rock.
chalcopyrite Sulphide mineral. Ore of copper.
chert Fine grained quartz rock usually occurring as thin layers in sedimentary sequences.
chlorite A dark mineral of the mica family.
chrysocolla Mineral. Hydrated copper silicate usually occurring in the weathered zone of copper deposits.
chrysotile Mineral. A common variety of asbestos.
clastic Pertaining to sedimentary rocks composed of fragments eroded from pre-existing rocks.
Co Cobalt.
colluvium Unconsolidated overburden transported by gravity.
complex An assemblage of rocks of various ages and origins intricately mixed together.
conglomerate Sedimentary rock composed of rounded, coarse, pebble to boulder sized fragments of pre-existing rocks.
costean A trench excavated in the surface for the purpose of geological investigation.
Cr Chrome.
Craton A relatively large and stable block of the Earths crust.
Cretaceous The geological era from 135 million years to 65 million years before present.
crocidolite Mineral. A common variety of asbestos.
Cu Copper.
cupriferous Copper bearing.
cuprite Mineral. Oxide ore of copper.
cut-off grade The lowest or highest assay value that is included in a resource estimate.

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D
dendritic Pertaining to branching drainage having the form of a tree.
detrital Particles or minerals derived from pre-existing rock by erosion.
diamond drilling Rotary drilling technique using diamond set or impregnated bits, to cut a solid, continuous core sample of the rock. The core sample is retrieved to the surface, in a core barrel, by a wireline.
dip The angle at which a rock stratum or planar structure is inclined from the horizontal. Also used in drilling for angle of drillhole from
horizontal.
dolerite A dark coloured medium grained igneous intrusive rock comprising the minerals pyroxene and feldspar.
dolomite A sedimentary rock composed of calcium and magnesium carbonates.
duricrust Layer of strongly cemented material in otherwise unconsolidated material at or near surface.
dyke A tabular body of intrusive igneous rock, crosscutting the host strata at a high angle.

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E
EM survey Electromagnetic survey. A method of measuring the alternating magnetic fields associated with electrical currents artificially or
naturally maintained in the subsurface.
epithermal Descriptive of mineral deposits formed in rock fissures at shallow depths and low temperatures by ascending mineralizing solutions
fault A fracture in rocks on which there has been movement on one side relative to the other.

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F
felsic Light coloured rocks containing an abundance of feldspars and quartz.
ferruginous Iron bearing. Usually pertains to iron-rich weathered rock.
fire assay Analytical technique involving heating a sample in a furnace to ensure complete extraction of all contained precious metal.
float Fragments of rock at surface that are loose and unattached to outcrop.
foreland basin A basin formed within a continental setting, often adjacent to a mountain range.
framboid Microscopic aggregate of pyrite grains in a roughly spherical form.

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G
g gram.
g/t grams per tonne.
g/t Au, g/t Ag grams gold per tonne, grams silver per tonne.
Ga Billion years ago.
gabbro A dark coloured coarse grained igneous intrusive rock comprising the minerals pyroxene and feldspar.
geochemistry survey Systematic collection of data on the variation of chemical elements in rocks and soils.
geomorphology The description and interpretation of landforms.
geophysical survey Systematic collection of data on the variation of physical properties in rocks and soils.
glacial till A rock containing boulders in a clay matrix deposited from the action of ice in the form of glaciers.
gneiss A metamorphic rock with compositional banding of light and dark minerals, often granitic in composition.
gossan The oxidised 'cap' to underlying primary sulphides.
graben A downthrown block between two parallel faults.
granite Medium to coarse grained igneous intrusive rock comprised primarily of quartz and feldspar minerals.
granitoid A field term for coarse grained felsic igneous rocks resembling granite in composition.
graphite A soft, black mineral form of carbon, often found in metamorphic rocks derived from carbonaceous sediments.
gravity survey Systematic measurement and collection of the earth's gravitational field at the surface at regular intervals. Used to discern different rock types based on associated variations with differences in the distribution of densities, and hence rock types.
greenschist A schistose metamorphic rock which owes its green colour and schistosity to abundant chlorite and lesser epidote and/or actinolite.
greenschist facies A classification of the metamorphic grade of a rock, diagnostically defined by the metamorphic formation of chlorite and biotite at generally lower pressures and temperatures.
greenstone belt General term applied to elongate zones of volcanic and sedimentary rocks, usually metamorphosed to greenschist facies, and usually in Archaean-age terranes.

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H
harzburgite A dark coloured ultramafic igneous intrusive rock composed of the minerals pyroxene and olivine.
hematite Mineral. Oxide ore of iron.
hydrothermal Pertaining to mineralising processes resulting from the circulation of hot water.

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I
indicated resource A resource sampled by drillhole where scientific data is known with a reasonable level of confidence but drillholes are too widely spaced to ensure continuity.
inferred resource A resource scientific data is not known with a reasonable level of confidence and drillholes are too widely spaced to ensure continuity.
intrusive Pertaining to igneous rocks emplaced into pre-existing rocks at depth.
IP survey Induced Polarization survey. An electrical geophysical survey technique measuring the magnetic field spontaneously induced in a
volume of rock by the application of an electric current. A technique often used to identify disseminated sulphide deposits.
ironstone Field term for iron-rich rocks the product of weathering.

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J
JORC Joint Ore Reserves Committee. The guidelines of the JORC Code
(1999) are observed in the calculation of ore resources and ore
reserves.

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K
komatiite Magnesium-rich mafic to ultramafic extrusive volcanic rock.

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L
lag Residual surficial material, comprising resistant fragments, such as quartz and ironstone.
lateritisation An extreme form of weathering common in tropical climates, in which silica an other constituents are removed, leaving a rock
characterised by a high proportion of alumina and/or iron oxide.
layer-parallel fault A fault the plane of which lies parallel to the strata of the affected rocks.
leucogranite A granite composed almost entirely of light coloured minerals.
limonite Generic term applied to minerals comprising hydrated oxide of iron. Common constituent of weathered, ferruginous rocks.
lineament A large scale linear feature evident on aerial photography, satellite imagery or regional geophysical surveys.
lithology A term usually applied to sediments referring to their general characteristics.

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M
Ma Million years ago.
mafic Descriptive of rocks composed dominantly of magnesium, iron and calcium-rich rock-forming silicates, and for rocks in which these
minerals are abundant.
magmatic Pertaining to molten rocks in the Earths crust. Precursor to igneous rocks.
magnesite Mineral. Magnesium carbonate.
magnetic anomalies Zones where the magnitude and orientation of the earth's magnetic field differs from adjacent areas.
magnetic survey Systematic collection of readings of the earth's magnetic field.
malachite Mineral. Carbonate ore of copper commonly found in the weathered portion of copper deposits.
marble Metamorphosed limestone.
Mesoproterozoic Middle Proterozoic era of geological time, 1,600 to 1,000 years ago.
mesothermal Mineral deposits formed (precipitated) at moderate temperatures.
metamorphic Pertaining to rocks altered by the action of heat and/or pressure.
metasediment Metamorphosed sediment.
metasomatised A metamorphic rock where material has been introduced from an external source during metamorphism.
migmatite A mixed rock comprising an original metamorphic rock extensively invaded by granitic material.
mineralisation The process of introduction of valuable elements into a rock body. Also a descriptive term for any body of economically valuable
minerals.
mineral resource A tonnage or volume of rock or mineralisation of intrinsic economic interest.
Mo Molybdenum.
molasse Thick sequences of sediments derived from the erosion of mountain ranges.
monzogranite A granular plutonic rock with a composition between monzonite and granite.
moraine An accumulation of sediment which has been transported and deposited by ice.
mylonite Very fine grained, usually foliated rock in elongate or linear zones caused by intense and prolonged shearing of the host rocks.

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N
Neoproterozoic Late Proterozoic era of geological time, 1,000 to 570 million years ago.
Ni Nickel.
normal fault A fault along which movement has placed younger rocks over older rocks.

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O
orogen A period of mountain building.
ortho- A prefix used in front of a metamorphic rock name indicating that rock derived from an igneous rock. Orthogneiss - gneissic rock
derived from igneous rock types.

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P
palaeodrainage Ancient river system, possibly remnant only as sediments deposited in the original river.
Palaeoproterozoic Early Proterozoic era of geological time, 2,500 to 1,600 million years ago.
Pb Lead.
Pd Palladium.
pelite Metamorphosed argillite.
peneplanation The end process in the cycle of erosion usually resulting in a flat or near flat land surface.
PGE Platinum Group Elements, Platinum Group Metals: Platinum, Palladium, Iridium, Osmium, Rhodium and Ruthenium. Often associated with Ni-Cu iron-sulphides, and generally hosted by maficultramafic rock types.
Phanerozoic Geological period covering the time from the Cambrian (`600My bp) to 2My bp.
phyllite A cleaved metamorphic rock midway between slate and schist.
pisolite Approximately spherical accretion of iron or carbonate minerals.
plunge The attitude of a line in a plane, which is used to define the orientation of fold hinges, mineralised zones and other structures.
plutonic Granitic igneous mass approximately cylindrical in shape placed at a high level in the Earths crust.
polymetallic Containing many metals.
porcelainite A fine grained quartz rock having the appearance of porcelain.
ppb parts per billion.
ppm parts per million.
precious metal Gold, silver, PGE.
prehnite-pumpellyite Minerals the presence of which defines low-grade, sub-greenschist facies metamorphism.
primary A rock or mineral that has remained unaltered since it was originally formed.
Proterozoic Geological period from approximately 2,400My to 600My before present.
Pt Platinum.
pyrite Mineral. Iron sulphide.
pyrrhotite Mineral. Iron sulphide.

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Q
quartz Mineral. Silicon oxide.
quartzite Metamorphosed sandstone composed predominantly of recrystallised quartz.
quartzo-feldspathic Descriptive term for rock composed predominantly of near equal amounts of quartz and feldspar.

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R
RAB Rotary Air Blast. A method of rotary drilling in which sample is returned, using compressed air, to the surface in the annulus between
drill-rod and the drill-hole. A relatively inexpensive and less accurate drilling technique.
radiometric Data relating to the radioactivity emitted by rocks at or near the earth's surface, usually collected by helicopter or fixed wing aircraft.
RC Reverse Circulation. A method of rotary drilling in which the sample is returned to the surface, using compressed air, inside the inner-tube of the drill-rod. A more accurate drilling technique than RAB, which minimises contamination.
regolith Generic name for all, usually unconsolidated, sediments covering and obscuring bedrock.
rift basin A large fault-bounded depression infilled with volcanic and/or sedimentary material.

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S
saprolite Partially weathered rock usually with original primary rock textures retained.
Sb Antimony.
schist Regionally metamorphosed rock characterised by parallel arrangement of constituent minerals and usually exhibiting an undulose cleavage.
secondary A rock or mineral formed as a consequence of alteration, usually by oxidation, of pre-existing minerals.
SEDEX deposit A sediment-hosted massive sulphide deposit, typically tabular to lensoidal in shape and range from centimetres to tens of metres thick. Multiple horizons may occur over stratigraphic intervals of 1000 metres or more. Sedimentary exhalative deposits currently produce a significant proportion of the world's Zn and Pb.
sedimentary basin A depression of large size into which sediments have been deposited.
sericite Fine mica introduced through metamorphism or alteration.
shale A fine grained sedimentary rock usually with a well defined cleavage.
shear zone A zone in which rocks have been deformed primarily in a ductile manner in response to applied stress
sheetwash A widely distributed, thin blanket of sediment deposited in a broad, poorly defined drainage.
siliciclastic Sedimentary rock composed predominantly of quartz.
silicified Pertaining to a rock where silica has been introduced through the agency of metamorphism or weathering to form a very fine grained
quartz cement.
sill An igneous intrusive rock emplaced into sediments with the parallel margins of the intrusive parallel to the layering of the host sediments.
sphalerite Mineral. Sulphide ore of zinc.
stratiform Bedded or layered.
stratigraphy The study of formation, composition and correlation of sedimentary rocks.
strike The direction in which a horizontal line can be drawn on a plane. Usually used in describing the general trend of a rock layer or
structure.
stromatolite Ancient marine organism related to algae and forming distinctive fossil dome or columnar structures in sedimentary rocks.
subduction zone Refers to the area in which two crustal plates meet and, due to convergence, one is 'subducted' beneath the other.
sulphide A mineral in which a metal or metals exists in combination with sulphur.
supergene Of, or relating to minerals and mineral deposits or enrichments formed near the surface, generally by descending solutions.
supracrustal Pertaining to rocks created at the surface (sedimentary and volcanic rocks).
synform, syncline A basin-shaped fold.
syntectonic Occurring or forming at the same time as deformation and metamorphism.

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T
tectonic An adjective used to relate a particular phenomenon to a structural or orogenic concept.
TEM survey Transient ElectroMagnetic survey - a variant of EM survey.
Tertiary The geological era from 65 million years to 0 million years before present. Often synonymous with Cainozoic.
tholeiitic A term applied to mafic or ultramafic rocks composed predominantly of magnesium-rich feldspar and pyroxene minerals.
tonalite A coarse grained plutonic rock similar to diorite in composition but containing quartz as 5% to 20% of the light coloured minerals.
tuff Usually fine grained volcanic ash.
turbidite Sediment deposited in a submarine environment from a gravitymobilised slurry.
ultramafic Igneous rocks consisting essentially of ferro-magnesium minerals and containing less than 45% silica, with trace quartz and feldspar.

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U
unconformable A term recognising a break in sedimentation in a sedimentary sequence.

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V
vein A tabular or sheet-like body of minerals, commonly quartz, injected into a fracture in pre-existing rocks.
VMS Volcanogenic Massive Sulphides. Mineral deposit formed by the exhalation of sulphide rich solutions and subsequent precipitation of sulphides onto the sea floor surrounding a hydrothermal vent.
volcanic Rock derived from volcanic activity - Usually lavas, tuffs or other volcanic debris.
volcaniclastic Pertaining to sedimentary clastic rock containing volcanic material.

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W
wallrock The country rock of a vein or lode.

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Z
Zn Zinc