FIELD GEOLOGY OF THE SHOALHAVEN DISTRICT  (PART 24)

CHAPTER 16: References and Glossary

References 

Andrews EC: “Report on the Yalwal Gold Field” (Min.Res.NSW, 9) 1901 

Branagan DF and Packham GH: “Field Geology of NSW” (Science Press) 1967 

Card GW and Jaquet JB: “The Geology of the Cambewarra Mountain, NSW” (Rec.Geol.Surv.NSW, 8, 261) 1903 

Harper LF: “The Geology of the Gerringong District” (Rec.Geol.Surv.NSW, 8(2) 94) 1905 

Harper LF: “Geology and Mineral Resources of the Southern Coalfield” (Geol.Surv.NSW Mem 7) 1915 

Nashar B: “Geology of the Sydney Basin” (Jacaranda) 1967 

Packham GH (Ed): “The Geology of NSW” (J.Geol.Soc.Aust. 16 pt 1) 1969 

Paix JG: The Geology of the Shoalhaven Shire” (Shoalhaven Shire Council) 1968 

Taylor TG: “Sydneyside Scenery” (Angus and Robertson) 1958 

Ulladulla and Wollongong Geological Sheets and Explanatory Notes: (Dep. Mines NSW) 1966   

Year 12 Geology Class at Westley Park September 1984

Glossary: Rock and Mineral Names 

AGGLOMERATE Coarse, angular, pyroclastic rock 

AMETHYST Purplish variety of quartz 

AMPHIBOLES Mineral group, complex aluminosilicates 

ANDESINE Member of the plagioclase family of felspars ANDESITE Volcanic rock composed mainly of andesine and ferromagnesian minerals 

APLITE Fine grained dyke rock often found intruding coarse igneous rocks 

ARKOSE Sedimentary rock rich in felspars; may be derived from weathered granite 

ARSENOPYRITE Mineral, FeAsS, commonly called mispickel or arsenical pyrites 

AUGITE Dark mineral of complex formula, one of the pyroxene group 

BASANITE Volcanic rock resembling basalt, but containing minerals such as nepheline in addition 

BIOTITE Common dark coloured variety of mica 

BORNITE Peacock copper ore, Cu5FeS4, frequently displays an iridescent purple tarnish 

BRECCIA Fragmental rock composed of angular fragments. May be pyroclastic but finer than agglomerate 

CASSITERITE Mineral, SnO2, tin oxide, stream tin CHALCEDONY Waxy variety of quartz composed of microscopic crystals 

CHALCOPYRITE Golden copper ore, CuFeS2 

CHERT Sediment or residue composed largely of minute quartz particles 

CHLORITE Green micaceous mineral, commonly formed during metamorphism or weathering 

DOLERITE Common basic igneous rock of medium crystal size ESSEXITE Igneous rock resembling gabbro, but containing some nepheline 

FELSPAR Large group of aluminosilicate minerals, present in most rocks 

FLUORITE Mineral whose formula is CaF2 

GABBRO Plutonic igneous rock composed mainly of plagioclase, olivine, and pyroxenes 

GALENA Common lead mineral, PbS 

HAEMATITE Common iron ore, Fe2O3 

HORNBLENDE Dark mineral of complex formula, one of the amphibole group 

HORNFELS Fine grained metamorphic rock, the result of the intense heating of a silty sedimentary rock 

ILMENITE Mineral whose formula is FeTiO3 

JASPER Coloured impure of chalcedony 

LABRADORITE One of the plagioclase family of felspars LAMPROPHYRE Intrusive igneous rock rich in phenocrysts of ferromagnesian minerals 

LATERITE Residue of weathering, rich in iron and aluminium oxides 

LATITE Volcanic rock containing approximately equal parts of plagioclase and potassium felspars 

LITHIC SANDSTONE Sandstone composed largely of rock fragments 

MAGNETITE Dark magnetic iron mineral, Fe3O4 

MONZONITE Plutonic rock, similar in composition to latite NEPHELINE Rock forming mineral, (Na,K)Al SiO4 

NORITE Variety of gabbro 

OLIVINE Common family of greenish rock forming minerals, (Fe,Mg)2SiO4 

ONYX Variety of chalcedony composed of coloured, parallel bands ORTHOCLASE Potassium felspar, KAlSi3O8 

PEGMATITE Coarse igneous dyke rock usually found intruding bodies of granite 

PHYLLITE Metamorphic rock, midway between slate and schist PLAGIOCLASE Family of sodium-calcium felspars, ranging from NaAlSi3O8 (albite) to Ca Al2Si2O8 (anorthite) 

PYRITE Common brassy mineral, FeS2 iron pyrites, fool’s gold PYROLUSITE Manganese dioxide, MnO2 

PYROXENES Mineral group, represented by ABSi2O6 where A and B are metals 

QUARTZ FELSPAR PORPHYRY Common intrusive rock, containing phenocrysts of quartz and felspars 

QUARTZITE Metamorphic rock derived from sandstone RHYOLITE Flow banded volcanic rock related to granite in composition 

RUTILE Titanium dioxide, 

TiO2 SCHIST Metamorphic rock in which micaceous minerals are dominant 

SHALE Fine grained, layered sedimentary rock 

SILTSTONE Fine grained sedimentary rock in which layering is not prominent 

SLATE Fine grained metamorphic rock notable for its well developed cleavage 

SPHALERITE Zinc blende, ZnS 

SPOTTED SLATE Slate in which individual crystals are prominent STANNITE Complex ore mineral, Cu2FeSnS4 

SYENITE Plutonic igneous rock, composed essentially of orthoclase and ferromagnesian minerals 

TRACHYTE Volcanic rock related to syenite 

TUFF Fine grained pyroclastic sediment 

ZEOLITES Group of hydrated aluminosilicate minerals 

ZIRCON Zirconium silicate ZrSiO4   

Upturned Strata Shoalhaven River September 1978

Glossary: Descriptive terms 

ACIDIC  As applied to igneous rocks, containing more than 66% SiO2 by analysis  

ADIT Horizontal mine passage from the surface AMGYDALOIDAL Applied to volcanic rocks, meaning contains cavities (amygdales) filled with secondary minerals 

ANTICLINE Fold in which strata are arched upwards BASEMENT Older, more altered rocks lying beneath a sedimentary basin 

BASIC As applied to igneous rocks, containing less than 52% SiO2 by analysis, but more than 45% 

BATHOLITH Large body of intrusive igneous rock, commonly granitic in appearance  

BRACHIOPODS Group of marine invertebrates, having two dissimilar shells (valves), each of which is bilaterally symmetrical CLASTIC DYKE Body of sediment forced by pressure into cracks in the beds above or below 

COLUMNAR JOINTING Pattern of cracks caused by cooling which breaks a body of rock into columns, commonly hexagonal CONCRETION Body of mineral formed around a nucleus within the fabric of a rock 

CORRELATE The determination of the age equivalence of various rock formations 

CRINOIDS Group of marine organisms characterised by a cup, with radiating arms, attached to the sea floor by a stem 

CROSS BEDDING Arrangement of strata at an angle to the horizontal caused by current deposition 

DEUTERIC Term applied to alteration of an igneous rock by solutions after crystallisation has ceased 

DYKE Intrusive body cutting across adjacent rocks 

ERRATIC Applied to transported rock fragments foreign to the area where found 

ESTUARINE Applied to the region where fresh water drainage systems meets the sea 

FACIES As applied to sediments, the nature of the sedimentary material 

FERROMAGNESIAN Containing iron and magnesium FLUORESCENCE Emission of visible light by a substance when exposed to ultraviolet rays 

GANGUE The nonmetalliferous components of an ore body GLENDONITE Type of concretion common in Permian sediments which crystallised in near freezing bottom mud 

GRAPTOLITES Extinct group of marine organisms, found in floating colonies 

GROUNDMASS Material between the phenocrysts in a porphyritic rock 

GRYKE Solution groove on a limestone surface 

HYDRATION Combination with water 

IGNEOUS Formed from the molten or partially molten state INLIER 

Body of rock surrounded by younger rocks, produced by erosion INTERMEDIATE As applied to igneous rocks, containing between 52 and 66% SiO2 by analysis 

INTRUSION A body of igneous rock invading an older rock ISOCLINAL Applied to folds in which the limbs are practically parallel 

JOINT Rock fracture 

LACCOLITH Sill-like intrusion which has domed up the overlying rocks 

MESA Flat topped, cliff bound mountain 

METAMORPHIC Applied to rocks which have been formed by the effect of heat, pressure etc on existing rocks 

MIDDEN Aboriginal refuse heap 

MOLLUSC Marine organism characterised by a fleshy foot MONOCLINE Local steepening of the dip of strata  

NORMAL FAULT Displacement of strata resulting from tension within the rock 

OROGENIC Mountain building 

OUTLIER Body of rock surrounded by older rocks, produced by erosion 

OXIDISED As applied to ore bodies, the uppermost, weathered region 

PALAEONTOLOGY Study of former life as revealed by fossils PHENOCRYSTS Relatively large crystals in an igneous rock, usually ones which crystallised earlier 

PLUTONIC  Formed deep within the earth 

POLYZOA Group of marine, colonial organisms 

PORPHYRY Igneous rock containing phenocrysts PSEUDOMORPH Crystal produced by the alteration or replacement of another mineral, but retaining the original shape PYROCLASTIC Applied to sediments produced by explosive volcanic activity 

RACE Channel cut to convey water, usually for alluvial mining REVERSE FAULT Displacement of strata caused by compression within the rock 

SEDIMENTARY Applied to rocks deposited in layers SERPENTINE Rock forming minerals frequently derived from the alteration of ferromagnesian minerals 

SILICIFIED Replaced or cemented by silica 

SILL Body of igneous rock forced between strata 

SINK HOLE Depression caused by solution in a limestone body SLUMP Sediment that has moved down a slope, causing disturbance of the original bedding 

SPHEROIDAL WEATHERING Type of weathering which causes outer layers to peel off, forming rounded boulders 

STACK Small coastal island not yet removed by marine erosion STRATIGRAPHY Study of layered sedimentary rocks STRIATIONS Subparallel grooves, sometimes caused by glacial movement 

STRIKE Course or bearing of an outcrop, usually applied to sedimentary rocks, dykes, veins etc 

SYNCLINE Fold in which strata are arched downwards. TECTONIC Applied to the deformation of the Earth’s crust TERRACE Benches produced by deposition and erosion of sediment 

TOPOGRAPHIC Term applied to the surface relief of the Earth TUFF Fine grained pyroclastic material 

TWINNING Tendency of crystals, when growing, to share faces, edges etc 

ULTRABASIC As applied to igneous rocks, containing less than 45% SiO2 by analysis 

ULTRAVIOLET RADIATION Rays lying outside the violet end of the visible spectrum 

UNCONFORMITY Erosional surface separating younger and older rocks; a time gap 

VESICULAR Containing small gas cavities or vesicles 

VUGH Cavity in a rock frequently lined with crystals 

WASHOUT Channel cut through sediment which is later filled in itself 

WATER TABLE Surface below which rock openings are filled with water 

XENOLITH Applied to foreign rock material found within a body of igneous rock 

Volcanic Agglomerate Bombo December 1968