Comparing induced polarization responses from airborne inductive and galvanic ground systems: Lewis Ponds, New South Wales

Geophysics ◽  
2016 ◽  
Vol 81 (6) ◽  
pp. B179-B188 ◽  
Author(s):  
Kate Hine ◽  
James Macnae
Keyword(s):  
New South ◽  
Hanging Wall ◽  
New South Wales ◽  
Induced Polarization ◽  
Order Effects ◽  
Galvanic Current ◽  
Electromagnetic System ◽  
Near Surface ◽  
Polarization Effects ◽  
South Wales

We have evaluated the mapping of polarizable material using a Cole-Cole model to fit second-order effects in concentric-loop airborne electromagnetic system responses. At Lewis Ponds in New South Wales, an inverted ground dipole-dipole array data has accurately imaged in 3D disseminated sulfide extending above and around ore grade massive sulfides. The polarizable zone is present in the near-surface, where, from modeling, airborne systems may have sensitivity to the small inductive induced polarization effects. Although the inverted chargeability measured from galvanic current injection into the ground was spatially coincident with the mineralized target, the estimated chargeabilities from induced polarization effects in an airborne versatile time-domain electromagnetic survey were substantially displaced to the east. The airborne induced polarization response may be associated with finer grained mineralization in the hanging wall of the sulfide deposits, or have a quite different source, such as clays associated with faulting.

Observations of circulation and exchange processes in Jervis Bay, New South Wales

1992 ◽  
Vol 43 (6) ◽  
pp. 1487 ◽  
Author(s):  
PE Holloway ◽  
G Symonds ◽  
Vaz R Nunes
Keyword(s):  
New South ◽  
New South Wales ◽  
Additional Mechanism ◽  
Near Surface ◽  
South Wales ◽  
Circulation Current ◽  
Southern Side ◽  
Northern Side ◽  
Wind Currents ◽  
Coastally Trapped Waves

This paper discusses oceanographic observations obtained in and near Jervis Bay, a small coastal embayment of approximately 124 km2 situated on the New South Wales coast, during a series of measurement programmes spanning three years. Various mechanisms that drive water circulation within the bay and water exchange between the bay and the adjacent continental shelf are discussed. Current meter data from within the bay show surprisingly little correlation with the wind. Currents are characterized by persistent flows in one direction for periods of months, and it is suggested that influences from the shelf are responsible for driving the bay circulation. Flow through the bay entrance is weakly correlated with the wind at a period of around eight days, with near-surface inflow on the southern side of the entrance being in phase with deeper outflow on the northern side and vice versa. The shelf waters are well known for their coastally trapped waves. These have the potential to oscillate vertically the density surfaces on the shelf on a time scale of around eight days, and observations indicate that these waves are an additional mechanism driving circulation in the bay. The shelf waters are influenced by the warm East Australia Current and its eddies, and this appears to maintain a density contrast between the bay and the shelf for most of the year, with the shelf waters being less dense, which may be an additional mechanism driving bay circulation. Current-meter data from the bay entrance show a persistent northward current component in contrast to the strong southward flow of the East Australia Current on the shelf. Conductivity-temperature- depth data reveal cold, dense water flowing out of the bay during periods of strong winter cooling and the effects of warm eddies pushing warm water into the bay and displacing cold deeper water away from the bay. The heating/cooling cycle of the bay appears to be influenced by advection processes on the shelf as well as by aidsea heat and radiation exchanges.

Scattered native trees and soil patterns in grazing land on the Northern Tablelands of New South Wales, Australia

Soil Research ◽  
2007 ◽  
Vol 45 (3) ◽  
pp. 199 ◽  
Author(s):  
Brian R. Wilson ◽  
Ivor Growns ◽  
John Lemon
Keyword(s):  
New South ◽  
New South Wales ◽  
Tree Canopy ◽  
Deep Drainage ◽  
Grazing Land ◽  
Near Surface ◽  
Soil Layers ◽  
South Wales ◽  
Eastern Australia ◽  
Canopy Effect

Over large areas of south-eastern Australia, the original cover of native woodland has been extensively cleared or modified, and what remains is often characterised by scattered trees beneath which the ground-storey vegetation is largely grazed or otherwise managed. This study investigated the influence of scattered Blakely’s red gum (Eucalyptus blakelyi) trees on both near-surface and deeper soil layers in temperate grazed pastures on the Northern Tablelands of New South Wales, Australia. A significant canopy effect was observed with elevated soil pH, carbon, and nutrient status inside the tree canopy indicating soil enrichment in a zone around the tree. This effect, however, was largely restricted to the surface (0–0.20 m) soil layers. Chloride concentrations were elevated near to trees but only in the deeper soil layers, suggesting that a modified water use and deep drainage mechanism occurred near the trees. Close to the tree, however, a significant acidification was observed between 0.40–0.60 m depth in the soil, without any obvious depletion in other soil element concentrations. It is concluded that this acidification provides strong evidence in support of a ‘biological pumping’ mechanism that has been proposed elsewhere. Key questions remain as to the management implications of these results, whether the subsurface acidification that was observed is common among native Australian trees, if it might be persistent through time, and if this might be a soil issue that requires management.

Chemical and mineralogical transformations accompanying the weathering of basic volcanic rocks from New South Wales

Soil Research ◽  
1964 ◽  
Vol 2 (2) ◽  
pp. 218 ◽  
Author(s):  
DC Craig ◽  
FC Loughnan
Keyword(s):  
New South ◽  
New South Wales ◽  
Volcanic Rocks ◽  
Parent Rock ◽  
Steady Increase ◽  
Near Surface ◽  
South Wales ◽  
Alkaline Earths ◽  
Basic Volcanic ◽  
Mineral Transformations

An investigation has been made of the chemical and mineralogical transformations which have accompanied the weathering of six basic volcanic rocks from eastern New South Wales. Montmorillonite is initially formed from the destruction of the olivine, pyroxene, and plagioclase in the parent rock, but, in the near-surface horizons, this mineral is unstable and may form kaolinite, halloysite, or a poorly crystalline montmorillonite. The alumina content shows a steady increase up the profiles, whereas the alkalis, alkaline earths, and some of the silica have been lost in the ground-waters during the mineral transformations. Marked concentrations of iron and titanium occur at specific levels in some of the weathering profiles and explanations of these phenomena are given.

Owyheeite from Rivertree, New South Wales

1962 ◽  
Vol 33 (259) ◽  
pp. 315-319 ◽  
Author(s):  
L. J. Lawrence
Keyword(s):  
New South ◽  
New South Wales ◽  
The Other ◽  
Polarization Effects ◽  
Apparent Rotation ◽  
South Wales ◽  
Intimate Association

SummaryOptical and other microproperties of owyheeite Pb5Ag2Sb6S15 are presented and details given of a new locality for this rare sulpho-salt. Apparent rotation of the plane of polarization (3·5°), microhardness (112 V.H.N.), and polarization effects are all very similar to those of the other feather ores, jamesonite and boulangerite. An intimate association with pyrargyrite is further noted.

Zinc-manganese carbonates from Broken Hill, New South Wales

1986 ◽  
Vol 50 (355) ◽  
pp. 49-53 ◽  
Author(s):  
W. D. Birch
Keyword(s):  
New South ◽  
New South Wales ◽  
Natural Occurrence ◽  
Solid Solution Series ◽  
Near Surface ◽  
X Ray ◽  
Broken Hill ◽  
South Wales ◽  
Uniform Composition ◽  
Locality Information

AbstractSpecimens of honey-brown to pinkish-brown globular carbonates encrusting concretionary goethite–coronadite from the oxidized zone at Broken Hill, New South Wales, have compositions in the rhodochrosite–smithsonite series. This may be the first extensive natural occurrence of this solid-solution series. Growth of the carbonates occurred in zones which have near uniform composition. The ratio MnCO3/(MnCO3 + ZnCO3) for each zone bears a linear relationship to the measured d spacing for the 104 X-ray reflections. Because cerussite is the only other mineral associated with the Zn-Mn carbonates and because of an absence of detailed locality information, the paragenetic significance of these minerals cannot be determined. The solutions depositing them may have been derived from the near-surface equivalents of the Zinc Lode horizons.

Plants of New South Wales

2009 ◽  
Author(s):  
F. Von Mueller
Keyword(s):  
New South ◽  
New South Wales ◽  
South Wales

Notes and Sketches of New South Wales

2009 ◽  
Author(s):  
Louisa Anne Meredith
Keyword(s):  
New South ◽  
New South Wales ◽  
South Wales
Sign in / Sign up

Export Citation Format

Share Document