A METHOD FOR THE DIRECT INTERPRETATION OF MAGNETIC ANOMALIES CAUSED BY TWO‐DIMENSIONAL VERTICAL FAULTS

Geophysics ◽  
1978 ◽  
Vol 43 (1) ◽  
pp. 179-188 ◽  
Author(s):  
I. R. Qureshi ◽  
A. M. Nalaye
Keyword(s):  
New South ◽  
Ground Surface ◽  
Magnetic Anomalies ◽  
Two Dimensional ◽  
Field Profile ◽  
Master Curves ◽  
Antisymmetric Part ◽  
Western Margin ◽  
South Wales ◽  
Direct Interpretation

The magnetic anomaly profile across a two‐dimensional block faulted at right angles to the ground surface looks very similar to the anomaly profile across a dike and can be decomposed into a symmetric part and an antisymmetric part. Following Koulomzine et al (1970), these parts are separately analyzed and expressions for diagnostic parameters derived. The values of these parameters, obtained from the components of a field profile, help in distinguishing the source (dike or faulted block) and in determining the geometry of the block analytically or with the aid of six master curves. Some features of the application and sensitivity of the method are discussed. Field examples are given from the western margin of the Perth basin in Western Australia and from Lachlan foldbelt in New South Wales.

Effects of bait-station design on the uptake of baits by non-target animals during control programmes for foxes and wild dogs

2003 ◽  
Vol 30 (2) ◽  
pp. 147 ◽  
Author(s):  
Alistair S. Glen ◽  
Chris R. Dickman
Keyword(s):  
Red Fox ◽  
New South ◽  
Ground Surface ◽  
Target Species ◽  
South Wales ◽  
Bait Station ◽  
Control Programmes ◽  
Substantial Risk ◽  
Bait Stations ◽  
Wild Dogs

The removal of non-toxic baits was monitored during a simulated trail-baiting programme for foxes and wild dogs in the central tablelands of New South Wales. Ninety-one buried baits were removed by a number of species including spotted-tailed quolls, Australian brush-turkeys, superb lyrebirds, small mammals, wild dogs and a red fox. Spotted-tailed quolls were significantly less likely to remove baits buried under the ground surface than baits buried in raised mounds of soil. By means of remote photography, individual quolls were identified removing 3–4 baits in one night from bait stations 400 m apart. The results of this study show that spotted-tailed quolls and other non-target species may face substantial risk of consuming baits intended for wild dogs and foxes. However, the risk of poisoning spotted-tailed quolls may be significantly reduced by appropriate planning. Recommendations are made to increase the target-specificity of baiting programmes in areas with populations of spotted-tailed quolls.

The effects of temperature and salinity on Acacia harpophylla (brigalow) (Mimosaceae) germination

2006 ◽  
Vol 28 (2) ◽  
pp. 175 ◽  
Author(s):  
S. M. Reichman ◽  
S. M. Bellairs ◽  
D. R. Mulligan
Keyword(s):  
Large Scale ◽  
High Salinity ◽  
New South ◽  
Ground Surface ◽  
Mine Wastes ◽  
Mining Companies ◽  
South Wales ◽  
Salinity Levels ◽  
Effects Of Temperature ◽  
Mine Sites

Acacia harpophylla F. Muell. (brigalow) used to naturally occur over a range of about 50 000 km2 in Queensland and New South Wales, Australia. Large scale clearing for agriculture has reduced the area to less than 20 000 km2 and it is estimated that 20–25% of vertebrate fauna living in brigalow communities will become locally extinct as a result of the current clearing induced loss of habitat. Some coal mining companies in central Queensland have become interested in providing habitat for the endangered bridle nail-tailed wallaby that lives in brigalow vegetation. However, there is little known about establishment techniques for brigalow on mine sites and other disturbed ground; an understanding of brigalow biology and ecology is required to assist in the conservation of this threatened vegetation community and for re-creation of bridled nail-tail wallaby habitat in the post mining landscape. Brigalow is an unusual species of Acacia because it is not hard-seeded and germinates readily without the need to break seed-coat imposed dormancy. Germination trials were undertaken to test the ability of brigalow seed to germinate with a range of temperatures and salinity levels similar to those experienced in coal mine spoil. Optimum germination was found to occur at temperatures from 15 to 38°C and no germination was recorded at 45°C. Brigalow was very tolerant of high salt levels and germinated at percentages greater than 50% up to the highest salinity tested, 30 dS/m. Germination of greater than 90% occurred up to an electrical conductivity of 20 dS/m. The results indicate brigalow seed can be sown in summer when rains are most likely to occur, however, shading of the seed with extra soil or mulch may ensure the ground surface does not become too hot for germination. Because of its ability to germinate at high salinity levels, brigalow may be suitable for use in saline mine wastes which are common on sites to be rehabilitated after mining.

scholarly journals CAPTURE AND THREE DIMENSIONAL PROJECTION OF NEW SOUTH WALES STRATA PLANS IN LANDXML FORMAT

2017 ◽  
Vol IV-4/W5 ◽  
pp. 57-63
Author(s):  
B. Harding ◽  
A. Foreman
Keyword(s):  
New South ◽  
New South Wales ◽  
Three Dimensional ◽  
Ground Surface ◽  
Three Dimensions ◽  
Future Research ◽  
Single Source ◽  
Real Property ◽  
South Wales ◽  
Major Reform

New South Wales is embarking on a major reform program named Cadastre NSW. This reform aims to move to a single source of truth for the digital representation of cadastre. The current lack of a single source cadastre has hindered users from government and industry due to duplication of effort and misalignment between databases from different sources. For this reform to be successful, there are some challenges that need to be addressed. <br><br> “Cadastre 2034 – Powering Land &amp; Real Property” (2015) published by the Intergovernmental Committee on Surveying and Mapping (ICSM) identifies that current cadastres do not represent real property in three dimensions. In future vertical living lifestyles will create complex property scenarios that the Digital Cadastral Database (DCDB) will need to contend with. While the NSW DCDB currently holds over 3 million lots and 5 million features, one of its limitations is that it does not indicate land ownership above or below the ground surface. <br><br> NSW Spatial Services is currently capturing survey plans into LandXML format. To prepare for the future, research is being undertaken to also capture multi-level Strata Plans through a modified recipe. During this research, multiple Strata Plans representing a range of ages and development types have been investigated and converted to LandXML. Since it is difficult to visualise the plans in a two dimensional format, quality control purposes require a method to display these plans in three dimensions. Overall investigations have provided Spatial Services with enough information to confirm that the capture and display of Strata Plans in the LandXML format is possible.

Nomogram for the direct interpretation of magnetic anomalies due to long horizontal cylinders

Geophysics ◽  
1986 ◽  
Vol 51 (11) ◽  
pp. 2156-2159 ◽  
Author(s):  
T. K. S. Prakasa Rao ◽  
M. Subrahmanyam ◽  
A. Srikrishna Murthy
Keyword(s):  
Direct Method ◽  
Linear Equations ◽  
Arbitrary Point ◽  
Magnetic Anomalies ◽  
Horizontal Cylinder ◽  
Empirical Method ◽  
Master Curves ◽  
Hilbert Transforms ◽  
Direct Interpretation ◽  
Horizontal Cylinders

One of the widely used geometrical configurations for magnetic interpretation is the long horizontal circular cylinder. Gay (1965) provides a set of master curves for the interpretation of magnetic anomalies of these bodies. Rao et al. (1973) formulates functions of the anomaly at several distances from an arbitrary point, and the linear equations thus formed are solved for coefficients related to the parameters of the causative body. Prakasa Rao and Murthy (1976) propose an empirical method for rapid interpretation. Atchuta Rao and Ram Babu (1980), Mohan et al. (1982), and Sampath Kumar and Prakasa Rao (1984) describe methods based on Hilbert transforms. Radhakrishna Murthy et al. (1980) propose a method based on two components of the anomalous magnetic field. With the exception of the direct method of Prakasa Rao and Murthy (1976), the other methods mentioned involve reduction of field curves and then matching with master curves, solving linear equations, performing Hilbert transformations, and computation of derivatives, respectively. Hence they are not suitable for direct and rapid interpretation. This note contains a simple nomogram for the magnetic effect due to an arbitrarily magnetized horizontal cylinder.

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