GSNSW Batemans Bay Narooma magnetic first vd grid geodetic  


Authors / CoAuthors

Geophysical Acquisition & Processing Section

Abstract

Total magnetic intensity (TMI) data measures variations in the intensity of the Earth's magnetic field caused by the contrasting content of rock-forming minerals in the Earth crust. Magnetic anomalies can be either positive (field stronger than normal) or negative (field weaker) depending on the susceptibility of the rock. The data are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. This GSNSW Batemans Bay Narooma magnetic first vd grid geodetic is a first vertical derivative of the Total Magnetic Intensity grid for the Batemans Bay-Narooma, NSW, 1998. This grid has a cell size of 0.00049 degrees (approximately 50m). The grid has units of nanoTesla per km (or nT/km). The data used to produce the TMI grid was acquired in 1998 by the NSW Government, and consisted of 7792 line-kilometres of data at 250m line spacing and 60m terrain clearance. A Fast Fourier Transform (FFT) process was applied to the original grid to calculate the first vertical derivative grid.

Product Type

dataset

eCat Id

142102

Contact for the resource

  Point of contact

Commonwealth of Australia (Geoscience Australia)  
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia

Keywords

theme.ANZRC Fields of Research.rdf
  • EARTH SCIENCES
( Data centre )
  • NCI
( Discipline )
  • Earth sciences
( Discipline )
  • geophysics
( Feature type )
  • grid
( Place )
  • Australia
( Place )
  • NSW
( Project )
  • survey 746
( Theme )
  • GADDS2.0
( Theme )
  • magnetics
( Theme )
  • first vertical derivative
( Theme )
  • magnetism
( Theme )
  • palaeomagnetism
( Theme )
  • airborne digital data
( Theme )
  • geophysical survey
( Theme )
  • mag
( Theme )
  • 1vd
( Theme )
  • grid
( Theme )
  • raster
  • Published_External

Publication Date

2020-03-07T00:00:00

Creation Date

2020-03-07T00:00:00

Security Constraints

Australian Government Security ClassificationSystem    

Classification - unclassified

Legal Constraints

Creative Commons Attribution 4.0 International Licence    

Access - license

Use - license

Status

completed

Purpose

Maintenance Information

notPlanned

Topic Category

geoscientificInformation

Series Information

Lineage

This GSNSW Batemans Bay Narooma magnetic first vd grid geodetic is a first vertical derivative grid of the Total Magnetic Intensity (TMI) anomaly for the Batemans Bay-Narooma, NSW, 1998. The survey was acquired under the project No. 746 for the geological survey of NSW. A total of 7792 line-kilometres of data at a line spacing of 250m and 60m terrain clearance were acquired to produce the TMI grid. A first vertical derivative was calculated by applying a fast Fourier transform (FFT) process to the Total Magnetic Intensity grid of the Batemans Bay-Narooma, NSW, 1998 survey to produce this grid. This grid was calculated using an algorithm from the INTREPID Geophysics software package. The processed data are checked by GA geophysicists using standard methods for assessing quality to ensure that the final data are fit-for-purpose. The grid has a cell size of 0.00049 degrees (approximately 50m). The grid has units of nanoTesla per km (or nT/km). The first vertical derivative grid is very helpful for the enhancement of near surface features and structural features such as faults and dykes. Details of the specifications of individual airborne surveys can be found in the Fourteenth Edition of the Index of Airborne Geophysical Surveys (Percival, 2014). This Index is also available online at http://pid.geoscience.gov.au/dataset/79134. References: Intrepid Geophysics, http://www.intrepid-geophysics.com; Percival, P.J., 2014. Index of airborne geophysical surveys (Fourteenth Edition).

Parent Information

Geophysical Data Collection - Airborne Geophysics

UUID - c6b58f54-102c-19e9-e044-00144fdd4fa6,

eCat ID - 74512

Extents

[-36.3133, -35.4586, 149.8294, 150.4151]

Reference System

WGS84 (EPSG:4326)

Spatial Resolution

Service Information

Associations

Association Type - operatedOnBy

GSNSW Batemans Bay Narooma magnetic first vd grid geodetic NCSS    

Association Type - operatedOnBy

GSNSW Batemans Bay Narooma magnetic first vd grid geodetic OPeNDAP    

Association Type - operatedOnBy

GSNSW Batemans Bay Narooma magnetic first vd grid geodetic WMS    

Association Type - operatedOnBy

GSNSW Batemans Bay Narooma magnetic first vd grid geodetic WCS    

Downloads and Links

File available for download in various formats from the GADDS2 portal  

GSNSW Batemans Bay Narooma magnetic first vd grid geodetic file download  

GSNSW Batemans Bay Narooma magnetic first vd grid geodetic NCSS  

GSNSW Batemans Bay Narooma magnetic first vd grid geodetic OPeNDAP  

GSNSW Batemans Bay Narooma magnetic first vd grid geodetic WMS  

GSNSW Batemans Bay Narooma magnetic first vd grid geodetic WCS  

Source Information

This GSNSW Batemans Bay Narooma magnetic first vd grid geodetic includes airborne-derived TMI data for the Batemans Bay-Narooma, NSW, 1998 acquired for the geological survey of NSW