East Kimberley 2016 aerogravity survey — horizontal component data

Horizontal gravity components measured by the Sander Geophysics’ AIRGrav system in the East Kimberley 2016 aerogravity survey were released on 20 April 2017. The horizontal component datasets and a short supplementary technical report by Sander Geophysics have been added to the survey data package that can be downloaded from the Geo Downloads website.

The horizontal component data complement the vertical gravity data released on 23 February 2017 and can be used to provide an estimate of the variation of the gravity vector and gradient tensor over the survey area. Note that the gravity components are defined using an east–north-up system where the normal gravity of the earth is a vector pointing upwards.

Figure 1 shows images of the three components of the 2500m-spatially filtered ‘gravity anomaly vector’ as measured in Cartesian coordinate space (Gx, Gy, Gz). The values used have been taken from the following located datasets:

Component Path in data package Channel name
Gz — …\Z_Component\Located_data\ASEG-GDF2\GRAV.DAT GrvBGL2500m_267
Gx — …\E_N_Components\Located_data\ASEG-GDF2\GRAV_EN.DAT GRVBGL2500M_267-E
Gy — …\E_N_Components\Located_data\ASEG-GDF2\GRAV_EN.DAT GRVBGL2500M_267-N

Also shown in Figure 1 are the Cartesian components transformed to spherical coordinates as total magnitude, azimuth from north, and inclination from the vertical, where:

EK component equations

Figure 2 shows images of the six independent components of the anomaly tensor computed as the gradients of the measured Gx, Gy, Gz values in each of the three directions:

Table1

Also shown in Figure 2 is an image of the 3D analytical signal, EK component equation

The derived images in Figures 1 and 2 in georeferenced jp2 format and their source grids in ERMappper format are also included in the updated survey data package under the ‘Derived_grids’ directory.

 

Figure 1. East Kimberley 2016 aerogravity survey — anomaly vector data

Cartesian coordinates (top); spherical coordinates (bottom); 100 km grid lines
Table2

Table3

Figure 2. East Kimberley 2016 aerogravity survey — anomaly tensor data

Table4

GSWA database and online systems FREE training, 2017

Find out how to access geoscience data online and understand our systems at this FREE training course.

Systems include: WA

PERTH
The Perth training has been divided into separate sessions: one for mining companies/geologists (morning) and one for prospectors (afternoon).

KALGOORLIE
The Kalgoorlie training is open to anyone (full day).

Register
To register for this free training, send an email to publications@dmp.wa.gov.au including your details (name, company name, telephone number), with the location and date of the training you wish to attend. For the Perth session, please indicate whether you wish to attend the mining companies/geologists (morning) or prospectors (afternoon) training.

Spotlight on a product

Report 161 Geochronology of the Rudall Province, Western Australia: implications for the amalgamation of the West and North Australian Cratons
by DW Maidment

Spotlight on a product U–Pb zircon dating of igneous and metasedimentary rocks from the Rudall Province has revealed aspects of an extended, multiphase history that has implications for models of the assembly of Proterozoic Australia. Detrital zircon dating has identified metasedimentary units of possible Neoarchean to early Paleoproterozoic age, and a possible cover succession deposited  after c. 1794 Ma.

The Krackatinny Supersuite in the eastern part of the province yields ages of 1589–1549 Ma and has a range of geochemical compositions consistent with emplacement in a magmatic arc or a rift developed in thickened continental crust. Felsic magmatism and high-grade metamorphism at 1330–1285 Ma reflects a major tectono-thermal event, and possibly dates the Yapungku Orogeny, previously considered to have taken place at c. 1800–1765 Ma. This event has been linked with the amalgamation of the West and North Australian Cratons, and might indicate assembly later than previously thought. Go to DMP eBookshop to download a free PDF copy and accompanying zipped data files.

New releases

Reports

Reports Cover
Report 161 Geochronology from the Rudall Province, Western Australia: implications for the amalgamation of the West and North Australian Cratons
Plus accompanying downloadable zip files
by Maidment, DW

Reports Cover
Report 166 Thermo-mechanical evolution of orogeny in the Musgrave Province
by Walsh, A

Records

Reports Cover
Record 2017/4 Geological reconnaissance of the southern Murraba Basin, Western Australia
by Haines, PW and Allen, HJ

Reports Cover
Record 2017/6 TARGET 2017, Perth, Australia: abstracts
edited by Wyche, S and Witt, WK

Subscribe to Fieldnotes

Subscribe to Fieldnotes Fieldnotes is a quarterly publication released by GSWA to provide the State's exploration industry and other geoscientists with an update on our latest work and ongoing programs. The publication provides updates on other GSWA products and services and is available free from the Information Centre located on the first floor of Mineral House, 100 Plain Street, East Perth 6004. Find past issues of Fieldnotes here or subscribe to receive a hard copy by emailing publications@dmp.wa.gov.au.

Access GSWA products

You can view and download maps, reports, and digital information free of charge from our website.
Click on these links to take you to the download or launch page for that product:

Hard copies
Maps, USB data packages, and nine premium publications are available to purchase as hard copies from the eBookshop or the First Floor counter at Mineral House, 100 Plain Street, East Perth WA 6004. A new online cart and payment system is in place. Records, Reports, Bulletins and other non-series books cannot be purchased in hard copy but are all available as PDFs to view and download free of charge.

Contact us

Contact us

For information on publications, email publications@dmp.wa.gov.au
or telephone +61 8 9222 3459/ fax +61 8 9222 3444.

For information on digital data, email the Digital Data Administrator on gsd.dda@dmp.wa.gov.au or telephone +61 8 9222 3816.

Physical address
Mineral House
100 Plain Street
East Perth WA 6004
www.dmp.wa.gov.au/gswa
For more information about GSWA and its products, go to our website.