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  • <div>The A1 poster incorporates 4 images of Australia taken from space by Earth observing satellites. The accompanying text briefly introduces sensors and the bands within the electromagnetic spectrum. The images include examples of both true and false colour and the diverse range of applications of satellite images such as tracking visible changes to the Earth’s surface like crop growth, bushfires, coastal changes and floods. Scientists, land and emergency managers use satellite images to analyse vegetation, surface water or human activities as well as evaluate natural&nbsp;hazards.</div>

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    Gravity data measure small changes in gravity due to changes in the density of rocks beneath the Earth's surface. The data collected 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 National Gravity Compilation 2019 includes airborne DGIR image is produced from the 2019 Australian National Gravity Grids B series. These gravity data were acquired under the project No. 202008. The grid The grid represented in this image has a cell size of 0.00417 degrees (approximately 435m). The data are given in units of um/s^2, also known as 'gravity units', or gu. The %%MV_DATASETS/SURVEY_NAME% are derived from ground observations stored in the Australian National Gravity Database (ANGD) as at September 2019, supplemented by offshore data sourced from v28.1 of the Global Gravity grid developed using data from the Scripps Institution of Oceanography, the National Oceanic and Atmospheric Administration (NOAA), and National Geospatial-Intelligence Agency (NGA) at Scripps Institution of Oceanography, University of California San Diego. Airborne gravity and gravity gradiometry data were also included to provide better resolution to areas where ground gravity data was not of a suitable quality. Out of the approximately 1.8 million gravity observations, nearly 1.4 million gravity stations in the ANGD together with Airborne Gravity surveys totaling 345,000 line km and 106,000 line km of Airborne Gravity Gradiometry were used to generate this grid. The ground and airborne gravity data used in this grid has been acquired by the Commonwealth, State and Territory Governments, the mining and exploration industry, universities and research organisations from the 1940's to the present day. Station spacing for ground observations varies from approximately 11 km down to less than 1 km, with major parts of the continent having station spacing between 2.5 and 7 km. Airborne surveys have a line spacing ranging from 0.5 km to 2.5 km. The image shows de-trended global isostatic residual anomalies over Australia and its continental margins. This National Gravity Compilation 2019 includes airborne DGIR image (DGIR) was obtained by subtracting 3 quantities (i.e., the near-field isostatic correction, the far-field isostatic correction, and a first order trend correction) from Complete Bouguer Anomaly data (CBA) of the 2019 Australian National Gravity Grids B series.

  • ASTER Geoscience GIS products now available for the Gawler-Curnamona region in South Australia (AUSGEOnews title) Geoscience Australia, in collaboration with CSIRO and PIRSA are releasing a suite of 14 new ASTER mosaiced products for a significant part of the Gawler-Curnamona region. About 110 ASTER scenes have been mosaiced and processed into geoscience products that can be quickly and easily integrated with other datasets in a GIS. The products have been pre-processed and calibrated with available HyMap data and provide basic mineral group information such as Ferric Oxide abundance, AlOH group distribution as well as mosaiced and levelled false colour and regolith ratio images. These images, along with accompany notes are available for free ftp download online at: ftp://ftp.arrc.csiro.au/NGMM/Gawler-Curnamona ASTER Project/

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    Gravity data measure small changes in gravity due to changes in the density of rocks beneath the Earth's surface. The data collected 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 National Gravity Compilation 2019 includes airborne - CSCBA 0.5VD grid is derived from the 2019 Australian National Gravity Grids B series. These gravity data were acquired under the project No. 202008. The grid has a cell size of 0.00417 degrees (approximately 435m). This gravity anomaly grid is derived from ground observations stored in the Australian National Gravity Database (ANGD) as at September 2019, supplemented by offshore data sourced from v28.1 of the Global Gravity grid developed using data from the Scripps Institution of Oceanography, the National Oceanic and Atmospheric Administration (NOAA), and National Geospatial-Intelligence Agency (NGA) at Scripps Institution of Oceanography, University of California San Diego. Airborne gravity and gravity gradiometry data were also included to provide better resolution to areas where ground gravity data was not of a suitable quality. Out of the approximately 1.8 million gravity observations, nearly 1.4 million gravity stations in the ANGD together with Airborne Gravity surveys totaling 345,000 line km and 106,000 line km of Airborne Gravity Gradiometry were used to generate this grid. The ground and airborne gravity data used in this grid has been acquired by the Commonwealth, State and Territory Governments, the mining and exploration industry, universities and research organisations from the 1940's to the present day. Station spacing varies from approximately 11 km down to less than 1 km, with major parts of the continent having station spacing between 2.5 and 7 km. Airborne surveys have a line spacing ranging from 0.5 km to 2.5 km. Terrain corrections to gravity were calculated using both offshore bathymetry and onshore topography data. A first vertical derivative was calculated by applying a fast Fourier transform (FFT) process to the complete spherical cap Bouguer anomaly grid of the 2019 Australian National Gravity Grids B series to produce this grid. The grid shows a half vertical derivative of the complete Bouguer anomalies (B series) over Australia and its continental margins.

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    Gravity data measure small changes in gravity due to changes in the density of rocks beneath the Earth's surface. The data collected 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 National Gravity Compilation 2019 tilt grid is derived from the 2019 Australian National Gravity Grids A series. These gravity data were acquired under the project No. 202008. The grid has a cell size of 0.00417 degrees (approximately 435m). This gravity anomaly grid is derived from ground observations stored in the Australian National Gravity Database (ANGD) as at September 2019, supplemented with offshore data sourced from v28.1 of the Global Gravity grid developed using data from the Scripps Institution of Oceanography, the National Oceanic and Atmospheric Administration (NOAA), and National Geospatial-Intelligence Agency (NGA) at Scripps Institution of Oceanography, University of California San Diego. Out of the approximately 1.8 million gravity observations, nearly 1.4 million gravity stations in the ANGD with marina data were used to generate this grid. The ground gravity data used in this grid has been acquired by the Commonwealth, State and Territory Governments, the mining and exploration industry, universities and research organisations from the 1940's to the present day. Station spacing varies from approximately 11 km down to less than 1 km, with major parts of the continent having station spacing between 2.5 and 7 km. Terrain corrections to gravity were calculated using both offshore bathymetry and onshore topography data. A tilt filter was then applied to the complete spherical cap Bouguer anomaly (A series) to produce this grid covering Australia and its continental margins.

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    Gravity data measure small changes in gravity due to changes in the density of rocks beneath the Earth's surface. The data collected 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 National Gravity Compilation 2019 includes airborne DGIR tilt grid is produced from the 2019 Australian National Gravity Grids B series. These gravity data were acquired under the project No. 202008. The grid has a cell size of 0.00417 degrees (approximately 435m). The data are derived from ground observations stored in the Australian National Gravity Database (ANGD) as at September 2019, supplemented by offshore data sourced from v28.1 of the Global Gravity grid developed using data from the Scripps Institution of Oceanography, the National Oceanic and Atmospheric Administration (NOAA), and National Geospatial-Intelligence Agency (NGA) at Scripps Institution of Oceanography, University of California San Diego. Airborne gravity and gravity gradiometry data were also included to provide better resolution to areas where ground gravity data was not of a suitable quality. Out of the approximately 1.8 million gravity observations, nearly 1.4 million gravity stations in the ANGD together with Airborne Gravity surveys totaling 345,000 line km and 106,000 line km of Airborne Gravity Gradiometry were used to generate this grid. The ground and airborne gravity data used in this grid has been acquired by the Commonwealth, State and Territory Governments, the mining and exploration industry, universities and research organisations from the 1940's to the present day. Station spacing for ground observations varies from approximately 11 km down to less than 1 km, with major parts of the continent having station spacing between 2.5 and 7 km. Airborne surveys have a line spacing ranging from 0.5 km to 2.5 km. The grid shows a tilt of the de-trended global isostatic residual (DGIR) anomalies over Australia and its continental margins. The DGIR grid was obtained by subtracting 3 quantities (i.e., the near-field isostatic correction, the far-field isostatic correction, and a first order trend correction) from Complete Bouguer Anomaly data (CBA) of the 2019 Australian National Gravity Grids B series. A tilt filter was calculated by applying a fast Fourier transform (FFT) process to the DGIR grid of the 2019 Australian National Gravity Grids B series to produce this grid. A tilt filter is a ratio of the vertical derivative to the total horizontal derivative and is used for detection of edges of geological units.

  • The Landsat series of satellites commenced acquiring remotely sensed data with the launch of Landsat 1 in 1972. The Landsat satellites travel at an altitude of 705 kilometres and provide coverage of the entire globe every 16 days. The Multispectral Scanner (MSS) sensor has been the primary Earth-observing instrument. MSS images in four spectral bands (called Bands 4-7 on LS1,2&3 and 1-4 on LS 4&5) covering the visible and near infrared regions of the electromagnetic spectrum. The MSS ground swath is 185 kilometres wide, with a nominal 80 metre pixel resolution. The archive of ACRES MSS data dates from 1979 onwards. ACRES MSS archive contains data from the following Landsat satellites: Landsat 2 commenced November 1979, ceased Feb 1982 Landsat 3 commenced November 1979 ceased August 1982 Landsat 4 commenced August 1982, ceased May 1984 Landsat 5 commenced 9 April 1984, ceased November 1997 - Band 4 (original band 7) data poor quality from 29 April 1994 - Band 4 (original band 7)switched off permanently 20 August 1995 Note that MSS data from Landsat 3 & 4 is of poor quality and requirements for this data need to be discussed with ACRES prior to purchase.

  • The RADARSAT satellite was developed by the Canadian Space Agency (CSA) and was launched on 4 November 1995. It has a C-band, Synthetic Aperture Radar (SAR) sensor on board. The SAR is an active microwave sensor capable of imaging earth resource targets regardless of time of day, cloud, haze or smoke cover of an area. The instrument is classified "active" as it emits the energy necessary to image the earth's surface. In contrast, "passive" or "optical" sensors rely on the sun's reflected energy to image the earth. This sensor can operate in a variety of imaging modes to suit a range of applications. Depending on the beam mode, the SAR ground swath widith varies between 50 and 500 kilometres, and the pixel resolution varies between 10 and 100 metres. The sensor has HH polarisation. ACRES Radarsat archive consists of extensive coverage from August 1997 to late 1999. ACRES currently do not have an agreement with RSI but can acquire data if downlink is granted by RSI.

  • The Landsat series of satellites commenced acquiring remotely sensed data with the launch of Landsat 1 in 1972. Landsat satellites travel at an altitude of 705 kilometres and provide coverage of the entire globe every 16 days. Landsat 7, launched on 15 April 1999, carries the Enhanced Thematic Mapper Plus (ETM+). As the name suggests, the ETM+ sensor is similar to the TM sensor but has some added features. It provides imagery in the same seven spectral bands as the TM sensor with 30 metre resolution, but has an added panchromatic band with 15 metre pixel resolution. ETM+ also has an enhanced thermal band with a 60 metre resolution. Its ground swath is 185 kilometres. A full scene is approximately 184 kilometres by 172 kilometres. The archive of ACRES products includes ETM+ data from 6 July 1999 onwards.

  • The JERS-1 satellite was developed by the National Space Development Agency of Japan (NASDA). JERS-1 was launched in February 1992 and operated until 11 October 1998. The satellite traveled at an altitude of 568 kilometres and provided coverage of the entire globe every 44 days. The L-band, Synthetic Appeture Radar (SAR) sensor was the primary Earth-observing instrument. The SAR is an active microwave sensor capable of imaging earth resource targets regardless of time of day, cloud, haze or smoke cover of an area. The instrument is classified "active" as it emits the energy necessary to image the earth's surface. In contrast, "passive" or "optical" sensors rely on the sun's reflected energy to image the earth. The SAR ground swath is 75 kilometres wide, with a nominal 18 metre pixel resolution. The sensor has HH polarisation. ACRES JERS SAR acquisition commenced in September 1993 and ended in October 1998.