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 GSWA Charnley TMI Grid Geodetic has a cell size of 0.00042 degrees (approximately 45m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2011 by the WA Government, and consisted of 145084 line-kilometres of data at a line spacing between 200m and 800m, and 50m terrain clearance.

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 GSWA Prince Regent Montague TMI Grid Geodetic has a cell size of 0.00167 degrees (approximately 182m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2011 by the WA Government, and consisted of 145084 line-kilometres of data at a line spacing between 200m and 800m, and 50m terrain clearance.

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 GSWA Perenjori TMI Grid Geodetic has a cell size of 0.00042 degrees (approximately 43m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2011 by the WA Government, and consisted of 121110 line-kilometres of data at 200m line spacing and 50m terrain clearance.

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 GSWA Corrigin TMI Grid Geodetic has a cell size of 0.00042 degrees (approximately 43m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2012 by the WA Government, and consisted of 115492 line-kilometres of data at 200m line spacing and 50m terrain clearance.

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 GSWA Perth Basin North TMI Grid Geodetic has a cell size of 0.00083 degrees (approximately 87m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2011 by the WA Government, and consisted of 93199 line-kilometres of data at 400m line spacing and 60m terrain clearance.

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 GSWA Lake Muir TMI Grid Geodetic has a cell size of 0.00063 degrees (approximately 63m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2012 by the WA Government, and consisted of 126090 line-kilometres of data at a line spacing between 200m and 300m, and 50m terrain clearance.

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 GSWA Cape Leeuwin TMI Grid Geodetic has a cell size of 0.00083 degrees (approximately 85m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2011 by the WA Government, and consisted of 101882 line-kilometres of data at a line spacing between 200m and 400m, and 50m terrain clearance.

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 GSWA Perth Basin South TMI Grid Geodetic has a cell size of 0.00083 degrees (approximately 86m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2011 by the WA Government, and consisted of 80718 line-kilometres of data at 400m line spacing and 60m terrain clearance.

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 Streaky Bay - TMI grid (AWAGS) has a cell size of 0.0004 degrees (approximately 41m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2018 by the SA Government, and consisted of 90670 line-kilometres of data at 200m line spacing and 60m terrain clearance. To constrain long wavelengths in the grid, an independent data set, the Australia-wide Airborne Geophysical Survey (AWAGS) airborne magnetic data, was used to control the base levels of the survey grid.