Canning Basin (Offshore), WA, 2007 (P1155), magnetic line data, AWAGS levelled

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. These line dataset from the Canning Basin (Offshore), WA, 2007 survey were acquired in 2007 by the WA Government, and consisted of 47084 line-kilometres of data at a line spacing between 750m and 750m, and 60m terrain clearance. To constrain long wavelengths in the data, an independent data set, the Australia-wide Airborne Geophysical Survey (AWAGS) airborne magnetic data, was used to control the base levels of the survey data. This survey data is essentially levelled to AWAGS.

总磁场强度（Total Magnetic Intensity, TMI）数据用于量化地壳内造岩矿物成分差异所引发的地球磁场强度变化。磁异常可依据岩石磁化率分为正异常（磁场强度高于常规水平）与负异常（磁场强度低于常规水平）。研究人员采用标准处理流程对数据进行预处理，以确保记录的磁场响应仅源自地下岩石。经处理得到的数据集可通过解译工作揭示地下地质结构。澳大利亚地质调查局（Geoscience Australia, GA）的地球物理学家会对处理后的数据开展质量核查，以确保该局发布的最终数据满足使用需求。本次测线数据集源自2007年西澳大利亚州（Western Australia, WA）坎宁盆地（近海）调查项目，于2007年由西澳大利亚州政府采集完成，总测线长度达47084线公里，测线间距为750米，航空测量离地高度为60米。为约束数据中的长波长分量，研究人员采用独立数据集——全澳航空地球物理调查（Australia-wide Airborne Geophysical Survey, AWAGS）航空磁测数据——对本次调查数据的基准水平进行校正。本次调查数据实质上已基于AWAGS数据完成平差处理。