Magnetic Map of Qld grid first edition

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 Magnetic Map of Qld grid first edition has a cell size of 0.0025 degrees (approximately 270m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2003 by the None Government, and consisted of None line-kilometres of data at a line spacing between 200m and 10000m, and Nonem terrain clearance.

总磁场强度（Total Magnetic Intensity，简称TMI）数据用于测量地壳中成岩矿物含量差异所引发的地球磁场强度变化。磁异常可分为正异常（磁场强度高于正常值）与负异常（磁场强度低于正常值）两类，其类型取决于岩石的磁化率。该数据通过标准流程进行处理，以确保记录的响应仅源于地下岩石。处理后得到的数据集可通过解译揭示地下地质构造。经处理的数据由GA地球物理学家开展质量核查，以确保GA发布的最终数据符合使用要求。本昆士兰州地磁格网第一版的格网单元尺寸为0.0025度（约270米），数据单位为纳特斯拉（nanoTesla，简称nT）。用于生成该格网的数据于2003年由None政府采集，总测线长度为None公里，测线间距介于200米至10000米之间，地形离地高度为Nonem。