Airborne geophysical survey: Southeastern California

Aeromagnetic data were collected along flight lines by instruments in an
aircraft that recorded magnetic-field values and locations. In the earlier
days of surveying, the only way to represent this data was to generate an
analog map with contour lines. This dataset is a representation of the
digitized contour lines either by following the lines or by choosing the
intersection of the contour and flight-line to create a value of the magnetic
field. The values presented are latitude, longitude, and map magnetic-field
values.

航空磁测数据由搭载于航空器的仪器沿飞行航线采集所得，该仪器可同步记录磁场强度与位置信息。在航空磁测的早期阶段，此类数据的唯一可视化呈现方式为绘制带等值线的模拟地图。本数据集为数字化等值线的重构成果，重构路径包括沿等值线进行追踪采样，或是选取等值线与飞行航线的交点以获取对应磁场强度数值。本次公开的数据包含纬度、经度与地磁图场强数值三类信息。