Airborne geophysical survey: Northern Great Valley - Wilbur Springs, 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飞行器的测量仪器沿飞行航线采集，同步记录磁场强度值与位置信息。在早期航空磁测作业阶段，此类数据唯一的可视化呈现方式为绘制带有等值线的模拟地图。本数据集为数字化等值线的成果形式：可通过追踪等值线完成数字化，或选取等值线与飞行航线的交点以获取对应磁场强度数值。数据集包含的参数为纬度、经度与测点磁场强度值。