The magnetic susceptibility of major rock units are similarly displayed. A larger contrast is apparent but the range of susceptibility is typically very wide.
Statistical outliers are understandable since many local factors affect the magnetic susceptibility measurements including local weathering, metamorphism, alteration, and small magnetite veins. Trying to correlate a small-scale phenomena with macroscopic geology is never straight-forward. A finer categorization of rock units is underway to help resolve the association between geology and geophysics.
The photo by Sue Karl shows graywacke turbidites of the Descon Formation.
 |
 |