804216.fig.0011a
(a)
804216.fig.0011b
(b)
Figure 11: Assessment of terrain effects for Area 2. Hypothetical terrain effects in (a) are compared to patterns in the observed RTP aeromagnetic data in (b) to identify anomalies caused solely by topographic relief formed on magnetic Quaternary deposits. Note the lack of correlation along the stream bank on the east side of San Luis Creek. Faults from LiDAR (black) and those from HGM of RTP data (white) are overlain. Letter labels are for discussion purposes. (a) Hypothetical magnetic field computed from digital elevations using uniform magnetic susceptibility of 0.010 SI and height and Earth’s field parameters to match the RTP observed data. Digital elevations for the computation were derived from the LiDAR data, gridded at 25-m interval. (b) Observed RTP aeromagnetic data. Northeast illumination and color scales are identical for both images.