Fig. 6From: DigitSeis: software to extract time series from analogue seismogramsDigitization Example 3: 1966 Alaskan Twin Earthquakes. A section of long-period north–south recording from COL (College, Alaska) station on December 19, 1966. a Scanned image of 70 mm microfiche as loaded into DigitSeis. b Same image as (a) but with digitized traces for lines 12 (cyan) and 13 (magenta) superimposed on the imageBack to article page