Figure 1
From: Lateral Variation of Crustal Lg Attenuation in Eastern North America

The essential geological blocks of eastern Canada. The Mid-Continent Rift (MCR) is shown by the gray shaded area. Solid black lines show boundaries of geological blocks. Abbreviations are Belcher thrust-fold belts (BL) and Kapuskasing Uplift (KP). Numbers are associated to the locations of Q anomalies in the tomography results. The figure is generated from GMT, which is an open source software available at: http://gmt.soest.hawaaii.edu.