April 4, 1640 Earthquake: Roer Valley, Germany

Reference #43 says: "Three shocks were felt. The inside waters of Holland were much disturbed." This is from Mallet and Mallet (Reference #1879) that says, "Three very violent shocks. The ships in the ports of Holland were very much agitated, although it was quite calm." Vogt (Reference #3942), in his study of the original sources from this earthquake in northwestern Europe, says that these are accounts from the outer regions of the macroseismic area.

Reference #1879 records the local time as 3:15 a.m., and suggests three violent shocks. Locations for the felt area are "France, Belgium, and Holland; especially at Brussels, Antwerp, Mechlin, and Namur. Also at Frankfort, and in parts of Westphalia and Lorraine; altogether a space of about 360 leagues." Vogt (Reference #3942) cites a possible epicenter in the Roer Valley in Germany and explains that most anecdotal information comes from felt areas away from the epicenter. This was a widely felt earthquake. A tsunami is linked, but the conclusions are questionable.