April 22, 1884 Tsunami: Southern England, United Kingdom

Reference #14326:

Haslett and Bryant (2008) have suggested that there was an associated tsunami. There are several reports of boats at moorings being swayed violently. For example, the Chelmsford Chronicle of 25th April notes that: “In the harbour the yachts and other vessels rocked considerably, and some men up the masts of one vessel were nearly thrown overboard by the unexpected vibrations.”

These observations may indicate seiching rather than a tsunami. The various newspapers provide very detailed descriptions of the effects of the earthquake in each village and town but don’t mention any anomalous waves. A subsequent review of the event by Medola and White (1885) states that the absence of any distinct movement of the river Colne was generally confirmed.

There was however a single report in the Eastern Daily Press of 23rd April 1884 that states that: “the sea is said to have rushed with restless force over the marshes [of East Mersea Island], receding some time afterwards, leaving thick deposits of sand behind, in some instances at incredible distances from the coast”, which is similar to descriptions of a tsunami. This is used by Haslett and Bryant (2008) to suggest that the earthquake created a tsunami. The earthquake itself is too small to have generated a tsunami and there is no evidence that a landslide was triggered. However there were reports of groundwater escape in the same area that ceased after two and half hours and that this water was laden with sand so there may have been some mixing of reports.

Reference #4215:

A mechanism for tsunami generation is problematic in these cases, but substantial ground waves were observed in the 1884 event that would have led to impulsive displacement of the seabed locally, which elsewhere have been linked to intense tsunami (Paulatto et al., 2007). Sea disturbance associated with a small earthquake (local magnitude,ML, 4.0) was also observed in 1859 in southwest England that may indicate the sensitivity of shallow water settings to small near-coastal earthquakes. It has been suggested that some of these earthquakes have shallow epicentres that may amplify their effects and so take on the characteristics of a higher magnitude event.