PARIS, France (AFP) — A rare volcano-triggered tsunami sparked by the eruption of Hunga Tonga-Hunga Ha’apai in Tonga could have been caused by shock waves or shifting underwater land, experts said Monday. “A volcanic-source tsunami event is rare but not unprecedented,” a post on the website for New Zealand’s geological hazard monitoring system GNS said Monday. GNS Tsunami Duty Officer Jonathan Hanson said it probably occurred in part thanks to a previous eruption of the […]