March 2, 1923 Eruption of Ile des Cendres

The Ile des Cendres group of submarine volcanoes off the SE coast of Vietnam consists of two submarine cinder cones that formed ephemeral islands during an eruption in 1923 and two submarine lava cones of uncertain age. The 1923 eruption produced two small islands, one about 30 m high and about 450 m long, and the other only 30 m wide and 30 cm high. A third submarine cone reached to within 20 m of the surface. Additional submarine cones occur between Ile des Cendres and the Vietnam mainland (Bondarenko and Nadezhnyi, 1989). (reference #2432)

The Hon Tro earthquakes of 15/02/1923 and 02/05/1923: These earthquakes are related to eruption of the Hon Tro volcano (10.1 N, 109. E). According to Minh Do su (Minh's Dynasty Historical Book), Vol. 23, the volcanos eruptions and related shaking are described as: "Earthquakes were followed by roars sounded like thunders, the sea waters shot highly in the air during many days in the Phu Qui island, sometimes 4-5 times, sometimes 20-30 times a day". P.V. Thuc (2008) described activities of volcanos and earthquakes in the coastal zones of Central Vietnam as follows: "Before eruptions, starting from 15/02/1923 many places of Phan Theit, Cu lao Hon island were strongly shook, houses tilted, people could not stand but sea level did not disturb. The shakings lasted a week, and then when the Japanese ship Vacasamuru passed by, they observed a black column of smoke and a dense column of gaz of more than 2000 m height coupled with blasting sounds". Based on hydrohtermal and C14 data analysis, the authors conclude that the magma of the Hon Tro volcano was erupted from a depth of 60-70 km. (reference #12502)