Dee ihe na-aga n'ihu maka paragraf a - Ihe dị ka pasent 10 nke ugwu na-agbọpụta ọkụ n'ụwa dị na Japan, nke dị na mpaghara nke enweghị nkwụsi ike nke ụwa. A na-akpụ ha site n'ịdị elu nke Pacific Plate na Philippine Sea Plate. A na-edekọ ihe dị ka ala ọma jijiji 1,500 kwa afọ, ala ọma jijiji ndị dị n'ike site na 4 ruo 6 abụghịkwa ihe ọhụrụ. Obere ala ọma jijiji na-eme ihe fọrọ nke nta ka ọ bụrụ kwa ụbọchị n'otu akụkụ nke mba ahụ ma ọ bụ n'akụkụ ya ọzọ, na-eme ka ụlọ ụfọdụ na-ama jijiji. Ala ọma jijiji ndị dị oké njọ na-adị obere; ndị a kasị mara amara na narị afọ nke 20 bụ: ala ọma jijiji nke Great Kantō nke 1923, nke mmadụ 130,000 nwụrụ na ya; na ala ọma jijiji nke Great Hanshin nke January 17, 1995, nke mmadụ 6,434 nwụrụ na ya. Na Mach 11, 2011, ala ọma jijiji mere na Japan
, bụ nke kacha buo ibu na mba ahụ na nke ise kacha buo ibu na ndekọ, dịka data US Geological Survey si kwuo. Ala ọma jijiji ndị na-eme n'okpuru oké osimiri na-emekwa ka ala ọma jijiji ndị na-eme n'ụsọ oké osimiri Japan na-akpa ike.