Geopolitical tension may have rocked markets in Japan. The island-country after the South Korea’s office of the president reported that North Korea had tested a nuclear weapon. The U.S. Geological Survey reported a 4.7 magnitude earthquake 230 miles north-east of Pyongyang, the North Korean capital. Intraday Japanese stock trading saw the Nikkei fall from a high of 9402.76 to a low of 9331.74 in the 30 minutes following the release of the news.