Geographically, earth is made of volcanoes. After crore of thousands of years, it has settled down to a green valley. It is like ash on the top of the hidden fire.
So some portions are well cooled by nature and while some others are yet to get that much cooled.
Geographically, Japan and Indonesia were on the volcano open lid.
So this is the one reason for these two countries are being affected often by earthquakes.
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The Indonesia and Japanese archipelago is located in an area where several continental and oceanic plates meet. This is the cause of frequent earthquakes and the presence of many volcanoes and hot springs across