Iceland 's location astride the Mid-Atlantic Ridge , where the Eurasian and North American Plates are moving apart , is partly responsible for this intense volcanic activity , but an additional cause is necessary to explain why Iceland is a substantial island while the rest of the ridge mostly consists of seamounts , with peaks below sea level .
Iceland 's position over the Mid-Atlantic Ridge is partly responsible for this intense volcanic activity . It is not understood why Iceland is an island , but the rest of the ridge consists of seamounts , with peaks below sea level .