Siljan Ring Siljan Ring The Siljan Ring () is a prehistoric impact crater in Dalarna, central Sweden. It is one of the 15 largest known impact craters on Earth and the largest in Europe, with a diameter of about . The impact that created the Siljan Ring occurred when a meteorite collided with the Earth's surface during the Devonian period, about 376.8 ± 1.7 Ma. This coincides around the first Devonian extinction, the Kellwasser Event or Late Frasnian extinction at 376.1 Ma ± 1.6 Ma. The effects of the impact can clearly be seen in the bedrock in the area. The Cambrian,
Mora (linguistics) long ē (eta: η) can be understood as a sequence of two short vowels: ee. Ancient Greek pitch accent is placed on only one mora in a word. An acute (έ, ή) represents high pitch on the only mora of a short vowel or the last mora of a long vowel ("é, eé"). A circumflex (ῆ) represents high pitch on the first mora of a long vowel ("ée"). In Old English, short diphthongs and monophthongs were monomoraic, long diphthongs and monophthongs were bimoraic, consonants ending a syllable were each a mora, and geminate consonants added a mora to the preceding