出典:Wikipedia
出典:『Wikipedia』 (2010/11/14 16:06 UTC 版)
In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided. It spans the time between 245 ± 1.5 Ma and 228 ± 2 Ma (million years ago). The Middle Triassic is divided into the Anisian and Ladinian ages or stages.