| Note: | No times noted - Echinus has been observed in eruption approximately 150 times this season. In June and early July the interval was fairly regular at approximately 1 hour and 50 minutes. Then the interval became shortened and is now (and has been for approximately one month) about 1 hour and 15 minutes. On August 18, 6 consecutive eruptions were observed; the longest interval was 90 minutes, the shortest 71 minutes, the average was 82 minutes. The eruptions of Echinus are fairly uniform and last from 3 to 6 minutes. A few bursts in each eruption always reach 100 feet - - several higher have been observed. Each eruption consists of 100 to 130 bursts. ¶ On several occasions the interval of Echinus has been greatly lengthened and on each occasion, the water in the crater has been of a reddish tint. The usual color is a deep green. What condition this indicates is no[t] known. ¶ The usual pattern consists of filling the crater, runoff on the west side, and a gradually increased boiling in the center of the pool. Under normal conditions, eruption follows after 5 minutes of boiling. ¶ Echinus has been very regular this year. |
