South Norris Pool is located across the path from Spiteful Geyser in the Upper Geyser Basin of Yellowstone. South Norris Pool was a muddy spring or a mudpot depending on moisture conditions. It's activity increased until the park service was forced to place a wooden railing around the pool. Then at about 1600 on October 4, 1998 Spiteful Geyser became muddy and began overflowing more heavily than normal. South Norris Pool Geyser (SNPG) appeared sometime between the late afternoon on October 4, 1998 and the next morning. SNPG is definitely connected to Spiteful Geyser because an eruption by SNPG causes Spiteful's pool to drop 6 inches or so below it's normal bathtub mark level. After an eruption of SNPG Spiteful overflows heavily. Both Spiteful and SNPG looked muddy but were clearing as of early October 1998.

In early October 1998, the interval of SNPG ranged between 9 and 25 minutes with most of the eruptions centered at about 20 minutes. Durations ranged from about 1.5 to 5.5 minutes with most around 3.5 minutes. Short durations often caused the next interval to be short also. An eruption by Spiteful always caused SNPG's pool to drop by several feet and caused its eruptions to be weak and unpredictable for several hours.

In the early days of the park this area was covered over and used as a parking lot. An oily soil layer can be seen in the early pictures. The crater around SNPG continued to grow with each eruption. A sinter ledge was slowly appearing out of the softer overburden. The northeast corner of the crater (top left in the photos below) seems to be weaker and is rapidly growing toward North Norris Pool. It had not broken through as of October 1998. Photographing this geyser was difficult due to the railing surrounding the crater.

South Norris Pool Geyser Crater 1998/10/05 11:00 MDT:

South Norris Pool Geyser Crater Later in the week showing much more erosion 1998/10/11 09:00 MDT:

South Norris Pool Geyser (oil layer in lower right corner) 1998/10/05 11:00 MDT:

A deep drain after a Spiteful eruption:

A movie of SNPG 1998/10/05 11:24 MDT showing an eruption with water higher than the railing( estimated 8' above the pool) South Norris Pool Geyser movie (2.7 Mb, 11 sec, sound)

A movie of SNPG 1998/10/07 1054 MDT showing an eruption without the railing visible South Norris Pool Geyser movie ( 1.8 Mb, 10 sec, sound).

A movie showing part of the crater near the rear ( east side ) falling into the pool Erosion Movie (0.3 Mb, 1 sec, sound).

All images except deep drain copyright 1998, Michael Frazier. Deep drain copyright 1998, Mas Hayakawa. All rights reserved.