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<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>Fan and Mortar
erupted at 2330 on 7/31/10. Below are the details of the event cycle
leading up to the eruption.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>I arrived at Fan and
Mortar at around 2130. Paul had been on watch for the past 3 hours and Fan
and Mortar cycles had been in garbage mode, with Angle Vent spurting between
cycles. When I arrived the vents were in the middle of a normal
cycle. After the cycle ended my attention was diverted by an approaching
storm, but the weather passed to the north so I decided to stay on watch a
little longer.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>I noticed the first
huff in Main Vent at 2235. It is possible it could have started huffing a
few minutes earlier since I had been watching the storm, but my
recollection is that the area was pretty quiet beforehand with only the
noise of the wind in the trees catching my attention.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>I had two
flashlights with me: one maglite and another small light that was much dimmer
but did not pick up as much steam. Using both lights I continued to see
and hear Main Vent huff for the next 10 minutes but I was never able to see
any water splashing out of Main. At that time Bottom Vent was splashing
periodically but not erupting.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>At 2245 there was a
shift in wind direction with the steam blowing directly towards me: it was very
difficult to see what was happening with the vents but River Vent was obviously
on and I could still hear Main Vent huffing.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>Sometime before 2300
River Vent quit: I don't have an exact time since I was scrambling around
to get out of the steam. But by 2300 the wind had shifted away from the
benches and I was once again able to see the vents. River Vent was
obviously off, and at 2300 Main Vent gave a huge splash of water that my
maglite was finally able to illuminate. Bottom Vent was also in eruption
at that time, and I estimate its duration was about 5
minutes.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>River Vent came back
on sometime between 2303 and 2305. After that the events were much easier
to see, with the wind continuing to blow away from the benches. Below
is the full set of event cycle times:</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2235: Main
Vent roar</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2245: Main
Vent continued to roar, River Vent in eruption</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>sometime before
2300: River Vent quit. RIVER PAUSE</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2300: Main
Vent huge splash, Bottom Vent in eruption</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>sometime between
2303 and 2305: River Vent on</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2311: Gold
Vent on</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2313: Angle
Vent on</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2315: water
levels look excellent</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2321:
lock</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2329: thick
water surging in Main Vent</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2330:
eruption, Main Vent start</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2344: first
pause</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>2346: eruption
continues</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>0003: last
water</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>0005: last
steam huffs</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>The eruption was
Mortar dominant. Paul, Linda, and Kevin arrived before the lock and
supplied an additional maglite. We had one maglite illuminate Fan and the
other on Mortar. The moon was not yet up, so it was very dark, but the
wind continued to cooperate and the steam blew to the west. We were able
to watch the entire eruption on the jugwalk without getting very wet.
Fan's first surge went over the jugwalk but not much farther beyond; the area
beyond the jugwalk stayed fairly dry. Mortar's water was easier to see
than Fan's. My impression of Fan was watching the very top of the water
column cascading down. It was too steamy to see the base of Fan's vents
for the first part of the eruption.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>Ten minutes into the
eruption, the moon rose and aided us in watching the end of the eruption.
Darren Rose arrived about 6 minutes into the eruption and was still able to see
good water out of Mortar. Nobody else made it down to see the
eruption. After the storm passed it was a very nice evening and not too
cold.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=861455914-02082010>It was nice having
closure to the end of our vacation. We were able to leave the Park on
Sunday morning without worrying about missing Fan and Mortar. Here's
hoping the next eruption is in daylight with lots of gazers
there!</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=861455914-02082010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><FONT face="Times New Roman" size=3><SPAN
class=861455914-02082010></SPAN></FONT>S<SPAN class=861455914-02082010>uzanne
Strasser</SPAN><BR></DIV></FONT></BODY></HTML>