CD-ROM Aktief 1995 #3/CDA3.iso/survival/95eqca12.zip/HVO---12.RPT

Text File | 1995-03-27 | 4KB | 97 lines

Offline Xpress Message Folder File - Created on 1995-03-27

|OLX$SOM|
BBS: CDMG
Conference: 84,UN_Geology
Number: 1620
Reply-to: 0
Private: No
Receipt: No
ExHeader: YES
Date: 1995-03-23,16:14
From: [e-mail] (Gerard Fryer)
To: ALL
Subject: HVO Volcano Watch - 19 Ma
Flags:

From: [e-mail] (Gerard Fryer)
This is the 19 March issue of Volcano Watch from the Hawaiian Volcano
Observatory. It is a description of current eruption and flow status of
Kilauea Volcano. An accompanying figure - a map of the latest flows -
will be posted to sci.geo.geology.

Volcano Watch is available via WWW at the following URL:

http://www.soest.hawaii.edu/hvo/

Note that while this post comes from the University of Hawai`i at
Manoa, Volcano Watch itself originates at USGS's Hawaiian Volcano
Observatory.

-----------------------------------------------------
Hawaiian Volcano Observatory
P.O. Box 51
Hawaii National Park, Hawaii 96718
tel. [phone]             fax [phone]

Volcano Watch--March 19, 1994

Kilauea's 12-year-old East Rift Zone eruption continues with lava
issuing from vents on the southwest flank of Pu'u 'O'o. Since December,
the eastern and western boundaries of the Kamoamoa- Lae'apuki flowfield
have expanded, and much of the area in between has been resurfaced with
new lava. During most of this time, there were four concurrent ocean
entries across a three kilometer stretch of coastline. A new 'a'a flow
to the west of the main flow field broke out at the 2,100 foot
elevation on February 10 and reached Paliuli in four days. The upper
reaches of the flow roofed over, and the new tube fed a rapidly
spreading pahoehoe sheet on the coastal plain that burned grasslands
and set off methane explosions as it advanced.  This flow was within
150 meters of Chain of Craters Road before the front stagnated on
February 27. As of a week ago, activity on this flow had ceased, but
not before archeological sites in the Mo'olehua area (near Paliuli)
were partially buried by lava.

The western portion of the main flowfield continues to consume the end
of Chain of Craters Road and is advancing westward a few hundred meters
mauka of the road. This flow has joined the westernmost flow to form
the 'Mo'olehua Kipuka. Lava is entering the ocean at a point very close
to the High Castle overlook, providing spectacular lava viewing at the
end of the road.

The extensive surface-flow activity described above has been ongoing
since October. This is in contrast to most of 1994, when lava was
efficiently transported from the vents directly to the ocean in a
well-developed (mature) lava tube system. The change in behavior is a
result of the three brief pauses in the eruption that occurred in
October and November. After each pause, the lava tube system was
reoccupied only from the vent to the top of Pulama Pali. The top of the
pali is always a weak spot in the tube system because of the abrupt
change in slope. Following each pause, the lava broke out at this
point, and new surface flows advanced down the pali. Since the last
pause at the end of November, a mature tube system has not had time to
develop within the new surface flows.

Below the 1,900 foot elevation, two new lava tubes are currently
feeding lava to ocean entries on the eastern and western sides of the
Kamoamoa lava delta.  The volume of lava actually entering the ocean is
still relatively small, because surface flows are widespread on the
coastal plain. If the eruption continues without a pause, mature tube
systems may develop on either the Laeapuki or the Kamoamoa side of the
flowfield, or both.

During the last few days, we observed signs of a 'slow down' in
eruptive activity. The amount of lava issuing from the vents decreased
significantly between Tuesday and Friday. At the same time, the summit
of Kilauea inflated, and the number of shallow summit earthquakes
increased. Taken together, these observations indicate that the magma
reservoir beneath the summit was filling and that less lava was
reaching the East Rift Zone eruption site. On Friday, the ocean entries
were dead, but large `a`a flows were advancing down Pulama Pali,
suggesting that the eruption volume was back to normal. As always, it's
a good idea to call the National Park Service for an eruption update
before you embark on a lava- viewing excursion.

---