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Kahauale'a II flow moving toward Pahoa again.
#51
This flow seems to stall, then pick up volume and continue. Why does this flow act like this and why has it only put out pahoehoe flows only, is this the norm?. The distance also looks to be short from one end of Pua Farms rd to the flow, but it is longer than it looks. There are a couple trails leading off into that direction but then they seem to veer up towards Eden rock after about 2 or 3 miles. I have had friends that have cut trails most the way out to the flow, and getting back sometimes has been their challenge. I am wondering if we get a trail whacked and fairly strait to this flow if maybe others would want to take the hike?. I know one of the trails gets pretty close already cause the tour copters are overhead and doing large circles. Take plenty of water, boots, machete, and a G.P.S cause its easy to get turned around.
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#52
My husband was curious if there are any tours or ways of getting to the new lava flow. We called a few companies, but they aren't doing any tours. My husband is an avid hiker, and has hiked to the lava on earlier vacations before we moved here. Any suggestions?

Thanks,
Cindy
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#53
Thanks for the very interesting post, pahoated!

Greg
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#54
pretty much the only, and best way, is by helicopter. sure you can hike out there, just like people have hiked to the top of mt everest. it's doable, but it ain't easy.
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#55
Quote:
"the researchers developed a three-dimensional velocity model of a magma anomaly to determine the size, depth and composition of the lava chamber, which is several kilometers in diameter and located at a depth of 8-11 km (5 -- 6.8 miles)."

Being a visual learner, a diagram would help - any available?
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#56
quote:
Originally posted by DoryGray

Quote:


Being a visual learner, a diagram would help - any available?


http://publishing.cdlib.org/ucpressebook...view=print

This might help?
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#57
quote:
Originally posted by ericlp

quote:
Originally posted by DoryGray

Quote:


Being a visual learner, a diagram would help - any available?


http://publishing.cdlib.org/ucpressebook...view=print

This might help?


Brings back memories of my college geology days. Everything was a mathematical formula...
Puna: Our roosters crow first
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#58
Dude, it's a rift zone, not a lava tube.

Here's a simple analogy -
Lava tube is to lava flow as rift zone is to volcano
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#59
quote:
The other finding is that this gigantic magma cavern feeding this continuous flow is pauhoehoe magma, indicating slow oozing for a long time ... unless some kine of blockage or breach occurs.


Magma is magma. There is no "pahoehoe magma," just as there is no a'a magma.

Below is more information regarding the variations in surface lavas.
quote:
http://volcano.oregonstate.edu/what-are-...-they-form

Peterson and Tilling (1980, p. 273) suggested two general conditions that determine whether pahoehoe or aa forms:

If lava slows, cools, and stops in direct response to the corresponding increase in viscosity only, it retains its pahoehoe form.
If lava is forced to continue flowing after a certain critical relationship between viscosity and rate of shear strain is achieved, the lava changes to aa.

Peterson and Tilling called this critical relationship the "transition threshold." They found that if the rate of shear strain is high, the transition threshold is reached at a lower viscosity than if the shear strain rate is low. The converse is also true. If the viscosity of the lava is high, a relatively low rate of shear strain may achieve the transition threshold, and the lava changes to a'a.

People often ask if there is a compositional difference between aa and pahoehoe lava. There is no systematic chemical difference between aa and pahoehoe lava. Lavas with the identical compositions can form both aa and pahoehoe. Lavas that have slight chemical differences tend to have different temperatures and viscosity's but the critical factor influencing the transition from pahoehoe to aa is the viscosity of the lava.


quote:
http://www.geo.cornell.edu/geology/Galap...Types.html

Aa forms when lava flows rapidly. Under these circumstances, there is rapid heat loss and a resulting increase in viscosity. When the solid surface crust is torn by differential flow, the underlying lava is unable to move sufficiently rapidly to heal the tear. Bits of the crust are then tumbled in and coated by still liquid lava, forming the chunks. Sometimes the crust breaks in large plates, forming a platy aa. Pahoehoe forms when lava flows more slowly. Under these circumstances, a well-developed skin can form which inhibits heat loss. When a tear in the skin does form, it is readily healed. Both magma discharge rate and the steepness of the slope over which the lava flows affect the flow rate. Thus aa lavas are associated with high discharge rates and steep slopes while pahoehoe flows are associated with lower discharge rates and gentle slopes. The steep slopes of the large western Galapagos volcanos thus generally consist of aa, making ascent very difficult (and occasionally painful!). The less common pahoehoe flows on these volcanos are erupted from vents on the gently sloping apron or the caldera floor. Flows which begin as pahoehoe can convert to aa when a steep slope is encountered.


quote:
The link below gives a better explanation of the differences in a'a and pahoehoe.

http://hvo.wr.usgs.gov/volcanowatch/arch...05_27.html



"Life is labor, and all that is good in life comes from that labor..."
"Life is labor, and all that is good in life comes from that labor..."
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