Shiretokoiozan Excursion Guide To the Crater One (Explosion Crater)
It is appropriate to visit Shiretokoiozan during the summer because during
the winter and early spring and late fall, it is extremely cold and snowy.
The Road etween Shiretoko Goko Lake Gate and Kamuiwakka Bus Stop is restricted
some period during the summer, so you must check it befor visiting there.
You would visit Kamuiwakka Bus Stop either by bus or rental car.
It would take one hour and a half to the Crater One from Kamuiwakka and
it is extremely hot during the summer. So I recommend you to bring two
litters of water with you.
*The Crater One is called "Explosion Crater" by geologists but
here I would like to use old name given by miners "The Crater One."
Point A:
When you get off the bus, you would see the bulletin board like the phtograph
above. Open the box on the bulletin board. There are some pieces of paper
in it. They are forms you must fill in to walk the 500-meters road ahead
to the starting point of the mountain trail.
The form is written in only Japanese language. I wrote the example in red
ink above. So just fill in and post it to the post box on the right.
The local government says this 500-meters road ahead between Kamuiwakka
Bus Stop and the Starting point of Mountain Trail is dangerous to walk
due to falling rocks. This is the application of permission to walk on
the road ahead. When you post the form, then you are permitted. Easy.
It is safe enough. Japanese public governments like regulations.
After you post the document to the box, you can just walk between the gate
and the fence beside and walk for 500 meters to the start of the trail.
Point B:
Right before you arrive at the mountain trail, watch out to the Okhotsk
Sea. You would find yellow to white mud in the blue water. I am not sure
what it is but it is said small particle of sulfur is floating. (I don't
think so)
Point C:
This is the start of mountain trail to the summit of Shiretokoiozan though
we will climb up to the Crater One just a quarter of the whole way to the
summit. You might see some bears in the trail. I recommend you to carry
a bell with you. You can rent a counter bear spray at Shiretoko Nature
Center but I do not think it is necessary. I have one but have never used
it.
At the beginning the trail goes very steep slope for about fifty meters
and when you finished climbing the hard slope there is a sign. The trail
turns right there then you might find the trail goes leftward too. From
this point we will walk on an old path which sulfur miners used. The old
trail, which is not used now, goes down to the cliff on the sea.
Point D:
Walking for 40 or 50 minutes you will be reach at a platform with no trees
above. You could outlook for Kamuiwakka Creek and summit area of Shiretokoiozan.
Let us look down the deep creek, Kamuiwakka. You might see steam coming
up from some parts in the creek. Very acid hot spring water flow s down
in this creek. All the water in this creek is hot spring.
In 1936 the Crater One, where we will see later, eruppted 200,000 tons
of molten sulfur and the brown liquid flowed into this Kamuiwakka Creek
and fulfilled. You can see no sulfur today because the sulfur was mined
for gun powder after the eruption.
You can see "Sulfur Falls" from the outlook site. Dr. Watanabe
who took this photograph wrote in his article that the molten sulfur falled
with thundering roar.
The trail goes through low pine bushes. You might see the outcrop in this
photograph. It is a section of large sheet lava of andesite. This volcano
composed of many andesite lava sheet like this photograph.
Point E:
For ten or twenty minutes walk you will see a artificial rock wall. A platform
with big hole is above the wall. This is a ruin of old sulfur mine. Still
it smells sulfur gas here.
Point F:
The trail goes in Kakosawa Dry Creek. The creek, where molten sulfur flowed
at 1936-eruption, is full of huge rocks. You can find small pieces of sulfur
on the rock surface. The creek was full of sulfur during that days. Still
some sulfur remains here.
Some pieces of sulfur has small cavities. The molten sulfur contained volcanic
gas in it and when it cooled and solidified, the gas made bubbles and they
became cavities. However the sulfur piece in this photograph does not have
cavities.
When you complete climbing the huge rocks and artificial stone wall, you
will see rocky bare hill. This no-tree area is called "Shinfunkako"
by mountain climbers. Due to acid poisonous volcanic gas and geothermal
heat, trees cannot grow but only small bushes can live.
You can see the summit of 1562 meters Shiretokoiozan and on the left there
is a white wall made of sand and clay. The sulfur eruption crater, the
Crater One is located just behind this white wall.
The mountain trail goes along Kakonosawa Cry Creek on the right showed
in the photograph above.
As this old photograph shows you, molten sulfur flowed in this creek in 1936. Still you can find some pieces of sulfur in the creek. Watch closely. It has cavities and small rock pieces in it.
Point G:
The trail goes through a pink clay area. The path is very slippy and many
mountain climbers have slipped to fall here.
Let's touch on the ground. It is warm. Due to the heat sometimes snakes
sleep here.
Point H:
You will see a sunken ground forward called "Ohiroma." I guess
it is a pit crater which ground subsided. Duirng the erupiton in 1936,
Ohiroma was filled with sulfur like the photgraph above.
Let us proceed along the trail and after walking for around 50 meters from
Ohiroma, you will see a steep slope with white gravels on your left. Climb
up the gravel slope some how. The Crater One is above this white gravel
slope.
The white gravels were altered by volcanic gas and heat. colorred minerals
decayed and outflowed from the rock and white minerals and clay remained.
Those white rocks are fragile and light.
The Crater One is over the top of the while gravel hill.
Point I:
Now we have arrived at the Crater One.
There are several fumarole puffing volcanic gas in the crater. The volcanic
gas contains toxic hydrogen sulfide and water vapor. You smell boiling
egg: it is hydrogen sulfide. The concentration of the hydrogen sulfide
of a fumarole is around 10,000 ppm (Sept. 13, 2014). If you inhaled 1000
ppm of hydrogen sulfide, one thenth of the concentration, you might die
right away. But fortunately western part of the crater is open and strong
wind comes through, you do not have to worry about the toxic gas so much.
When you are close to fumaroles, just hold your breath.
I will continue writing later.
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