You are probably too young to know this, but in the late 60’s there was a cheesy movie by the title “Krakatoa, East of Java”. Just comes to show how little Hollywood knows about world geography because Karakatoa (or what is left of it) is actually west of Java.
So we landed in Jakarta early in the morning, where we were once received by our friends of BMKG. This time Mr. Sandy was going to be our host, and half an hour later we were driving through the heavy morning traffic west, bound for the northwest corner of Java, 100 km away. Once there we found yet another ignimbrite, yet another caldera (this time without an intracaldera lake), and a thriving industrial complex with sand mines (the ignimbrite), two cement factories, three steel mills, and several modern petrochemical factories. I think in this case Indonesia has taken to heart the use of its main port on the Sunda Strait to create a major industrial and economic hub.
Pushing a bit to the south along the shore we arrived at the tourist enclave of Anyer, right across the Sunda Strait from the famed Krakatoa. Krakatoa was a volcanic island, like so many andesitic stratovolcanoes that had grown out of the water, and in 1883 had a big Plinian eruption that evacuated a significant amount of dacitic magma from its shallow magma chamber. The volume extracted was enough to cause the collapse of the roof of the chamber, just like it happened in Crater Lake in Oregon. But this time the collapse (and total disappearance out of sight of the island volcano) caused a sudden change in the volume of the surrounding ocean and a big tsunami wave. The tsunami flooded the west coast of Java and the east coast of Sumatra, causing great destruction. The Dutch Postmaster General, father of the famous Dutch geologist van Belemmnen, did a sterling job at documenting the devastation, and in some way became “the Father” of western tsunami science.
In the decades that followed post-caldera volcanism caused several new Krakatoa small vents to peek out of the water, which eventually resolved on the formation of Anak Krakatoa (the son of Krakatoa), which is slowly growing and surviving wave erosion by consistent Strombolian eruptions. Anak Krakatoa is a dangerous child, a bit like Ronnie, so it bears careful observation. For example, in 2018 the flank of the young volcano collapsed without any significant warning and caused a moderately destructive tsunami. Anyway, we came here to visit the Krakatoa Volcano Observatory, where we found an IT young man in residence, who was all too happy to have someone to talk with and to display reams and reams of hard-copy seismograph records (I am sure they are also in the computer, but hard-copy is more impressive). Unfortunately the atmosphere is hazy, so we couldn’t get a sight of the troubled child.
I briefly considered renting a boat (about 4,000,000 rupiah), but learnt that I could not pay with credit card. Bad tourism preparedness, for how am I going to come with 4,000,000 rupiah cash when all the stupid ATM’s will give me is 1,000,000 per day?
We are spending the night at a modest but very charming tourist hotel by the shore, and tomorrow morning will go back to Jakarta for a couple of days.
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