Phenomena which would indicate on an increased activity on the Kelut were not observed during 1924 and in the beginning of 1925. A fow light earthshocks, which were felt in the lowercamp, appeared to be of tectonic origin.
Although several times from the surroundings of the Lamongan nevs arrived on eruptions of the volcano, after further investigation appeared, that the observed abnormal phonomena are not to be ascribed to volcanic activity.
Of more importance than the flank eruptions are the excentric eruptions, which are fed from a much more deeper lavaniveau than the first mentioned, whereas the breakthrough mostly takes place in the area of the volcano foot. Also excentric eruptions may entirely independently become active fron the main crater, which at flankeruptions is not likely possible. Also the phenomena, with which excen…
At the end of February 1920 by the Sectionhead of the Irrigation at Lumajang was reported, that in that month an abnormal drop of the waterlevel of the Ranu's Klakah and Pakis had taken place. If the Ranu Klakah in normal times always flowed through his nator al outlet, at present it is not like this, as the lake level has drop till 1.5 m below the outlet This even happens during the full W …
As already earlier mentioned the G. Herapi exists of two morphologic clearly to be distinguished parts, an older eastern and a younger western part. From the sunnit of the old ringdike, only a small part remains (see portrait 14), of which the eastern part is named G. Pusunglondon (2694.3 a.s.) and the northern G. Paseban (2679= a.s.). The old volcano mantle of the G. Merapi has grown much more…
The spreading of the Herapi products is of a great agrogeologic Importance, as the Merapi products compared with the rocks of other Java volcanoes are extraordinary fosforrich. Only towards one side these products could develop feely, namely in the plane of Solo, whare they border to that of the Lavu. To the S the spreading was stopped by the southern mountains, only in the area of the kali Opa…
On October 12, 1920 the inhabitants of the most high laying kampungs in the vicinity of the Blongkengravine were surprised by hot dustclouds and were killed by the burns. It appeared inmediately, that there was no outburst at all, as the summit slopes of the Merapi were, as far as they were overgrown in August and September, were still green as before (the reports from news papers concerning th…
Still a single word on the built up of the volcano as appears from the exposures out side the crater. In all ravines visited by the author, this are the lahar Badak, the lahar Siwalan, the Kali Ijir and the lahar ligobo, the number of lava out flows was not to be called a few. On portrait 17 we see more of such andesite break-through exposed in the ravine of the lahar Ngobo. Remarkable is the f…
The history of the outburst of the Kelut is very monotonous. Each eruption has caused Lahans and these mudheaps always Tork retains, desa's destroyed and in the last time also planta terms.
When we venture a calculation of the amount of the ejected ash and punice, then it goes without saying, that we can only estimate. The statements concerning the amount of the fallen-down ash, are mostly inaccurate and incomplete. Moreover, when we are willing to fix the correct amount of ash, we ought to know the specific gravity and to take into account the thickness of the locally fallen ash …