Mount Poco Leok is one of the volcanoes on the island of Flores that left only traces after the catastrophic eruption 15 thousand years ago to form a caldera. But the limits of the calendar are not clear. Post-formation of the caldera, inside lava domes are formed which is now known as Poco (top) Mandosawu and Ranakah. Volcanic activity then seems to stop completely since the formation of the lava domes, which lasted for 15 thousand years later. During that period the Poco Leok caldera region transformed into a lush and calm forest. Tranquility was disturbed on December 28, 1987 when shocks and explosions shook the region. The explosion was centered from the northeastern slopes of Poco Ranakah, at an elongated crevice known to locals as loka leke ndereng (red shell hole). During the next week of this crack exit water vapor and volcanic ash vertically, characteristic of phreatic eruption (eruption due to underground water interaction with magma so that water turns into steam pressurized). Until January 3, 1988 there were 17 times high-pressure eruption and 200 times low-pressure eruption.…
East Nusa Tenggara
City / Regency
Kabupaten Manggarai Timur
1.1 Kecamatan Wae Rii
2.1 Kecamatan Poco Ranaka; 2.2 Kecamatan Borong
1.1.1 Desa Ranaka
2.1.1 Desa Golo Lobos
2.2.1 Desa Sano Lokom; 2.2.2 Desa Golo Loni
a vulcano / active
History of eruption;
Volcano volcanic activity is interesting since the birth of Mount Anak Ranakah which started by the eruption that occurred on December 28, 1987. Before this eruption, there is no historical record of eruption activity. The eruption that occurred on 28 December 1987 was a phreatic eruption that was preceded by an earthquake tremor and was followed by a cloud of smoke that reached a height of between 3,000 and 4,000 meters above the point of eruption, the thickest ash of the eruption was deposited around the eruption hole and spread eastward to the Rana Mese about 3 km from the eruption hole. This initial eruption penetrates the rock cover so as to give way for the escape of magma up the surface. As of January 3, 1988 there have been 17 strong eruptions and 200 weak eruptions.
On January 9, 1988 seen a fairly bright ray of fire, this shows the existence of magma that rises the surface of the earth through the hole eruption, on January 10, 1988 the lava dome of Mount Anak Ranakah can be seen with a clear gray blackish. On January 11, 1988 a major eruption with a smoke altitude of about 8,000 m accompanied by a glide of hot clouds to Wae Reno and Wae Teko north of the volcano. On 17 January 1988, the lava dome already has a height of 100 m with a long tongue lavanya in the river Wae Reno about 600 m. The result of volcanology team measurement on 21 january 1988, lava dome has volume 5 million m3, while the volume of all eruption of Mount Anak Ranakah is about 9 million m3. In August 1988 the volume of lava dome reached 18.8 million m3. Due to the destabilization caused by gravity and also the impetus of the magma movement from inside the volcano’s stomach causes the visible frequent avalanches and followed by the formation of hot clouds flowing into Wae Reno and Wae Teko; triggered by the existence of rain at that time, volcanic material pile has formed lava flows, the lava flow that formed this crashed and destroyed Wae Teko and Wae Reno bridge.…
Elevation (meters above sea level);
2,350 m (7,710 ft)
Type of eruption;
Anak Ranakah volcano is the youngest active volcano in Indonesia, erupted on December 28, 1987, its birth was very shocking experts kegunungapian at that time, because previously there was no record of the history of the eruption. The eruption period is unknown, because the first known eruption was only in 1987 and to date it has not erupted yet, until now the Anak Ranakah mountain has never experienced an increase in activity. Based on seismic data, rarely recorded earthquakes, both tectonic earthquakes and volcanic earthquakes.
Topology & Geology;
GunungAnak Ranakah terletak di lereng utara dan merupakan bagian dari rangkaian kubah lava yang berjejer konsentris disekitar kaldera gunungapi purba Pocok Leok, Gunung Anak Ranakah merupakan kubah lava termuda. Batuan komplek Gunung Ranakah didominasi oleh lava, sebagian kecil awanpanas dan guguran vulkanik, sedangkan Gunung Anak Ranakah berbentuk kubah lava. Sumber magma komplek Gunung Ranakah adalah dangkal dan batuannya berupa andesit dari seri alkalikapur. Kubah Gunung Anak Ranakah dipermukaannya berupa bongkah-bongkah besar, mempunyai warna abu-abu, pada akhir tahun 1988 terlihat kepulan asap yang sangat lemah keluar dari beberapa bagian kubah. Berdasarkan hasil analisa umur batuan berdasarkan charcoal radiocarbon dating dari endapan awan panas yang ada di komplek gunung Ranakah diperoleh umur 14.570 +320 tahun.
Umumnya lava-lava komplek Gunung Ranakah telah mengalami ubahan/alterasi dengan derajat ubahan yang bervariasi. Secara petrografis, berdasarkan tekstur dan komposisi mineraloginya, batuan kompleks Gunung Ranakah dapat dikelompokkan menjadi:
Kementerian Energi dan Sumber Daya Mineral, Badan Geologi (Link; drive.google.com)
Characteristic of geothermal fluid at East Manggarai, Flores, East Nusa Tenggara: Mochamad Iqbal, Geological Engineering, Bandung Institute of Technology; Niniek Rina Herdianita, Applied Geology Research Group, Bandung Institute of Technology; Dikdik Risdianto, Center for Geological Resources, Bandung; (Link; drive.google.com)
Vulkanisme dan prakiraan bahaya Gunung Api Anak Ranakah, Nusa Tenggara Timur; Deden Wahyudin, Badan Geologi; Jurnal Lingkungan dan Bencana Geologi, Vol. 3 No. 2 Agustus 2012: 89-108 (Link; drive.google.com)