Berdasarkan surat perintah No. 1203/P/80, penulis melakukan pemeriksaan dan pengukuran suhu G. Tangkubanparahu.
Sesuai dengan rencana kerja proyek penyelidikan dan pengamatan Gunungapi Direktorat Vulkanologi dalam PELITA III, dilakukan pemeriksaan kegiatan Gunung Lamongan.
On May 18, 1980 after 2 months of local earthquakes and steam eruptions, picturesque Mount St. Helens, a Cascade Range volcano is southwestern Washington, suddenly began a major explosive eruption directed first northward and then upward. The lateral blast, which lasted only the first few minutes of a 9 hour continuous eruption, devastated more than 150 square miles of forest and recreation areā¦