Belajar dari tiga kasus : Danau Bandung Purba, Danau Toba, Danau Anak Laut. Secara geologi, air danau bisa menyusut karena : 1. air danau di tempat dalam menemukan formasi batuan yang bisa dikikis sehingga membentuk gua, ke situlah air danau mengalir dan menyusutkan volumenya (kasus air Sungai Citarum purba mengerosi formasi batugamping di Sanghyang Tikoro) 2. air danau kawah Gnapi Toba. Terjadi reaktivasi sesar2 di bawah kawah Gnapi Toba. Gerak reaktivasi sesar2 ini bisa membuka wilayah tension yang kemudian membimbing air untuk memasukinya sehingga air di permukaan menyusut. 3. danau yang secara tektonik terhubung ke retak2 kecil (fisures) yang dibangkitkan gempa, seperti Danau Anak Laut, sangat mungkin menjadi konduit buat air danau menyelinap ke situ dan menyusutkan air di permukaan. Jadi, kondisi stratigrafi batuan penyusun danau, struktur geologi, dan seismo-tektonik (Kuarter)danau akan menjadi kunci ke mana hilangnya air danau. salam, awang
Aria Anugraha <[EMAIL PROTECTED]> wrote: Salam Semuanya, Bicara danau yang menyusut. Ketika saya mewakili IAGI untuk berbicara mengenai data spasial di Sabang - Aceh. Disana juga ada danau namanya D. Anak Laut yang airnya merosot drastis, terutama setelah kejadian Gempa dan Tsunami. Aparat pemda juga menanyakan perihal kemerosotan muka air tersebut. Selama 3 bulan terakhir kurang lebih muka air danaunya turun sekitar 3-4 meteran. Saat ini Danau tersebut digunakan sebagai sumber air bersih untuk seluruh P. Weh. Mungkin para ekspert disini bisa bantu menjelaskan. Wassalam, Aria ----- Original Message ----- From: "R.P. Koesoemadinata" To: Sent: Monday, May 23, 2005 2:31 PM Subject: Re: [iagi-net-l] Hilangnya sebuah Danau > Yang perlu diwaspadai adalah Danau Toba, data menunjukkan muka airnya > turun terus tanpa diketahui sebabnya. > > ----- Original Message ----- > From: > To: > Sent: Monday, May 23, 2005 7:44 PM > Subject: Re: [iagi-net-l] Hilangnya sebuah Danau > > >> >> Bukannya sudah pernah terjadi Mas Jossy. >> Danau Bandung purba dgn Sanghyang Tikoro-nya >> >> salam >> >> Ferry Hakim >> >> >> >> >> "Jossy C. >> Inaray" To: >> >> l.com> Subject: [iagi-net-l] >> Hilangnya sebuah Danau >> >> 05/23/2005 >> 07:49 AM >> Please respond >> to iagi-net >> >> >> >> >> >> >> Ada artikel menarik untuk disimak. Danau2 di jawa barat bisa nggak >> seperti ini? Bisa2 jadi tambahan bencana. >> >> MOSCOW (Reuters) - A Russian village was left baffled Thursday after its >> lake disappeared overnight. >> NTV television showed pictures of a giant muddy hole bathed in summer >> sun, while fishermen from the village of Bolotnikovo looked on >> disconsolately. >> >> "It is very dangerous. If a person had been in this disaster, he would >> have had almost no chance of survival. The trees flew downwards, under >> the ground," said Dmitry Zaitsev, a local Emergencies Ministry official >> interviewed by the channel. >> >> Officials in Nizhegorodskaya region, on the Volga river east of Moscow, >> said water in the lake might have been sucked down into an underground >> water-course or cave system, but some villagers had more sinister >> explanations. >> >> "I am thinking, well, America has finally got to us," said one old >> woman, as she sat on the ground outside her house. >> >> >> JCI >> >> >> --------------------------------------------------------------------- >> To unsubscribe, send email to: [EMAIL PROTECTED] >> To subscribe, send email to: [EMAIL PROTECTED] >> Visit IAGI Website: http://iagi.or.id >> IAGI-net Archive 1: http://www.mail-archive.com/iagi-net%40iagi.or.id/ >> IAGI-net Archive 2: http://groups.yahoo.com/group/iagi >> Komisi Sedimentologi (FOSI) : Deddy >> Sebayang([EMAIL PROTECTED])-http://fosi.iagi.or.id >> Komisi SDM/Pendidikan : Edy Sunardi([EMAIL PROTECTED]) >> Komisi Karst : Hanang Samodra([EMAIL PROTECTED]) >> Komisi Sertifikasi : M. Suryowibowo([EMAIL PROTECTED]) >> Komisi OTODA : Ridwan Djamaluddin([EMAIL PROTECTED] atau >> [EMAIL PROTECTED]), >> Arif Zardi Dahlius([EMAIL PROTECTED]) >> Komisi Database Geologi : Aria A. Mulhadiono([EMAIL PROTECTED]) >> --------------------------------------------------------------------- >> >> >> >> >> >> >> --------------------------------------------------------------------- >> To unsubscribe, send email to: [EMAIL PROTECTED] >> To subscribe, send email to: [EMAIL PROTECTED] >> Visit IAGI Website: http://iagi.or.id >> IAGI-net Archive 1: http://www.mail-archive.com/iagi-net%40iagi.or.id/ >> IAGI-net Archive 2: http://groups.yahoo.com/group/iagi >> Komisi Sedimentologi (FOSI) : Deddy >> Sebayang([EMAIL PROTECTED])-http://fosi.iagi.or.id >> Komisi SDM/Pendidikan : Edy Sunardi([EMAIL PROTECTED]) >> Komisi Karst : Hanang Samodra([EMAIL PROTECTED]) >> Komisi Sertifikasi : M. Suryowibowo([EMAIL PROTECTED]) >> Komisi OTODA : Ridwan Djamaluddin([EMAIL PROTECTED] atau >> [EMAIL PROTECTED]), Arif Zardi Dahlius([EMAIL PROTECTED]) >> Komisi Database Geologi : Aria A. Mulhadiono([EMAIL PROTECTED]) >> --------------------------------------------------------------------- >> > > > --------------------------------------------------------------------- > To unsubscribe, send email to: [EMAIL PROTECTED] > To subscribe, send email to: [EMAIL PROTECTED] > Visit IAGI Website: http://iagi.or.id > IAGI-net Archive 1: http://www.mail-archive.com/iagi-net%40iagi.or.id/ > IAGI-net Archive 2: http://groups.yahoo.com/group/iagi > Komisi Sedimentologi (FOSI) : Deddy > Sebayang([EMAIL PROTECTED])-http://fosi.iagi.or.id > Komisi SDM/Pendidikan : Edy Sunardi([EMAIL PROTECTED]) > Komisi Karst : Hanang Samodra([EMAIL PROTECTED]) > Komisi Sertifikasi : M. Suryowibowo([EMAIL PROTECTED]) > Komisi OTODA : Ridwan Djamaluddin([EMAIL PROTECTED] atau > [EMAIL PROTECTED]), Arif Zardi Dahlius([EMAIL PROTECTED]) > Komisi Database Geologi : Aria A. Mulhadiono([EMAIL PROTECTED]) > --------------------------------------------------------------------- > > > -- > No virus found in this incoming message. > Checked by AVG Anti-Virus. > Version: 7.0.322 / Virus Database: 266.11.15 - Release Date: 5/22/2005 > > --------------------------------------------------------------------- To unsubscribe, send email to: [EMAIL PROTECTED] To subscribe, send email to: [EMAIL PROTECTED] Visit IAGI Website: http://iagi.or.id IAGI-net Archive 1: http://www.mail-archive.com/iagi-net%40iagi.or.id/ IAGI-net Archive 2: http://groups.yahoo.com/group/iagi Komisi Sedimentologi (FOSI) : Deddy Sebayang([EMAIL PROTECTED])-http://fosi.iagi.or.id Komisi SDM/Pendidikan : Edy Sunardi([EMAIL PROTECTED]) Komisi Karst : Hanang Samodra([EMAIL PROTECTED]) Komisi Sertifikasi : M. Suryowibowo([EMAIL PROTECTED]) Komisi OTODA : Ridwan Djamaluddin([EMAIL PROTECTED] atau [EMAIL PROTECTED]), Arif Zardi Dahlius([EMAIL PROTECTED]) Komisi Database Geologi : Aria A. Mulhadiono([EMAIL PROTECTED]) --------------------------------------------------------------------- __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
