Ahmat Dafit Hasim Asrori | Institut Teknologi Sepuluh Nopember (original) (raw)
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Model kecepatan dalam proses pengolahan data seismik merupakan aspek penting yang perlu diperhati... more Model kecepatan dalam proses pengolahan data seismik merupakan aspek penting yang perlu diperhatikan. Model kecepatan seismik ini diperlukan dalam proses migrasi untuk merubah data seismik terekam menjadi gambar struktur bawah permukaan, oleh karena itu model kecepatan seismik sangat menentukan kualitas penampang seismik hasil pengolahan. Model kecepatan ini tidak bisa didapatkan langsung dari akusisi data di lapangan sehingga diperlukan metode tertentu untuk mendapatkannya. Pada penelitian ini dilakukan penentuan model kecepatan dalam domain kedalaman menggunakan inversi tomografi dari atribut gelombang normal incident point kinematik dari proses CRS. Penelitian dimulai dengan pencarian atribut kinematik untuk mendapatkan stack CRS dengan parameter terbaik. Dari data CRS stack tersebut ditentukan informasi mengenai waktu tempuh gelombang normal, lokasi kemunculan sinar, turunan spasial pertama dari waktu tempuh atau perlambatan, dan turunan spasial kedua dari waktu tempuh sesuai dengan posisi reflektor. Keempat informasi tersebut direkonstruksi dengan pemodelan inversi untuk mendapatkan model kecepatan bawah permukaan untuk kemudian dilakukan migrasi pada domian kedalaman. Selain itu pada penelitian ini juga dilakukan analisa kecepatan seperti metode konvensional pada umumnya dan kemudian dibandingkan hasilnya. Hasil yang didapat memperlihatkan penampang stack CRS memiliki kemenerusan reflektor yang baik dan jumlah artefak yang sedikit dibandingkan penampang stack konvensional. Proses inversi tomografi dilakukan dengan 13 kali iterasi untuk mendapatkan nilai eror terkecil yaitu sebesar 0.034. Model kecepatan hasil dari proses inversi tomografi setelah dilakukan migrasi dalam domain kedalaman memiliki hasil penampang yang lebih jelas dan memiliki reflektor yang lebih menerus dibuktikan dengan gather seismic yang lebih flat dan eror residu yang lebih mendekati nol jika dibandingkan dengan penampang migrasi menggunakan model kecepatan dari proses konvensional.
Kata kunci : Migrasi domain kedalaman, Common Reflection Surface, Inversi tomografi, atribut kinematic CRS.
In Indonesia, most of oil and gas reservoir are sandstone reservoirs, along with the human needs ... more In Indonesia, most of oil and gas reservoir are sandstone reservoirs, along with the human needs of energy, another concept of reservoir must be developed to find new source of oil and gas. Nowadays, there is an issue that productivity of sandstone reservoir has been decreased. So, people try to look for another concept of petroleum exploration (carbonate reservoir). Therefore, the development of new methods for the characterization of reservoir sandstone is required. Generally, AVO (Amplitude Versus Offset) method is used to characterize the reservoir sandstone. In this research, the method which is used to characterize reservoir sandstones is seismic multi attribute methods. Currently, the seismic multi attributes analysis is commonly used at the interpretation stage. Seismic attributes are defined by Brown (2000) as a derivative of the basic seismic measurements. The characterization results are obtained from analysis of the seismic multi-attributes that describe the improvement of imaging the reservoir sandstone’s quality characterization. Then the calculations of seismic multi-attributes are used as input Probabilistic Neural Network (PNN) calculation of data log. The results of PNN transformation then was distributed as a non-linear equation solution. From the results of this study, found that PNN can characterize the geologic conditions from upper sands reservoir, by the value of analysis 0.72 as a correlation from data log. The impacts of this research can be used for hydrocarbon exploration and development activities of the target field.
Keywords: Development, Sandstone, Multi-Attribute, Probabilistic Neural Network
Data quality is an important factor in the 2D and 3D seismic method, seismic data interpretation ... more Data quality is an important factor in the 2D and 3D seismic method, seismic data interpretation process will depend on the quality of the data processing is done, one of the factors is a seismic resolution, seismic resolution is the ability of seismic data to separate two thin layers are adjacent. This research was conducted on the improvement of resolution of seismic data or better known as Enhancement Seismic spectral decomposition method of either Resolution with continuous wavelet transform, The variation of frequency used and the wavlet. wavlet type used is the morlet and Gaussian frequency variation used 30 Hz, 40 Hz, 50 Hz, 60 Hz, 70Hz, and 80Hz. from the results obtained with great frequency the greater seismic resolution also Appears on the frequency 80Hz is most obvious on the horizon. And the wavlet best used Gaussian type wavelet is due more to increase the resolution of significant seismic
Key words: seismic resolution Enhancement, soectral decomposition, wavlet morlet, wavlet gaussian.
Suramadu bridge linking surabaya with madura island. Because of the very vital role performed me... more Suramadu bridge linking surabaya with madura island. Because of the very vital role
performed measurements to determine the characteristics of a bridge being built in an area of
alluvial deposits and minimize the possibility in case of very high amplification. Surabaya is the
dominant lowland areas with geological conditions 80% of alluvial deposits. Development of
infrastructure in earthquake resistant should be qualified, to minimize the risk of loss and
accidents arising as a result of the occurrence of an earthquake. One of the important factors
that can be used to predict the danger of earthquakes on buildings was done between the
resonance frequency measurement of natural building and the land underneath it. If the value of
frequency the frequency value approaching natural building material underneath it, the seismic
vibrations will create a resonance with the building that will increase the stress on the building.
Mikrotremor analysis conducted at the Suramadu bridge aims to determine the value of the
natural frequency of bridge, determines the resonance of the bridge and land against waves of
the earthquake as well as to determine the level of vulnerability of a bridge against a wave of
earthquakes.Natural frequency analysis of the resulting data structure component of the NS
ranged from 2.64 - 3.44 Hz and EW 2.66 - 3.92 Hz and the frequency of natural ground ranges
from 1.86 - 3.15 Hz and the RDM component of the NS ranged 0.73 - 66 Hz and EW
components 1.71 - 51.4 Hz. Suramadu bridge belongs to already meet the standard of bridge
damping ratio and natural frequency. Most high vulnerability index value is located in the central
part of the bridge. So the middle part of the bridge is the bridge pillars is the weakest parts in
case of an earthquake
Keyword : Mikrotremor, FSR , RDM , ground Resonance
Dosen Pendamping Bidang Kemahasiswaan iii KATA PENGANTAR Indonesia merupakan negeri dengan berbag... more Dosen Pendamping Bidang Kemahasiswaan iii KATA PENGANTAR Indonesia merupakan negeri dengan berbagai kekayaan yang melimpah namun juga negeri dengan berbagai potensi bencana di dalamnya termasuk gempa bumi dan juga tanah longsor. Tentunya solusi apapun sangat diperlukan untuk menanggulangi permasalahan tersebut mulai dari sebelum ataupun setelah bencana gempa atau longsor terjadi.Karya Tulis ini menyuguhkan salah satu alternatif solusi sekunder lewat ilmu pengetahuan dan juga teknologi untuk menyelesaikan permasalahan gempa bumi maupun tanah longsor di indonesia. Puji serta syukur penulis panjatkan kepada Tuhan YME yang telah memberikan rahmat dan hidayah-Nya sehingga penulis mampu menyelesaikan penyusunan Karya Tulis Ilmiah yang berjudul MIKROTREMOR SOLUSI DAERAH RAWAN GEMPA DAN LONGSOR .tentunya Karya Tulis Ilmiah ini masih banyak kekurangannya baik dalam hal penulisan maupun pemilihan kata kata sehingga saran dan kritik yang membangun dari pembaca sangat penulis perlukan sebagai bahan perbaikan. iv
Model kecepatan dalam proses pengolahan data seismik merupakan aspek penting yang perlu diperhati... more Model kecepatan dalam proses pengolahan data seismik merupakan aspek penting yang perlu diperhatikan. Model kecepatan seismik ini diperlukan dalam proses migrasi untuk merubah data seismik terekam menjadi gambar struktur bawah permukaan, oleh karena itu model kecepatan seismik sangat menentukan kualitas penampang seismik hasil pengolahan. Model kecepatan ini tidak bisa didapatkan langsung dari akusisi data di lapangan sehingga diperlukan metode tertentu untuk mendapatkannya. Pada penelitian ini dilakukan penentuan model kecepatan dalam domain kedalaman menggunakan inversi tomografi dari atribut gelombang normal incident point kinematik dari proses CRS. Penelitian dimulai dengan pencarian atribut kinematik untuk mendapatkan stack CRS dengan parameter terbaik. Dari data CRS stack tersebut ditentukan informasi mengenai waktu tempuh gelombang normal, lokasi kemunculan sinar, turunan spasial pertama dari waktu tempuh atau perlambatan, dan turunan spasial kedua dari waktu tempuh sesuai dengan posisi reflektor. Keempat informasi tersebut direkonstruksi dengan pemodelan inversi untuk mendapatkan model kecepatan bawah permukaan untuk kemudian dilakukan migrasi pada domian kedalaman. Selain itu pada penelitian ini juga dilakukan analisa kecepatan seperti metode konvensional pada umumnya dan kemudian dibandingkan hasilnya. Hasil yang didapat memperlihatkan penampang stack CRS memiliki kemenerusan reflektor yang baik dan jumlah artefak yang sedikit dibandingkan penampang stack konvensional. Proses inversi tomografi dilakukan dengan 13 kali iterasi untuk mendapatkan nilai eror terkecil yaitu sebesar 0.034. Model kecepatan hasil dari proses inversi tomografi setelah dilakukan migrasi dalam domain kedalaman memiliki hasil penampang yang lebih jelas dan memiliki reflektor yang lebih menerus dibuktikan dengan gather seismic yang lebih flat dan eror residu yang lebih mendekati nol jika dibandingkan dengan penampang migrasi menggunakan model kecepatan dari proses konvensional.
Kata kunci : Migrasi domain kedalaman, Common Reflection Surface, Inversi tomografi, atribut kinematic CRS.
In Indonesia, most of oil and gas reservoir are sandstone reservoirs, along with the human needs ... more In Indonesia, most of oil and gas reservoir are sandstone reservoirs, along with the human needs of energy, another concept of reservoir must be developed to find new source of oil and gas. Nowadays, there is an issue that productivity of sandstone reservoir has been decreased. So, people try to look for another concept of petroleum exploration (carbonate reservoir). Therefore, the development of new methods for the characterization of reservoir sandstone is required. Generally, AVO (Amplitude Versus Offset) method is used to characterize the reservoir sandstone. In this research, the method which is used to characterize reservoir sandstones is seismic multi attribute methods. Currently, the seismic multi attributes analysis is commonly used at the interpretation stage. Seismic attributes are defined by Brown (2000) as a derivative of the basic seismic measurements. The characterization results are obtained from analysis of the seismic multi-attributes that describe the improvement of imaging the reservoir sandstone’s quality characterization. Then the calculations of seismic multi-attributes are used as input Probabilistic Neural Network (PNN) calculation of data log. The results of PNN transformation then was distributed as a non-linear equation solution. From the results of this study, found that PNN can characterize the geologic conditions from upper sands reservoir, by the value of analysis 0.72 as a correlation from data log. The impacts of this research can be used for hydrocarbon exploration and development activities of the target field.
Keywords: Development, Sandstone, Multi-Attribute, Probabilistic Neural Network
Data quality is an important factor in the 2D and 3D seismic method, seismic data interpretation ... more Data quality is an important factor in the 2D and 3D seismic method, seismic data interpretation process will depend on the quality of the data processing is done, one of the factors is a seismic resolution, seismic resolution is the ability of seismic data to separate two thin layers are adjacent. This research was conducted on the improvement of resolution of seismic data or better known as Enhancement Seismic spectral decomposition method of either Resolution with continuous wavelet transform, The variation of frequency used and the wavlet. wavlet type used is the morlet and Gaussian frequency variation used 30 Hz, 40 Hz, 50 Hz, 60 Hz, 70Hz, and 80Hz. from the results obtained with great frequency the greater seismic resolution also Appears on the frequency 80Hz is most obvious on the horizon. And the wavlet best used Gaussian type wavelet is due more to increase the resolution of significant seismic
Key words: seismic resolution Enhancement, soectral decomposition, wavlet morlet, wavlet gaussian.
Suramadu bridge linking surabaya with madura island. Because of the very vital role performed me... more Suramadu bridge linking surabaya with madura island. Because of the very vital role
performed measurements to determine the characteristics of a bridge being built in an area of
alluvial deposits and minimize the possibility in case of very high amplification. Surabaya is the
dominant lowland areas with geological conditions 80% of alluvial deposits. Development of
infrastructure in earthquake resistant should be qualified, to minimize the risk of loss and
accidents arising as a result of the occurrence of an earthquake. One of the important factors
that can be used to predict the danger of earthquakes on buildings was done between the
resonance frequency measurement of natural building and the land underneath it. If the value of
frequency the frequency value approaching natural building material underneath it, the seismic
vibrations will create a resonance with the building that will increase the stress on the building.
Mikrotremor analysis conducted at the Suramadu bridge aims to determine the value of the
natural frequency of bridge, determines the resonance of the bridge and land against waves of
the earthquake as well as to determine the level of vulnerability of a bridge against a wave of
earthquakes.Natural frequency analysis of the resulting data structure component of the NS
ranged from 2.64 - 3.44 Hz and EW 2.66 - 3.92 Hz and the frequency of natural ground ranges
from 1.86 - 3.15 Hz and the RDM component of the NS ranged 0.73 - 66 Hz and EW
components 1.71 - 51.4 Hz. Suramadu bridge belongs to already meet the standard of bridge
damping ratio and natural frequency. Most high vulnerability index value is located in the central
part of the bridge. So the middle part of the bridge is the bridge pillars is the weakest parts in
case of an earthquake
Keyword : Mikrotremor, FSR , RDM , ground Resonance
Dosen Pendamping Bidang Kemahasiswaan iii KATA PENGANTAR Indonesia merupakan negeri dengan berbag... more Dosen Pendamping Bidang Kemahasiswaan iii KATA PENGANTAR Indonesia merupakan negeri dengan berbagai kekayaan yang melimpah namun juga negeri dengan berbagai potensi bencana di dalamnya termasuk gempa bumi dan juga tanah longsor. Tentunya solusi apapun sangat diperlukan untuk menanggulangi permasalahan tersebut mulai dari sebelum ataupun setelah bencana gempa atau longsor terjadi.Karya Tulis ini menyuguhkan salah satu alternatif solusi sekunder lewat ilmu pengetahuan dan juga teknologi untuk menyelesaikan permasalahan gempa bumi maupun tanah longsor di indonesia. Puji serta syukur penulis panjatkan kepada Tuhan YME yang telah memberikan rahmat dan hidayah-Nya sehingga penulis mampu menyelesaikan penyusunan Karya Tulis Ilmiah yang berjudul MIKROTREMOR SOLUSI DAERAH RAWAN GEMPA DAN LONGSOR .tentunya Karya Tulis Ilmiah ini masih banyak kekurangannya baik dalam hal penulisan maupun pemilihan kata kata sehingga saran dan kritik yang membangun dari pembaca sangat penulis perlukan sebagai bahan perbaikan. iv