Identifikasi Batupasir Sebagai Zona Prospek Dengan Metode Atribut Seismik Amplitudo RMS

Kemalasari, Vahira Tri (2021) Identifikasi Batupasir Sebagai Zona Prospek Dengan Metode Atribut Seismik Amplitudo RMS. Undergraduate thesis, Institut Teknologi Sepuluh Nopember.

Text 03411740000011-Undergraduate_Thesis.pdf - Accepted Version Restricted to Repository staff only until 1 October 2023. Download (4MB) | Request a copy

Abstract

Penerapan atribut seismik telah banyak dilakukan untuk mengidentifikasi keberadaan struktur, perlapisan, serta litologi berdasarkan jenis atribut yang diterapkan. Amplitudo RMS merupakan salah satu atribut yang dapat membantu menampilkan kontras amplitudo berupa bright spot yang menunjukkan keberadaan litologi batupasir. Penelitian ini bertujuan untuk menentukan lebar jendela amplitudo RMS secara optimum untuk mendapatkan persebaran nilai amplitudo yang selanjutnya dapat digunakan untuk menghitung nilai porositas. Data seismik dengan well diikat dalam well seismic tie, untuk membuat well memiliki domain waktu seperti halnya data seismik. Well seismic tie digunakan untuk membantu picking horizon. Selain well seismic tie, picking horizon dapat dibantu dengan adanya perubahan defleksi dari polaritas pada trace seismik sebagai acuan. Horizon yang dihasilkan berupa 3 (tiga) top lapisan, yakni berupa top lapisan Upper Ngimbang, top Lower Ngimbang, dan Basement. Atribut seismik amplitudo RMS diterapkan melalui setiap penampang line seismik dengan lebar window sebesar 10. Besar lebar window dapat mempengaruhi waktu komputasi serta ketelitian dari hasil kontras amplitudo (bright spot). Amplitudo hasil penerapan atribut seismik diasosiasikan dengan porositas dari log neutron porosity (NPHI). Berdasarkan peta persebaran amplitudo, ditemukan bright spot yang relatif banyak dan jelas pada lapisan Lower Ngimbang. Pada bagian barat yang disebut dengan zona 1, memiliki kontras amplitudo antara 5000–11000 dengan nilai porositas 6,0–9,6 %. Zona 1 memiliki litologi penyusun berupa batugamping yang belum mengalami kompaksi dengan baik. Dan zona 2 terletak pada bagian timur, memiliki kontras amplitudo antara 400–9500 dengan nilai porositas 5,0–9,0 % yang terdiri dari litologi penyusun berupa litologi batupasir.
=====================================================================================================
The application of seismic attributes has been widely carried out to identify structures, layers, and lithology based on the type of attributes applied. RMS- amplitude is one of the attributes that can help display the amplitude contrast (bright spots) which indicate the presence of sandstone. The optimum RMS amplitude window obtain the distribution of the amplitude value which can then be used to calculate the porosity value, that brings this research goal to. Seismic and well data are tied in well seismic tie step, to make wells have a time domain that seismic data show. Well seismic tie is used to help picking horizon. In addition to the well seismic tie, picking horizons can be helped by changes of polarity deflection in seismic trace. The resulting horizon is in the form of 3 (three) top layers, the top Upper Ngimbang, the top Lower Ngimbang, and the top Basement. The RMS amplitude is applied through each section of the seismic line with a window width of 10. The window width can affect the computation time and accuracy of the amplitude contrast results (bright spot). The amplitude resulting from the application of seismic attributes is related to the porosity of the neutron porosity log (NPHI). Based on amplitude distribution map, it was found that there were relatively many bright spots in the Lower Ngimbang layer. In the west part, which is called zone 1, has an amplitude contrast of 5000–11000 with a porosity value of 6,0–9,6%. Zone 1 has a constituent lithology in the form of limestone that has not been well compacted. And zone 2 is in east part, has an amplitude contrast of 4000-9500 with a porosity value of 5,0-9,0% consisting of the constituent lithology in the form of sandstone lithology.

Item Type:	Thesis (Undergraduate)
Uncontrolled Keywords:	Amplitudo RMS, Batupasir, Bright Spot, Porositas, Porosity, RMS Amplitude, Sandstone
Subjects:	Q Science > QE Geology > QE471 Sedimentary rocks. Sedimentology Q Science > QE Geology > QE539.2.S4 Seismic models
Divisions:	Faculty of Civil, Planning, and Geo Engineering (CIVPLAN) > Geophysics Engineering > 33201-(S1) Undergraduate Thesis
Depositing User:	Vahira Tri Kemalasari
Date Deposited:	25 Aug 2021 05:59
Last Modified:	25 Aug 2021 05:59
URI:	http://repository.its.ac.id/id/eprint/89646

Actions (login required)

View Item