STRUKTUR DIAPIR BAWAH PERMUKAAN DASAR LAUT DI KAWASAN PESISIR SELATAN KABUPATEN SAMPANG-PAMEKASAN, JAWA TIMUR
Abstract
Penelitian seismik pantul dangkal saluran tunggal (seismic profiling) dilakukan di lepas pantai Kabupaten Sampang dan Pamekasan, pesisir selatan Madura dengan hasil rekaman sepanjang 300 km. Interpretasi data seismik dilakukan dengan cara memisahkan runtunan-runtunan yang diduga mempunyai karakter yang berbeda serta mencirikan urut-urutan pengendapan batuan sedimen.
Ciri dari runtunan Kuarter ditandai dengan sedimen yang mempunyai runtunan yang tidak terganggu oleh aktivitas struktur geologi seperti perlipatan maupun pensesaran. Runtunan Tersier dicirikan dengan adanya aktivitas struktur lipatan sangat ketat seperti antiklin, sinklin, dibarengi dengan sesar-sesar, serta intrusi-intrusi diapir.
Data interpretasi seismik pantul dangkal saluran tunggal memberikan gambaran tentang struktur geologi bawah dasar laut walaupun dengan penetrasi yang sangat terbatas (dangkal). Data tersebut juga memberikan gambaran serta indikasi adanya jebakan-jebakan gas bumi dan diapir di kawasan pantai Kabupaten Pemekasan dan Sampang.
Kata Kunci : seismik, runtunan, diapir, Sampang dan Pamekasan
Single channel seismic profiling activity carried out in the southern coast of Pamekasan and Sampang District, southern coast of Madura, has recorded data of more or less 300 kilometres. The interpretation of seismic profiling records have been done by separating the sequence of sediments which have chronologically different character and depositional environments.
The characteristic of Quaternary sediment sequence is indicated by the sediment that did not disturbed by geological structures, such as folding and faulting. The Tertiary sediment sequences in the south coast of Pamekasan area have been tightly folded which consist of anticline, sincline shale diapir and faulting phenomena.
The interpretation of seismic profiling data showed the indication of the geological structure under the sea floor although by means of the shallow penetration energy. It still can be helpful to indicate diapire and gas closures in the southern coast of Sampang and Pamekasan areas.
Key words : seismic, sequence, diapire, Sampang and Pamekasan
Ciri dari runtunan Kuarter ditandai dengan sedimen yang mempunyai runtunan yang tidak terganggu oleh aktivitas struktur geologi seperti perlipatan maupun pensesaran. Runtunan Tersier dicirikan dengan adanya aktivitas struktur lipatan sangat ketat seperti antiklin, sinklin, dibarengi dengan sesar-sesar, serta intrusi-intrusi diapir.
Data interpretasi seismik pantul dangkal saluran tunggal memberikan gambaran tentang struktur geologi bawah dasar laut walaupun dengan penetrasi yang sangat terbatas (dangkal). Data tersebut juga memberikan gambaran serta indikasi adanya jebakan-jebakan gas bumi dan diapir di kawasan pantai Kabupaten Pemekasan dan Sampang.
Kata Kunci : seismik, runtunan, diapir, Sampang dan Pamekasan
Single channel seismic profiling activity carried out in the southern coast of Pamekasan and Sampang District, southern coast of Madura, has recorded data of more or less 300 kilometres. The interpretation of seismic profiling records have been done by separating the sequence of sediments which have chronologically different character and depositional environments.
The characteristic of Quaternary sediment sequence is indicated by the sediment that did not disturbed by geological structures, such as folding and faulting. The Tertiary sediment sequences in the south coast of Pamekasan area have been tightly folded which consist of anticline, sincline shale diapir and faulting phenomena.
The interpretation of seismic profiling data showed the indication of the geological structure under the sea floor although by means of the shallow penetration energy. It still can be helpful to indicate diapire and gas closures in the southern coast of Sampang and Pamekasan areas.
Key words : seismic, sequence, diapire, Sampang and Pamekasan
Full Text:
PDF (Bahasa Indonesia)DOI: http://dx.doi.org/10.32693/jgk.5.1.2007.132