Artikel Ilmiah : H1F009017 a.n. BISMA SALIMUDIN
| NIM | H1F009017 |
|---|---|
| Namamhs | BISMA SALIMUDIN |
| Judul Artikel | GEOLOGI DAN STUDI FASIES TURBIDIT SATUAN BATUPASIR-BATULEMPUNG FORMASI PENOSOGAN DAERAH KAJORAN DAN SEKITARNYA KECAMATAN KARANGGAYAM KABUPATEN KEBUMEN |
| Abstrak (Bhs. Indonesia) | Jawa Tengah termasuk daerah yang sangat penting dari batuan dasar yang diketahui di jawa, dikenal sebagai kompleks Luk Ulo (Van Bemmelen 1949; asikin et al., 1992; dalam Clement, 2009). Ini dianggap sebagai produk imbrikasi dari perubahan kapur saat batas subduksi meluas dari Jawa Barat, berlanjut ke kompleks Luk Ulo, hingga Pegunungan Meratus. Proses pengangkatan dan perombakan batuan di utara cekungan Karangsambung menjadi sumber utama pengisian cekungan. Satuan breksi basalt-andesit dapat disebandingkan dengan formasi waturanda yang terbentuk pada miosen awal (N4-N8; Blow, 1969) di kedalaman 200-800 meter (Batial atas-batial tengah) oleh mekanisme aliran butir (grain flow) dan aliran pecahan (debris flow). Dengan terjadinya genang laut, material yang diendapkan merupakan material yang relatif lebih halus, terbentuklah Satuan batupasir-batulempung di daerah Kajoran dan sekitarnya. Setelah dilakukan pengukuran penampang stratigrafi dan identifikasi batuannya, satuan ini dapat disebandingkan dengan formasi penosogan pada miosen tengah (N9-N14; Blow, 1969) di lingkungan pengendapan Neritik luar sampai Batial atas (150-350 mdpl) melalui mekanisme aliran pecahan (debris flow), arus turbid densitas tinggi, atau arus turbid densitas rendah. Didasarkan pada Bouma (2000) dan Walker (1999), di daerah Karanggayam-Kajoran tersingkap batuan dengan fasies turbidit yang lengkap. Namun didasarkan pada Shanmugam (2006) fasies turbidit ini dianggap sebagai turbidit tidak lengkap. Peningkatan aktifitas tektonik menyebabkan peningkatan aktifitas vulkanisme dan menghasilkan satuan batupasir yang dapat disebandingkan dengan formasi halang, terbentuk pada miosen akhir sampai pliosen awal (N17-N20) di lingkungan kedalaman 30-200 mdpl dengan mekanisme debris flow atau arus turbid densitas tinggi. Hampir bersamaan dengan pembentukan satuan batupasir, Dengan sumber yang diduga berbeda terbentuk satuan breksi andesit menjari dengan satuan batupasir pada kisaran umur pliosen awal (N18-N20) di lingkungan neritik luar hingga batial atas (100-450 mdpl) melalui mekanisme aliran butir (grain flow) dan aliran pecahan (debris flow). Setelah pengendapan satuan batuan, peningkatan aktifitas tektonik pada pliosen-pleistosen juga berpengaruh besar dalam deformasi dan penyesaran batuan (Sesar Karanggayam). |
| Abtrak (Bhs. Inggris) | Central Java includes the most extensive area of basement rocks known in Java, the Luk Ulo Complex (van Bemmelen 1949; Asikin et al. 1992; Clement 2009). This is usually regarded as the imbricated product of Cretaceous deformation at a subduction margin that extended from West Java, through the Luk Ulo Complex, to the Meratus Mountains. Northward thrusting, deformation and weathering was the main sources of feeding basin. Basalt-Andesitic Breccia can comparable with Waturanda Formation which formed since lower Miocene (N.4-N.8; Blow 1969) at 200-800 m (upper bathyal-middle bathyal) by grain flow or debris flow mechanism. Transgression was consist in west, and the material be finer then the sandstone-mudstone was formed in Kajoran and arounded area. After measuring section and identification the lithology, it can comparable with Penosogan Formation while sedimentation begin at middle Miocene (N.9-N.14; Blow 1969) in outer neritic to upper bathyal (150-350) by debris flow, high-density turbidity current or low-density turbidity current. It is the comprehensive turbidites in Bouma (2000) and Walker (1999), but in Shanmugam (2006) this unit was incomplete turbidity facies. Increase of tectonic activity cause increase volcanism activity and result sandstone unit which can comparable with Halang Formation. It is formed in 30-200 m deep inner shelf to outer shelf at upper Miocene to lower Pliocene (N.17-N.20), by debris flow or high density turbidity current. From the other source, formed andesitic breccia unit in outer shelf to upper bathyal (100-450 m) at lower Pliocene (N.18-N.20), by grain flow or debris flow mechanism. Increase of tectonic activity influence the basin and form the deformation of basin, deposit and thrust fault (Karanggayam fault). GEOLOGY AND STUDY TURBIDITY FACIES OF SANDSTONE-MUDSTONE UNIT OF PENOSOGAN FORMATION IN KAJORAN AND AROUNDED OF SUBDISTRICT KARANGGAYAM KEBUMEN REGENCY Central Java includes the most extensive area of basement rocks known in Java, the Luk Ulo Complex (van Bemmelen 1949; Asikin et al. 1992; Clement 2009). This is usually regarded as the imbricated product of Cretaceous deformation at a subduction margin that extended from West Java, through the Luk Ulo Complex, to the Meratus Mountains. Northward thrusting, deformation and weathering was the main sources of feeding basin. Basalt-Andesitic Breccia can comparable with Waturanda Formation which formed since lower Miocene (N.4-N.8; Blow 1969) at 200-800 m (upper bathyal-middle bathyal) by grain flow or debris flow mechanism. Transgression was consist in west, and the material be finer then the sandstone-mudstone was formed in Kajoran and arounded area. After measuring section and identification the lithology, it can comparable with Penosogan Formation while sedimentation begin at middle Miocene (N.9-N.14; Blow 1969) in outer neritic to upper bathyal (150-350) by debris flow, high-density turbidity current or low-density turbidity current. It is the comprehensive turbidites in Bouma (2000) and Walker (1999), but in Shanmugam (2006) this unit was incomplete turbidity facies. Increase of tectonic activity cause increase volcanism activity and result sandstone unit which can comparable with Halang Formation. It is formed in 30-200 m deep inner shelf to outer shelf at upper Miocene to lower Pliocene (N.17-N.20), by debris flow or high density turbidity current. From the other source, formed andesitic breccia unit in outer shelf to upper bathyal (100-450 m) at lower Pliocene (N.18-N.20), by grain flow or debris flow mechanism. Increase of tectonic activity influence the basin and form the deformation of basin, deposit and thrust fault (Karanggayam fault). |
| Kata kunci | Turbidit, fasies, aliran, sesar, bouma |
| Pembimbing 1 | Eko Bayu Purwasatriya, S.T., M.Si. |
| Pembimbing 2 | Asmoro Widagdo, ST., MT. |
| Pembimbing 3 | |
| Tahun | 2015 |
| Jumlah Halaman | 27 |
| Tgl. Entri | 2015-08-09 16:33:42.046583 |