Garuda - Garba Rujukan Digital

Article Per Year (5 Year)

All

BULLETIN OF THE MARINE GEOLOGY

bomg
Website

Published by Marine Geological Institute of Indonesia

ISSN : 14106175 EISSN : 25278843 DOI : -

Core Subject : Science,

Earth & Planetary Sciences

Bulletin of the Marine Geology is a scientific journal of Marine geoscience that is published periodically, twice a year (June and December). The publication identification could be recognized on the ISSN 1410-6175 (print) and e-ISSN: 2527-8843 (on-line) twice a year (June & December) and it has been accredited by Lembaga Ilmu Pengetahuan Indonesia (Indonesian Institute of Sciences) by Decree Number: 818/E/2015. As an open access journal, thus all content are freely available without any charge to the user. Users are allowed to download, and distribute the full texts of the articles without permission from the publisher.

Arjuna Subject : -

Articles 5 Documents

Search results for , issue "Vol 30, No 1 (2015)" : 5 Documents clear

SEAFLOOR FAULTING AND ITS RELATION TO SUBMARINE VOLCANIC ACTIVITIES BASED ON SUB BOTTOM PROFILING (SBP) ANALYSES IN WEH ISLAND WATERS AND ITS SURROUNDING, NANGROE ACEH DARUSSALAM PROVINCE Hananto Kurnio; Ildrem Syafri; Adjat Sudradjat; Mega Fatimah Rosana; Dicky Muslim
BULLETIN OF THE MARINE GEOLOGY Vol 30, No 1 (2015)
Publisher : Marine Geological Institute of Indonesia

Sub bottom Profiling survey using strata box, a specially designed low penetration sub bottom Profiling (< 80 m) for coastal waters exploration, found out evidence of submarine volcanic activities in northern coastal waters of Weh Island, NanggroeAceh Darussalam Province. Gas bubbling could be observed at water columns of the digital sub bottom Profiling records as acoustic turbidity. There are at least 33 spots of volcanic gas bursts observed from the sub bottom Profiling. Examination of gas bursts at coastal area which show fumaroles and solfatara indicate reduce volcanic activity either at submarine or terrestrial. Identification of seafloor gas burst by diving team found out that center of such burst is occurred at a north - south opened lineation assumed as normal fault. It seems that the seafloor normal fault is the continuation of terrestrial fault of the same direction as observed from terrain earth google of Weh Island.Keywords: seafloor faulting, submarine volcanic activities, shallow sub bottom Profiling data, Weh Island Aceh Survei penampang bawah dasar laut (SBP) menggunakan strata box, suatu alat SBP penetrasi rendah yang didisain untuk eksplorasi perairan pantai, mendapatkan bukti-bukti aktivitas gunungapi bawah laut di perairan sebelah utara Pulau Weh, Provinsi Nanggroe Aceh Darussalam. Gelembung-gelembung gas dapat diamati pada kolom air rekaman digital penampang bawah dasar laut sebagai turbiditas akustik. Sedikitnya dijumpai 33 titik semburan gas volkanik yang teramati dari penampang bawah dasar laut tersebut. Pemeriksaan semburan-semburan gas pada wilayah pantai sebagai fumarola dan solfataramenunjukkan telah berkurangnya aktivitas volkanik apakah pada dasar laut maupun darat. Identifikasi semburan gas dasar laut oleh tim selam mendapatkan bahwa pusat semburan berada pada kelurusan berarah utara - selatan yang diduga sebagai sesar normal. Tampaknya adalah bahwa sesar normal dasar laut tersebut merupakan kelanjutan sesar darat yang berorientasi sama seperti teramati dari citra earthgoogle terrain Pulau Weh. Kata kunci: pensesaran dasar laut, aktivitas gunungapi bawah laut, data penampang bawah dasar laut, Pulau Weh Aceh

MARINE GEOLOGICAL AND HYDRO OCEANOGRAPHIC DATA FOR SITE SEAPORT LOCATION SELECTION AT SAMPIT BAY AND ITS SURROUNDING, EAST KOTAWARINGIN, CENTRAL KALIMANTAN I Wayan Lugra
BULLETIN OF THE MARINE GEOLOGY Vol 30, No 1 (2015)
Publisher : Marine Geological Institute of Indonesia

Sampit Bay is one of many main gates to enter the Central Kalimantan Province, because there is Mentaya River Mouth as an access to the Sampit Harbour as a main port at its province. Until now, the Sampit Bay only used as anchored for big ships waiting turn to enter Sampit Port. The methods used are coastal characteristic mapping, seafloor surficial sediment sampling, grain size analyses, echosounding, and current measurement. Sampit bay has sandy coast, sand of sea floor surficial sediment, and gradation of sea floor morphology which is suitable for sea port location. On the other hand, the velocity of the surface and midle current in the bay ranging between 0.1-0.3 m/second which is dominated by south east direction. The mentioned velocity is under threshold for safety ship anchoraged. Beside that, most of the bay open to the wind from west and south west facing Java Sea, where the velocity ranging from 5-13 m/second which is included into weak catagories. Location is recommended to be sea port candidate in the south of Ujung Pandaran.Keywords: Sampit Bay, port location, coastal characteritistic, sea floor surficial sediment, current velocity. Teluk Sampit adalah salah satu gerbang utama memasuki Propinsi Kalimantan Tengah, karena tempat bermuaranya Sungai Mentaya yang merupakan akses menuju ke pelabuhan Sampit sebagai pelabuhan utama di provinsi tersebut. Selama ini teluk Sampit hanya digunakan sebagai tempat lego jangkar kapal-kapal besar yang menunggu giliran untuk berlabuh di Pelabuhan Sampit. Metode yang digunakan adalah pemetaan karakteristik pantai, pengambilan contoh sedimen permukaan dasar laut, analisis besar butir, pemeruman, dan pengukuran arus. Teluk Sampit memiliki jenis pantai berpasir dan sedimen permukaan dasar laut pasir serta morfologi dasar laut yang bergradasi cukup layak untuk lokasi pelabuhan. Disamping itu kecepatan arus permukaan dan menengah di teluk tersebut berkisar antara 0,1-0,3 meter/detik dengan arah dominan ke arah tenggara, dimana kecepatan arus tersebut masih dibawah ambang batas untuk keamanan kapal berlabuh. Disamping itu, sebagian besar teluk tersebut terbuka terhadap hembusan angin arah barat dan tenggara yang berhadapan dengan laut Jawa dimana kecepatan angin yang bertiup antara 5-13 meter/detik dan termasuk dalam katagori lemah. Lokasi yang paling layak untuk lokasi pelabuhan adalah sebelah selatan Ujung Banaran. Kata kunci: Teluk Sampit, lokasi pelabuhan, karakteristik pantai, sedimen permukaan dasar laut, kecepatan arus.

HYDROTHERMAL MINERALIZATION IN JAILOLO WATERS, WEST HALMAHERA, NORTH MALUKU PROVINCE Lili Sarmili
BULLETIN OF THE MARINE GEOLOGY Vol 30, No 1 (2015)
Publisher : Marine Geological Institute of Indonesia

Halmahera Island tectonically is divided into two main regimes, those are East Arm Regime (EAR) and West Arm Regime (WAR). Both regimes have very different characteristics where the EAR consists of Cretaceous ultramafic rocks and old red shale, while the WAR composed of Neogene sediment. The study area is an area with active tectonism shown by recent seismic activities and volcanic eruptions. Hydrothermal activity is indicated by rocks alteration of andesite, dacite, and diorite such as kaolinite, argilic and montmorilonite. Primary metal type mineralization occured in a strong altered volcanic rocks, while the secondary mineralization occured in the sedimentary placer. AAS, petrographic analysis, and mineralografi obtained mineral pyrite, manganese, chalcopyrite in rocks from coastal and marine offshore up to depth of 100 meters. Analysis of the 36 examples of seabed sediments, showed the presence of anomalous metal minerals of Au, Cu, Mn, and Fe those are content of Au 0.01 - 0.03 ppm; Cu 14-150 ppm; Mn 23-1050 ppm; and Fe 2-10%.Keywords: Jailolo waters, western arm regime (WAR), andesite, dacite and diorite intrusion rocks, mineralization of Au, Cu, Mn, and Fe. Pulau Halmahera tektonik dibagi menjadi dua rezim utama, yaitu East Arm Rezim (EAR) dan Westt Arm Rezim (WAR). Kedua rezim memiliki karakteristik yang sangat berbeda yang EAR terdiri dari batuan ultrabasa Kapur dan shale merah tua, sedangkan WAR Terdiri dari batuan sedimen berumur Neogen. Daerah penelitian sebagai daerah dengan tektonik dan vulkanik aktif yang ditunjukan dengan aktifitas gempa dan letusan gunungapi hingga sekarang. Aktifitas hidrothermal ditunjukkan oleh alterasi pada batuan andesit, dasit, dan diorite. Mineral ubahan yang terbentuk kaolinit, argilik dan montmorilonit. Tipe mineralisasi logam primer terdapat dalam batuan vulkanik terubah kuat, sedangkan mineralisasi sekunder terdapat dalam sedimen plaser. Hasil analisis AAS, petrografi, dan mineralografi didapatkan mineral pirit, mangan, kalkopirit pada batuan di pesisir dan laut lepas hingga kedalaman 100 meter. Hasil analisis terhadap 36 sedimen dasar laut, menunjukan adanya kandungan mineral logam Au,Cu, Mn, dan Fe dengan kadar Au=0.01 - 0,03 ppm; Cu 14-150 ppm; Mn 23-1050 ppm; dan Fe 2-10% . Kata kunci: Mandala lengan barat (MLB), batuan intrusi andesit, dasit, dan diorit, mineralisasi Au, Cu, Mn, dan Fe, Perairan Jailolo, Halmahera Barat.

THE GEOCHEMICAL CHARACTERISTIC OF MAJOR ELEMENT OF GRANITOID OF NATUNA, SINGKEP, BANGKA AND SIBOLGA Ediar Usman
BULLETIN OF THE MARINE GEOLOGY Vol 30, No 1 (2015)
Publisher : Marine Geological Institute of Indonesia

A study of geochemical characteristic of major elelemnt of granitoid in Western Indonesia Region was carried out at Natuna, Bangka, Singkep and Sibolga. The SiO2 contents of the granites are 71.16 to 73.02 wt%, 71.77 to 75.56wt% and 71.16 to 73.02wt% at Natuna, Bangka, and Singkep respectively, which are classified as acid magma. While in Sibolga the SiO2 content from 60.27 to 71.44wt%, which is classified as intermediate to acid magma. Based on Harker Diagram, the granites from Natuna, Bangka and Singkep as a co-genetic. In other hand the Sibolga Granite show as a scatter pattern. Granites of Natuna, Bangka and Singkep have the alkaline-total (Na2O + K2O) between 6.03 to 8.51 wt% which are classified as granite and alkali granite regime. K2O content ranges from 3.49 to 5.34 wt% and can be classified as calc-alkaline type. The content of alkaline-total of Sibolga granite between 8.12 to 11.81 wt% and classified as a regime of syenite and granite. The range of K2O is about 5.36 to 6.94wt%, and assumed derived from high-K magma to ultra-potassic types. Granites of Natuna, Bangka and Singkep derived from the plutonic rock types and calc-alkaline magma, while Sibolga granite magma derived from K-high to ultra-potassic as a granite of islands arc. Based on the chemical composition of granite in Western Indonesian Region can be divided into two groups, namely Sibolga granite group is representing the Sumatera Island influenced by tectonic arc system of Sumatera Island. Granites of Bangka and Singkep are representing a granite belt in Western Indonesian Region waters which is influenced by tectonic of back arc.Keywords: magma, geochemical characteristic, major element and Western Indonesian Region Kajian karakteristik geokimia dari unsur utama granitoid di Kawasan Barat Indonesia telah dilakukan di daerah Natuna, Bangka, Singkep dan Sibolga. Kandungan SiO2 granit Natuna antara 71,16 - 73,02%, Bangka antara 71,77 - 75,56%, Singkep antara 72,68 - 76,81% termasuk dalam magma asam. Granit Sibolga memiliki kandungan SiO2 antara 60,27 - 71,44% termasuk dalam magma menengah - asam. Berdasarkan Diagram Harker, granit Natuna, Bangka dan Singkep mempunyai asal kejadian yang sama (ko-genetik), sedangkan granit Sibolga membentuk pola pencar. Granit Natuna, Bangka dan Singkep mengandung total alkalin (K2O+Na2O) antara 6,03 - 8,51% termasuk dalam jenis rejim granit dan alkali granit. Berdasarkan kandungan K2O antara 3,49 - 5,34 %berat, bersifat kalk-alkali. Granit Sibolga mengandung total alkali antara 8,12 - 11,81% termasuk dalam rejim syenit dan granit, dan berdasarkan kandungan K2O antara 5,36 - 6,94% berasal dari jenis magma K-tinggi sampai ultra-potassik. Granit Natuna, Bangka dan Singkep berasal dari jenis batuan beku dalam dan magma kalk-alkalin yang berhubungan dengan penunjaman, sedangkan granit Sibolga berasal dari jenis magma K-tinggi - ultra-potassik sebagai granit busur kepulauan. Berdasarkan komposisi unsur kimia utama, granit di Kawasan Barat Indonesia dapat dibagi dalam dua, yaitu granit Sibolga yang mewakili P. Sumatera, dipengaruhi oleh sistem tektonik busur P. Sumatera. Granit Bangka dan Singkep dapat mewakili suatu jalur granit di perairan Kawasan Barat Indonesia yang dipengaruhi oleh tektonik busur belakang. Kata kunci: jenis magma, karakteristik geokimia, unsur utama, dan Kawasan Barat Indonesia

THE EXISTENCE OF COASTAL FOREST, ITS IMPLICATION FOR TSUNAMI HAZARD PROTECTION, A CASE STUDY: IN CILACAP-CENTRAL JAVA, INDONESIA Yudhicara Yudhicara
BULLETIN OF THE MARINE GEOLOGY Vol 30, No 1 (2015)
Publisher : Marine Geological Institute of Indonesia

The southern coast of Java which is facing to the Indian Ocean has many of natural hazard potential come from the sea. Since 2006 tsunami impacted the southern coast of Java, and caused severely damage especially along the coast of Cilacap (1-7,7 m run up height). People commit to do greening the beach by planting suitable plants such as a Casuarina equisetifolia, Terminalia catappa, and Cocos nucifera. This paper discusses the existence of coastal forests in Cilacap coastal area, their potential ability as a coastal protection from the tsunami wave which cover the density, diameter, height, age, and other parameters that affects the coastal defence against tsunami waves. Some experiences of tsunamis that have occurred, indicating that the above parameters linked to the ability of vegetation to act as a natural barrier against tsunamis. In the case of sandy beaches, such as in Cilacap, Pandanus odorarissimus has more effectiveness than other trees due to its hanging roots that can withstand the tsunami height less than 5 m, able to withstand debris and can withstand the scouring effects of tsunami waves, while Casuarina equisetifolia along Cilacap beaches more dominant than other trees, so it is recommended to increase the diversity of plants as well as increase the density and tree placement setting. By field measurement in order to get parameter applied to some graphs, Cilacap coastal forest does not enough capability for tsunami barrier reflected to the tsunami height experience in this region. Ages could be the important parameter in order to have bigger diameter trunk, higher trees height, and high resistance capacity againts tsunami hazard potential. Compare to Kupang, East Nusa Tenggara, Cilacap coastal forest still young and need some more years to make trees ready act as tsunami reduction. Keywords: Cilacap coastal forest, Kupang, tsunami, vegetation parameters. Pantai Selatan Jawa yang berhadapan dengan Samudera Hindia, memiliki banyak potensi mengalami bahaya yang datang dari lautan. Selama tahun 2006, Tsunami telah menimpa sebagian pantai selatan Jawa dan menyebabkan banyak kerusakan parah terutama di sepanjang Pantai Cilacap (tinggi gelombang 1-7,7 m). Masyarakat melakukan penghijauan pantai dengan menanam sejumlah pohon yang sesuai dengan kondisi pantai, seperti pohon cemara pantai (Casuarina equisetifolia), ketapang (Terminalia cattapa) dan kelapa (Cocos nucifera). Tulisan ini membahas penyebaran hutan pantai di wilayah pantai Cilacap, kemampuan dan potensi hutan tersebut sebagai pelindung alami pantai dari bahaya gelombang tsunami, yang terdiri dari kerapatannya, diameter, tingginya, umur, dan parameter lainnya yang mempengaruhi daya tahan pantai terhadap gelombang tsunami. Beberapa pengalaman mengenai kejadian yang telah terjadi, memperlihatkan bahwa parameter tersebut di atas mempengaruhi kemampuan tanaman sebagai penahan alamiah terhadap tsunami. Untuk kondisi pantai berpasir seperti Cilacap, tanaman pandan pantai lebih efektif dibandingkan dengan tanaman lainnya, dikarenakan akarnya yang dapat menahan tinggi gelombang kurang dari 5 m, selain itu akar tersebut dapat menahan material dan erosi vertikal gelombang tsunami, sementara di sepanjang pantai Cilacap, tanaman cemara pantai (Casuarina equisetifolia) lebih dominan dibandingkan tanaman lainnya. Kondisi ini dapat direkomendasikan untuk tetap dipertahankan bahkan ditambah jumlahnya. Di lapangan dilakukan pengukuran parameter tanaman pantai dan hasilnya diplot dalam bentuk grafik dan diaplikasikan dalam grafik yang dibuat berdasarkan hasil penelitian terhadap tsunami di beberapa tempat di dunia terutama di Jepang. Berdasarkan tinggi gelombang maksimum yang pernah terjadi di daerah ini (7,7 m), terlihat bahwa hutan pantai Cilacap belum cukup mampu bertindak sebagai penahan gelombang tsunami. Umur merupakan parameter penting agar pohon memiliki diameter yang besar, pohon yang cukup tinggi dan daya tahan terhadap potensi bahaya tsunami. Dibandingkan dengan hutan pantai di Kupang, Nusa Tenggara Timur, hutan pantai di Cilacap relatif masih muda dan membutuhkan beberapa tahun lagi untuk dapat memperkecil resiko yang ditimbulkan oleh bahaya tsunami. Kata kunci: Hutan pantai Cilacap, Kupang, tsunami dan parameter vegetasi.

Page 1 of 1 | Total Record : 5

Filter by Year

2015 2015

Filter By Issues

All Issue Vol 40, No 2 (2025) Vol 40, No 1 (2025) Vol 39, No 2 (2024) Vol 39, No 1 (2024) Vol 38, No 2 (2023) Vol 38, No 1 (2023) Vol 37, No 2 (2022) Vol 37, No 1 (2022) Vol 36, No 2 (2021) Vol 36, No 1 (2021) Vol 35, No 2 (2020) Vol 35, No 1 (2020) Vol 34, No 2 (2019) Vol 34, No 1 (2019) Vol 33, No 2 (2018) Vol 33, No 1 (2018) Vol 32, No 2 (2017) Vol 32, No 1 (2017) Vol 31, No 2 (2016) Vol 31, No 1 (2016) Vol 30, No 2 (2015) Vol 30, No 1 (2015) Vol 29, No 2 (2014) Vol 29, No 1 (2014) Vol 28, No 2 (2013) Vol 28, No 1 (2013) Vol 27, No 2 (2012) Vol 27, No 1 (2012) Vol 26, No 2 (2011) Vol 26, No 1 (2011) Vol 25, No 2 (2010) Vol 25, No 1 (2010) Vol 24, No 2 (2009) Vol 24, No 1 (2009) Vol 23, No 1 (2008) Vol 22, No 1 (2007) More Issue

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Unknown,

Unknown

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name -

Contact Email -

Phone -

Journal Mail Official -

Editorial Address -

Location Unknown, Unknown INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Unknown,

Unknown

INDONESIA