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Noor C.d. Aryanto - One of the best experts on this subject based on the ideXlab platform.

  • The Study of Seafloor Tin Placer Resources of Quaternary Sediment at Toboali Waters, South Bangka
    Marine Geological Institute of Indonesia, 2017
    Co-Authors: Zulfikar Muhammad, Noor C.d. Aryanto
    Abstract:

    Bangka Island has primary and secondary tin Deposit. However, along the history of tin mining has been done the primary tin Deposit domination is less than secondary tin Deposit. Secondary tin Deposit is formed from Granitic S-type source rock weathering and then transported by gravity. After that, Cassiterite mineral (SnO2) accumulates and forms a Placer Deposit in the study area. The thickness of sediment cover at Toboali Waters is quite diverse, with a range between 5-20 milliseconds, by knowing the quarter sediment thickness using seismic data interpretation results, is expected to give an idea about tin Placer Deposit potential in Toboali waters. Based on the Isochron map shows patterns of quaternary sediment thickening to the southwest, south and southeast of Bangka Island.Keywords: Quaternary sediment, Placer Deposit, isochron map, Toboali WatersPulau Bangka memiliki endapan timah primer dan endapan timah sekunder. Namun, sepanjang sejarah penambangan timah yang telah dilakukan endapan timah primer tidak mendominasi jika dibandingkan dengan endapan timah sekunder. Pembentukan endapan timah sekunder berawal dari pelapukan batuan Granit tipe-S yang kemudian mengalami transportasi akibat adanya gravitasi. Setelah itu, mineral kasiterit (SnO2) terakumulasi dan membentuk endapan plaser di daerah penelitian. Ketebalan sedimen penutup di Perairan Toboali berkisar antara 5-20 milidetik, dengan mengetahui ketebalan sedimen kuarter berdasarkan interpretasi data hasil rekaman seismik diharapkan dapat memberikan gambaran tentang potensi endapan timah Placer di Perairan Toboali. Berdasarkan atas peta isokron, memperlihatkan bahwa pola penebalan sedimen kuater ke arah baratdaya, selatan dan tenggara Pulau Bangka.Kata kunci : Sedimen kuarter, endapan Placer, peta isokron, Perairan Toboal

  • The Study of Seafloor Tin Placer Resources of Quaternary Sediment at Toboali Waters, South Bangka
    Marine Geological Institute of Indonesia, 2017
    Co-Authors: Muhammad Zulfikar, Noor C.d. Aryanto
    Abstract:

    Bangka Island has primary and secondary tin Deposit. However, along the history of tin mining has been done the primary tin Deposit domination is less than secondary tin Deposit. Secondary tin Deposit is formed from Granitic S-type source rock weathering and then transported by gravity. After that, Cassiterite mineral (SnO2) accumulates and forms a Placer Deposit in the study area. The thickness of sediment cover at Toboali Waters is quite diverse, with a range between 5-20 milliseconds, by knowing the quarter sediment thickness using seismic data interpretation results, is expected to give an idea about tin Placer Deposit potential in Toboali waters. Based on the Isochron map shows patterns of quaternary sediment thickening to the southwest, south and southeast of Bangka Island

  • HEAVY MINERALS IN Placer Deposit IN SINGKAWANG WATERS, WEST Kalimantan, RELATED TO FELSIC SOURCE ROCK OF ITS COASTAL AREA
    BULLETIN OF THE MARINE GEOLOGY, 2016
    Co-Authors: Deny Setiady, Noor C.d. Aryanto
    Abstract:

    Placer Deposits are physically accumulated by fluvial and marine processes in coastal area. Thirty six samples were selected from seventy seven samples of seafloor sediment of Singkawang waters. Those samples have been analyzed microscopically for heavy mineral contents. Based on this analysis, the heavy minerals can be divided into four groups: oxyde and hydroxyde, silicate, sulphide, and carbonate. The source of most heavy minerals in the study area is commonly formed by Felsic igneous rock and finally Deposited on the seafloor sediments. Keywords: heavy minerals, Placer Deposit, felsic igneous rock, Singkawang Endapan letakan secara fisik umumnya terakumulasi oleh proses sungai dan laut. Sebanyak 36 contoh dipilih dari 77 contoh sedimen permukaan dasar laut di Perairan Singkawang. Contoh tersebut telah dilakukan analisis kandungan mineral berat secara mikroskopis. Berdasarkan hasil analisis mineral berat ini dapat dibedakan menjadi empat kelompok yaitu oksida dan hidroksida, silikat, sulfida, dan karbonat. Sebagian besar sumber mineral berat di daerah penelitian pada umumnya berasal dari batuan beku felsik yang akhirnya diendapkan di permukaan dasar laut. Kata kunci: mineral berat, endapan letakan, batuan beku felsik, Singkawang.

Jose Maria Gonzalezjimenez - One of the best experts on this subject based on the ideXlab platform.

  • re os isotopic constraints on the source of platinum group minerals pgms from the vestřev pyrope rich garnet Placer Deposit bohemian massif
    Ore Geology Reviews, 2015
    Co-Authors: Jan Pasava, Jan Malec, W L Griffin, Jose Maria Gonzalezjimenez
    Abstract:

    Abstract Mineralogical studies of the heavy fraction from a Holocene pyrope-rich garnet Placer Deposit at Vestřev (Krkonose Piedmont Basin, Bohemian Massif) have identified the presence of very rare grains of platinum group minerals (PGM). Pt–Fe alloy grains are accompanied by Os–Ir–Ru minerals (native osmium, iridium, and ruthenium) with inclusions of Pt–Fe alloy and hongshiite (PtCu). This mineral assemblage is typical for several mantle settings including ophiolites. The chemistry of the Os–Ir–Ru minerals shows an enrichment of the PGM in Ru, which is typical of ophiolites. The grain morphology of PGM and pyrope-rich garnet (mostly rounded with numerous euhedral/subhedral grains) does not exclude a common source. In-situ laser-ablation MC-ICP-MS was used to measure the Re–Os isotopic compositions of single Os-rich grains, which show heterogeneous subchondritic Os isotopic compositions ( 187 Os/ 188 Os = 0.12082–0.12505 ± 0.00003). This precludes their low-temperature origin and indicates derivation of platinum-group elements (PGEs) essentially from mantle-derived rocks without a significant contribution of crustal Os. The mantle model age (T MA ) and Re-depletion model age (T RD ) model ages range from ~ 0.4 to ~ 1.0 Ga and most likely reflect a long history of melt depletion that affected the mantle sources of PGM.

Michael F. Gazley - One of the best experts on this subject based on the ideXlab platform.

  • Stratigraphy, provenance and localisation of the titanomagnetite Placer at Waikato North Head, South Auckland, New Zealand
    Mineralium Deposita, 2020
    Co-Authors: Robert L. Brathwaite, Anthony B. Christie, Michael F. Gazley
    Abstract:

    The sequence of coastal and river sands of Pleistocene to Holocene age at the north head of the Waikato River is ~80-m thick; the sands are located in a fault-angle depression at the southern end of the Awhitu Peninsula, a 40-km-long coastal sand barrier. The sequence at Waikato North Head (WNH) consists of three main formations: Awhitu Sands, Hood Sands and Mitiwai Sands. The Waiuku Black Sand member of the Hood Sands and the Entrican Sand member of the Mitiwai Sands contain titanomagnetite-rich dune sands, which are currently mined by New Zealand Steel and constitute a giant Placer Deposit that has a total resource of ~90 Mt Fe. A tephra at the top of the Awhitu Sands is correlated with the ~1000 ka Waiuku (Potaka) tephra. The Mitiwai Sands overlie the 1.85 ka Taupo Pumice. Comparison of electron probe microanalyses (EPMA) of titanomagnetites in heavy mineral separates of surface and drill-hole samples indicated that the bulk of the titanomagnetite in the Waiuku Black sand and the Entrican Sand is derived from andesitic rocks of the Taranaki Volcanoes 220 km to the south. The Waiuku Black Sand may correlate with an influx of andesitic clasts and mafic minerals in the cover beds of the ~400 ka Ararata Terrace in south Taranaki. There is also a contribution of titanomagnetite and minor ilmenite from the ignimbrites of the Taupo Volcanic Zone (TVZ), particularly in the Lower Hood and Entrican sands. Automated mineralogy data collected on selected sand samples contain silicate and resistate minerals that indicate other potential sources in addition to the Taranaki andesites and TVZ ignimbrites. Minor olivine was likely derived from the late Pleistocene basalts of the South Auckland volcanic field, whereas almandine and epidote were likely sourced from metasedimentary rocks of the Murihiku and Waipapa terranes. The formation of the giant Placer at WNH was a multistage process involving (1) a supply of titanomagnetite-bearing sand eroded from the late Pleistocene–Holocene andesites of the Taranaki volcanoes that was transported northwards along the coast by the prevailing longshore drift; (2) concentration of titanomagnetite by wave action on beach faces and collection in a coastal embayment on the northern side of a headland of basement rocks at Port Waikato; (3) further concentration by wind action into dune sands during interglacial low sea levels; and (4) preservation by coeval subsidence in a fault-angle depression on the down-thrown north side of the Waikato Fault.

Mustafa, Moch. Akrom - One of the best experts on this subject based on the ideXlab platform.

  • INDIKASI KETERDAPATAN ENDAPAN PLASER PEMBAWA TIMAH DAN UNSUR TANAH JARANG (REE), DI PERAIRAN TODAK, SINGKEP, KEPULAUAN RIAU
    Pusat Penelitian dan Pengembangan Geologi Kelautan, 2016
    Co-Authors: Kamiludin Udaya, Astawa I Nyoman, Mustafa, Moch. Akrom
    Abstract:

    Penelitian geofisika di Perairan Todak, Singkep, Kepulauan Riau menggunakan seperangkat peralatan seismik pantul dangkal saluran tunggal. Tujuan penelitian ini adalah untuk menunjang penelitian keterdapatan endapan plaser pembawa timah dan unsur tanah jarang (REE). Hasil interpretasi rekaman seismik diperoleh terdapatnya lembah/mangkuk yang terbentuk secara alami akibat adanya terobosan batuan granit, di mana lembah/mangkuk-mangkuk ini merupakan tempat terjadinya sedimentasi dari hasil pelapukan batuan di sekitarnya. Hasil interpretasi rekaman seismik pantul saluran tunggal analog di perairan Todak, Singkep, dapat diklasifikasikan menjadi 3 runtunan yaitu runtunan A, B, dan runtunan C.Kata kunci Data seismik, endapan plaser, lembah/mangkuk, Perairan Todak. Geophysical research at Todak, Singkep, Riau Archipelago Province, by using single channel sahllow seismic refletion. The purpose of research is to support Placer Deposit bearing tin and rare earth element research at this area. From seismic interpretation can be recognized the distribution of valley/bowls which is naturally formed, caused by granite rock intrusion. Those valleys are sedimentation places of wheathered rock from the surrounding area. Beside that, the seismic research also for determining the Placer Deposit thickness. Interpratation of analog single channel seismic records in the Todak waters, Singkep, result 3 seismic sequences and intrusive feature, A sequences, B, and C. Keywords: Seismic data, Placer Deposit, valley/basin, Todak Watres

Mustafa M. A. - One of the best experts on this subject based on the ideXlab platform.

  • Indikasi Keterdapatan Endapan Plaser Pembawa Timah dan Unsur Tanah Jarang (Ree), di Perairan Todak, Singkep, Kepulauan Riau
    Indonesian Ministry of Energy and Mineral Resources, 2015
    Co-Authors: Kamiludin U., Astawa I. N., Mustafa M. A.
    Abstract:

    Penelitian geofisika di Perairan Todak, Singkep, Kepulauan Riau menggunakan seperangkat peralatan seismik pantul dangkal saluran tunggal. Tujuan penelitian ini adalah untuk menunjang penelitian keterdapatan endapan plaser pembawa timah dan unsur tanah jarang (REE). Hasil interpretasi rekaman seismik diperoleh terdapatnya lembah/mangkuk yang terbentuk secara alami akibat adanya terobosan batuan granit, di mana lembah/mangkuk-mangkuk ini merupakan tempat terjadinya sedimentasi dari hasil pelapukan batuan di sekitarnya. Hasil interpretasi rekaman seismik pantul saluran tunggal analog di perairan Todak, Singkep, dapat diklasifikasikan menjadi 3 runtunan yaitu runtunan A, B, dan runtunan C.Kata kunci Data seismik, endapan plaser, lembah/mangkuk, Perairan Todak. Geophysical research at Todak, Singkep, Riau Archipelago Province, by using single channel sahllow seismic refletion. The purpose of research is to support Placer Deposit bearing tin and rare earth element research at this area. From seismic interpretation can be recognized the distribution of valley/bowls which is naturally formed, caused by granite rock intrusion. Those valleys are sedimentation places of wheathered rock from the surrounding area. Beside that, the seismic research also for determining the Placer Deposit thickness. Interpratation of analog single channel seismic records in the Todak waters, Singkep, result 3 seismic sequences and intrusive feature, A sequences, B, and C