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Abstrak :
Telah dibuat lapisan tipis (thin film) Seng sulfida (ZnS) dan Seng sulfida-Mangan (ZnS:Mn) pada substrat kaca dengan laju deposisi yang berbeda dengan cara evaporasi termal dan co-evaporasi termal di dalam bejana vakum. Pengukuran terhadap karakteristik impedansi lapisan tipis ZnS dan ZnS:Mn dilakukan di luar vakum untuk frekuensi yang bervariasi antara ribuan hingga jutaan hertz dan laju deposisi yang berbeda dengan ketebalan yang tetap. Ternyata pada daerah frekuensi 1 KHz sampai dengan 10 KHz terjadi penurunan impedansi yang relatif tajam, namun laju penurunan tersebut mulai berkurang pada daerah frekuensi di atas 10 KHz hingga sedikit di bawah 1 MHz. Pada daerah frekuensi di atas 1 MHz bahkan terjadi kenaikan harga impedansi yang menunjukkan telah terjadi gejala relaksasi pada lapisan tipis ZnS dan ZnS:Mn yang diamati. Hasil lain yang diperoleh bahwa permitivitas relatif (K) yang terbentuk pada lapisan tipis tersebut meningkat pengaruhnya pada frekuensi di atas 10 KHz sehingga terlihat bahwa kapasitansi lapisan tipis yang diamati memiliki harga yang tidak konstan, Selain itu nilai kapasitansi dan resistansi lapisan tipis ZnS:Mn mengalami perubahan terhadap variasi kadar Mn dari lapisan tipis tersebut.

Abstrak :
The presence of sulphur compounds in natural gas can interfere to the quality of natural gas. The decline of combustion gas capacity, metal instrument corrosion in gas piping, and the environmental pollution from gas emission can affect by their presence. Bio-filter is one of the methods that selected to reduce sulphur content in natural gas. A lab scale study of hydrogen sulphide reduction in natural gas had conducted in oil and gas field using bio-filter method. The bio-filter system (±1 L volume) contains an active carbon and thiosulphide medium as a substrate, Thiobacillus thioparus as a single culture of sulphur bacteria, and Thiobacillus thioparus with sludge as a mixed culture of sulphur bacteria. The study of hydrogen sulphide reduction was conducted with continuous flow line process. The gas flow rate approximately 1.5 L/min with a fluctuate presence of Hydrogen sulphide (approximately 40 - 70 mg/L). The bio-filter system contains active carbon, thiosulphide medium, and single culture of T. thioparus appear as a good filter for hydrogen sulphide reduction. During 24 hours, the hydrogen sulphide reduction obtains 93% to 16%. When culture media added, the hydrogen sulphide reduction will increase almost 60% and then the reduction decrease to 4% after 20 hours. It is concluded that the bio-filter have potential to develop for sulphur reduction in natural gas.

Abstrak :
[Blowout dan muncul serta tersebarnya gas Hidrogen Sulfida merupakan bahaya khusus dari kegiatan pemboran (NIOSH, 1983). Sehingga dibutuhkan petugas khusus untuk penanganan bahaya paparan gas H2S yang disebut H2S engineer yang melakukan pekerjaan H2S Safety Monitoring. Pekerjaan ini berisiko tinggi sehingga H2S Engineer dituntut memiliki pengetahuan yang lebih mendalam tentang bahaya paparan gas H2S serta pengendaliannya. Tesis ini membahas tentang evaluasi pengetahuan kerja H2S Engineer pada pekerjaan H2S safety monitoring di PT.DE. Tujuannya adalah untuk mengetahui dan mengevaluasi gambaran pengetahuan kerja H2S engineer pada pekerjaan H2S safety monitoring. Penilaian pengetahuan dilakukan dengan memberikan kuesioner tentang pengetahuan kerja h2s safety monitoring kepada 30 orang h2s engineer PT.DE. Berdasarkan hasil penelitian diketahui tingkat pengetahuan kerja H2S Engineer masuk dalam kategori tingkat pengethauan sedang, boleh dikatakan belum maksimal. Dengan adanya gambaran tingkat pengetahuan kerja H2S Engineer diharapkan nantinya dapat dilakukan perbaikan yang dapat meningkatkan prestasi kerja perusahaan maupun H2S Engineer itu sendiri. Diperlukan pelatihan rutin, supervisi, serta penelitian-penelitian untuk mengetahui perkembangan pengetahuan kerja H2S Engineer secara berkala.;Blowout and H2S poison gas release both are specific hazard for drilling activities (NIOSH, 1983). Its important to required special personnel as a H2S Engineer to provide H2S Safety Monitoring work at drilling site. H2S Engineer must have a good working knowledge about H2S Safety Monitoring work related the high risk job. This thesis discusses the evaluation of H2S Engineer job knowledge in H2S safety monitoring work. Research conducted at PT. DE as a H2S safety monitoring services company. The objective is to describe the job knowledge of H2S Engineer. Assessment conducted by distributing questionnaires about H2S Safety Monitoring work to all of H2S Engineer PT.DE. Based on the results of research known levels of H2S Engineer working knowledge in the category of medium-level knowledge, arguably not maximized. The level of working knowledge H2S Engineer expected to improving company performance and H2S Engineer itself. Required regular training, supervision, and research to determine the development of H2S Engineer working knowledge regularly.;Blowout and H2S poison gas release both are specific hazard for drilling activities (NIOSH, 1983). Its important to required special personnel as a H2S Engineer to provide H2S Safety Monitoring work at drilling site. H2S Engineer must have a good working knowledge about H2S Safety Monitoring work related the high risk job. This thesis discusses the evaluation of H2S Engineer job knowledge in H2S safety monitoring work. Research conducted at PT. DE as a H2S safety monitoring services company. The objective is to describe the job knowledge of H2S Engineer. Assessment conducted by distributing questionnaires about H2S Safety Monitoring work to all of H2S Engineer PT.DE. Based on the results of research known levels of H2S Engineer working knowledge in the category of medium-level knowledge, arguably not maximized. The level of working knowledge H2S Engineer expected to improving company performance and H2S Engineer itself. Required regular training, supervision, and research to determine the development of H2S Engineer working knowledge regularly;Blowout and H2S poison gas release both are specific hazard for drilling activities (NIOSH, 1983). Its important to required special personnel as a H2S Engineer to provide H2S Safety Monitoring work at drilling site. H2S Engineer must have a good working knowledge about H2S Safety Monitoring work related the high risk job. This thesis discusses the evaluation of H2S Engineer job knowledge in H2S safety monitoring work. Research conducted at PT. DE as a H2S safety monitoring services company. The objective is to describe the job knowledge of H2S Engineer. Assessment conducted by distributing questionnaires about H2S Safety Monitoring work to all of H2S Engineer PT.DE. Based on the results of research known levels of H2S Engineer working knowledge in the category of medium-level knowledge, arguably not maximized. The level of working knowledge H2S Engineer expected to improving company performance and H2S Engineer itself. Required regular training, supervision, and research to determine the development of H2S Engineer working knowledge regularly, Blowout and H2S poison gas release both are specific hazard for drilling activities (NIOSH, 1983). Its important to required special personnel as a H2S Engineer to provide H2S Safety Monitoring work at drilling site. H2S Engineer must have a good working knowledge about H2S Safety Monitoring work related the high risk job. This thesis discusses the evaluation of H2S Engineer job knowledge in H2S safety monitoring work. Research conducted at PT. DE as a H2S safety monitoring services company. The objective is to describe the job knowledge of H2S Engineer. Assessment conducted by distributing questionnaires about H2S Safety Monitoring work to all of H2S Engineer PT.DE. Based on the results of research known levels of H2S Engineer working knowledge in the category of medium-level knowledge, arguably not maximized. The level of working knowledge H2S Engineer expected to improving company performance and H2S Engineer itself. Required regular training, supervision, and research to determine the development of H2S Engineer working knowledge regularly]

Abstrak :
Penelitian ini dilakukan untuk mengevaluasi prospek endapan VMS di area penelitian ‘X’ Kabupaten Bone, Sulawesi Selatan dengan menggunakan metode resistivitas yang terintegrasi dengan polarisasi terimbas. Terdapat 15 lintasan pengukuran dengan konfigurasi wenner. Panjang lintasan pengukuran 750 meter, spasi elektroda 10 meter, dan jarak antar lintasan 100 meter. Penelitian ini dilakukan dengan metode inversi dua dimensi dengan metode inversi least-squares smoothness-constrained, dan visualisasi tiga dimensi dengan metode interpolasi inverse distance weighting. Area penelitian ini memiliki persebaran nilai resistivitas yang bervariasi mulai dari 6.12 ohm.m sampai 850 ohm.m dan memiliki sebaran nilai chargeability yang bervariasi mulai dari 0 msec sampai 12 msec. Kombinasi nilai resistivitas rendah dan chargeability rendah berkorelasi dengan zona lemah sebagai indikator alterasi hidrotermal dan berfungsi sebagai aliran/sirkulasi fluida hidrotermal dalam membawa mineral sulfida. Sementara integrasi nilai resistivitas menengah dan chargeability tinggi berkorelasi akumulasi mineral sulfida yang diinterpretasikan sebagai area potensi endapan VMS. Secara keseluruhan, area penelitian memiliki potensi endapan VMS dengan pola terpusat pada bagian timur area penelitian. Zona potensi endapan VMS yang direkomendasikan adalah zona yang terletak di lintasan E, F, G, dan M. ......This study was conducted to evaluate the prospect of VMS deposits in the research area 'X' in Bone District, South Sulawesi using the resistivity method integrated with induced polarization. There are 15 measurement lines with a wenner configuration. The length of the measurement line is 750 meters, electrode spacing is 10 meters, and the distance between lines is 100 meters. This study was conducted using a two-dimensional inversion method with a least-squares smoothness-constrained inversion method, and three-dimensional visualization using an inverse distance weighting interpolation method. This research area has a distribution of resistivity values ranging from 6.12 ohm.m to 850 ohm.m and has a chargeability value distribution ranging from 0 msec to 12 msec. A combination of low resistivity and low chargeability values is correlated with weak zones as indicators of hydrothermal alteration and function as a flow/circulation of hydrothermal fluids carrying sulfide minerals. While the combination of moderate resistivity values and high chargeability values is correlated with the accumulation of sulfide minerals, which are interpreted as potential VMS deposit areas. Overall, the research area has potential VMS deposits with a pattern centered on the eastern part of the research area. The recommended potential VMS deposit zone is the zone located on lines E, F, G, and M.

Abstrak :
Kucing Liar (KL) merupakan endapan Cu-skarn terbesar dan signifikan di skala dunia yang terletak di Tembagapura, Papua, Indonesia. Endapan ini merupakan bagian dari wilayah penambangan PT. Freeport Indonesia yang telah beroperasi sejak tahun 1967, akan tetapi, sampai saat ini proses genesa atau pembentukan endapan Kucing Liar masih diperdebatkan apakah terbentuk akibat intrusi atau proses pensesaran karena ditemukan sebuah sesar besar yang memotong perlapisan di endapan ini. Untuk membantu menjawab pertanyaan tersebut, penulis melakukan penelitian pada area ini dengan menganalisis data yang didapat dari kegiatan core detailed logging dan core orienting dari 6 lubang bor yang representatif, yang dilanjutkan dengan menganalisis sayatan tipis untuk mengkonfirmasi hasil detailed logging. Interpretasi hasil penelitian secara singkat menyatakan bahwa deposit ini dihasilkan dari salah satu tubuh Grasberg Intrusion Complex (GIC) yang memotong batuan sedimen karbonatan berumur Kapur Akhir hingga Miosen. Lokasi intrusi tidak dapat diidentifikasi secara spesifik, tetapi diinterpretasi intrusi ini memotong stratigrafi mulai terdiri dari Kelompok Kembelangan (KG) sampai Kelompok Batugamping Papua New Guinea (PNGLG) yang lebih muda. Sistem hidrotermal yang berasal dari proses pembekuan intrusi magma kemudian menghasilkan alterasi skarn yang terpusat di interval bawah Formasi Batu Gamping Waripi (Tw1) dan interval atas Formasi Batu Gamping Ekmai. Sistem alterasi skarn juga merupakan host mineralisasi sulfida (pirit-kalkopirit-bornit-kovelit) yang mengandung bijih (ore) tembaga (Cu) yang merupakan objek tambang dari endapan ini. Alterasi skarn di area ini dibagi menjadi 9 zona berdasarkan asosiasi mineral alterasi yang terbentuk, sedangkan mineralisasi sulfida dikelompokkan menjadi 6 tipe (styles) berdasarkan kenampakan dan konsentrasinya. Tipe mineralisasi yang berbeda dihasilkan dari perbedaan porositas / permeabilitas batuan induk dan tingkat alterasinya. Endapan Kucing Liar juga dipotong oleh sesar naik bernama Sesar Idenberg No. 1, seperti yang telah disebutkan sebelumnya. Dampak proses pensesaran pada endapan Kucing Liar juga merupakan topik penelitian yang menarik yang terus dikaji semenjak eksplorasi sampai produksi guna membantu memperkirakan cadangan bijih dari endapan. Dalam makalah ini, analisis mengenai kontrol struktur besar terhadap sistem alterasi dan mineralisasi sulfida didasarkan pada zonasi alterasi yang telah dibuat penulis dan distribusi konsentrasi sulfida hasil logging dari keenam lubang bor. Untuk mendukung analisis kontrol struktur pada area ini, penulis juga menganalisis tren orientasi urat hidrotermal menggunakan bantuan perangkat lunak Dips. Analisis urat hidrotermal dilakukan terhadap 4 jenis urat, yaitu kalsit, kuarsa, anhidrit, dan sulfida, dan menunjukkan 3 tren pengendapan urat berbeda yang dipengaruhi oleh sifat formasi dan proses pensesaran

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Kucing Liar (KL) is the biggest and significant Cu-skarn deposit around the world that is located in Tembagapura, Papua, Indonesia. This deposit is a part of PT.Freeport Indonesia mining area that has been operated since 1967, nonetheless, the generation process of Kucing Liar deposit is still being debated whether it was formed by the intrusion or by the late faulting process that is indicated from the presence of Idenberg Fault No.1. To help answering this question, the writer did a research in this area with data generated from core detailed logging and core orienting activity of 6 representative boreholes of this deposit, then the analysis is continued by analyzing the thin section of the samples. The recent and scientifically proven interpretation states that this deposit was generated from one of the Grasberg Intrusion Complex (GIC) that cut through the carbonaceous sedimentary rocks of Late Cretaceous to Miocene ages. The intrusion location can not be specifically identified but strongly believed had cut through the rocks of Kembelangan Group (KG) and Papua New Guinea Limestone Group (PNGLG). The hydrothermal system derived from the magma emplacement of intrusion then created the skarn alteration system that are mainly hosted in Lower Waripi Limestone Formatiom (Tw1) and Upper Ekmai Limestone Formation. The skarn alteration system has also been the host of sulphide mineralization (pyrite-chalcopyrite-bornite-covellite) that has been the ore of the deposit for its high Cu content. The skarn alteration is divided into 9 zonation based on their formed or altered mineral association, meanwhile the sulphide mineralization is grouped into 6 styles based on their appearence and concentration. The different styles are interpretated to be the function of host rock porosity/permeability and its degree of alteration. The Kucing Liar deposit is also cut by a thrust fault, named Idenberg Fault No. 1, as mentioned before. The impact of major faulting process on Kucing Liar deposit also has been an interesting research topic and continually analyze through time of exploration and production to help estimating the reserved ores. In this paper, this analysis is based on the the alteration zonation and the sulphide concentration distribution datas of 6 boreholes. To support the geological structure control analysis on this area, the writer also analyze the trend of hydrothermal vein orientation with the help of Dips software. The hydrothermal vein analysis from 4 types of vein, calcite, quartz, anhydrite, and sulphide, shows there are 3 trends of vein deposition orientation that were influenced by the formation properties and the late faulting process.

Abstrak :
Telah dibuat lapisan tipis ZnS tanpa tambahan Sulfur dan dengan tambahan Sulfur dengan metode evaporasi termal. Pola difraksi yang didapat dengan karakterisasi XRD menunjukkan bahwa lapisan tipis ZnS yang dibuat dengan dan tanpa tambahan Sulfur memiliki struktur kristal kubik (Zincblende) dengan preferred orientation [111] untuk laju deposisi 6 A/s dan struktur kristal hexagonal (wurtzite) dengan preferred orientation [0021 untuk laju deposisi 20 Vs. Lapisan tipis yang didapat berbentuk polikristal, hal ini menunjukkan struktur kolumnar yang memang biasanya dimiliki oleh lapisan tipis yang dibuat dengan metode PVD. Juga diamati untuk sampel dengan laju deposisi lebih tinggi mempunyai ukuran butir yang lebih kecil. Dari analisa EDAX diketahui semua sampel kelebihan sulfur baik yang dibuat dengan tambahan Sulfur maupun tanpa tambahan Sulfur. Pengukuran konduktivitas terhadap temperatur menunjukkan lapisan tipis ZnS yang dibuat mempunyai perilaku semikonduktor. Sampel dengan laju deposisi rendah mempunyai hambatan jenis ~106 Ωcm dan sampel dengan laju deposisi tinggi mempunyai hambatan jenis ~107Ωcm untuk ZnS tanpa tambahan sulfur dan ~109Ωcm untuk ZnS dengan tambahan sulfur. Karakterisasi I-V menunjukkan adanya sifat ohmik, non ohmik dan destructive breakdown pada medan ± 3 MV/cm. Mekanisme yang terjadi pada medan rendah adalah tunneling dan pada medan tinggi (>1 MV/cm) terjadi pula electron avalanching.