Hasil Pencarian  ::  Simpan CSV :: Kembali

"Proses magmatisme berkaitan dengan jalur tektonik ring of fire, yang menyebabkan proses mineralisasi hidrotermal sehingga membentuk potensi sumber daya mineral di Indonesia. Salah satu endapan hidrotermal yaitu endapan epitermal sulfidasi rendah yang berada di Lapangan “RD”, Cibaliung. Struktur patahan menjadi pengontrol sistem epithermal sulfidasi rendah sebagai tempat terendapkannya mineral emas. Integrasi data geologi dengan geofisika diperlukan dalam menentukan struktur pengontrol dan zona potensi mineralisasi. Mineral bijih sulfida dapat dibedakan dari sifat kemagnetan dan kelistrikan dikarenakan mineral logam memiliki respon suseptibilitas, resistivitas dan chargeabilitas lebih tinggi dibandingkan dengan mineral non-logam. Zona potensi mineralisasi emas sulfidasi rendah berada pada zona struktur yang didominasi alterasi argilik dan kaya akan mineral sulfida pada alterasi argilik ilitik dengan nilai suseptibilitas menengah hingga tinggi kisaran -83.7 nT – 92.3 nT, resistivitas dengan nilai rendah hingga menengah 0 – 25 ohm.m dan chargeabilitas dengan nilai menengah hingga tinggi 15 - >75 msec. Dari ketiga parameter tersebut, diduga zona mineralisasi berada pada zona struktur patahan berorientasi Baratlaut-Tenggara. Struktur pengontrol zona potensi mineralisasi tersebut berada di lintasan 3 yaitu patahan D dip 62° ke arah NE dan patahan E dip 83° ke arah NE. Lintasan 4 yaitu patahan D dip 79° ke arah NE, patahan E dip 77° ke arah NE dan patahan F dip 73° ke arah NE. Lintasan 7 yaitu patahan D dip 80° ke arah SW dan patahan E dip 75° ke arah NE. Lintasan 8 yaitu patahan D dip 84° ke arah NE dan patahan E dip 66° ke arah NE. Lintasan 9 yaitu patahan A dip 70° ke arah SW dan patahan B dip 81° ke arah NE.

---

The magmatism process is related to the Ring of Fire tectonic pathway, which causes a hydrothermal mineralization process to form potential mineral resources in Indonesia. One of the hydrothermal deposits is an epithermal low-sulfidation deposit in the "RD" Field, Cibaliung. The fault structure controls the epithermal low-sulfidation system as a place for gold mineral deposition. Integration of geological data with geophysical data is required in determining the controlling structure and potential mineralization zone. Sulfide ore minerals can be distinguished from their magnetic and electrical properties because metal minerals have a higher susceptibility, resistivity and chargeability response compared to non-metallic minerals. The potential zone of low sulfidation gold mineralization is located in the structure zone which is dominated by argillic alteration and rich in sulphide minerals in Illitic argillic alteration has medium to high susceptibility values ranging from -83.7 nT - 92.3 nT, resistivity with low to medium values 0 - 25 ohm.m and chargeability with medium to high values of 15 -> 75 msec. From those three parameters, it is assumed that the mineralization zone is located in the NW-SE oriented fault structure zone. The controlling structure for the zone of mineralization potential is in line 3 is fault D with dip 62° to the NE and the E fault with dip 83° to the NE. Line 4 is fault D with dip 79° to the NE, fault E with dip 77° to the NE and fault F with dip 73° to the NE. Line 7, is fault D with dip 80 ° to the SW and the E fault dip 75° to the NE. Line 8 is fault D with dip 84° to the NE and fault E with dip 66 ° to the NE. Line 9 is fault A with dip 70° SW and fault B with dip 81° to NE."

"Penelitian ini dilakukan di lapangan GB untuk mendeteksi keberadaan mineral emas dengan metode Induced Polarization IP . Berdasarkan geologi, terdapat adanya sistem epitermal sulfidasi tinggi di wilayah ini. Hal ini ditandai dengan munculnya keberadaan mineral-mineral logam seperti Au, Cu, dan konsentrasi yang cenderung asam di permukaannya. Mineral emas sendiri merupakan mineral yang bersifat diamagnetik, lunak, dan berasosiasi dengan mineral sulfida. Emas terbentuk akibat dari adanya proses magmatisme atau pengkonsentrasian di permukaan. Mineral emas terangkut oleh fluida hidrotermal ke permukaan dan terbentuk dalam lingkungan hidrotermal dimana ia terbawa ke permukaan bersama dengan senyawa-senyawa yang berikatan dengannya. Metode IP memanfaatkan beda potensial sebagai parameter dalam melakukan pengukuran untuk mendeteksi keberadaan mineral-mineral konduktif di bawah permukaan tanah. Kelebihan metode IP dibanding metode lain adalah kemampuannya mendeteksi mineral logam yang tersebar. Pada penelitian ini digunakan dari 6 data line IP yang dibentangkan ke arah Barat ndash; Timur serta didukung oleh data magnetik. Data diolah dengan inversi 2D dan dimodelkan secara 3D dengan membentangkan hasil secara paralel. Hasilnya, nilai chargeability tertinggi bernilai > 200 ms pada kedalaman 400 meter. Hal ini didukung dengan nilai resistivity yang mencapai > 1000 ohm-meter. Dari data magnetik, nilai magnetik berkisar antara -199.3 nT sampai 244 nT.

---

This research was conducted in field GB to identify the presence of gold minerals by Induced Polarization IP method. Based on geology, there is a high sulfidation epithermal system in the region. This can be determined by the presence of metal minerals such as Au, Cu, and acid concentrations on the surface. Gold is a typical of mineral that is diamagnetic, pliable, and associated with sulphide minerals. It is formed as a result of the process of magmatism or metasomatism on the surface. The hydrothermal fluid content transports gold to the surface along with the other elements associated to it and is formed in hydrothermal environment. The IP method utilizes a potential difference as a parameter in performing measurements to detect the presence of underground conductive minerals. The advantage of IP methods compared to other methods is its ability to detect disseminated conductive minerals. This research use 6 line datas of IP which is extended to West ndash East and supported by magnetic data. Data is processed with 2D inversion and modeled in 3D by spreading results in parallel. As a result, the highest value of chargeability is 200 ms at a depth of 400 meters. This is supported by a resistivity value of 1000 ohm meter. From magnetic data, magnetic values range from 199.3 nT to 244 nT."

"Telah dilakukan identifikasi zona mineralisasi emas pada lapangan ldquo;GB rdquo; dengan menggunakan inversi 3D data magnetik. Lapangan ldquo;GB rdquo; merupakan daerah prospek mineral emas yang terletak di provinsi Jambi, Indonesia. Tipe mineralisasi pada lapangan tersebut berupa Epitermal Sulfidasi Tinggi dan porfiri Cu-Au yang telah terbentuk pada lingkungan hidrotermal. Karakteristik batuan ini adalah batuan intrusi intermediet asam sebagai batuan induknya. Batuan ini mengandung mineral bijih utama berbentuk tembaga dan emas serta mineral pengikut lainnnya yang bersifat magnetik. Oleh karena itu, metode magnetik sangat sensitif untuk mengidentifikasi daerah prospek mineralisasi emas. Pada penelitian ini akuisisi dilakukan dengan jarak 5 m antar titik stasiun yang terdiri dari 51 lintasan dengan jarak antar lintasan 100 m dan total panjang lintasan 16,5 kilometer. Identifikasi posisi, jenis serta kedalaman struktur bawah permukaan yang berhubungan dengan zona pembentukan emas diatas, dilakukan analisis derivatif dari perhitungan first horizontal derivative dan dekonvolusi Euler. Selanjutnya dilakukan pemodelan inversi dalam 3D untuk mengetahui gambaran yang lebih objektif dari tubuh batuan bawah permukaan. Dalam penelitian ini, data IP induced polarization digunakan untuk memverifikasi hasil data magnetik dengan melihat parameter resistivity dan chargeability zona prospek. Begitu juga dengan data geologi yang digunakan untuk mengetahui sebaran batuan yang menjadi lingkungan pengendapan emas. Hasil akhir penelitian ini teridentifikasi zona mineralisasi emas berada berupa lithocap dan body intrusi dengan perkiraan top body berada pada kedalaman 80 m dari permukaan topografi.

---

Identification of gold mineralization zone in ldquo GB rdquo field had been done using 3D Inversion magnetic data. ldquo GB rdquo field is a gold mineral prospect field, located in Jambi province, Indonesia. Mineralization type of this area are high epithermal sulphidation and porphyry Cu Au that have been formed in hydrothermal environment. The characteristic of this type is intermediate acid igneous rock as the host rock. This rock consist of mineral ores such as copper gold and magnetic gangue minerals. Therefore, magnetic method is very sensitive to identify gold mineral prospect zone. In this research, magnetic data was acquired by 5 m spacing between each station, that are consist of 51 lines with 100 m space between lines and the total length of lines is 16.5 kilometer. Identifying position, types and depth of subsurface structure relating to gold deposition environment, derivative analysis is done with first horizontal derivative and euler deconvolution calculation. Then, we make 3D inversion model, to delineate the subsurface structure objectively. In this research, induced polarization data is used to see resistivity and chargeability parameter of the prospect zone and also geological data to find out distribution of rock that associated with gold deposition environment. The result of this research, gold deposition zone is identified by lithocap and intrusion body with top of instruction rock at depth 80 m from the surface."

"Aplikasi metode Resistivity dan Induced Polarization untuk mendeteksi bawah permukaan yang berhubungan dengan pembentukan deposit emas sistem epithermal. Data yang diproses adalah hasil pengukuran dengan konfigurasi Dipole-dipole, dengan spasi elektroda 5 meter. Panjang lintasan 200 meter, sehingga penetrasi kedalaman mencapai 50 meter. Pengolahan data dengan menggunakan software RES2DINV, didapatkan pencitraan model 2Dbawah permukaan yang terdiri dari lapisan batuan vulkanik (resistivity 200-1000 ohmm), lapisan batuan alterasi (resistivity <100 ohm-m) dan lapisan silifikasi (resistivity 200-300 ohm-m) . Deposit emas diduga berada di lapisan batuan alterasi dan lapisan silifikasi yang memiliki chargeability >200 msec. Dengan prediksi cadangan emas di lintasan 1 dan 2 sebesar 260.77 kg.

---

The application of method Resistivity and Induced Polarization to detect subsurface formation associated with deposits of gold epithermal system. The processed data is measured with Dipole-dipole configuration, with electrodes spaced 5 meters. Path length 200 meters, so the expected penetration depth reaches 50 meters. Data processing use software RES2DINV, is obtain imaging the model 2D subsurface that consist of the layer of the volcanic rock (resistivity 200-1000 ohm-m), the layer of the rock altered (resistivity 100 ohm-m) and the layer of silification (resistivity 200-300 ohm-m). Deposit gold is expect is in the layer of the rock altered and the layer silification that had chargeability >200 msec, with the prediction of the gold reserve in the line 1 and 2 as big as 260.77 kg."

"Lingkungan endapan bijih epitermal low sulfidation masih menjadi studi yang menarik untuk di teliti lebih jauh. Kedalaman pembentukan pada umumnya terbilang cukup dangkal sekitar 100-600 meter namun yang menjadi kesulitan utama adalah sedikitnya singkapan yang terdeteksi di permukaan. Secara teoritik penyebaran urat-urat yang menjari juga menjadi penyebab sulitnya interpretasi body anomaly. Pada penelitian di daerah “B” zona mineralisasi terdeteksi oleh metode IP yang dicerminkan oleh nilai chargeability > 300 ms. Metode IP mendapatkan hasil yang baik karena pada lingkungan low sulfidation yang merupakan endapan dekat permukaan dapat memiliki alterasi lempung sehingga respon IP dapat lebih maksimal. Pada daerah “B” terbaca nilai anomali resistivitas sebesar >300 Ohm.m diduga daerah tersebut merupakan zona intrusi, sementara nilai resistivitas rendah yang terdeteksi di sisi timur diperkirakan berasal dari batuan ubahan atau alterasi. Selanjutnya metode magnetik digunakan untuk melokalisasi zona mineralisasi logam yang berasosiasi dengan kuarsa sebagai mineral gaunge dengan nilai anomali menurun sampai <45000 nT. Dengan hasil interpretasi terpadu dari ketiga metode tersebut diharapkan dapat menentukan zona mineralisasi emas yang ditunjukkan oleh nilai anomali tinggi pada ketiga metode sehingga kesuksesan rasio pemboran dalam eksplorasi mineral emas dapat ditingkatkan.

---

Environment of low sulfidation epithermal ore deposition is still a fascinating study to be investigated further. Formation is generally shallow depth of about 100-600 meter. On the surface outcrops become a major factor in the difficulty of detecting subsurface structure in the high sulfidation. Theoretically branched deployment veins are also the cause of the difficulty of interpretation of the anomalous body. This is certainly a challenge for the geophysical world today. Of this problem resistivity method is very effective in finding the existence of anomalous body. On the study at the area "B" zones of mineralization detected by the IP method represented by chargeability values > 300 ms. IP methods obtain good results because of the low sulfidation environment that is close to the surface of the deposition may have clay alteration that can more optimally IP response. In the area "B" reads the value of anomalous resistivity of > 300 Ohm.m supposedly the area was a zone of intrusion, while the low resistivity values were detected on the east side is estimated to come from the rocks change or alteration. The next magnetic method is used to localize metal mineralized zones assosiated with quartz as gaunge mineral with anomalous values decreased to <45000 nT. With an integrated interpretation as the results of the three methods is expected to determine the zones of gold mineralization indicated by the high anomaly on all three methods so that the drilling success ratio can be improved gold mineral exploration."

"[ABSTRAKKemampuan inhibitor Triazine dalam menginhibisi baja karbon API 5L X60 dalam lingkungan NaCl 3.5% diinvestigasi dengan menggunakan metode Polarisasi Tafel dalam berbagai variasi konsentrasi. Konsentrasi yang digunakan pada penelitian kali ini adalah 0 ppm, 50 ppm, 10 ppm, 150 ppm, 200 ppm, dan 250 ppm. Efisiensi optimum yang didapatkan adalah sebesar 50.28% dengan konsentrasi inhibitor triazine sebesar 150 ppm. Dengan pengujian FTIR, maka dibuktikan bahwa senyawa triazine mampu menginhibisi permukaan baja API 5L X60. Penelitian ini juga membuktikan bahwa inhibitor triazine merupakan inhibitor korosi karena mampu menurunkan laju korosi.Inhibitor triazine termasuk kedalam jenis inhibitor campuran.

---

ABSTRACT

The corrosion rate from Triazine-based inhibitors on API 5-L X60 steel at NaCl 3,5% environtment were investigated using the Tafel Polarization method. The Triazine compounds that successfully absorbed onto steel surface were investigated using the Fourier Transform Infra Red (FTIR). Triazine?s efficiency depends on the concentration that given onto environtment. The highest efficiency of Triazine inhibitor is 50.28% with the optimize concentration 150 ppm. The investigated Triazine inhibitors were proven as the corrosion inhibitors because it can reduces the corrosion rate. Triazine inhibitors are also mixed type inhibitors.;The corrosion rate from Triazine-based inhibitors on API 5-L X60 steel at NaCl 3,5% environtment were investigated using the Tafel Polarization method. The Triazine compounds that successfully absorbed onto steel surface were investigated using the Fourier Transform Infra Red (FTIR). Triazine?s efficiency depends on the concentration that given onto environtment. The highest efficiency of Triazine inhibitor is 50.28% with the optimize concentration 150 ppm. The investigated Triazine inhibitors were proven as the corrosion inhibitors because it can reduces the corrosion rate. Triazine inhibitors are also mixed type inhibitors. , The corrosion rate from Triazine-based inhibitors on API 5-L X60 steel at NaCl 3,5% environtment were investigated using the Tafel Polarization method. The Triazine compounds that successfully absorbed onto steel surface were investigated using the Fourier Transform Infra Red (FTIR). Triazine’s efficiency depends on the concentration that given onto environtment. The highest efficiency of Triazine inhibitor is 50.28% with the optimize concentration 150 ppm. The investigated Triazine inhibitors were proven as the corrosion inhibitors because it can reduces the corrosion rate. Triazine inhibitors are also mixed type inhibitors. ]"

"[Logam merupakan kebutuhan utama dari infrastruktur pada industri. Korosi pada logam merupakan suatu hal yang tidak dapat dihindari, dan seringkali menjadi penyebab utama kegagalan dalam berbagai industri, terutama industri minyak dan gas yang berada di lepas pantai. Pemilihan material yang sesuai dapat mencegah terjadinya korosi pada industri, sehingga meminimalisir penggantian komponen dalam waktu yang singkat.Penelitian ini dilakukan untuk mempelajari perilaku korosi pada pipa baja tahan karat austenitik 316L pada lingkungan NaCl yang bervariasi. Parameter elektrokimia dievaluasi dengan menggunakan metode polarisasi siklik untuk mengetahui perilaku korosi yang terjadi pada lingkungan NaCl. Pemanasan dilakukan untuk mendapatkan perbedaan bentuk mikrostruktur dari keadaan awal. Kemudian diuji didalam lingkungan NaCl 3,5% yang memiliki kelarutan oksigen tertinggi dan bandingkan dengan logam yang tidak dipanaskan pada konsentrasi yang sama.Hasil penelitian menunjukkan bahwa ketahanan korosi berubah berdasarkan konsentrasi NaCl, logam paling tahan dengan korosi pada NaCl 1%, dan paling lemah ketahanannya pada NaCl 3,5%. Perubahan mikrostruktur yang menjadi lebih tidak seragam dan kemunculan sensitasi menurunkan ketahanan korosi. Dari hasil polarisasi siklik didapati bahwa mekanisme korosi pada lingkungan NaCl adalah korosi sumuran.

---

Steels are basic needs for industrial infrastructure. Corrosion in steels can?t be avoided and often plays a role as a major cause of failure in industries, especially offshore oil and gas. Proper material selection is one of the best ways to prevent corrosion and minimize component replacement caused by corrosion.This study investigates corrosion behaviour of austenitic stainless steel 316L in various NaCl solutions. Electrochemical parameter is evaluated by cyclic polarization, and also to determine which corrosion behaviour has occurred. Heat is given to obtain different microstructure shapes from the initial one. Then tested in 3.5% NaCl solution and compared to the un-heated with the same solution concentration.The results shown that corrosion resistance affected by Chloride presence, with 1% concentration was the strongest, and 3.5% was the most susceptible. Microstructure transformation to more un-uniform than before heated, and presence of sensitization decreases the corrosion resistance. From the cyclic curve, it is known that the corrosion behaviour that occurred was pitting corrosion., Steels are basic needs for industrial infrastructure. Corrosion in steels can’t be avoided and often plays a role as a major cause of failure in industries, especially offshore oil and gas. Proper material selection is one of the best ways to prevent corrosion and minimize component replacement caused by corrosion.This study investigates corrosion behaviour of austenitic stainless steel 316L in various NaCl solutions. Electrochemical parameter is evaluated by cyclic polarization, and also to determine which corrosion behaviour has occurred. Heat is given to obtain different microstructure shapes from the initial one. Then tested in 3.5% NaCl solution and compared to the un-heated with the same solution concentration.The results shown that corrosion resistance affected by Chloride presence, with 1% concentration was the strongest, and 3.5% was the most susceptible. Microstructure transformation to more un-uniform than before heated, and presence of sensitization decreases the corrosion resistance. From the cyclic curve, it is known that the corrosion behaviour that occurred was pitting corrosion.]"

"Telah dibuat alat pengukur beda potensial material, dimana pengukuran ini dilakukan dengan menggunakan alat ukur yang dirancang dalam satu rangkaian. Diharapkan alat ukur yang dibuat dapat mengukur beda potensial dari bahan material yang di ujicobakan. Bahan material yang digunakan adalah bahan material multiferroik. Dimana bahan tersebut jika diberikan medan magnet akan timbul medan listrik lalu jika diberikan medan listrik akan timbul medan magnet, dan juga dapat menimbulkan strain pada benda. Sistem alat ukur ini terdiri dari 3 bagian utama yaitu alat ukur yang kami gunakan, instrumentasi alat ukur, komputer sebagai pusat kendali dan pengolahan data dan labview sebagai bahasa pemprograman. Metode pengukuran menggunakan sensor arus yang sudah dirancang dalam satu rangkaian power supply.

---

Has been made the potential difference of material measurement system with design using one circuit only.The purpose of this measurement is measure the potential difference of materialused called by multiferroic. Multiferroics are material, which can generate the electrical field after given magnetic field, likewise the magnetic field can generate electrical field. This material also can develop strain by applying these forces. There are three main systems on this measurement and they are instrumental measurement, computer control system and Labview as programmer language.The method of this measurement is using current sensor with design in one part of power supply."

"Pemodelan 2D data geofisika polarisasi terimbas domain frekuensi dan magnetik telah berhasil menentukan zona mineralisasi emas pada daerah "A". Pemodelan data polarisasi terimbas dilakukan dengan menggunakan pemodelan balik, sedangkan untuk data magnetik digunakan metode pemodelan maju. Berdasarkan model yang didapatkan, zona mineralisasi emas teramati mulai lintasan 1 sampai dengan lintasan 4 yang berasosiasi dengan nilai tahanan jenis medium (200-600 Ohm-m), dan mengandung PFE > 7%, serta memiliki susceptibilitas yang bernilai negatif. Sedangkan pada lintasan 5, 6, dan 7, diduga tidak terjadi mineralisasi atau diperkirakan mineralisasinya dalam. Berdasarkan kelurusan anomali pola penyebaran mineralisasi emas pada daerah "A" berarah barat daya-timur laut.

---

Two dimensional modeling of geophysical data induced polarization (IP) frequency domain and magnetic has been succeed to determinate the mineralization zone at "A" region. Inverse modeling methode is used to modeling of IP data, and forward modeling methode is used to modeling of magnetic data. Based on model of that geophysical data, the mineralization zone at the "A" region was detected at line 1-4, and it’s indicated with medium resistivity (200-600 Ohm-m), containt high PFE (>7%), and susceptibility with negatif value. In otherwise, at line 5, 6, and 7, the mineralization proccess is not happen or it predicted have deep mineralization. Based on result that have from modeling the gold mineralization direction at "A" region is westsouth-northeast."