Colo Volcano research team. 

The existence of Colo Volcano on the southwest side of the North Arm of Sulawesi Magmatic Arc show evidence of evolutionary difference plate under Tomini Bay. Colo Volcanism activity indicated a product of slab rollback final extension of the Gulf Gorontalo. This study aims to investigate the alterated vulcanic rocks of the Colo Volcano. In this study, petrographic analysis is used to determine mineral composition based on petroscopic. Several lava and pyroclastic outcrops, indicating an alteration of the Colo Volcano product. The analysis showed andesite lava on gray-green thin incisions, subhedral-anhedral shape, mineral composition consist of hornblende (10%), biotite (10%), quartz (15%), pyroxene (10%), orthoclase (10%), Plagioclase (10%), opaque minerals (20%) and glasses (15%). The Orthoclase, is white-blueish-gray, orthorhombic, low cleavage, twinning altered look. Locally shows colorless-blue-grayish, subhedral-anhedral shape, mineral composition consisting of hornblende (10%), biotite (10%), quartz (50%), pyroxene (5%), orthoclase (5%), opaque minerals (15%) and glasses (5%). It might consist of cholorotisation of biotite. The lava exposed on Mount Ambu shows the presence of smectite alteration and pyrite mineralization, on thin incisions including blue-gray-brown, subhedral-anhedral shape, mineral composition consist of hornblende (10%), biotite (5%), quartz (10%), Olivine (5%), plagioclase (20%), orthoclase (15%), opaque minerals (15%) and glasses (20%).

Keywords: Petrography, Colo Volcano, Indonesia, volcanic rock, alteration.

Amin, A.K.M.A., Badaru, A.W.W., Manyoe, I.N., Salama, T.H., and Laseti, K.H. 2017. Petrography Volcanic Rock : Volcanic Rock Alteration Study of Colo Volcano Indonesia. International Conference on Transdisciplinary Approach Research. Universitas Negeri Gorontalo and Ehime University Japan, Indonesia.

Indexed in Google Scholar.

Geology data collection (Manyoe, 2017).

Bone Bolango District is an area that began to evolve so that it takes the energy supply like
geothermal energy to support development. The purpose of this study was to assess the geological conditions of the Lombongo geothermal area. The research location is at coordinates 0°32' N - 0°32'40 "N and 123°10'40"E - 123 ° 11'40" E. Studies conducted on geothermal manifestations, lithology, geomorphology, flow net, and hydrogeological of research area. Observations geothermal manifestations such as physical properties and chemical properties of hot springs. Lithology and geomorphology observations include observations of minerals and landforms. Hydrogeological observations such as flow net, recharge areas, discharge area, and the runoff area. The temperature of hot springs in the Lombongo geothermal area are 420C-480C. The appearance of the hot springs in the Lombongo controlled by strike slip fault. Lombongo geothermal area and the surrounding area consists of volcanic rocks such as andesite and diorite intrusive rocks form. Morphology Lombongo and surrounding area consists of volcanic mountains, denudational hills and denudasional fluvial plains. Recharge area is in the mountains in the northern part of the study area while the discharge area is located in the southern part of the study area. Geological studies of research area shows that the heat source is volcanic body and strike slip fault is the way of hot waters from reservoir to the surface.

Keywords: Geology, Geothermal, Lombongo, Gorontalo.

Manyoe, I.N., dan Bahutalaa, I. 2017. Kajian Geologi Daerah Panas Bumi Lombongo, Kabupaten Bone Bolango, Provinsi Gorontalo. Jurnal Geomine, Vol. 5, No. 1.

Indexed in Google Scholar & Sinta, S4.

Electrical data collection.

Research areas are included in the Boliyohuto District, Gorontalo. Geothermal manifestations in the study area is a pond of hot water with surface temperatures reaching 59?C. Sounding acquisition data with Schlumberger configuration. This study aims to determine the pattern of subsurface configuration based electrical models of the data inversion. The results showed a geothermal reservoir is located on the third layer with high resistivity values >500 Ωm. Intrusive rocks which suffered a suspected fracture geothermal reservoir. Layer I is a cap rock with very low resistivity values

Keywords: Inversion, Electrical, Geothermal, Gorontalo.

Manyoe, I.N. 2016. Model Inversi Data Geolistrik untuk Penentuan Lapisan Bawah Permukaan Daerah Panas Bumi Bongongoayu, Gorontalo. Jurnal Sainstek, Vol. 8, No. 4.

Indexed by Google Scholar. 

Magnetic anomaly distribution data collection.

In 2012 the Geological Agency of Indonesia discovered 14 new geothermal sites in Indonesia, one of which is in the area Diloniyohu (now Bongongoayu) are included in the administrative area of the District Boliyohuto Gorontalo regency. Preliminary investigation geothermal area with geomagnetic methods used to determine the geothermal prospects. This study aimed to analyze the distribution of magnetic anomalies and determine the geothermal prospects based on the distribution of magnetic anomalies. The magnetic survey carried out by the closed-loop system is the measurement starts and ends at the same point. The number of points is 224 points measuring geomagnetic measuring scattered on the 8 track measuring point. The total length of the measuring point is 5.4 Km. The distance between the measuring point is 25 m and the distance between tracks is 100 m. Value IGRF (International Geomagnetic Reference Field), inclination and declination obtained using NGDC Geomagnetic Calculators. By entering coordinates and elevation study site at NGDC Geomagnetic Calculators values obtained IGRF = 40633.97 nT, value Inclination = -14,75° and declination = 0,79° value. The results of the magnetic survey in the form of cross-section of the magnetic anomaly and magnetic anomaly distribution map. Magnetization area which is indicative of reservoir is characterized by low magnetic anomaly (-400 to -150 nT) to moderate magnetic anomalous zone (-150 to 50 nT), which is at the center of the study area. Comprehensive prospecting area is> 320,000 m2 with a volume of 22.4 million m3 reservoir. Integrated investigations should be carried out to the west which is characterized by a moderate magnetic anomalies klosur opening and expanding research into the area of geothermal manifestations appearing more precisely in the area Talumopatu, District Paguyaman Mootilango and upstream watershed.

Keywords: Geothermal, Magnetic, Magnetic Anomali, Bongongoayu.

Manyoe, I.N., Irfan, U.R., dan Suriamiharja, D.A. 2015. Distribusi Anomali Magnetik Daerah Panas Bumi Bongongoayu, Gorontalo. Seminar Ilmiah Nasional Penguatan Kemitraan Berbasis Ipteks Inovasi untuk Kemaslahatan BMI. Fakultas Teknik Universitas Hasanuddin Makassar, Indonesia.

Indexed by Google Scholar. 

Magnetic anomaly cross section data collection.

Bongongoayu area is one of the areas in Gorontalo which is a place of geothermal manifestations (hot water pond) with a surface temperature of 43°- 59°C. This research aimed to analyze sections of magnetic anomalies and electrical. The method used is quantitative research methods. Acquitition data was carried out in the field by using Proton Precission Magnetometer and Resistivity meter. The number of magnetic measuring points is 224 points while the number of electrical sounding is 2 points. Measurements of magnetic and electrical section is shown in the form of magnetic anomalies and electrical section. The results showed that the geological structure and litology in the area of Bongongoayu geothermal obtained by the magnetic anomaly sections. Indication of the geological structure and litology in the section of magnetic anomalies obtained by contrasting positive and negative anomalies values (> 300 nT). Negative magnetic anomalies on the L1 – L7 dominate the northwestern part of the track while the southeastern part of the track is dominated by positive magnetic anomalies. Based on the electrical section, the cap rock characterized by low resistivity values ( 500 Ωm). Section of magnetic and electrical anomalies indicate that the geological structures (> 300 nT) are trending Northeast - Southwestern is a factor controlling of fluid in Bongongoayu geothermal area, Gorontalo.

Keywords : Section, Magnetic, Electrical, Geothermal, Gorontalo.

Manyoe, I.N., Irfan, U.R. and Suriamiharja, D.A. 2014. Penampang Anomali Geomagnet dan Geolistrik Daerah Panas Bumi Bongongoayu, Gorontalo. e-journal Pasca UNHAS.

Indexed by Google Scholar.