Sociodemographic attributes and dependency on artisanal and small-scale gold mining: The case of rural Gorontalo, Indonesia
The objective of this research is to investigate the livelihoods of villagers of rural Gorontalo, where limited job opportunities and poor infrastructure impede improvements in rural settlements. The research focused on rural regions where small-scale gold mining (ASGM) activities are prevalent in the economy. Given the associated complexities of the livelihoods of the villagers, the paper pays particular attention to household income and its sources and then examines associations with key socioeconomic variables, focusing especially on the contribution of educational development. The questionnaire survey was conducted among households in five villages of rural Gorontalo in August 2017, and 310 effective samples were collected. The results indicate that more affluent households receive a higher proportion of income from formal public sectors, such as government institutions. The source of income from mining accounts for approximately 20%, which is almost constant across the income quartiles. Fractional logit models were employed to examine the dependency of household income on mining. The estimation results indicate that educated households depend less on mining income than do uneducated households. Households with young household heads receive less income from mining than do those with old household heads. The paper implies that low educational attainments are related to a higher dependency on mining, probably due to limited job opportunities in the formal sector. Therefore, improvements in educational attainment are associated with a reduced dependency on the mining sector. The results yield key information for formulating policies for remote villages where a substantial improvement in rural livelihoods is pivotal to reduce dependency in the context of poor ASGM regions.
Komatsu, S., Tanaka, K., Sakakibara, M., Arifin, Y. I., Pateda, S. M., & Manyoe, I. N. (2020, November). Sociodemographic attributes and dependency on artisanal and small-scale gold mining: The case of rural Gorontalo, Indonesia. In IOP Conference Series: Earth and Environmental Science (Vol. 589, No. 1, p. 012020). IOP Publishing.
Sediment material potential of Bone River as a prevention of silting and flood of Bone River estuary, Gorontalo
Bone River estuary. Sediments are transported by river currents towards the estuary and Gorontalo Bay.
Bone River Estuary acts as a connecting lane between the three rivers (Bolango River, Bone River, and Tamalate River) with Tomini Bay. There is a port activity of goods located right on the river estuary, which is potentially disrupted due to the silting and can cause flood. This situation will undoubtedly disrupt port transportation routes and affect the economic condition of Gorontalo. The aim of this research is to identify the potential of sediment utilization at the downstream of the Bone River as an effort to prevent siltation at the estuary of river Bone, Gorontalo and to prevent flood. The method used in this research is field observation which includes observation of the morphological condition of research location and sampling. Samples will then be processed by means of sieving, separation, and classification of Sphericity sediment material by referring to zoning classification and Sneed and Folk classification. The result of histogram data showed that the sediment material was dominated by coarse sand size and grain size distribution dominated by coarse sand with size of phi is 0, on sediment data showed generally very leptokurtic with skewed skill or highly skewed.
Napu, S. S. S., Salama, T. H., Manyoe, I. N., Usman, F. C. A., Samir, I., Badaru, A. W. W., & Sugianti, K. (2020, November). Sediment material potential of Bone River as a prevention of silting and flood of Bone River estuary, Gorontalo. In IOP Conference Series: Earth and Environmental Science (Vol. 589, No. 1, p. 012003). IOP Publishing.
Geology and 2D modelling of magnetic data to evaluate surface and subsurface setting in Bongongoayu geothermal area, Gorontalo
Preparation before data acquisition.
Bongongoayu is one of the regions in Indonesia that has geothermal potential. Bongongoayu requires surface and subsurface data to support the preliminary data. This research aims to determine surface and subsurface data conducted by geology and magnetic method. The surface data, including geomorphology, lithology, hydrology and manifestation. The subsurface data have taken by the magnetic method. The result showed that the geothermal manifestation of Bongongoayu is a hot pool. The surface temperature is 43 to 59 °C. The geomorphology units is composed of volcanic hills unit and lake plains unit. The lithology of the research area is composed of granite and alluvial deposits. Based on petrographic analysis, the level of alteration in granite rocks is 65% and is classified as moderate alteration. The recharge area is in the north and southwest of the research area. Discharge area is in the central area. Based on 2D magnetic modeling, there are two subsurface layers. The first layer is alluvial and the second layer is granite. Rocks that are under the alluvial layer and have been altered are interpreted as a cap rock. 2D magnetic models show normal faults in the research area as a controlling factor for geothermal fluid.
Manyoe, I. N., Suriamihardja, D. A., Irfan, U. R., Eraku, S. S., Napu, S. S. S., & Tolodo, D. D. (2020, November). Geology and 2D modelling of magnetic data to evaluate surface and subsurface setting in Bongongoayu geothermal area, Gorontalo. In IOP Conference Series: Earth and Environmental Science (Vol. 589, No. 1, p. 012002). IOP Publishing.
Chemical content analysis of coral limestone as prospecting of extractive development in Gorontalo City
The potential of limestone in Gorontalo City is very large and distributed over a wide area. This enormous potential has not yet been exploited. This study aims to determine the chemical content of limestone and the use solution of limestone to improve regional development. Field data collection was carried out in two places, namely Tanjung Keramat and Buli'ide. Sampling was conducted at the coordinates N 0°29'38.93'' and E 123°2'49.62'' for station 1, N 0°32'53.7'' and E 123°1'56.19'' for station 2. The method used in this research is chemical composition analysis using X-Ray Fluorescence (XRF). The results of the analysis of the chemical constituents of Coral Limestone are CaO 83.35%, Fe2O3 6.92%, SrO 9.35% and ZrO2 3.25%. The prospect of Coral Limestone can be used in various industrial fields. Coral Limestone can be used in the mining industry, the cement industry, the sugar industry, ceramic raw materials, building materials, agricultural and road stabilizers. This indicates that the City of Gorontalo has the prospect of development and utilization of limestone resources available, in order to encourage self-reliance and open employment for community.
Annisa, W., Manyoe, I. N., Mubarak, A. K., Napu, S. S. S., Pratama, I. G. S., & Fatimah, S. (2020, November). Chemical content analysis of coral limestone as prospecting of extractive development in Gorontalo City. In IOP Conference Series: Earth and Environmental Science (Vol. 589, No. 1, p. 012021). IOP Publishing.
Gorontalo Outer Ring Road (GORR) road section
Gorontalo infrastructure development focus on improving transport efficiency through the development of Gorontalo Outer Ring Road (GORR). The Government has set the cost 750 billion rupiahs for GORR and planned will be completed by 2019 but constrained by landslides. This research aims to reconstruct and identify the type and mechanism of a landslide at GORR. The result of this research is landslide type and mechanism in the research area. The method used is 2-dimensional electrical resistivity sounding with Wenner-Schlumberger configuration. Landslide mechanism is analyzed based on the resistivity value table on Vingoe resistivity value supported by geological data. Based on geophysical data, subsurface conditions showed blocks of limestone with a resistivity value about 132 ohm.m and marked red-purple colors. These blocks of limestone interpreted as the result of the weathering process and buried in weathered clastic limestone. Landslide movement type is sliding movement and concluded as a rockslide. There is a potential for subsurface landslide blocks occur caused by the weathering process on fractures in the research area. The future prevention steps are by increasing the surface water absorption by planting in the geotextiles or prevent water infiltration in the landslide area. In addition, manufacturing retaining wall is also required.
Usman, F. C. A., Manyoe, I. N., Duwingik, R. F., & Kasim, D. N. P. (2020, November). Geophysical survey of landslide movement and mechanism in Gorontalo Outer Ring Road, Gorontalo. In IOP Conference Series: Earth and Environmental Science (Vol. 589, No. 1, p. 012008). IOP Publishing.