It is very important to understand geological structure very well for planning of drilling program and geothermal reservoir management for operational and new geothermal development area. Therefore it is necessary to be easy to be able to understand image of underground structure by 3D visualization and analysis by making database by compiling huge amount of existing exploration data efficiently, if necessary, by converting non-numerical data to numerical data.
This paper reports the case study of 3D geological structuring modelling and planning of exploration wells in the Ogiri area located at the foot of the Kirishima volcanos, Kagoshima Prefecture, by compiling existing geological survey data, geophysical data, drilling data etc. into the database of “VULCAN”, which is a 3D visualized geological modelling software developed in Australia for mine operation and mine development planning, and nowadays on public sale.
In the Ogiri area, the government and some private companies have conducted surface geological surveys, geophysical surveys such as electrical and electromagnetic surveys and drilling surveys.
For the purpose of 3D visualization and utilization of huge amount of data obtained in the above surveys, various data and information such as location of existing drill holes, geological boundaries, contacts of fault planes, homogenization temperatures of fluid inclusions, estimated equilibration temperatures, magnetic susceptibility, were collected and compiled into database. As for un-numerical data such as alteration strength, distribution of alteration minerals, etc., were converted to numerical data, and compiled into database. As for geophysical image data such as cross sections of resistivity, cross sections of seismic reflection surveys, etc., such image data were also compiled into database. 3D geological modelling was conducted by using the constructed database.
As a result of such geological modelling, a geothermal target was extracted in the area where a few exploration drill holes exist, and the exploration drilling program was planned, and finally, we successfully intersected a geothermal reservoir at the estimated location in an exploration well. The result indicates improvement of accuracy of drilling program and possibility of efficient management of geothermal reservoir by applying 3D mining software “VULCAN” to geothermal field.

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Agency for Natural Resources and Energy had established a newsearching system based on Web GIS, called GRIAS, Geo-Resource Information Archive System, aiming to secure mineral resources including minor metals in 2014. This project started in 2009 and had been implemented for 5 years.
GRIAS will contribute to development of minor metals with satellite images of ASTER and PALSAR data.
GRIAS allows users to search resource information and infrastructure information related to metal resource development project over the base maps of global satellite analysis images.
Then users can select and display them and make a reconnaissance survey report, study feasibility and make an investment decision.
There are well known Google Earth / Map to show global satellite images through the web. But they don't contain geological or resource information. Australian governmental organization, CSIRO operates AuScope to provide geology, soil and environmental information in Australia only. On the other hand, GRIAS's satellite analysis images cover global earth and GRIAS is focusing all contents and functions to geological and resource information to secure minor metal resource supply to Japan.
The seamless mosaic which shows Earth surface features clearly without clear scene boundaries, was compiled from ASTER and PALSAR data. ASTER and PALSAR, as Earth observing sensors, have been developed and operated by Japanese governmental organization. Further useful satellite analysis images for geology and mining exploration had been created and registered on GRIAS. User can use GRIAS with only PC and Internet access. User's request hearing and system renovation cycle had been repeated, and new contents and functions were added on in order to improve usability.
GRIAS is scheduled to start operation in 2014 to support Japan's metal developers to secure minor metal supply.

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In October 2009, JOGMEC entered into a mineral exploration joint venture ("JV") agreement with Vancouver based Platinum Group Metals Ltd. ("PTM") and South Africa based Mnombo Weth Consultant CC to conduct a grass-rooted Waterberg PGE project at the north of the Bushveld Northern limb, South Africa. The project area is totally covered with Proterozoic Waterberg Group, a dense sedimentary package after Bushveld igneous complex intrusion, thus none has ever attempted PGE exploration due to lacking any mineral showings. The exploration target of the JV was deep-seated hidden PGE reefs suggested by high gravity and high magnetic features elongating NW to SE in the area.
After two-year detailed ground gravity and magnetic surveys and following two structural diamond drill holes ("DDH"), the third hole WB003 located southeast end of the area intersected significant PGE mineralization in Main Zone from 643.25m to 646.75m (3.50m) with an average grade of 3.47g/t [2PGE+Au], and 661.50m to 665.50m (5.00m) of 7.00g/t. Since following several holes surrounding to WB003 also intersected similar mineralization in the same igneous horizon, the JV confirmed that PGE mineralization occurs as a continuous "reef". Then, massive 250m-grid drilling campaign has been conducted up to September 2013. The JV completed 111 DDH of total 128,505 m length, and delineated 17.7million ounces (545t) of precious metals [Pt (163.3t), Pd (328.4t) and Au (53.3t)] under the inferred resource category. Further exploration room is still remaining in northward and in depth from the current resource area.
The JV concludes that Waterberg deposits consist of two new PGE reefs, shallower T zone and deeper F zone, both are dipping to west 34 to 38 degree, extending NNE-SSW which trend is different from JV's initial idea suggested by geophysics. Major ore minerals in both zones are mostly pentlandite and chalcopyrite. Pyrrohtite and pyrite are common in F zone but rare in T zone. The shallowest part of the T zone is 130m from surface which mostly consists of gabbronorite, anorthosite, troctolite and pyroxenite. Texture is coarse to pegmatoidal in part. Thickness of mineralization is 3.7m in average (T2 zone), swelling up to 25m. T zone is characterized by unusually high gold ratio of 20% in a metal split of Pt, Pd and Au, as a Bushveld PGE reef. Another deeper PGE reef, F-zone is an igneous horizon located 100m to 450m below the bottom of T-zone. F-zone mostly consists of troctolite and hurzburgite, rarely pyroxenite. Width and grade vary place by place, but its width tends to be greater than T-zone. F-zone occupies the lowest Bushveld igneous stratigraphy in the area contacting to meta-granite basement. Alteration minerals, talc and serpentine gradually increase with depth toward the basement boundary. On a metal split, F-zone ore shows high Pd contents of more than 60%, while Au contents are less than 5% that are common level in Bushveld PGE reefs.
Upon recently disclosed positive results of preliminary economic assessment of the Waterberg project, the JV is preparing the pre-feasibility study. Concurrently, JOGMEC plans to transfer its project interest to qualified Japanese company(s).

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