Bonanza’s Great Basin Metallogenic Exploration Study represents a technical breakthrough similar in potential to past exploration advancements such as the application of electro-magnetic geophysical techniques to exploration for volcanogenic massive sulfide deposits, and the application of the porphyry copper genetic model. The Study is based on the theory that if one can determine how high grade gold deposits are formed, and identify the structural and geological conditions required for the formation of these deposits, then one should be able to predict the location of other, undiscovered deposits by analyzing structural and geologic conditions.
The software used to manage and analyze these regional exploration data is the Arcview Geographical Information System (GIS). The GIS is a two-dimensional environment, and is useful on a regional scale and on a project scale for surface information such as surface geochemistry and geologic mapping. The database includes basically all publicly available data published in digital form, including geology, structure, land/legal, physiographic, geochemical and geophysical data on the Bonanza Properties and on other mining properties in Nevada.
The proprietary databases include a seven-volume set of large 3-ring binders describing in detail 44 operating major mines in Nevada. This database is part of the GIS database, and allows vetting of exploration concepts against known deposits, and the generation of structural models for gold deposits. Public data augment these detailed mine data, thus over 100 mines are represented in the database, representing a comprehensive view of nearly all important modern mines in Nevada. Another comprehensive proprietary database describes 571 modern gold resources in Nevada. Essentially all of the historic underground high grade mines in Nevada comprise another proprietary database. Over 1,430 old mines in Nevada produced gold as the primary product. Nearly 4,000 historic mines comprise the database, many of which produced some gold in addition to other metals. Numerous other proprietary geochemical and structural databases have been developed by Bonanza.
The GIS database was used by Bonanza to unravel the geologic history of the Great Basin during and prior to the time of the formation of gold deposits. The structural interpretation of the western North American continental margin over the past 100 million years predicts detailed relationships between local structure and gold deposits. An exhaustive review of the mine-scale structure and gold mineralization supports the continental structural interpretation developed by Bonanza’s personnel. Bonanza’s metallogenic study is a study of the formation of gold deposits in the Great Basin. The study is a predictive tool for prospecting and the evaluation of properties.
All of Bonanza’s projects have been modelled using the three-dimensional environment of the SURPAC mine planning software program prior to drilling. All surface and subsurface data are entered into SURPAC software to guide drilling programs. Surface data generally include topography, air photo images, sampling results, mapping, etc. Subsurface data include (where available) existing drill data, mapping and sampling data from existing underground workings, and extrapolations of the surface data. In the SURPAC three-dimensional environment, precise drill plans are generated by working with the actual surface and subsurface data.
Once drill targets have been drawn from the three-dimensional model, SURPAC provides a report containing surface co-ordinates and elevation of the drill collar, along with bearing, inclination and total depth. This approach provides the accurate drilling plans required to efficiently explore high grade gold bearing vein systems.