Berkeley currently has uranium exploration licences and applications in Spain that total over 150,000 hectares, including those associated with the Salamanca Project.
Whilst the Salamanca Project is the Company's main focus, progress has been made in collating, validating and interpreting data on past exploration work elsewhere in Spain, including prospects in the Cáceres, Badajoz, Toledo and Barcelona Provinces.
Uranium in Spain occurs in three main geological settings:
- Vein Deposits: Hosted in Pre Hercynian meta-sedimentary and granitic rocks (these include the deposits of the Salamanca Project)
- Sandstone Deposits: Hosted in Permo-Triassic fluvial sediments
- Lignite Deposits: Hosted in Tertiary basins
Berkeley has investigated the potential of these three deposit types and applied for exploration licences where potential for significant uranium resources may exist. Many of these tenements are still to be granted. These include Don Benito in the Badajoz Province, Lucena in the Toledo Province and Calaf in the Barcelona Province.
The Saguazal area is located in the Cáceres Province approximately 140km south of Retortillo. It is located within the Cabeza de Araya Hercynian granite which intrudes the late Precambrian Schist Greywacke Complex, similar to that within the Salamanca Project. Numerous uranium occurrences are associated with this granitic intrusion.
Previous uranium exploration in this area has been undertaken by JEN, ENUSA and CISA (a joint venture between COGEMA (now AREVA) and ENUSA) intermittently from the 1960's through to 1994. JEN was successful in discovering and mining the small La Zafrilla deposit which is located approximately 10km southeast of Saguazal, within the same granite intrusion.
Saguazal occurs in the central part of the batholith and was drilled in the early 1990's and a number of significant high grade intersections close to surface were reported. Ground radiometric surveys show the main Saguazal mineralised zone has the potential to be extended.
Berkeley has completed a diamond drilling program which intersected encouraging mineralisation including (results reported at a 200ppm U3O8 cutoff):
- 3.5 metres at 506ppm U3O8 from 15.0m
- 0.5 metres at 590ppm U3O8 from 5.3m
- SAG-0048.4 metres at 372ppm U3O8 from 12.3m
- 10.0 metres at 362ppm U3O8 from 13.0m
The mineralisation appears to occur in a sub-horizontal zone and is associated with breccias containing sulphides (pyrite/marcasite). No significant wall rock alteration is observed and zones of K-feldspar alteration, although radiometrically anomalous, contain little uranium. The mineralised breccias may be controlled by shallow, north-dipping structures, the base of which is marked by a clay pug zone.
The Calaf tenements cover an uranium-bearing Tertiary lignite coal deposit within the Barcelona Province in Eastern Spain.There are three main lignite coal seams up to 3.5m thick and up to 150m below the surface. The coal has a moderate thermal value (averaging 4,300 kcal) and contains between 225ppm to 660ppm U3O8. Assessment of this project by Berkeley is in its very early stages and tenements are yet to be granted.
To date all known uranium deposits have some surface expression and it is expected that mineralisation will also occur in the extensive areas of Tertiary cover. Berkeley is undertaking ongoing studies to better understand the geology and structure of the uranium mineralisation. Information from these studies will assist in better defining the ongoing regional exploration effort, including targeting areas under Tertiary cover where standard radiometric surveys are ineffective.
Regional studies also continue to define new areas for potential uranium resources.