Andréia Cristina Ruy 1, 2 , [email protected], Adalene Moreira Silva 1 , [email protected] , Walid El Koury Daoud 2 , [email protected] , Jad Salomão 2 , [email protected] , 1 Instituto de Geociências-UnB, 2 Verena Mineração Ltda. The geology of the Volta Grande propierty, located in Para State, Brazil, is related to metavolcanic and metassedimetary rocks of the Três Palmeiras Greenstone Belt with two elongate diorite intrusions, known a North Block and South Block approximately 5 km away. The mineralization is hosted by both intrusions wich are trending NW and size 8 Km long by 1 Km wide. In the North Block, wher e most of the work was carried out, the gold mineralization is found in the steeply dipping shear zone system close to the contact zone of the intrusion with basic rocks of the greenstone belt. Gold resources are 68Mi t @0,93 g/t with cut-off 0,5 g/t (2,029Mi Oz of gold), based on 33792 m of drilling holes, reported by Wilson RPA, from Toronto, Canada and complaint with the NI-43101 standards (Feb 2008). Verena Mineração Ltda holds 100% of the concessions. Figure 01- Regional geological setting extracted from Altamira 1:250 000 scale (SA-22-Y-D) (CPRM, 2001) The red polygon represents the area covered by airborne geophysical survey. The interpretation of the geophysical data pointed out new target areas which were confirmed by geological and geochemistry approaches (Figures 4.1 and 4.2). Based on geophysical interpretation, where high K, Th and U concentration occurs, a soil geochemistry was carried out confirming Cu,Fe,ETR anomalies and generating a new IOCG target named Ituna (Figure 5). RGB (KThU) DZ -First Vertical Derivative ASA -Analytical Signal Amplitude Several geophysical maps that delineate highly prospective areas were derived. In regional prospective terms, the geophysical products convincingly map important host rocks units. More importantely, they predict new prospective targets in each of the different mineralized environmets, inside and outside the known mineralized areas with potencial to contain similar mineralization. Volta Grande (1:100 000) Geological map based on geophysical interpretation Radiometric Domains Structural/Magnetic Domains Figure 2 – Geophysical fluxogram: 2a.to 2c: geophysical products, 2d:Interpretation for integrated for geophysical and geological data. The Volta Grande airborne magnetic gradiometry and gamma spectrometric data (2007) were acquired using 200 m spaced north-south flight lines with orthogonal tie lines flown every 2,000 m at 100 m of constant ground clearance. The interpretation of magnetic and gamma-spectrometric data allowed the discrimination of several litho-structural domains (Figure 2d), the signature of main host rocks and hydrothermal alteration zones. An important interpretation of the Volta Grande area was achieved from visual analysis of the ternary radioelement map (Figure 2c) and the analytical signal amplitude map (Figure 2a). This map highlighted the key host rocks in the area: granodiorite and diorite (Figure 3.1 and 3.2). The high resolution airborne geophysical data mapped the favorable settings for the known mineralization (Grota Seca and Pequi target areas) that represent a combined structural and lithologic factors. Favorable structural settings are linked mainly to the rheological heterogeneities in the host sequences. The magnetic data allowed to map shear zones and faults developed along lithologic contacts between units of contrasting competencies. 2a 2b 2c 2d Figure 3- 1) South block showing the granodiorite mineralized area; 2) North Block showing the diorite host rock and the Grota Seca mineralization, 3) High K, Th and U anomaly mapped in the 2007 fieldwork as a IOCG target. Figurea 4.1 and 4.2 - Geophysical and soil geochemistry integration, showing the coincident anomalies. The best grades of Au zones are associated to thecontact of diorite and metavolcanic rocks, along the NE/SW direction. Figure 5 - 1) High K,Th and U and 2) Regional magnetic anomaly showing a new target named Ituna. Au(ppb) Au(ppb)