Hungry Gully Project: technical data
The Project: Rodinia Jamaica Limited (“Rodinia”), which is 100% owned by Carube Resources Inc of Canada, has a 100 percent interest in the 48 km2 Hungry Gully Special Exclusive Prospecting License (“Hungry Gully" or “SEPL 559"). Hungry Gully is located on the very southern edge of Cretaceous Blue Mountain Inlier (Map 1); the Plantain Garden Fault crosses the southern edge of the SEPL and marks the southern edge of Inlier. The southwest part of the Blue Mountain Inlier has been subjected to compressional forces leading to significant uplift and exposure of once deeply buried Cretaceous metamorphic rock units, including the Mt Hibernia Schist, which underlies most of the Hungry Gully property.
Stream sediment sampling by the Canadian International Development Agency (“CIDA”) and follow-up soil and rock sampling by BHP has identified two possible areas of copper and gold mineralization at Hungry Gully. The soil anomalies cover broad areas at Round Hill and Dunrobin. Out of a total of 1682 soil samples collected by BHP, 36 samples exceeded 100 ppb Au with a maximum of 1.5 g/t Au and 41 samples exceed 225 ppm Cu with a maximum of 0.45% Cu.
Prior to further drilling or trenching at Hungry Gully, magnetic and radiometric surveying, infill soil geochemical sampling, and detailed mapping are recommended at Round Hill and Dunrobin to (i) determine the nature and trends of mineralization present and (ii) guide drilling and trenching programs.
Geology and Mineralization
Regional Geology: Jamaica is a part of the Greater Antilles island arc system, situated on the northern Caribbean Plate margin, which is sliding eastward along the North American Plate (Map 3). Hispaniola, Puerto Rico and Jamaica all lay on the northern margin of the Caribbean Plate. Most geologists believe that the three islands have similar stratigraphy and metallogeny, which opens the potential for porphyry Cu deposits in Jamaica similar to those in Puerto Rico and major gold deposits, such as Pueblo Viejo in the Dominican Republic. Jamaica is an emergent part of the Nicaraguan Rise, a broad, anticlinal, dominantly submerged belt of crustal thickening extending from Honduras to east of Jamaica.
Jamaica itself is comprised of three major groups of rocks:
The Cretaceous basement complex consists of volcanic, volcaniclastics and associated intrusive and coarse clastics. It is believed that the volcaniclastics represent an eroded island arc system. At the end of the Cretaceous period, the basement was uplifted, resulting in an unconformity making the Cretaceous-Tertiary boundary.
The Tertiary white and yellow limestones, unconformably overlying the Cretaceous basement complex and conformably overlying Cretaceous trough sediments, cover approximately 70% of the island. Intrusive activity was confined largely to the Cretaceous, Paleocene and Miocene, with major deformation occurring during the early Tertiary.
In areas where the limestone cover is breached, the older sedimentary, igneous and metamorphic rocks are exposed through windows known as inliers. There are seven major and twenty-one minor inliers on Jamaica. The three largest are the Blue Mountain the Central, and the Lucea Inliers. The Blue Mountain Inlier is 42km by 22km and lies in eastern Jamaica. It is bounded to the west by the Wagwater trough and to the south by the Plantain Garden Fault which extends west onto Hispaniola.
Blue Mountain Inlier Geology: The Blue Mountain Inlier contains some of the oldest rocks—and some of the only metamorphic rocks—in Jamaica, namely a unit of Mesozoic schist known as the Mt. Hibernia Schist (Map 2). The metamorphic rocks are in fault contact with surrounding un-metamorphosed Cretaceous rocks, which consist primarily of non-distinct, heavily weathered, fractured and hydrothermally altered volcaniclastic and andesitic volcanic rocks with minor limestones that are variously assigned to the Bellevue, Plantain Garden and Blue Mountain formations. The Mt Hibernia Schist is dominated by aphanitic, lightly fractured greenschist and blueschist rocks subject to weak retrograde metamorphism. Minor constituents include marble, partially serpentinized peridotite and riebeckite-bearing metachert.
The left-lateral Plantain Garden strike-slip fault, a late Cenozoic tectonic feature, cuts across the south part of the property, separating the Blue Mountain Inlier from marine turbidites of the Paleogene Richmond Formation. The close spatial association of the metamorphic rocks with the fault suggests that the rocks were uplifted as a result of compression at a restraining bend along the fault. The rocks were likely initially deformed and metamorphosed in the lower part of an Early Cretaceous island-arc accretionary complex at depths of greater than 20 km. Late Cenozoic convergence was manifest by topographic uplift (>2 km), rapid erosion, and northwest-southeast shortening of Cretaceous and Paleogene metamorphic, volcanic and sedimentary rocks in the Blue Mountains. Limited data on the age of faulting in Jamaica suggest that the tectonic activity probably began in the middle to late Miocene and was roughly contemporaneous with initial strike slip along the eastern extension of the Plantain Garden fault zone in southern Hispaniola.
Blue Mountain Inlier Mineralization and Alteration: The nature of deposit that has led to the geochemical anomalies at Round Hill and Dunrobin is difficult to ascertain as no recorded trenching has been completed and drill-core recovery was poor. Likely significant deposit types given the geological setting and results from geochemical soil surveying are:
Identified Mineralized Trends: In 1986, the Canadian International Development Agency (“CIDA”) collected ~3000 stream sediment samples over the Cretaceous Inliers across Jamaica. Results showed a large copper anomaly with associated gold centred on Hungry Gully (Map 3), which was described as “arguably the most coherent copper-gold stream anomaly” generated from the entire CIDA program. The two stream sediment samples from Hungry Creek returned values of 997 and 230 ppb Au. CIDA designated a Priority 1 Au–Cu target where the Mt. Hibernia Schist was in contact with younger Cretaceous volcanics. Chris Gleeson reanalyzed the CIDA data and interpreted a large gold anomaly that overlaps part of the Priority 1 CIDA Au-Cu target (Figure X).
HISTORIC EXPLORATION AT HUNGRY GULLY
CIDA Surveys: In 1986, the Canadian International Development Agency (“CIDA”) collected ~3000 stream sediment samples over the Cretaceous Inliers across Jamaica. Results showed a large copper anomaly with associated gold centred on SEPL 559, which was described as “arguably the most coherent copper-gold stream anomaly” generated from the entire CIDA program. The two stream sediment samples from Hungry Creek returned values of 997 and 230 ppb Au. CIDA prioritized all individual anomalies within the Blue Mountain Inlier and listed three within SEPL 559, including a Priority 1 Au–Cu target where the Mt. Hibernia Schist was in contact with younger Cretaceous volcanics. Gleeson (1991b) reanalyzed the CIDA data and interpreted a large gold anomaly that overlaps in part with the Priority 1 CIDA Au-Cu target.
In addition, Rodinia Jamaica ltd reprocessed results from a CIDA geophysics program; the edge of a NW trending magnetic high traverses the SEPL and a broad residual gravity high marks the central part of the SEPL (Map 6)
BHP Soil Sampling: BHP collected 1682 ridge and spur soil samples in the early 1990s to follow up on the CIDA Priority 1 Au-Cu anomaly. Thirty seven of these were >100 ppb Au, including a peak value of 1500 ppb Au at Round Hill. One hundred of the soil samples yielded >200 ppm Cu, with a peak soil anomaly of 4500 ppm Cu. BHP also collected abundant (i) rock samples, but nature of the samples was not reported and (ii) stream samples, but the locations and analytical results are not known.
BHP Rock Sampling: It appears that BHP collected rock samples. Locations for about 2000 samples are available and their notation (RG for rocks (?) vs. SG for soils) would suggest the RG samples are rock samples (probably weathered). The higher metal values relative to those of adjacent soil samples suggest that they were collected at a greater depth than the soil samples. The layout of some in short straight lines suggests samples from a trench. The numerous samples taken along “walking trails” suggest that holes were dug or augured to resistance in weathered bedrock. Soil and weathered rock (?) samples are useful in assessing nature and trends of mineralization.
BHP Drilling: BHP drilled four holes on Round Hill. All of the holes were shallow (<115 m deep) and had poor diamond drill hole (DDH) core recoveries (<50%). Mainly clay and chlorite altered basalt and sediments were noted in the DDH logs by BHP. Assay results are shown in Table 1. No copper results were reported by BHP. The exact locations of the drill holes are unknown; complete core logs are not available. Reported intersections are reported below.
There has been no mining activity at Hungry Gully.
PLANNED EXPLORATION PROGRAMS
Strategy: At Hungry Gully Carube intends to further investigate the two anomalies discovered to date in order to define the type of mineralization present and thereby optimize further exploration of these targets. With some of the highest anomalies and fragmented past exploration, a systematic approach to exploration will likely create multiple large attractive targets for trenching a drilling.
Action: In order to determine those near-surface high grade showings and prospects, Carube has initiated a program to collate the remainder of the BHP data. Upon the completion of this, detailed mapping and rock sampling will need to be conducted and infill geochemical soil sampling be completed at Round Hill and Dunrobin and integrated into the present soil sampling to determine the nature and trend of the mineralization there. Prior to any trenching and drilling campaign a soil sampling program at Home Hill should be initiated to determine the direction and nature of mineralization on this untested CIDA anomaly. This needs to be supplemented by magnetic and radiometric surveys before the drilling or trenching is completed.