c 62 report

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1 LIST OF CONTENTS Page . Introduction 3 Location and Access 3 Previous Work 4 Previous Work by the Geological Survey 4 Geophysics 5 Mineral Occurrences 6 C-62 Area Geology 7-8 Comments & Conclusions 8 References 19

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Page 1: C 62 Report

1

LIST OF CONTENTS Page .

Introduction 3

Location and Access 3

Previous Work 4

Previous Work by the Geological Survey 4

Geophysics 5

Mineral Occurrences 6

C-62 Area Geology 7-8

Comments & Conclusions 8

References 19

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List of Figures

Page

Figure 1. Location Map 9

Figure 2. Gold Geochemistry Summary map 10

Figure 3. Mineral Occurrence Summary Map. 11

Figure 4. Geological Summary Map 12

Figure 5. Geological Summary Map 13

Figure 6. Geological Summary Map. 14

Figure 7. Geological Summary Map 15

Figure 8. Geological Summary Map 16

Figure 9. Aeromagnetic Map 17

Figure 10. Topographic Map 18

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Introduction

The Prospecting Licence (C-62) located in the Mazaruni Mining District No. 3 as shown

on Terra Surveys Topographic Map 35SW, as shown in fig 10 and enclosing an area of

approximately 10947 acres of the Hubana River. The potential of the area for gold

diamond and is very good.

The Kuribrong area where this concession is located have been subject to an

abundance of activity from small scale artisan prospecting up to large scale multi-phase

exploration programs initiated by Guyana Geology and Mines Commision.The entire

concession encompasses what is identified as Hubana Goldfied.

Several areas within the concession have been mined for gold and diamonds in the past by

pork Knockers, starting 1898.

The geology of the area consists of Lower Proterozoic Mazaruni Supergroup (greenstone

belts) consisting of meta-sediments and meta-volcanic rocks, intruded by Younger Granites.

Unconformably overlying these rocks is the Roraima Formation, a generally flat lying series

of conglomerates, sandstones, shales and with minor interbedded volcanics. All of these

rocks (greenstones, granites, and post-orogenic sedimentary series), are intruded by

doleritic and gabbroic dikes and sills (the Younger Basic Intrusive Suite).

Location and Access

The concession (C-62) is located in the Potaro Mining District, approximately 180 km SW of

Georgetown, and comprises the catchments of the Hubana River. Access to the

Concession is either from Georgetown to Bartica via speed boat on the Essequibo River, or

by road from Georgetown to Linden (81 km) to the Sherima Ferry crossing (55 km). From

Bartica, the Issano Road leads to the Sherima Ferry Crossing (41 km) and then to Mile 72

(92 km). There is also a small dirt road that by-passes the crossing and connects the Issano

Road below the crossing. Continuing on the Issano Road from Mile 72 to Apanachi (46 km),

leads to an old trail that was rehabilitated for truck and 4-wheel drive access to Powis

Landing (19km).From Powis Landing on Kuribrong River,the concession can be access by

boat. Almost all basic supplies, such as fuel and food can be obtained in Bartica.

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Previous Work

The area has a long history of localized, small-scale gold production, as far back as in

the 1930s and 1940s. The surrounding region of the Hubana River-Kuribrong River is

acknowledged for its gold production, whether it is from river dredging, land dredging or

land excavation. Historically and currently there has been an abundance of small to

medium scale gold and diamond operations. Gibbs (1971) reported that gold mining

activity was intense during the period 1898-1940.

Previous Work by the Geological Survey

Work began in the area with river traverses in 1875 (Gibbs, 1975). Throughout the late

1920’s and 1930’s numerous investigations were made by Connolly, Bracewell, Grantham

and Williams (Connolly and Bracewell 1928; Bracewell, 1944). These studies focused on

surficial deposits and prospecting for alluvial deposits of gold and diamonds, but their maps

also showed significant bedrock classification, and were the first to record the stratification

that has remained in use today. Reports detailed geographic relationship of bedrock

lithology to topography, surficial deposits and alluvial mineralisation. On a more regional

scale, Bateson, J.H., and Allderidge, M.G (1961) reported on the geology of the area

bounded by the Mazaruni, Kaburi, Waiamu, Hubana, and Kuribrong Rivers. They described

the major rock types and concluded with a stratigraphy unchanged from that discerned by

previous workers in the 1920’s. However, they provided further interpretation on the source

of gold mineralisation in the area and suggested that quartz veining accompanying intrusion

of granites (and diorites?) concentrated gold in bedrock.

Page 5: C 62 Report

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Geophysics

The area is covered by a summary aeromagnetic data survey in digital form from the British

Geological Survey, and paper 1:200,000 scale aeromagnetic contour maps are available.

The simplest level of interpretation was used – studying visual patterns, correlating belts of

highs and lows and superimposing existing geological, topographic and aeromagnetic

maps, as well as previous interpretation maps by earlier workers.

The aeromagnetic data shows distinct areas with magnetic highs, or abrupt magnetic

gradients. Meta-basic rocks are often magnetic in hand-specimen, but also form distinct

topographic highs. Known areas of meta-basic rocks match well with the disturbed /

magnetic high areas, though this may be partly due to ground effects.

The Younger basic rocks surprisingly do not form distinct magnetic anomalies, though basic

rocks are normally magnetic, and known basic dykes form distinct topographic features.

Even reversed magnetised bodies are expected to reveal high gradients at the edges.

Known areas of Younger Granites correlate with magnetically quiet like Hubana the

concession area.

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Mineral Occurrences

Gold

The central portion of the concession contains a number of known Alluvial mineralisation

and gold anomaly occurrences. Data is derived from a combination of the USGS MRDS

(Mineral Resources Database System), GGMC maps and reports and fieldwork. The

location of known mineral occurrences is shown in Figure 9. Digital data is divided into 2

files. The Guyana Mineralisation File is based on the original USGS MRDS, with improved

co-ordinates and updated information, and new mineral occurrences about which more than

minimal information is known. The Alluvial Minerals file is used for additional alluvial mineral

occurrences derived from spots marked on historical GGMC maps, or abandoned dredge

sites seen in the field for which additional information is not available. Many of the sites

shown in Figure 9 are derived from geological maps produced by Gibbs, et. al., 1971 & 1972

and a report by Gibbs (1973).

In the Kuribrong-Hubana area 14 gold mineral occurrences from the Guyana Mineralisation

file occur. A few of these are currently being mined on a small scale by “land dredges”.

Several areas in creeks headwaters may be related to primary mineralisation, or gold

derived from white sand basal gravels of which Hubana is one such creeks. At Lower

Hubana extensive pitting occurred over a one mile flat area. Almost continuous creek bed

excavations were worked along this creek flowing east 1.7miles from the Hubana Mouth.

Geology consists of high laterite capped hills of basic volcanics and meta-volcanics. Rocks

are reported to contain small quartz stringers and threads; larger veins were not seen.

Persistent fair values (50-100 eyes / battel) were seen in the region of basic volcanic south

of the creek.

.

Page 7: C 62 Report

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C-62 Area Geology

The rock units are discussed in order of perceived age, oldest first. The discussion that

follows is summarized from Gibbs (1973 and 1975), Keats (1973), and Bracewell (1944).

These authors provide consistent summaries of the geology of the project area. Figure 8

and Enclosure 4 illustrate the distribution of different units in the area.

Generally, the geology of this area is very similar to that seen in other parts of the

greenstone belts of Guyana, with the oldest rocks consisting of the Lower Proterozoic

Mazaruni Supergroup, intruded by Younger Granites. In the western part of the area, these

rocks are uncomformably overlain by Roraima Formation, a generally flat lying, post-

orogenic series of conglomerates, sandstones, shales and volcanics. All these units are

intruded by Younger Basic Rocks.

Meta-Basic Rocks.

Meta-basic rocks consist of 1) metamorphosed gabbroic or doleritic dikes and 2) epidiorites

and amphibolites. One meta-basic gabbroic dike occurs in the project area, in the central

portion. It intrudes meta-volcanic rock and is offset by a northeast trending fault.

Amphibolites generally occur in contact zones around the larger Younger Granitoid

Intrusions. In general, these outcrops form low hills often capped by laterite duricrusts

Meta-volcanics.

Meta-volcanic rocks in the area have a varied composition, though most samples examined

petrologically were acid meta-volcanics. Bracewell (1944) reported that the rocks exist in a

belt that strikes NW across the Kuribrong area extending from the Hubana River mouth to

Embiparu Falls (about 5 km downstream in the Kuribrong River). This same belt appears on

the Gibbs et. al., (1971) maps. Gibbs (1975) noted pillowed exposures and water-lain tuffs

that supported a submarine origin for the volcanic rocks, as well as siliceous volcanics and

associated agglomerates that were probably once centres of volcanic eruption.

Page 8: C 62 Report

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Meta-sediments

Bracewell (1944) described white sericite schists and green chlorite schists in the area

and suggested that these rocks were probably metamorphosed argillaceous

sedimentary beds. Gibbs (1975) described the series as grey graded greywackes and

shales, with ferruginous cherts

Comments & Conclusions

Based on the body of data in this concession, further exploration activity is warranted.

Mapping suggested that at least some of the gold was derived from superficial white

sand cover. Gold recent geochemistry data is in agreement with previously known gold

mineralisation areas,as shown in fig 3. This indicated that the stream sediment

samplying was done well.

Detail soil sampling and gological mapping is required to accurately define the grade

and type of mineralization but from the sampling and study undertaken it can be

suggested that gold mineralization is hosted in quartz veins and quartz rich lodes in this

area.Further work to better understand the geology in this concession should be

undertaken as there may be a significant source of primary gold, which resulted in

alluvial deposits seen in the concession.

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Fig1, Location map

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Figure 2, Gold Geochemistry Summary map

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Figure 3, Mineral Occurrence Summary map

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Figure 4, Geological Summary Map

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Figure 5, Geological Summary Map

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Figure 6, Geological Summary Map

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Figure 7, Geological Summary Map

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Figure 8, Geological Summary Map

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Figure 9, Aeromagnetic map

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Figure 10, Topographic Map

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REFERENCES :

Cole, E.C., Heesterman, L.J.L. & Kemp, A.W. 2003. Kuribrong Project. A summary of geochemistry, geology and structure.Guyana Geology and Mines Commission, Geoservices Division Technical Report GS1/2003.

Gibbs, A.K. 1973. Notes to Accompany the Economic Geology map of the Potaro-Mazaruni District, Guyana.

Bateson, J.H., and Allderige, M.G., 1958, Geology of the area bounded by the Mazaruni, Kaburi, Kuribrong and Waiamu Rivers, GGMC unpublished report, maps P5/F2/8 and P5/F2/10, 17p.