Reconnaissance Geochemical Survey for Uranium and Related Industrial Minerals in Cebu Island

PNRI B(EA)&

RECONNAISSANCE GEOCHEMICAL SURVEY FOR URANIUM AND RELATED INDUSTRIAL MINERALS IN CEBU ISLAND

Rolando Y. Reyes Angelito F. Ramos Wilfred N. Magsambol r,lmer C. Hernandez

March 1989

Philippine Nuclear Research Institute Diliman, Quezon City PNRI B(EA)89001

DPnAMMMCCAWPI? ^rnfiiFMTnAr uEAjUmjiiiunij SURVEY FOE OEAHIUB AND RELATED INDUSTRIAL MINERALS TM PCDTT TCT AMP

Rolando Y. Reyes Aneslito F. Ramos Wilfred N. Magsambol Elmer C. Hernandez

March 1989

Philippine Nuclear Research Institute Dill man, Quezon City PNRI (EA)89001

TABLE OF CONTENTS Page Abstract 1 1. Introduction 2 1.1 Purpose and Scope of the Report 2 1.2 Location and Accessibility 2 1.3 Climate, Vegetations and Culture 4 1.4 Previous Work 5 1.5 Present Fieldwork 6 2. Geology and Mineral Resources 7 2.1 Geomorphology 7 2.2 Lithology 9 2.3 Structures 13 2.4 Mineral Deposits 15 3. Procedures 16 3.1 Field Procedures 16 3.2 Analytical Methods 16 3.3 Statistical Treatment of Field and Analytical Data 17 3.4 Map Presentations 22 4. Results and Discussions 22 4.1 Scintillometer Survey 22 4.2 Stream Water Survey 24 4.2.1 Uranium 26 4.2.2 Radon 26 4.3 Uranium in Stream Sediments 29 4.4 Uranium in Heavy Minerals 31 PNRI (EA)89001

TABLE OF CONTENTS (cont'd) Page 4.5 Multi-Element Survey 33 4.5.1 Copper 34 4.5.2 Lead 37 4.5.3 Zinc 40 4.5.4 Manganese 40 4.5.5 Silver 46 4.5.6 Cobalt 46 4.5.7 Nickel 51 4.6 Correlation Between Elements 53 5. Conclusion and Recommendations 56 6. Acknowledgement 59 7. References 60 PNRI B(EA)89001

LIST OF FIGURES

Figure No. Page 1. Location Map of Cebu 3 2. Geology of Cebu 8 3. Scintillometer Readings 25 4. Uranium in Stream Water 27 5. Radon in Stream Hater , 28 6. Uranium in Stream Sediment 30 7. Uranium in Heavy Minerals 32 8. Copper in Stream Sediment 35 9. Copper in Heavy Minerals 36 10. Lead in Stream Sediment 38 11. Lead in Heavy Minerals 39 12. Zinc in Stream Sediment 41 13. Zinc in Heavy Minerals 42 14. Manganese in Stream Sediment 43 15. Manganese in Heavy Minerals 44 16. Silver in Stream Sediment 47 17. Silver in Heavy Minerals 48 18. Cobalt in Stream Sediment 49 19. Cobalt in Heavy Minerals 50 20. Nickel in Stream Sediment 52 21. Nickel in Heavy Minerals 54 22. Delineated Areas for Follow-Up Survey 57 PNBI B(EA)89001

LIST OF TABLES Table No. Page I. Summary Statistics Using Total Data. Preliminary Investigation on the Nature of Distributions .... 19 II. Summary Statistics Showing the Background and Threshold Values 21 III. Correlation Coefficient Matrix of Elements in Stream Sediments Based on 361 Samples 23 IV. Correlation Coefficient Matrix of Elements in Heavy Minerals Based on 154 Samples 23 V. Correlation Coefficients Between Stream Sediments and Heavy Minerals in each Element Bused on 154 Samples 55

LIST OF APPENDIX Appendix 1 Frequency Distribution of Uranium, Copper, Lead and Zinc in Stream Sediments Appendix 2 Frequency Distribution of Manganese, Silver, Cobalt and Nickel in Stream Sediments Appendix 3 Frequency Distribution of Uranium, Copper, Lead and Zinc in Heavy Minerals Appendix 4 Frequency Distribution of Manganese, Silver, Cobalt and Nickel in Heavy Minerals Appendix 5 Frequency Distribution of Radon and Uranium in Stream Hater and Scintillometer Readings Appendix 6 Scatter Plot of Nickel Versus Cobalt in Stream Sediments Appendix 7 Scatter Plot of Copper Versus Zinc in Stream Sediments Appendix 8 Scatter Plot of Manganese Versus Zinc in Stream Sediments Appendix 9 Scatter Plot of Manganese Versus Cobalt in Stream Sediments Appendix 10 Scatter Plot of Manganese Versus Nickel in Stream Sediments PNRI B(EA)89001 LIST OF APPENDIX (cont'd) Appendix 11 Scatter Plot of Zinc Versus Nickel in Stream Sediments Appendix 12 Scatter Plot of Manganese Versus Copper in Stream Sediments Appendix 13 Scatter Plot of Zinc Versus Cobalt in Stream Sediments Appendix 14 Scatter Plot of Nickel Versus Cobalt in Heavy Minerals Appendix 15 Scatter Plot of Zinc Versus Cobalt in Heavy Minerals Appendix 16 Scatter Plot of Zinc Versus Lead in Heavy Minerals Appendix 17 Scatter Plot of Cobalt Versus Silver in Heavy Minerals Appendix 18 Scatter Plot of Zinc Versus Nickel in Heavy Minerals Appendix 19 Scatter Plot of Zinc Versus Silver in Heavy Minerals Appendix 20 Scatter Plot of Nickel Versus Silver in Heavy Minerals Appendix 21 Scatter Plot of Zinc Versus Copper in Heavy Minerals Appendix 22 Scatter Plot of Copper Versus Lead in Heavy Minerals Appendix 23 Scatter Plot of Cobalt Versus Copper in Heavy Minerals PNRI B(EA)89001

RECONNAISSANCE GEOCHEMICAL SURVEY FOR URANIUM AND RELATED INDUSTRIAL MINERALS IN CEBU ISLAND by ROLANDO Y. REYES ANGELITO F. RAMOS WILFRED N. MAGSAMBOL ELMER C. HERNANDEZ ABSTRACT Consistent with the program of evaluating the nuclear mineral resource potential and related industrial minerals of the Philippines, a reconnaissance geochemical survey was conducted in Cebu with considerable success. The total area covered by the survey was about 5,088 sq. kms. The survey consisted of systematic collection of 857 geochemical stream sediment and water and heavy mineral samples, and measurement of radioactivity in over 352 stations. The average sampling density was about one set of samples per 15 to 30 sq. kms. All solid samples were analyzed for U, Cu, Pb, Zn, Mn, Ag, Co and Ni. Uranium, radon and conductivity were measured on most water samples collected. A total of 4,518 elemental determinations were involved. All field and analytical data were treated by statistics, and the computed parameters were correlated with the geology of the area to establish anomalous zones.

Four areas were delineated for possible uranium mineralization and several areas were also pinpointed for other possible metallic mineralization. Of the four areas, the Mandawe River area is the most interesting for uranium. The contact zone between the diorite and the sedimentary rocks in this area appears to be a favorable geological environment for uranium mineralization. The other anomalous uranium values were found to be related with the guano and phosphate deposits. Uranium was also shown to be independent of the other seven elements in the geologic environment of Cebu. No definite elemental association could be established at present. This study also marks the . thorough utilization of Q'GAS, Cadplot and Autocad, all microcomputer-based programs/systems, in the evaluation and interpretation of exploration-oriented geochemical and geological data, and with more significance in the sense that computer generated quality geochemical maps were produced, a first in the country. PNRI B(EA)89001 Page 2

1. INTRODUCTION 1.1 Purpose and Scope of the Report This technical report summarizes fifty (50) days of reconnaissance geochemical and radiometric surveys for uranium in Cebu Island (Fig. 1). The total area covered by the survey was about 5,080 sq. km. The survey was part of the evaluation of the uranium resource potential of the country. The diffferent exploration techniques that were used in the present survey included stream sediment and water sampling, heavy mineral pan concentrate sampling, and radiometric and geologic mapping. From the results of the survey, prospective areas for uranium and other metallic elements were delineated.

This report also aims to make full use of microcomputer-based programs/systems specifically the application of Q'GAS in the evaluation of exploration-oriented geochemical and geological data and more importantly, the application of Cadplot, an in-house developed computer program, combined with Autocad in the generation of color-coded geochemical symbol maps for better presentation and easier anomaly identification of prospective areas. 1.2 Location and Accessibility Cebu, one of the Visayan group of islands, situated in central Philippines lies between 9<>35'32" and 11© 17'17" latitude and extends from 123<>22'25" to 124°02'44" longitude. Cebu City, the capital is about 565 km. air distance from Manila. It is bounded in the west by Tanon Strait, in the east by Cebu Strait Fig. 1. LOCATION MAP OF CEBU PNRI B(EA)89001 Page 4 and in the north by the Visayan Sea. Accessibility to the Island is either by plane or by interisland vessel. The Philippine Airlines maintains several daily flights from Manila to Hactan Airport. William Lines, Inc., C. Go Thong Lines, Inc., Sulpicio Lines and Sweet Lines operate interisland vessels that call on Manila and Cebu City. The Island is circumscribed by all weather, hard surface roads that fringe the narrow coastal plain. Several mountain passes afford the main access between the east and west coasts, such as the Cebu-Toledo road and the Cebu-Barili road. Numerous short hard to loose surface roads and trails interconnect habitations in the interior. During the dry season, dried up large streams serve vehicular traffic.

1.3 Climate. Vegetation and Culture

More than thiee-fourths of the Island falls under the Type III Climate of PAGASA, i.e., with seasons not very pronounced; relatively dry from November to April and wet during the rest of the year. The less than one-fourth northern part falls under the Type IV Climate, that is, with rainfall mere or less evenly distributed throughout the year. Based on PAGASA s Monthly Rainfall and Cyclones in the Philippines Chart, maximum rainfall occurs in the months of July (230 mm) and September (210 mm) in Cebu City.

Generally, the whole Island is thinly vegetated, covered mainly by shrubs and low bushes. Small portions of rain forests and second growth trees are confined mainly in the interior and limestone areas. The alluvial flats and level areas are PNRI B(EA)89001 Page 5 cultivated to rice, corn and sugar cane. Cogon grass grows abundantly in most parts of mountainous areas. Settlement is characterized by both compact and dispersed types. The habitants are concentrated mostly along coastal and mining areas. In higher elevated forested areas, the communities are of the nucleated type. The main sources of living are agriculture, fishing, cottage industry and mining. Well-develcped commercial activities are present in Cebu City and some urban areas. 1.4 Previous Work The earliest recorded activity to look for uranium in Cebu was a preliminary survey by a joint team of the Bureau of Mines and the U.S. Atomic Energy Commission in 1953, covering the copper mines of Atlas Consolidated Mines in Toledo and the Danao Coal Mines. The results were negative. In November 1964, the late Dr. James Cameron, an International Atomic Energy Agency (IAEA) expert assigned with the Philippine Atomic Energy Commission (PAEC) now Philippine Nuclear Research Institute (PNRI), visited the Toledo Mine and its surrounding areas. His findings (see Cameron, 1965) are summarized as follow: The open pit gave negative results with the use of a Geiger Muller Counter. The concentrate and flotation tailings, after gravity concentration likewise gave negative results with the use of a beta scaler. The phosphate areas were also negative. The phosphate rock of the Atlas Fertilizer Plant when analyzed radiometrically by a beta scaler showed 0.004% eU30s content. PNRI B(EA)89001 Page 6

Despite these results, he recommended that the Island be further studied by aeroradiometric survey. He mentioned specifically the central part of the Island where mineral ore and phosphate deposits, basement complex and plutonic igneous rocks exist. No other work for uranium was conducted since then. Cebu, however, is widely prospected for metallic and non-metallic deposits. The biggest copper mine in the Far East is fsund in Cebu. Oil seepages are likewise reported (Bureau of Minee, .1.976). l. 5 Present Eleldjg^xk. The survey w*s a combined geological, geochemical and radiometric exploration for uranium. Prior to the fieldwork, the location of the sampling stations were pre-plotted in the 1:50,000 scale topographic maps published by the Bureau of Coast and Geodetic Survey. These same maps were used in the field. The survey was funded solely by PAEC in the amount of P66.222.60, excluding salaries of PAEC personnel and analytical costs. The members of the survey teams and the analytical staff include the following: Survey party 1. Elmer C. Hernandez - Field Party Supervisor 2. Wilfred N. Magsambol - Asst. Field Party Supervisor, Team Leader and SDO 3. Francisco V. Marcelo - Field Laboratory In-charge 4. Rolando Y. Reyes - Team Leader 5. Angelito F. Ramos - Team Leader 6. Nestor J. Bugaoisan - Asst. to the Field Laboratory In-charge, Draftsman PNRI B(EA)89001 Page 7

7. Rodrigo A. Tabios - Driver-mechanic Analytical Staff 1. Delcy T. Villamater - In-charge, Fluorimetry 2. Julietta Seguis - In-charge, AAS 3. Rosalina Almoneda 4. Hiltrudes Ortile 5. Jose Tagayun

2. GEOLOGY AND MINERAL RESOURCES OF CEBU The geology and mineral resources of Cebu Island are discussed briefly to relate their significance to the geochemical anomalies and uranium possibilities. The bulk of the materials presented in this part of the report was taken from the compiled 1:50,000 Geology Quadrangle Maps of Cebu (1983) published by the Bureau of Mines and Geosciences. The works of Corby (1951) and S.B. Jac;olinn (1960) were also used in the discussion. Figure 2 shows the geology of Cebu Island. 2.1 Geomorphology

Cebu is a long, narrow and mountainous island with its major axis trending north-northeast. In general, it exhibits a youthful stage of topographic development characterized by deeply dissected valleys, high interstream divides especially in the interior and upstream courses, and steep to gently rolling terrain of comparatively moderate to high relief. The highest elevation is about 1000 m situated in central Cordillera, this area characterized dominantly by igneous and metamorphic rocks, and - r.

S >:-t , | PI,.Li, 1 ' t' £ i .- "i rf f=J -; '• • ft. ^ Ld i?Hi:

*'- * 4 ID y *. t- ' ^ i -; f. *• i • ! . , Ld 3 • >: 1 * .-- ft-;- ._,r-- ._,rfv3 3^ ^ "* -* _J % ii rlMi ;s$ * \ to ls8 hi-:: *• ?'_•'.> •* j •: •* _ *• ,\ '• ;• a: •>••.. .. -' • ••' -" ,- - •: •;.*.-i :• • r\/ „ ' t— ••;V; 3"-s !'.<. VI * t r i * . *.:• 5- i* • • .:,:.- MV .-;*.' ,v.-:

'•';..;.'•'..;-'i„ ! •-I .' '•;V:.:-,;;J.V. *• • a j ;;

SECTION 1 Otf P.: .:„- c'.;r:..'-.-. i.yivn.i X" !-te

•C'. .•- .-'/ 5i->>.-:. ..r >...•.*>:. c'. " :..*..•«.: „•..,, -,», j..', ,,i ..j,.

MACTAN ISLAND ••4.'*.-:*. i-^..v .->.*;/;..••,*, U. !* 'i-'. --i Taltoy

ij*j

Crf" %

« JA /

MitHMrtt CO rn en

PHILIPPINE NUCLEAR RESEARCH INSTITUTE Qtfj

K> URANIUM EXPLDRATIDN PRDJECT

)ttr CEBU ISLAND «M> Fig, 2 GEDLDGY QF CEBU

-2r PNFI B(EA)89001 Page 9 partly mantled by highly faulted and folded Tertiary sedimentary rocks. The narrow coastal plain fringing the island is generally elevated coral platform with thin veneer of alluvial fans. Terracing is prominently developed especially in the northeastern side of the island. Another striking feature of the island is the presence of almost symmetrical conical hills, although imperfectly developed within the Carcar limestone. The islands's drainage pattern generally conforms with its topographic divide.

2.2 Lithology The oldest rock unit in the island is the pre-Cretaceous Tunlob Schist. It consists mainly of chloritic orthoschist and micaceous paraschist of the albite-epidote-amphibolite facies. Typical exposures are found in the northern part of the Cebu central Cordillera. They occur as irregular bodies and usually in fault contact with the Mananga group.

lha Mananga group, well exposed in the central Cordillera, lies unconformably over the Tunlob schist and mostly in fault contact with the surrounding rock units. As a whole, it is made up of a sequence of early Cretaceous limestone, clastic sedimentary rocks, andesitic to basaltic pyroclastics and lava, and Paleocene conglomerate, sandstone and calcareous mudstone. This group includes the regionally metamorphosed Pandan formation, the Cansi volcanics which is made up nostly of basic lava flows and the Tuburan limestone which occurs as small isolated ridge top PNRI B(EA)89001 Page 10 remnants that form very conspicuous peaks. Intruded into the Hananga group are plutonic masses of Lutopan diorite. The bulk of these intrusives are essentially hornblende-biotite diorite and quartz diorite. Generally, the diorites are light colored, medium to coarse grained and equigranular. Resting uncomformably over the Cretaceous rock units are small isolated bodies of Eocene massive limestone known as the Baye formation. Nummulites are abundant. Widely exposed in the central highland are conformable sequence of highly faulted and folded Oligocene to early Miocene sedimentary rocks referred to as the Naga-Argao group. This group is subdivided into the Lutak Hill formation, the Cebu formation and the Malubog formation. The Lutak Hill formation, which contains lepidocyclima and nummulites, is made up of limestone with basal sandstone. The Cebu formation, on the other hand, is composed of basal conglomerate, clastic sediments with intercalated coal deposits and upper massive orbitoidal limestone. This limestone is widespread. It is white in appearance, hard and impervious. Within the Toledo district, the limestone crops out as a narrow belt forming very conspicuous ridges. An equivalent occurence of this formation is the Butong limestone found in the southern part of the island.

Conformable over the Cebu formation, occuring continuously from Naga to Danao in the eastern side of the island and apart in the Toledo district, is the Malubog formation. Locally, the PNHI B(EA)89001 Page 11

Malubog formation is comprised of shale, mudstone and occasional beds of conglomerate, sandstone, limestone, carbonaceous shale and coal. This unit includes the Alpaco member, the middle Binabac limes cone member and the Cantabaco mudstone member. Counterparts of the Malubog formation are the Linut-od formation and the Hantalongo.i limestone that occur in the Argao-Dalaguete district. The middle Miocene rock units composed of intrusive bodies and sedimentary elastics belong to the Balamban group. The intruci\es are represented by the Talamban diorite, serpentinized peridotite and mafic rocks and the Bulacao andesite. The Talamban diorite which crops out as small discordant body is well defined near Consolacion area. The mass of this intrusive is mainly hornblende diorite with magnetite-bearing skarn along contact zones. In place, it is light colored and medium to fine grained in texture. Thrusted against older schist formation and Cretaceous rocks are diapiric bodies of serpentinized peridotite and mafic rocks. The Bulacao andesite, which occurs as irregular bodies is well exemplified in the eastern side of the central highland. In the type locality in Naga, the Bulacao andesite appears to be a partially intrusive breccia; in the Consolacion area, it is partly extrusive with porphyritic portions. The rock, in general, is essentially andesitic, and porphyritic as well where feldspar laths constitute the phenocrysts.

The sedimentary member of this group is widely distributed in the central highland, an area that is characterized by highly faulted clastic rocks. The member is subdivided into the Luka PNRI B(EA)89001 Page 12 formation, the Uling limestone and the Toledo formation. The Luka formation composed of interbedded sandstone and mudstone with conglomerate and limestone lenses constitutes a small portion of the group. The Uling limestone, which is generally a transgressive limestone, exhibits white appearance. It is massive, relatively hard and coralline. It is also fossiliferous with some orbitoids. Hide exposures crop out in the Mt. Dling, Toledo, Catmon and Liloan districts, where in some places they lie directly on basement rocks. Conformable over the Uling limestone is the Toledo formation. This formation consists of a sequence of thin to thick bedded white shale, sandstone with occasional lenses of conglomeritic limestone, and calcarenite that is characterized by abundant forams and scarcely by megafossils.

Resting uncomformably over the Toledo formation is the late Miocene Maingit formation, exposed as discontinuous bodies on the west side from Balamban southward to Pinamungahan and in the eastern side along Naga, Compostela and Carmen areas. Lithologically, the Maingit formation is differentiated into basal limestone, middle conglomerate and upper sandstone and shale. The basal limestone contains numerous corals and few microfossils. Bedding is quite distinct. The middle conglomerate, on the other hand, is composed of loosely consolidated and poorly sorted granule to cobble sandstone, conglomerate and pebbles of partially older rocks, while the upper member is made up of interbedded sandstone and shale, stringers of coal deposits and occasional thin beds of limestone. PNBI B(EA)89001 Page 13

Lying uncomformably against the Carcar formation is the highly folded Pliocene Barili formation. Stratigraphically, the Barili formation is divided into the lower limestone member and the upper marl member with sandstone 'interbed and basal conglomerate. The limestone member is the most widespread and it constitutes a major portion of the formation. It is a transgressive limestone that lies directly upon every older formation in some places. Typically, it is light brown, massive, coralline and porous. The upper marl member, which contains abundant fossils mostly of forams exhibits brown color. It is poorly bedded and slightly sandy with occasional thin stringers of limestone.

The Carcar formation constitutes the youngest and most widespread Tertiary sedimentary rocks in Cebu. It lies uncomformably over the Barili formation and covers entirely the coastal areas of the island. Locally, the Carcar formation is composed of limestone, limy tuff, marl with minor interbeds of limestone, conglomerate and sandstone. The limestone is the most common. It is porous, coralline, poorly bedded and massive. It is also partly dolomitic. Micro- and mega-fossils of mostly corals and other marine fauna are abundant. Haycock topography is a characteristic feature, although imperfectly developed.

Recent alluvial deposits are mainly accumulated clay, silt, sand and gravel. 2.3 Structures Cebu Island exhibits a long, narrow mountainous ridge with PNRI B(EA)89001 Page 14 its major axis trending north-northeast. The central Cordillera, a donal structure, formed by the uplift of the central core presents a highly complex structural feature characterized by several major northeast trending fault and fold structures. Within the central highland, are exposed strata of strongly faulted and folded Cretaceous-Paleocene mexamorphic and igneous rocks. These older rocks are flanked by moderate to gently folded Tertiary sedimentary rocks and extrusives. Thrust faulting is also well defined and in most cases serves as the lithologic contacts between the ultramafic complex and the older formations in the central highland. In the Argao-Dalaguete district toward the southern part of the island, two major structural units were disclosed - the northward trending fault and the west trending fault. The former traceable for a distance, defines the Pandan series from the Cebu formation, while the latter cut across the Naga-Argao group. In general, the rocks embraced by these faults are severely deformed as evidenced by intense shearing and fracturing. Folds are likewise developed as manifested by strongly folded strata of Oligocene to early Miocene sedimentary rocks. Fold axes generally trend north and northwest.

Toward the northern part of the island, foldings are well illustrated, particularly in areas underlain by Pliocene Barili formation and Pleistocene Carcar limestone. The general direction of their axes roughly parallels the island's main ridge. PNRI B(BA)89001 Page 15

2.4 Mineral deposits Mineral prospects in the island have uncovered many significant deposits, both metallic and non-metallic, that are of economic significance. The metallic minerals include copper, gold, lead and zinc. Atlas Consolidated Development and Mining Corporation in Toledo operates a copper mine. The deposit is a phorphyry copper type. Other deposits include gold deposition within the highly chloriti2ed and sericitized andesite as fracture fillings and disseminated grains. Gold panning was also reported in Buanoy area particularly upstream of Atlas mine. Lead and zinc, noted in the diorite and andesite rocks were mentioned in the Liloan area.

The non-metallic minerals include coal, dolomitic limestone and guano. The coal deposits, widely exposed in the island occur in Toledo, Mt. Uling, Danao, Ablayan, Mantalongon, Argao and Dalaguete areas. It usually occurs as lenses interbedded with thick sequences of conglomerate, sandstone, shale and limestone. In several localities, from 3 to 5 coal beds more than 35 cm thick were found. At present, coal is being mined commercially and in some places are extracted using camote mining. Dolomitic limestone occurs as irregular masses in the Carcar formation. Guano deposits, on the other hand are found in caves.

The Island was also extensively explored for oil and natural gas. The target area was the Alegria anticline. This anticline is characterized by Miocene Maingit elastics. Several shallow and PNRI B(EA)89001 Page 16 deep wells were drilled In the area. Oil was indicated.

3. PROCEDURES 3.1 Field Procedures The surveyed area covers about 5,088 sq. km. The sampling density was in the order of 1 sample per 15 to 30 sq. km. One set of samples comprised of one stream sediment, one heavy mineral pan concentrate and two stream water samples. Scintillometer reading, conductivity and pH measurements were taken at each sampling point. Reconnaissance geologic mapping was also carried out while sampling was going on. The heavy mineral concentrates were obtained using wooden pans. The survey team headed by a professional was composed of four to five persons. In all, 365 stations were visited.

At the field camp, the radon gas content of stream water samples was measured with the use of a portable radon monitor (EDA RD-200) and a water degassing unit (EDA RDU-200). The stream sediment samples were sun dried and sifted through the 80 mesh screen. The heavy mineral samples were prepared using bromoform (sp. gr. = 2.85). The magnetic minerals were separated from the non-magnetic portion by using a hand magnet. The non-magnetic fraction was collected for analysis. 3.2 Analytical Methods At the PNRI laboratory, the prepared stream sediment and heavy mineral samples were analyzed for U, Cu, Pb, Zn, Mn, Ag, Co and Ni. The stream water samples were analyzed for mobile uranium PNRI B(EA)89001 Page 17 by fluorinetry, according to the techniques described by Smith and Lynch (1969). The laboratory averaged about 70 samples per day on a routine basis. The detection limit for uranium was 0.2 ppb for water samples and 0.2 ppm for solid samples. The other seven elements were analyzed by atomic absorption spectroscopy (AAS). The detection limits were: 4 ppm for copper, lead, cobalt and nickel; 2 ppm for zinc and manganese; and, 0.4 ppm for silver. All in all, 4518 elemental determinations were carried out in 857 samples of different types. 3.3 Statistical Treatment of Field and Analytical Data In general, there are two approaches in evaluating geochemical data prior to interpretation. One is to take into account geological considerations before applying statistical analysis on the data, and the other is to do statistical analysis first and later correlate the resulting statistical parameters to geological environment. The latter was used inasmuch as there were only about 365 sampling stations that represent an average density of about 15 to 30 sq. km. per sample. Also, it was difficult to assign a sample to a certain geological unit or formation particularly in central Cebu where the geology is complex.

All analytical data were processed using the computer software Q'GAS (Lavin and Nichol, 1981) and were statistically treated using the univariate analytical method. The method is described as follows: First, total data were used to eetimate the statistical PNRI B(EA)89001 Page 18 parameters and the histogram was graphically displayed on the computer terminal in order to reveal the distribution of the data. Second, if the histogram did not show normality or near normality, logarithmic transformation of the data was performed, the statistical parameters were computed, and the histogram was displayed again. Third, if normality was not still achieved, the criterion of selection was used whereby extremely high values that may affect the normality of the distribution were removed. With the Cebu data, samples found contaminated with mine tailings were removed from the computations. The Chi-square test for normality was used to check the fitness at the 10% level of significance. Table I shows the summary statistics of the preliminary investigation using the above procedure while Appendices 1 to 5 show the histograms that exhibit the best structure of the distributions.

All distributions were found to be lognormal except for Pb in stream sediment and scintillometer readings. The arithmetic mean or the geometric mean depending on the distribution was taken to be the background value while the threshold value was conveniently estimated at the mean plus 1.5 the standard deviation since majority of the histograms show a break at this interval. Values greater than the threshold value were considered as anomalous. Table II shows the summary statistics showing the background and threshold values.

The Pearson linear correlation coefficient was applied between all element pairs in order to get information on the Pill Put 19

TI1LII

mm sririsrics ISIK TOTAL MM PIILIIIIA1T IlflSTIGATIOi 01 Til MTIII 01 DISTIIBDTIOIS

I i i Tne! iTraufof ! Selec !Prefer! I i i ! ! ! Coef of ' limn ! utioa ! tioi i red! 1 ! Bli ! lax ! leu ! Stdei ! Skew ! lart ! of 1 1 i snm ! 9 ! i 1 ! ! ! Tar

i . i 0 i i 365 ! 8.1 ! 1.3 ! 0.21 ! 0.19 ! 2.24! 6.30! 88.61 i . i ! loc i i 365 ! -1.0 ! O.li'. ! -0.789 ! 0.29 ! 1.02! -0.30! -36.73 ! loc !Cu>500 ! I ! 361 ! -1.0 ! 0.114 ! -0.787 ! 0.29 ! 1.00! -0.34! -36.93 • Co i i 365 ! 0.4 ! 17300.0 ! 100.99 ! 159.59 ! 16.341282.761 950.22 ! ! >500 ; 361 ! 0.4 ! 228.4 ! 28.5 ! 25.87 ! 2.64! 12.38! 90.76 i . i ! log i i 3S5 ! -0.398 ! 4.238 ! 1.31 ! 0.49 ! 0.53! 6.27! 37.42 ! log ! >5C0 ; I ! 361 ! -0.398 ! 2.359 ! 1.286 ! 0.43 ! -0.92! 1.78! 33.24 • Fb 1 1 365 ! 4.0 ! 72.0 ! 34.48 ! 9.88 ! 0.32! 0.86! 28.67 ! :Cn>500 ! I ! 361 ! 4.0 ! 68.0 ! 34.34 ! 9.63 i 0.18! 0.57! 28.04

• i . i Za i i 365 ! 6.4 ! 217.6 ! 49.15 ! 31.23 ! 1.97! 6.96! 63.54 i . i ! log i i 365 ! ,.806 ! 2.338 ! 1.612 ! 0.27 ! -0.21! -0.24! 16.70 ! log !CQ>500 ! I ! 361 ! 0.806 ! 2.338 ! 1.606 ! 0.26 ! -0.28! -0.33! 16.43

J i . i In • i 365 ', 8.0 !'i628. 0 ! 523.82 ! 554.20 ', 3.83! 24.28! 105.80 i . i ! log i i 365 ! 0.903 ! 3.75 ! 2.541 ! 0.41 ! -0.43! 0.62! 16.30 ! log ;Ci>500 J I ! 361 ! 0.(03 ! 3.75 ! 2.541 ! 0.42 ! -0.42! 0.60! 16.37

j 1 . 1 *I 1 1 365 ! 0.2 ! 3.6 ! 0.74 ! 0.72 ! 1.54! 1.79! 97.09 1 . 1 ! log • 1 365 ! -0.699 ! 0.556 ! -0.308 ! 0.39 ! 0.45! -1.191-125.91 ! log !Ca)t00 ; I ! 361 ! -0.699 ! 0.556 ! -0.307 ! 0.39 ! 0.44! -l.19M26.il

j 1 . 1 Co 1 f 365 ,' 4.0 :' 96.0 ! 21.63 ,' 11.62 ,' 2.14! 9.06! 53.73 1 . 1 ! log 1 1 365 ! G.602 ! 1.982 ! 1.282 ! 0.22 ! -0.13! 0.61! 16.94 ! log !Co>»0 ! I ! 361 ! 0.602 ! 1.833 ! 1.276 ! 0.21 ! -0.30! 0.38! 16.49

J i . i 11 i i 365 ! 4.0 ! 88.0 i 30.80 ! 16.36 ! 1.18! 0.96! 53.10 i . i i log i i 365 ', 0.602 ! 1.944 ! 1.431 ! 0.23 ! -0.24! 0.65! 15.91 ! log !Ca>500 ! I ! 361 ! 0.602 ! 1.944 ! 1.429 ! 0.23 ! -0.23! 0.66! 15.91

S 0 j 161 ! 0.2 ! 11.9 ! 1.18 ', 1.65 ! 4.26! 20.69! 139.31 i . i T» ! log i i I ! 161 ! -0.699 ! 1.076 ! -0.129 ! 0.40 ! 0.32! 0.161-308.42

IT la i . i 172 ! G.21 ! 200.05 ! 11.33 ! 23.47 ! 4.29! 25.19! 207.15 i . i !ii ! log i i I ! 172 ! -0.678 ! 2.301 ! 0.483 ! 0.71 i 0.26! -0.59! 147.53 II .' log I >100 J 171 I -0.678 I 1.991 ,' 0.472 ! 0.70 ! 0.22,' -0.66! 146.36 • - Tsloes that affect the dlatrlbotlon tere reeo?ed froi itatlttical calculation. I - With dran aistograu. Nil 8(11)89911 Fife 20

Till! I (Coit'd)

SmilT STATISTICS ISIK TOTAL DlTl PIILIIIM1T IIWSTIGHIOI

! Tjpe JTraasfor! Selec !Prefer! ! ! ! Coef ! of iLUini aatioa i tiom ! red ! 1 ! •in ! lax ! fleai ! Stde? ! Skei ! tort ! of ISI1TIT ! § ! ! ! ! Tar

B ! . 151 ! 0.1 ! 3.0 ! 0.32 ! 0.37 ! 3.56! 18.02! 113.97 lot i • i 159 ! -1.8 ! 0.4T7 ! -0.65 ! 0.35 ! 0.71! -0.31! -53.89 log :cu>5ooo: I i 154 ! -1.0 ! 0.477 ! -0.647 ! 0.35 ! 0.70! -0.27! -53.86

Cu ! . i i 158 ! 0.4 ! 10000.0 ! 295.05 ! 1308.44 ! 6.23! 38.90! 443.47 - ! >500 ! 150 ! 0.4 ! 343.6 ! 68.49 i 70.52 ! 1.64! 2.30! 102.96 log 158 ! -0.398 ! 4.0 ! 1.682 ! 0.67 ! 0.36! "-72! 39.82 log ! >5000! I ! 154 ! -0.398 i 3.261 ! 1.624 ! 0.57 ! -0.62! 1-76! 35.28

n ! . 158 ! 4.0 11808.0 ! 129.57 ! 271.69 ! 3.97! 17.11! 209.19 log 158 ! 0.602 i 3.257 ! 1.689 ! 0.56 ! 0.56! 0.22! 32.97 lof !Co>5000! I ! 154 ! 0.602 ! 3.257 ! 1.682 ! 0.56 ! 0.60! 6-20! 33.43

ZB ! . 158 ! 5.6 11548.0 ! 88.79 ! 166.83 ! 5.88! 42.10! 187.90 log 158 ! 0.748 ! 3.19 ! 1.645 ! 0.49 ! 0.28! -0.23! 29.88 - i >780 ! 155 ! 5.6 ! 376.0 ! 68.88 ! 73.66 ! 2.16! 5.29! 106.94 log ! >T80 ! 155 ! 0.748 ! 2.575 ! 1.618 ! 0.46 ! -0.03! -0-95! 28.17 log !Cu>5000| I ! 154 ! 0.748 ! 3.190 ! 1.632 ! 0.49 ! 0.31! -0.16! 29.93

In ! . i i 158 ! 56.0 ! 21360.0 ! 1096.15 ! 3232.06 ! 4.97! 24.90! 294.86 log 158 ! 1.748 ! 4.330 ! 2.549 ! 0.50 ! 1.59! 2.80! 19.48 log ! >10000! 153 i 1.748 ! 3.833 ! 2.494 ! 0.40 ! 1.06! 1.09! 15.66 log !Cn>5000! I ! 154 ! 1.746 ! 4.330 ! 2.561 ! 0.50 ! 1.60! 2.77! 19.36

il ! . i . i 158 ! 0.2 ! 7.6 ! 0.90 ! 1.00 ! 2.89! 12.91! 110.68 log 158 ! -0.699 ! 0.881 ! -0.244 ! 0.41 ! 0.36! -l.03i-168.00 log !Co>5000! I ! 154 ! -0.699 ! 0.881 ! -0.258 ! 0.41 ! 0.42! -0.92!-157.09

1 _ 1 Co ! . 1 1 158 ! 4.0 ! 168.0 ! 30.30 ! 26.03 ! 2.32! 7.60! 85.90 1 . 1 log 1 1 158 ! 0.602 ! 2.225 ! 1.348 ! 0.35 ! -0.13! -9.28! 25.85 log iCo>5000! I ! 154 ! 0.602 ! 2.064 i 1.330 ! 0.33 ! -0.30! -0.45! 24.97

11 ! . 158 ! 4.0 ! 136.0 ! 30.78 ! 26.25 ! 1.41! 1.79! 85.26 log ! - ' 158 ! 0.602 ! 2.134 ! 1.325 ! 0.40 ! -0.27! -0.74! 30.33 lof !Co>S000i I ! 154 ! 0.602 ! 2.134 ! 1.313 ! 0.40 ! -0.25! -0.73! 30.36

ISCIITILLOHTIB! . 1 - 1 1 1 352 ! 10.0 ! 57.0 ! 21.42 i 5.62 ! 1.35! 4.53! 26.21 - ! >45 ! Z ! 351 ! 10.0 ! 43.0 ! 21.32 ! 5.29 ! 0.81! 0.82! 24.82

I - Values tkat affect the distribution «ere reaoved froi itatiitical calculation. I • With dram hiitogran. PNRI B(EA)89001 Page 21

TABLE II SUMMARY STATISTICS SHOWING THE BACKGROUND AND THRESHOLD VALUES

TYPI5 OF ! TYPE OF ! {STANDARD !BACKGROUND!THRESHOLD SURVEY ELEMENT[DISTRIBUTION! MEAN !DEVIATION! VALUE * ! VALUE # Stream U J log ! -0.111 ! 0.38 ! 0.77 ppb ,' 2.90 ppb Water Rn ! log ! 0.483 ! 0.71 ! 3.04 cpm [35.56 cpm S U ! log ! -0.787 ! 0.29 ! 0.16 ! 0.52 S E Cu ! log ! 1.286 ! 0.43 ! 19.32 ! 84.72 + + + + + T D Pb ! natural ', 34.340 ! 9.63 ! 34.34 ', 48.78 R I Zn ! log ! 1.606 ! 0.26 ! 40.36 ! 100.46 E M Mn ! log ! 2.541 ! 0.42 ,' 347.46 ! 1462.18 A E Ag ! log ! -0.307 ! 0.39 ! 0.49 ! 2.07 M N Co ! lo'g ,' 1.276 ! 0.21 ! 18.88 ! 38.99 T Ni ! log ! 1.429 ! 0.23 ! 26.85 ! 58.82 M U ! log ! -0.647 ! 0.35 ! 0.23 { 0.80 + + + + + H I Cu ! log ! 1.624 ! 0.57 ! 42.07 ! 304.44 E N Pb ! log ! 1.682 ! 0.56 ! 48.08 ! 334.96 A E Zn ! log ! 1.632 ! 0.49 I 42.85 ! 231.21 + + + + + V R Mn ! log ! 2.561 ! 0.50 ! 363.91 !2018.37 Y A Ag ! log ! -0.258 ! 0.41 ! 0.55 ! 2.49 L Co ! log ! 1.330 ! 0.33 i 21.38 I 67.30 S Ni ! log ! 1.313 ! 0.40 ! 20.55 ! 81.28 Scintil.Lomete r ! natural !21.32cps! 5.29 ! 21.32 cps!29.25 cps * - Standardized to SPP-2NF - Scintillometer readings in cps # - All values in ppro unless specified at specific element, cpm - counts per minute; cps - counts per second ppb - parts per billion; ppm - parts per million PNRI B(EA)89001 Page 22 structure of inter-element relationships. The correlation matrices of elements in stream sediments and heavy minerals are shown in Tables III and IV respectively. Appendices 6 to 23 show the scatter plots where statistically significant correlations were observed. 3.4 Map Presentations In order to better present geochemical exploration information, a computerized color coded symbol map was adopted. This is a convenient graphic representation of element values where the values themselves are color coded into classes or a range of values. The selected element classes were based on the mean and standard deviation, and the degree of intensity of the color used corresponds to the level of significance of the range of values selected, i.e., brightest color (violet) represents the highest range of values while the least bright color (yellow) represents the lowest range of values. This has the advantage of easier anomaly idenstification. A computer program Cadplot was developed in-house and is interfaced with Autocad, a drafting package and product of Autodesk Inc. Cadplot produces a "drawing interchange file" for the color-coded elemental values and this file is processed by Autocad for the final generation of the geochemical maps.

4. RESULTS AND DISCUSSIONS 4.1 Scintillometer Survey A total of 352 scintillometer readings were taken and were PNRI B(EA)89001 Page 23

TABLE III CORRELATION COEFFICIENT MATRIX OF ELEMENTS IN STREAM SEDIMENTS BASED ON 361 SAMPLES

ELEMENT! Cu { Pb { Zn ! Mn ! Ag ! Co } Ni + + + + + + + D i -0.162 ! 0.140 ! -0.227 ! -0.323 ! 0.271 ! -0.261 ! -0.173

+ + + + + + + Cu ! ! 0.009 ; 0.622 ! 0.548 \ -0.013 J 0.447 ! 0.457 + + + + + + + Pb ! ! ! 0.100 ! -0.001 ! 0.293 ! 0.224 ! 0.228

+ + + + + + + Zn ! ! J ! 0.621 ! -0. 17 ! 0.527 } 0.564 + + + + + + + Mn ! ! ! ! ! -0.395 ! 0.609 ! 0.588 + + + + + + + Ag ! ! ! ! ! J -0.249 ! -0.123 + + + + + + + Co ! ! • ! ! ! ! ! 0.703

TABLE IV CORRELATION COEFFICIENT MATRIX OF ELEMENTS IN HEAVY MINERALS BASED ON 154 SAMPLES

ELEMENT! Cu ! Pb j Zn I Mn ! Ag ! Co ! Ni

+ + + + + + + U ! 0.035 ! 0.051 ! -0.042 ! -0.181 ! -0.172 ! -0.030 ! 0.049 + + + + + + + Cu ! ! 0.547 ! 0.584 ! 0.095 ! 0.434 ! 0.538 ! 0.418 + + + + + + + Pb J ! ! 0.647 ! 0.286 ! 0.452 ! 0.470 I 0.449 Zn ', ! ! ! 0.444 ! 0.642 i 0.729 ! 0.642 + + + + + + + Mn ! ! ! ! ! 0.396 ! 0.573 \ 0.387 + + + + + + + Ag ! ! ! ! ! ! 0.643 ! 0.585

+ + + + + + + Co ! ! ! ! ! ! ! 0.815 PNRI B(EA)89001 Page 24 standardized to the SPP-2NF scintillometer equivalent. Generally, the radiometric reading in Cebu were lower compared to previous surveys conducted in other parts of the country. The maximum reading observed was 57 counts per second (cps). Figure 3 shows the distribution of radiometric values. The background value is 21.33 cps while the anomalous values are those greater than 29.25 cps. An extensive area with anomalous values is delineated north of Mandawe City over the Carcar, Mananga, Talamban and Halubog formations. Five of these anomalous values were found to occur along the stretches of the Handawe River. The area drained by this river is characterized by Cretaceous limestone and clastic sedimentary rocks at the upper portion, by early Miocene mudstone, shale and conglomerate intruded by the middle Miocene Talamban diorite and Bulacao andesite at the middle portion, and Pleistocene poorly bedded to massive coralline limestone at the lower portion. The higher than normal readings may possibly be due to the presence of these intermediate rocks. Two other areas of possible interest occur south of Toledo City and at Alcoy near Dalaguete and these are underlain by coralline limestone of the Carcar formation.

4.2 Stream Water Survey

The total number of water samples collected was 333. Out of these, 151 stream water, 5 spring and 5 well samples were analyzed for uranium while 153 stream water, 6 spring and 13 well samples were analyzed for radon. Hater samples taken from holes dug on the stream beds of dry rivers were classified as well samples. 25 LEGEND BA/WGIANTAYAN SYMBOL pJJjJrj N HISTOGRAM

9 16.03 O 21.32

o 26.61 AHAPA&> 2925 }*• u o 31.90 N 19 CO 30 XFKOUENCV Cut point values m counts \ per second N - nunber of sanples

• %\ IANAO CITY

t» . LILOAN •nxtaa cm

CEBU

MACTAN ISLANI

• O

DUNWJUG

9 * 1SMONGA 6.7 0 &7 04lm

• 4 1 1 1 1

jS* HON}

* • (1 J BALAGUCTr.

MS.OHAI JWALCUY

- PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PROJECT CEBU ISLAND 'SANTAWtR FlQ. 3 SCINTILLOMETER READINGS PNRI B(EA)89001 Page 26

The stream water samples collected for uranium and radon analysis represent less than half of the sampling stations visited. This was due to the fact that many of the rivers were dry during the time of sampling. Distribution plots of uranium and radon are presented in Figures 4 and 5 respectively. 4.2.1 Uranium The over-all uranium content in stream water of Cebu is moderately high compared to other explored areas in the country. This is exhibited by the background value of 0.77 ppb which is more than twice the background value (0.3 ppb) in the Paracale district where known uranium mineralization occurs (Tauchid, 1978). Values higher than 2.90 ppb representing the anomalous values are very significant. A big area delineated by seven samples with values ranging from 4.3 ppb to 10.4 ppb are found north of Danao City. Part of the area that is being drained by these samples is the late Miocene Maingit formation composed of conglomerate that contains clasts of volcanic rocks, sandstone and shale which could be a possible provenance of uranium. The highest value (11.9 ppb) is found in the northern most tip of the island. This could not be due to sea water contamination since the measured conductivity reading is low. This site is also anomalous in the scintillometer survey.

4.2.2 Radon The background value for radon in Cebu stream water is 3.04 counts per minute (cpm) and values greater than 35.56 cpm are considered significant. Except for a large area near Tabuelan ar LEGEND SAMCMNTAYAN SYMBOL J3£L N HISTOGRAM POINTS 34 038 32 0.77 L87 76 Mvem\ 2.90 11 4.50 2 6 f] • • • N xracauDCY Cut point values in parts per billion I N - nunber of sanples • •

CATMM

ASTURIAS |

CEBU„ CITJ MACTAN ISLAND

•I MGA

SARIUl

# • M4ANJU6/

/LCANTMAX 6.7 0 6.7 l&4km. < •! I I 1 J

' HALAflvJtTE

KALAJV • •/

6WATM PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PROJECT CEBU ISLAND '

SYMML N HISTOGRAM P§NTS

KGQ

N >e ax xranuocr

Cut pant values m counts BORKM per nmute I N - nunber of samples

ASTURIAI |

BANAO CITY

TOLEDO CITY • •

CE1U„ CITY, HACTAN ISLANS

• a

1 CARCAR

I S1HNGA 6.7 0 6.7 13.4 1113

PAUWUETE

AUGftlAi I ALCtiY

SlMTiAl ' DSLDJ PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLDRATIDN PROJECT CEBU ISLAND 'WffAWW Fig. 5 RADON IN STREAM WATER PNRI B(EA)89001 Page 29 where a cluster of four anomalous values surrounded by several values higher than the background value are found, other anomalous values appear to be randomly distributed, and hence considered as point anomalies. Careful examination of the anomalous values showed that most of the randomly distributed anomalous values including the values delineating the area near Tabuelan are found along the Pleistocene Carcar formation. It may be noted that this formation is the most widespread in the island. This suggests that the variation in radon values is due to lithology, and the higher values found in the Carcar formation is just a reflection of the normal radon values in that type of environment.

The insignificant correlation coefficients show that there is no relationship between uranium and radon in stream water. The same is true between uranium and conductivity readings in stream water. 4.3 Uranium In Stream Sediments A total of 365 stream sediment samples were collected. The distribution of uranium values in the stream sediments is shown in Figure 6.

The uranium content o* stream sediments of Cebu is quite low. About 60% or a total of 218 stream sediment samples have values below the detection limit (0.2 ppm) of the analytical method used. The highest value obtained is only 1.3 ppm. The background value is 0.16 ppm and the. threshold value is 0.52 ppm. Several anomalous areas were outlined, the most notable is the large area between Aloguinsan and Pinamungahan, southwest of Toledo City. BAAWiJANTAYAN I V LEGEND

SYMML N HISTOGRAM POINTS 016 218 035 61 052 56 077 N 8

XFKSUOCY Cut point values m parts \ per NlUon N - nunber of sanples

•Hn.':mN I1:..AWL

6,7 0 6.7 l&4kn* 11 13

PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PROJECT CEBU ISLAND Fig. 6 URANIUM IN STREAM SEDIMENT PNRI B(EA)89001 Page 31

This area has four 0.6 ppm values surrounded by several 0.4 ppm values. This anomaly is within the small scale guano and phosphate type deposit outlined by JICA (1987). The relatively high content of uranium may be due to the traces of uranium generally found in guano and phosphate (Boyle, 1982). Another area is found near Carcar with three samples having value6 between 0.6 to 0.8 ppm. This could be an extension of the Aloguinsan-Pinamungahan area since it is directly situated some kilometers southeast of the area. Other areas delineated are the Alcoy-Dalaguete area with four anomalous values ranging from 0.6 to 1.2 ppm, Alegria-Malabuyoc area having three anomalous values of 0.6 ppm, Boljoon area with two values of 0.6 and 0.8 ppm, and Asturias area where the highest value of 1.3 ppm is found surrounded by two values of 0.4 and 0.6 ppm. The Aloguinsan-Pinamungahan and Alcoy-Dalaguete areas conforms with the anomalous areas delineated by the scintillometer survey. All the delineated anomalous areas are characterized by the Carcar formation. 4.4 Uranium In Heavy Minerals

Figure 7 shows the uranium distribution in the heavy minerals. The total number of samples collected was 159 and this represents about 44% of the total sampling stations visited. These values will be used to complement the significant findings of the other surveys except for obvious clustering of anomalous values. The respective background and threshold values are 0.23 and 0.8 ppm. About 39% or a total of 62 samples gave values below 3> LEGEND 3AANGIANTAYAN SYMBOL CUT N HISTOGRAM PDINTS Oil 62 o 023 39 •J KJQU o 052 31 o 0.80 18 o L22 5 ft • 4 | TABCCjON N » CO 30 IXFREOUENC Y o / 7 8DR8DN Cut point values m parts TMVtLMf 9 per Million T N - number f 0 <# snara of samples Jo 3 CATMDN

• • / • ••1

A.ITliRtAJ r I O . 8 1 DANAQ CITY e y* e * r • oe t LIL0AN TQl-ESn CIT- J • •• Z av£f J Of T^\ Jf 1ACTAN i"LANB

O o

6.7 0 6.7 13.4 km. I I I I

PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PROJECT CEBU ISLAND

Fig. 7 URANIUM IN HEAVY MINERALS PNRI B(EA>89001 Page 33 the detection limit of 0.2 ppm. The highest value of 3.0 ppm occurs in the upper portion of the left tributary of Mandawe River. Another anomalous value of 1.6 ppm occurs in the lower portion of the right tributary of the same river. These two values strengthen the area delineated by the scintillometer survey at the Mandawe River area. Of note is the single anomaly in stream sediment with a value of 0.6 ppm found in the same spot where the highest value in heavy minerals occurs. The catchment area drained by this sample is characterized by the Bulacao andesite and Talamban diorite. Magnetite-bearing skarn exists along the contact zones between the diorite and the Mananga formation. This could be a possible area for uranium mineralization. This geological setting is somewhat similar to the Larap, Camarines Norte uranium mineralization. The northernmost sample near Daangbantayan with a value of 1.7 ppm was earlier shown to be anomalous in stream water and scintillometer surveys. Two other point anomalies are found in the Aloguinsan-Pinamungahan area. This area is also anomalous in stream sediment, scintillometer and radon in stream water surveys. The area near Carcar is anomalous in the stream sediment survey. 4.5 Multi-Element Survey

All collected solid sanples were also analyzed for copper, lead, zinc, manganese, silver, cobalt and nickel. This is one advantage of geochemical exploration over other methods since an additional evaluation of the country's mineral potential can be obtained. Several areas of interest were delineated and these are PNBI B(EA)89001 Page 34 briefly described. 4.5.1 Copper The distribution of copper in stream sediment and heavy minerals is shown in Figures 8 and 9 respectively. The respective background and threshold values in stream sediments are 19.32 and 84.77 ppm. In the heavy minerals, the background and threshold values are 42.07 and 304.44 ppm respectively. The very high values of copper in both the stream sediment and heavy minerals samples taken along the Sapang Dako River are explained by the mining operations of Atlas Consolidated Mining and Development Company. The other high values found upstream of Sapang Dako River not affected by the Atlas mine tailings are due to intense gold panning around the area. The samples were most likely contaminated by the waste due to gold panning, thus concentrating and increasing the values of copper and other minerals present in the sediment.

An extensive area pinpointed by six stream sediment samples having a range of values from 86 - 117.2 ppm lies near Talisay and north of Naga. The high values of copper are presumably due to the intrusion of the Lutopan diorite into the Mananga formation. The presence of several northeast trending faults in the area could have been the avenues for deposition of the copper bearing solution in the form of fracture fillings, a type similar to the Atlas deposit.

Two anomalous values in heavy minerals having values of 304.8 and 1,908 ppm found near Carcar delineate an area characterized by LEGEND MANGtANTAYAN f -1 3? SYMBOL pQjjJ-j N HISTDGRAM

721 49 ican 5L76 > • £ ANAPA&X* 84.72 * J © .-.—. 11 1 /&8 eJ 138.68 " / J ° • 7 l • • • / o TTAKUUN " u a » \ A XFKOUOCY

Cut point values m ports J /iORBD N -11 per million J 1 / 0 N - number of samples saw

I CATHDN r x /•• * V * / • • f 'A ASTtjRIAS ("^ 1 • 1 •» I • * • |T EANAU CITY />o •* /> % • • Ac • * iff0* * •* • ( l.TLLIAN TH-Kun an J* % m • \ -r • • • •• yj cy*. 9f • . CEBU S^fl'^*(£f

>\« • • • .TiruT W X/ *1ACTAN ISLAM! yfJf «• • J^o«*> -^X TAU3A r / ^^ >0 - ?f NAGA A * / iftRiurP - <-• • li # » / X* • vJ asHHUUGji 0 J^a,R

AlCANTARAl 1 6,7 0 6.7 13.4 lot* r T ii ( o • °) ^V • of

d,f • +# S 3ARHA O

1 | / * i L * *( 1 •J n/\!.A:ii*:;f: r * if ALTfiPW* If if Jf ALOIY 1

KAI.AJil'lW £ y 1 • 7 / * 7 5INATil.Af* # -7 1 ^ni' u« PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PROJECT CEBU ISLAND M_J^SANTANI)f'.R Fig. 8 COPPER IN STREAM SEDIMENT ^ V LEGEND EaflNtJANTAVW SYMBOL CUT N HISTOGRAM PtFNTS 1125 18 n_ 4&07 61 54 157.40 15 ? 304.44 588.84 3 7 N £tt » 30 X FMBUENCY

Cut point values m parts per nlUlon I N - number of samples 9 »

• M ° 5.

«W:TAN ;,':i.ANT,

# o # e

6.7 0 &7 13.4 km. f °\ i— I I J

• •

0 »/

PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PRDJECT CEBU ISLAND

Fig. 9 COPPER IN HEAVY MINERALS PNBI B(EA)89001 Page 37 limestone of the Carcar formation. A skarn type deposit of copper is indicated. The anomalies found in this area support this theory. 4.5.2 Lead Figures 10 and 11 show the distribtuion of lead in stream sediments and heavy minerals respectively. Values over 48 ppm in stream sediments and/or values over 334 ppm in heavy minerals define areas of interests. The most striking feature of lead distribution is the clustering of four (56 - 60 ±>pm) and three (640 - 1,388 ppm) anomalous values in stream sediments and heavy minerals respectively around the area near Carcar. This was also found to be anomalous in copper in heavy minerals. This area is extended northwest to the other side of Cebu Island by the presence of three (52 - 56 ppm) anomalous values in stream sediments and one (344 ppm) anomalous value in heavy minerals. The large area is underlain by limestone of the Barili and Carcar formations.

Three samples located at the upper portion of the Sapang Dako River show anomalous values in stream sediments. As with copper, it is probable that the high values are caused by the gold panning in the area. The other anomalous values in both methods of survey are randomly distributed and are considered to be point anomalies. To be noted is the point anomaly in both surveys near Talisay. It is within the area outlined by anomalous values of copper in stream sediments. _r vt> LEGEND SYMBOL pQjjJre N HISTOGRAM r J

3*34 "? J ^> 9J31

' 4878 * : saw ,J P N X FKBUOCY f Cut point values m parts per NlUon t N - nunber of samples

6 o * •A A'TT^IAr f

. » • • gj DMAS CITY

' 8 • « 1fi.IL3A N 7D EIB CITY / ' „

I * • A1* > A

ALCANTARA! J 6.7 0 6,7 13.4 1m or; • «\ LI 1 1

t '* » 7

B J M.AIjilf.iK r * tf L M *•-'•!)v

FAI.AJilYtjr* £ ^ / • y SINATIIAW # .7 PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLDRATIDN PROJECT CEBU ISLAND La B^rAMTAUT,fL> v^^^^^^ inNi »?*.

48.08 El * 17539 » * 334.96 , r* * o Nii i i ii_ N » CO 30 xnsauocY Cut point values m parts ! per mUion

N - nunber of sanples 5CGUE

I r-ATMTIN

MATTAN iSLANB

6.7 0 6.7 13.4 km. f •! 1 1 1 J 0 • •

KAI.AlUYWf »

PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLDRATIDN PROJECT CEBU ISLAND

FIQ. 11 LEAD IN HEAVY MINERALS PNRI B(EA)89001 Page 40

4.5.3 Zinc Shown in Figures 12 and 13 are the respective distribution of zinc in stream sediments and heavy minerals. Zinc background values are 40.36 and 42.85 ppm in stream sediments and heavy minerals respectively. Anomalous zones are outlined by values greater than 100 ppm in stream sediments and/or values greater than 231 ppm in heavy minerals. Again, the samples along the Saoang Dako River affected by Atlas mine tailings showed high values of zinc.

A group of three anomalous values (108.4 - 162.8 ppm) in stream sediments surrounded by higher than background values was found in the upper tributaries of the Mandawe and Talisay Rivers. This area also shows the presence of one anomalous value (356 ppm) in heavy minerals together with three values higher than the background value. Underlying this area is the Bulacao andesite. Considering that the same area shows above normal geochemical values in Cu, Pb, Ag, Co and Ni implies a polymetallic hydrothermal deposition. Another area that could be considered as interesting is the Argao River area. A single anomaly in stream sediments (104.4 ppm) with two high values in heavy minerals (280 and 800 ppm) and several above background values occur along Argao River. The area is characterized by the Malubog, Cebu and Barili formations.

4.5.4 Manganese The manganese distribution in stream sediment and heavy minerals is shown in Figures 14 and 15 respectively. The SAANGBANTAYAN 1 41

LEGEND 0 / SYMBOL pgjj-j N HISTOGRAM

21-98 ,?? 4036 101 icm 3 ,\ . ™ 2 i ANAPA&\# ?# •J # 13644 ^ N f1 f t t

N - number of sanples '# • 30GBD Jo

1 CATNDN i rt e« / t ,• 1

p • o • • ASTURIAS f

• • • 8) DANAa CITY e • »• 0*» / e ° •• * ^V /* •* CEBU X ~/7 # •^ ^ 1* * • CITJrJ ) / / • 9 > >/ K • » HACTAN ISLAND EL> r y^'V / A" ' & Al.BAY A / i ^»^

# /* Jf • *«x * /{ DUNANJUGf • fr/WW

f * 1 StSDNtiA AlCANTARAl J H»um.« 6.7 0 6.7 1X4 kns. U • • o ] 1 • «l i 1 1 1 **\ • o/

/V> • *«? ^y AR0 'ID V> » % / / r° * *«i ^

rt . • V* ( DAI.AGUKTE

tuiaafig r v« / ^ ALCDY |« f HMAWmf ft / 1 * 7 I * /

1 y 0SLD8 PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLDRATIDN PROJECT CEBU ISLAND IH_ ^^^r fAUtAUK'O ^wa^^ »AN 1 ANUtK FIQ. 12 ZINC IN STREAM SEDIMENT LEGEND SMDOtMCKfftH I •/?- SYMBOL pCj^ N HISTOGRAM

° ens? ^-i BUB " , J 23ia I 8 N 11(130 xncauocY Cut point values to parts per mtUon I N - nunber of sanples

'.'ATMW

• *

e •

COD. Ci1 of MAfTAN i-TLANE

0 •

6.7 0 6.7 13141M. t •) T 1 I -J

• * •I 0^ AROAfl

DAI.«H*: rr

PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PROJECT CLBU ISLAND

Fig. 13 ZINC IN HEAVY MINERALS LEGEND UMNCKVCAYAN I M-3 SYMML pQjJys N HISTOGRAM 59 o 13335 111 o 347.46 154 905.73 o 21 146&18 16 2360.48 / N m M30 xnouDcr Cut potvt values m parts per niUion I N - nunber of sanples

• • • • • •)

t • 0*

MAT;AN .ruAW

,^# # ,y X * ° *£->

A/1 • » o\ 6.7 0 »7 VMtom. 1 • I (Ill

L * / >» V L • *( • JJ C«.AG*.:F

/ # AL'.'.tiY

I • 7 I * 7 iNATaxJf • #* y^ .1 J v.\m PHILIPPINE NUCLEAR RESEARCH INSTITUTE it f URANIUM EXPLORATION PROJECT CEBU ISLAND

FlQ. 14 MANGANESE IN STREAM SEDIMENT LEGEND JAANGKWTATAN I «N SYMBOL CUT N HISTOGRAM POINTS 11644 o o 363191 114085 201837 a 3572.73 N

Cut poftvt values m parts per MlUon I N - number of sanples :CGM IcATuns

e *

0 CO (p CEBU

MACTAN ISLAND

• •

6.7 0 6,7 WkM. f •> I 1 I J

• •

PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PROJECT CEBU ISLAND

Fig. 15 MANGANESE IN HEAVY MINERALS PNRI B(EA)89001 Page 45 respective background and threshold values in stream sediment are 347.46 and 1,462.18 ppm. In heavy minerals, the respective values are 363.91 and 2,018.37 ppm. The bulk of the anomalous values in stream sediments occur in a very large area in the northern part of Cebu Island between Anapag and Tabogon. Twelve samples having a range of values of 1,536 - 3,892 ppm were located in this area. The area is characterized by the porous limestone of the Barili and Carcar formations and the manganese anomaly could possibly occur as fillings and accumulations in the limestone cavities as bog type deposits.

In the heavy minerals, four areas were delineated and the most prominent is the Tapon Fiver (otherwise known as Dalaguete River in some literatures) area where four samples show very high values (14,040 - 21,360 ppm). The mineralization here is probably associated with the limy tuff member of the Carcar and Barili formations. Further north is the Argao River area where three samples gave a range of values of 2,092 - 4,516 ppm. High manganese values in this area could be attributed to the presence of the metamorphosed volcanic-derived conglomerates (Park and MacDiarmid, 1964) of the Cretaceous Pandan formation, exposed for about 4.5 kms. along Argao River (Barnes, H., et al, 1955). The two other areas occur in Alegria with three anomalous values of 15,120, 6,084 and 2,032 ppm and the other in Barili with two anomalous values of 4,616 and 2,592 ppm. The manganese in the Alegria area could be derived from the clastic sediments of PNRI B(EA)89001 Page 46 volcanic origin of the late Miocene Maingit formation while that of the Barili area may be due to accumulations in sinkholes. 4.5.5 Silver Easily noticeable about the distribution of silver in both the stream sediment (Fig. 16) and heavy minerals (Fig. 17) is the concentration of the lower values, particularly those below the detection limit (0.4 ppm) in central Cebu where the geology was earlier mentioned as complex. Except for the Mandawe-Talisay area where one anomalous value (>2.49 ppm) and three above background values (>0.56 ppm) in heavy minerals are found, silver values are very low in this area. Almost all of the anomalous values (>2.07 ppm) and several above background values (>0.49 ppm) in stream sediments are distributed over a wide area along the coast from Pinamungahan to Alcantara and from Badian point to Malabuyoc. Both extensive areas are characterized by the Carcar and Barili formations and partly by the Maingit formation in Alegria. In the heavy minerals, a clustering of three anomalous values were located in Guinatilan. This area is also underlain by the Carcar and Barili formations.

4.5.6 Cobalt The distribution of cobalt in Cebu Island is lower compared to the Average cobalt contents of similar rock«s in general. The range of values of cobalt in stream sediments (Fig. 18) is 4 - 96 ppm and for the heavy minerals, (Fig. 19) it is 4 - 168 ppm. The respective background and anomalous values for stream sediments are 18.88 and 38.99 ppm, and for heavy minerals, they are 21.38 BAANGJANTAYAN [ e •/ */>- LEGEND o 1 SYMBOL pgjj^ N HISTOGRAM

earn

ANAPAGV» 2-07 »

JTAKJGON N £to a » X FREQUENCY f •Y JDRJDN Cut point values in parts TAJUELAlJ^ per million / • + N - nunber of sanples • J tATMON • •

ASTURWS f^

o • C EANAD nlTY 0 »

/ 9 e

l.ILDAN Taron CITY I o J

/ MACTAN ISLAND

A* . of two*

jARRrl* - 7 if (

I * •»/ (\r • # «\ 6.7 0 &7 lMkra. L....1. 1 1 l • * °T

I Of

#/ • Jif ALcnr 1 •/ n«.A»uYtrf £ jw

i • . v ;,:NATU*« # _7 PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLDRATIDN PROJECT CEBU ISLAND L^^r SANTANM:» F\Q, 16 SILVER IN STREAM SEDIMENT LEGEND CMNGJANTAVAN Ut SYMBDL pgjJJ-s N WSTDGRAM

0.21 056 1.51 2.49 4.09 N » SO 30 XFREOUDCY Cut point values in parts per Million I N - number of samples SDGDt

I CATHM

g * • o

% »

• CEBU err . . .Jfty/«*aMACTA N ISLAND

« 9

6.7 0 6.7 1&4 kM. 8 •! 111.]

• *

HAlMfJnXf * • •/

MUVTILAI //I y DSI.DS PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PROJECT CEBU ISLAND

Fig. 17 SILVER IN HEAVY MINERALS BAANEBANTAYAN 1 LEGEND o •/ 7? SYMBDL p^Jjj N HISTOGRAM

1L64 P • W •ecu o ia88 m o »« 43 , ANAPAAJ • 3a" » p# oj 49.66 % Jo JTABCGDN N • 7 fI . . . 10 20 3D % ZFROUCNCY 1 • f Cut point values in parts tf iDRJDN TARJtXAl/"* \ per million

N - number of samples Jo oCGDD •o 1 CATMDN / * ••

9 • 1

ASTUR1AS /"J'^ •

• • J DANAD CITY \ o * ° /// . % s. * 4• J I • ° #• * • • #} 1 L.TLDAN TOIEM] CITY /• - « X • • * "9 ^*^V Jt IT °'. eEK, xy^^ - Co • # #/, c 2 7 {* i> 'i» • y»f 'V/ MACTAN ISLAND 1 • • K %• ^ /*2%,T • o,«*y/ •*" TAUSA

I 0 0 ©1 I" 1 " 1 1 ^> • •/ f • " $ RM (?'***/ * I** **7 L/ • # ° "T( 1 J,) DAl.AGUETE

ALKSPIAt IJ / JJ ALCCY r* /

KALAJUYW* ft jy 1 • •/ / • y J • M V G1NATILAW # -y 1 J'JSi.Uh PHILIPPINE NUCLEAR RESEARCH INSTITUTE 1 1 j^^ URANIUM EXPLORATION PROJECT CEBU ISLAND l^^^^^^AWTANflEK Fig, 18 COBALT IN STREAM SEDIMENT LEGEND y SYMBOL pQjJrj N WSTDGRAM

2W8 45 45.92 J? 67.30 ~ 9a63 IN

MACTAN ISLAND

6.7 0 6,7 114 k*f. f I I J

AlEGRIA,

OWATn, PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PROJECT CEBU ISLAND SANTAWBER FIQ. 19 COBALT IN HEAVY MINERALS PNRI B(EA)89001 Page 51 and 67.30 ppm. The Sapang Dako River area registered the highest values in both the stream sediments and heavy minerals, and this could b^ related to the mining activity in the area. An extensive area north of Cebu between Anapag and Tabogon showed six anomalous values in stream sediment. The high values of cobalt in this area could be associated with the manganese anomaly mentioned in earlier discussion. Another extensive area near Tubigmanok drained by the Guinabasan and Caridad Rivers pinpointed six anomalous values in stream sediments. The occurrence of serpentinite peridotite as diaphyric intrusive bodies in the Tunlob schist and Pandan series found in the area may explain the high values of cobalt.. Two samples taken from the upper left tributary of Putat River, south of Tabuelan gave anomalous values of cobalt. This may also be a result of ultrabasic rock association.

The Tapon River area yielded four anomalous values in heavy minerals. These values may be attributed to the weathering product of the overlying Carcar member. 4.5.7 Nickel Figure 20 shows the distribution of nickel in stream sediments. The areas delineated by the anomalous values (>58.82 ppm) are found in the Anapag-Tabogon area, Putat, Languyon, Guinabasan and Balamban Rivers, and at the upper tributaries of Talisay River. Tne Anapag-Tabogon area that yielded twelve anomalous values is characterized by the Carcar and Barili LEGEND MNCMNTATMt SYMBOL p&Jre N HISTOGRAM

n o* «* » e 2635 o 4229 "J o 5832 * r*» • 7*38 » iTAnCON N

Cut point values m ports \ per MlUon N - number of sonples

• fi mvwo CITY

t o)

TOUBO CITY • :

CE»U.

MACTAN ISLAND

.<* TAUSAY

• * 00

DUHWJUG fCASCAR

* # ISUONGA 6.7 0 6.7 OA 1 1 I J

• **

k * *

f 9 I • J BAI.AGUETf ttx&mt j IALCOY

MLAIUYOCP A ^ 1 • 7 1 * 7 r '

Fig. SO NICKEL IN STREAM SEDIMENT PNRI B(EA)89001 Page 53 formations. The other areas delineated by high nickel values may be related to the replacement of the ultrabasic igneous rocks. Figure 21 shows the distribution of nickel in heavy minerals. Host of the areas outlined by the anomalous values (>81.28 ppm) are considered as point anomalies. A single anomaly together with two above background values (>20.55 ppm) in the Handawe River area may suggest that the higher than normal values of nickel in this area could possibly be due to sulphide association,^considering that the area is also anomalous in copper, zinc and silver. 4.6 Correlation Between Elements To get information on the structure of inter-element relationship, the Pearson linear correlation coefficient was used between all element pairs. This measures to what extent one element varies either sympathetically or antipathetically with another and this may help to predict the type of mineralization present. Also, this technique is useful in exploration wherein one element could be used as an indicator f^r the presence of the other.

In both the stream sediments and heavy minerals, uranium does not correlate with any of the other seven elements. The highest correlation coefficient obtained in stream sediments is between cobalt and nickel (+0.703), This means that cobalt and nickel are posit.'ve indicators of each other in Cebu. The other significant elemental associations established by the stream sediments are Mn-Co-Ni and Mn-Cu-Zn. The Mn-Co-Ni association could be a product of weathering in which Mn together with Co and Ni were LEGEND SAMKMHTAYAN 1 ^T

SYMBOL pgjJTS N HISTOGRAM 82? ?J u 2055 jj •00Q j 0 51.40 ^5 , h 8L28 » ° 12a53 8 / i • 1 (TAKOM N » a » * XFUEOUDCY 1 • f Cut point values m ports TNURJif • 7 BORWN per million T

N - number of samples / * ° 2CGQS

dCATMON

^ \ ° / ° »*l ASTURIAS r I • .8 • • ° o 1WVM0 CITY I* • e J o

A * Ot 1 ULIMN TOLEDO Cm J* ft # * ^ • «» • • V~~SJ A' * V f CESU _ /O^"^ J 9 'f •IACTAN ISLAND // • o f^V -^TAirSAY /' * VrMQA

•*R!Lrl# _ / AT * ° f y # " vJ «*MNJUG/ foWOW / * 8,/ «CMTMA\ * ISIMNGA 6.7 0 6.7 1*4 kns. 1 1 1 1 V • °1 s • •/ 1 ' • •> 1 * J f * 1 1 * ( 1 V 0AL»GUETE

AJIGPIAP f / 1 ALCDY /* / (MIJttUYtt* « / 1 • Y

f * / iVMTIUNh / T /[BUM PHILIPPINE NUCLEAR RESEARCH INSTITUTE URANIUM EXPLORATION PROJECT CEBU ISLAND ^^^/SAPfTMSCR Fig. 21 NICKEL IN HEAVY MINERALS PNRI B(EA)89001 Page 55 formed as weathered residual laterites (see Figs. 14, 18 and 20). The Mn-Cu-Zn association could not be ascertained in the present investigation although it could be surmised that the increase in concentration of Cu and Zn where the value of Mn is high was brought about by Mn absorption of Cu-Zn ions in the sediments as discussed by Flores (1982). The elemental association established based on the correlation coefficient in heavy minerals is Cu-Pb-Zn-Ag-Co-Ni. This significant relationship could be partially attributed by the polymetallic hydrothermal mineralization as evidenced by several overlapping higher than background and anomalous values of the six elements in the Mandawe and Talisay River areas. The seemingly different elemental associations established in the stream sediments and heavy minerals could be attributed by the absence of heavy mineral samples particularly in areas where several overlapping anomalous values of Mn, Co and Ni, and Mn, Cu and Zn in stream sediments occur. Also, this is further shown by the insignificant correlation coefficients between the stream sediments and heavy minerals in each element (see Table V).

TABLE V CORRELATION COEFFICIENTS BETWEEN STREAM SEDIMENTS AND HEAVY MINERALS IN EACH ELEMENT BASED ON 154 SAMPLES Stream Sediments

: u i Cu ! Pb ! Zn ! Mn ! Ag ! Co ! Ni ! Heavy Minerals ! 0.141! 0.367! 0.259! -0.024! 0.055! 0.353! -0.115! 0.246! PNRI B(EA)89001 Page 56

5. CONCLUSION AND RECOMMENDATIONS The present investigation has shown the effectivity of geochemical exploration coupled with radiometric survey in outlining areas of interests for possible uranium mineralization in Cebu Island. Four areas were delineated (see Fig. 22) and these are listed in the order of priority as follows: 1. Mandawe River area: with strong radiometric anomaly, high uranium contents in heavy minerals, moderate uranium contents in stream sediments and above background values of radon in stream water. Favorable geological environment for possible uranium mineralization would be the contact zone between the diorite and the sedimentary Mananga formation. This is similar to the Larap uranium deposition. Possibly, the diorite itself may contain enough uranium that may be of economic interest.

2. Barili-Carcar-Pinamungahan area: with high uranium contents in stream sediments, above background to anomalous radiometric readings and several above background to anomalous uranium contents in heavy minerals and stream water. The anomalous values of uranium in this extensive area could be possibly be related to the phosphate and guano deposits. 3. Talipon Creek in Daangbantayan area: a point anomaly with the highest value in stream water, high radiometric reading, high uranium content in heavy minerals and above background value of radon in stream water. 4. Carmen-Catmon area: this area north of Danao City gave very PRIORITY AREAS FOR FOLLOW - UP SURVEY APEA 3

AREA 1 - MANLAUe RIVER AREA

AREA 2 - BARILI-CARCAR- PINAMUNGAHAN AREA

Arffrt J - TAU^N JSCtK !f<

-10* «r -

30 hn

124* l Fig. 22 DELINEATED AREAS FOR FOLLOW-UP SURVEY PNRI B(EA)89001 Page 58

high values in stream water. However, results of the other media of survey gave low values hence, resampling should be conducted in order to check and verify the source(s) of the high values in stream water. As for the other seven elements, the following areas were delineated: 1. Mandawe-Upper Talisay River area for copper, zinc, silver, cobalt and nickel. Part of this area was also delineated by uranium. Polymetallic hydrothermal type of mineralization is a possibility in this area. 2. Carcar area for copper, lead and zinc. Uranium was also delineated in this area. 3. Talisay area for copper and zinc. This area is similar to the Atlas mine copper deposit. 4. Anapag-Tabogon area and the anomalous zone drained by the Putat, Languyon, Guinabasan, Caridad and Balamban Fivers for manganese, cobalt and nickel. The lateritic type of deposition could be the most probable form of mineralization in this area. 5. Argao River area for manganese, zinc, cobalt and nickel. 6. Dalaguete Fiver area for manganese, cobalt and silver. Since there is a marked discrepancy in the inter-element relationships in stream sediments and heavy minerals, no definite elemental association could be established in the present study. Insofar as uranium is concerned, it is found to be not related to any of the other elements analyzed. PNRI B^EA)89001 Page 59

Considering the potential of Cebu for uranium mineralization, it is suggested that follow-up surveys for the delineated areas particularly areas 1 and 2 should be undertaken. It is also significant to note that the utilization of Q'GAS, Cadplot and Autocad had greatly improved and facilitated the evaluation and interpretaion of exploration-oriented geochemical and geological data. More importantly, the production of computer-generated geochemical maps is considered a first in the country.

6. ACKNOWLEDGEMENT The authors wish to extend their most profound thanks to all the officials, friends and laborers who in one way or the other contributed to the very successful implementation of the survey and for this report to materialize. This activity of the project on nationwide exploration for nuclear raw materials is indebted to the International Atomic Energy Agency (IAEA) for granting through its Technical Assistance Program a microcomputer system complete with the necessary peripherals and softwares to PNRI. PNFI B(EA)i39001 Page 60

7. REFERENCES Barnes, H. , Jongco, C. P., Lasaga, G. C, Pilac, J. E. and Vokes, H. E., 1955, Geology and coal resources of the Argao-Dalaguete region, Cebu: Phil. Bureau of Mines. Boyle, R. W., 1982, Geochemical prospecting for thorium and uranium deposits; Developments in economic geology, 16; Elsevier scientific publication company, 498 p. Cameron, J., 1965, Prospecting and evaluation of nuclear raw materials, Report to the government of the Republic of the Philippines: unpublished. Corby, G. W., et al, 1951, Geology and oil possibilities of the Philippines: DAMR Technical Bulletin No. 21. Flores, W. C., 1982, Cu-Pb-Zn-Fe-Mn interrelationship in some copper base metal prospects in central Cebu, Bureau of Mines & Geo-Sciences, Cebu City: Geological Exploration Series No. 82-1. Jagolino, R. B., 1960, Preliminary report on the geological investigation of dolomitic limestone in Cebu City; Bureau of Mines RI no. 27. Lavin, 0. P. and Nichol, I., 1981, Q'GAS: A minicomputer-based system to aid in the interpretation of exploration oriented geochemical data, Jour. Geochem. Explor., 15 p. 521-537. Park, Jr., C. F. and MacDiarmid, R. A., 1964, Ore deposits; San Francisco and London, W. H. Freeman and Co., pp. 378-379. Smith, A. Y. and Lynch, J. J., 1969, Field and Laboratory methods used by the Geological Survey of Canada in geochemical surveys, No. 11, Uranium in soil, stream sediment and water: Geol. Survey Can. Paper No. 69-40. Tauchid, M., 1978, Reconnaisance geochemical survey for uranium deposit in Samar, Report to the government of the Republic of the Philippines: unpublished. Bureau of Mines, 1976, A review of oil exploration and stratigraphy of sedimentary basins of the Philippines: UN-ESCAP, CCOP, Technical Bulletin, vol. 10. Japan International Cooperation Agency (JICA) and Metal Mining Agency of Japan, 1987, Report on the mineral exploration: mineral deposits and tectonics of two contrasting geologic environments in the Republic of the Philippines, Phase III (Part II); Cebu, Panay and Romblon area, No. 29. PNRI B(EA)89001 Page 61

1:50,000 Compiled Geological Map of Cebu Island: Bureau of Mines and Geosciences, 1983. PNRI B(EA)89001

APPENDIX PERCENT OF THE TOTAL SAMPLES PERCENT OF THE TOTAL SAMPLES

15.0 30.0 45.0 60.0 75.0 ...»— —f— —• 0.0B4f [ 0.117f

0.163

0.228

0.318 n I 0.445

0.621*™ M 11 0.067}!

,m|L 4— —«.. —• 15.0 30.0 45.0 60.0 75.0

PERCENT OF THE TOTAL SAMPLES

PERIENT OF THE TOTAL SAMPLES

o c •a a

184,502

Appendix i FREQUENCY DISTRIBUTION OF URANIUM, COPPER, LEAD AND ZINC IN STREAM SEDIMENTS PERCENT OF THE TOTAL SAHPIES PERCENT OF THE TOTAL SAMPLES

10.0 20.0 30.0 40.0 50.0 5.0 10.0 15.0 20.0 25.0 —4 4 4 4 4 —»— —•-- —4— 4— 4 3.475}; 7.53*i; ii 4.426}" 12.162}' i 5.636} 19.634} 7.178}

5C 9

•d B

PERCENT OF THE TOTAL SWIPLES

10.0 20.0 30.0 40.0 50.0 ... 4— —4— 3.319}" 4 it 4.310} 5.598} PERCENT OF THE TOTAL SAMPLES 7.269J, 9.441} 10.0 20.0 30.0 40.0 50.0 —• • • • • 12.260 imn 0.129 « 15.922 It 0.202 20.678 nfflniiHfflnlllHHHI 0.3164 as 26.853 HHHinllHml M 0.493 HMHMMHUIH 34.874 •xt 0.771 HI iHiiniiHiiiiiiiMMHflMflf i B II 45.290 IIIIIIIIIH 1.205 58.817 fffffllH 1.8B4}

76.384 imn 2.944 IHHII —t— —-• — ... 4— —4-. —• l 10.,0 20.0 30.0 40.0 50 10.0 20.0 30.0 40.0 50.0

Appendix 2 FREQUENCY DISTRIBUTION OF MANGANESE, SILVER, COBALT AND NICKEL IN STREAM SEDIMENTS PERCENT OF THE TOTAL SAMPLES PERCENT OF THE TOTAL SAflPlES

0.225} i O.Jttf

1221.799) —4 * 4 4 ------—•— 1 10.0 20.0 30.0 40.0 50.0 5.0 10.0 15.0 20.0 25.0

LONER PERCENT OF THE TOTAL SAKPLES BOUND INCLUDED . 10.0 20.0 30.0 40.0 50.0 1

PERCENT OF THE TOTAL SAMPLES 0.415}! 11 10.0 20.0 30.0 40.0 50.0 0.804}, —*-• —•— —•-- —+ 4.529} i| i 1.554}; il 7.9434 3.006}! 13.932} I" 5.814} 24.434} o 1 II 11.246} 42.655 11 -0 21.752} 75.162 II 1 42.073} 131.824 81.377}' 231.207 1 157.398} 405.509 304.439} 11 711.214}. 588.844}: II 11 1247.383}| 1138.938}! ! ... 1— ... — —• ------t —•« —•------— • • 10.0 20,0 30.0 40.0 50.0 10.0 20.0 30.0 40.0 50.0

Appendix 3 FREQUENCY DISTRIBUTION OF URANIUM, COPPER, LEAD AND ZINC IN HEAVY MINERALS F-EhCEMI OF THE TOTAL SAHPLES PERCENT (If IHE TOTAL SAttfLES

10.0 20.0 30.0 40.0 50.0 —t— —•— —•— —«.. —• 37.068}" it 65.615}! iP 116.145} I 205.589} I 363.915} I 3f 644.169} i| 1140.250}. -v 11 3 2018.367}? 11 3572.728}: iP 6324.117} i 11194.373} i 19815.268}

—•-- ...... —+— —• 10.0 20.0 30.0 40.0 50.0

PERCENT OF THE TOTAL SAHPLES PERCENT OF THE TOTAL SAMPLES

20.0 25.0 10.0 20.0 30.0 40.0 50.0 • 1 —• • • • • 0.13&L II 0.217}" i 0.346} ES > 0.552} m I II 0.881} M •xi I, vJl Tf 1.406} •*» 3 vfl 2.244} ii 3.5811! |l 5.715}

ii. —•-- — •-- —* 10.0 2O.0 30.0 40.0 50.0

Appendix 4 FREQUENCY DISTRIBUTION OF MANGANESE, SILVER, COBALT AND NICKEL IN HEAVY MINERALS i i N = 170 H = 159

I i i

*> r« ~ o rs to £. —^r^-oforofor-.oR K 2 S - r-> r-o «> c» o Radon (cpm) U (ppb)

00 O *•? _• —< _< _< r>4 rvi r J fj r<->

Scintillometer Readings (cps)

Appendix 5 FREQUENCY DISTRIBUTION OF RADON AND URANIUM IN STREAM WATER AND SCINTILLOMETER READINGS WISH 0.402 0.734 0.871 1.09$ 1.13* 1.273 1.4 .542 1.474 1.810 l.*44 ft.I... I.l„. .„_ I I I ...... 1 ...I..-I . •„_ I...... I... ..!# 48.000 t ; 1.8JJ

2 I R = 0,703 II I J 22 38.585 l»M6 I 2 2 I I 4 I I 2 l> t I 3 13 13 4 2 1 I 21 1 3 2 3 43 341212 I

21.874 2 8 J 8 2 2 42 1.340 Ml 1106 LC8SFI 8 8 A » 4 3 I 2 I I IC0SE0

I C 4 4 2 I 12.423 1.0*4 I 8 8 4 1

$ 2 I 7.049 0.848

0.402 4.000 j? i i i i i i i. i—: i i i 1» 4.000 5.44* 7.422 10.111 13.773 18.742 25.557 34.814 47.424 44.401 B8.«00 ANT HOG LMISE8) Appendix 6 Scatter plot of nickel versus cobalt in stream sediments. * = 1, fc = 10-11, B = 12-15, C = 16-20, D - 21-30 LCUSED -0.398 -0.122 0.153 0.42* 0.705 0.980 1.254 1.532 1.807 2.083 2.35* i i i 1 i i i . i i i ^ 217.400 -I 2.338

R = 0.622 107.48* I , » 12 2.031 1 - Mil* •• i HI1 "?'i i

53.097 1.725 Ml!1106 UKSED . .Br • L7HSEP

26.276 • . \ 'JXJVV 1.1 m 111 1.41* 8.. !• .• : • ,»2 i ii I2.*54 ;l Sii'r. i iS in I 1.112

4.400 »i 1 1 ..i :—I t . i 1 1 ...i.... i 11 0.806 0.100 0.755 1.474 2.484 5.047 9.558 18.032 34.018 44.175 121.06* 228.400 WtTHOG ICUSEO Appendix 7 Scatter olo* of copper versus zinc in stream sediments' 0.993 \.m 1.47J 1.757 2.042 2.327 2.411 2.894 3.181 3.4M 3.750 • •- 717.M>0 - 7.331

M t R = 0.621 107.4W I III I I 2.031 ' l •fib*'/ •. tii. i."'I: '2 t • • • • 53.097 1.725 MI UK • 2' l» I2 ' I ' » « I2 » ' I7HSE0 HUSH i } •!• 3| 12 7 i1 » il :•, 24.271 1 "" i'! 1! 'TI i' "'• '• • 1.419 J' «i," '•» }' 2 «» » 2 iii M III 17.954 11 i i i ii 1 1 r » 1.112

4.400 1 0.804 . B.OOO 15.410 79.485 57.183 110.153 717.189 408.741 787.343 1514.704 2921.444 5478.W0 ANTR06 INKSfO Appendix 8 Scatter plot of manganese versus zinc in stream sediments

IIMSEI 0.903 1.188 1.473 1.757 7.047 7.377 7.411 7^894 3.181 3.444 3.750 ji i i i i i 1 1 1 1 if 48.000 I I 1.833

II I "II R = 0.609 771 2* I ll 38.585 1.584 137 7 71 121 II I I77744III I I II I I 13 134743137 I II I I I III I II 77 III7II7I3 13 II 71.894 1,310 MTI106 I I 711 33 71 73371111411431 I 7371317 UOSEt LC0SEI I III 3 M75II4 I25l2352il 3221 21 22321 3

12.473 1,094 I 2 122 I I 3 3III223H3I43I33II III II

II III II I 2 2 I 171 71 I I I 7.019 0.848

•

2I • 1 •! t R = 0.«588 • tn h • H 47.424 t, A; 23|32JI«; ., 1.474 I «. I 2112 112 12 2 23 124 2 2 2 II 2 till 2231 I 421 322 I t I 75.557 II II I II I 32 22213 333131354 14122 211 MTP.06 II MISC8 II 4111 3 1311 1332422312! 112 I I 131 I WISH

I 122 2 3 I 3112 I 112 2 2 I I I 13.773 .139 I I I I I 2 2 113 I I I I tt

I I I 12 7.422 0.871

4.000 »• 1 1..1I 1 1 ! I 1 1 1 1 1 j 0.402 8.000 15.410 29.485 57.183 110.153 212.189 408.741 787.343 1514.704 2921.444 5428.000 ANTIL06 LIWSEP Appendix 10 Scatter plot of manganese* versus nickel in stream sediments LWSED 0.804 0.959 1.112 1.244 1.419 1.572 1.725 1.878 2.031 2.185 2.338

88.000 1.944 1 ||t III 1

R = 0.564 M 1 2 V i " ' 1 1 47.424 «II,!J.2|,!¥,!,I • 1.474

1 w 112 1 t «•'••• M • • • 12 II 1 212 212 21 217 12 II 1 t II 1 11 22 1 12 3 12 1 2 3 IM II 121 1 1 25.557 1.408 1 1 1 21123 I3II3I 32 2232IIII3 3 1 21 II2II2 1 1 1 ANTIL06 WISED 1 1 I2III2 21 4112 121 1 11132123112111 II 2 III 1 III LN1SEV 1 III 2 II I 2 1211 I 122 I III 13 MM 13.77J 2 I 1112 M2I 2 I II I f 1.139

I I 7.422 0.871

MM;, , I, M, , , , , , , ,; 0.402 6,400 9.104 12.954 18.434 24.228 37.318 53.097 75.547 107.489 152.934 217.400 AKTIL0S LINSED Appendix 11' Scatter plot of zinc versus nickel in stream sediments LIWSED 0.703 I. IBB 1.473 1.757 2.042 2.327 2.611 2.896 3.181 J.466 3.750 »i 1 1 1 1 1 1 i i i ,, 228.4f>0 - 2.35?

! «ft R = 0.548 J» K I ! M 64.175 1.807

i » iVV Pifc i »•

18.032 1.256 MTIIK ». i. Jv,m m I. I » i». icusn LCUSEB •:. i : it2 i I ' 'ij I « i I r j-1 • • Si» 5.067 ;t I It II . .12 I i »r 0.705 i i • t 11 i 1.424 H i i i 0.153

0.400.;, 4. —i ..I i i.4: ...i i 1^ -0.398 8.000 15.410 29.685 57.183 110.153 212.19? 408.741 787.363 1516.706 2421.646 5628.000 ANTIL06 LHNSEO Appenflix 12 Scatter plot of manganese versus copper in stream sediments HUSH 0.806 0.959 1.112 1.266 . 1.419 1.572 1.725 1.878 2.031 2.183 2.338 11.., i...... i ...i . .i. i...... i .... i...... i...... i.-...--..•» 6B.0C0 1.833

1 2 R = 0.527 II t I I * hi i 38.585 1.586 I lilt I 112 II 41 I 112 12 43131! 2 2

I I I I III MIII5 322 II I 2 I It I 2 12 1 3 321 113 I 2 I 1112 I 21.894 1.340 ANT 1106 II I 2 2 I 2II2III 21122 I 121222 23 2 11321 12 1 I I LC05ED LC0SED I { It 131 I 41 113122 2321232235 122 2(31 1121 Mil 2 I

12.423 1.094 I I 21 til 221 3421211 52I2II2I3 131 2111 1112 It

I I III III 4 Ml 2 I 2 t I 7.049 0.848

0.602 4,000 41 i i..I t: .i :..i—;I i.. i 1 1 1 > <• 6.400 9.106 12.956 18.434 26.228 37.318 53.097 75.547 107.489 152.936 217.60 ANT 1106 L7JSED Appendix 13 3catter plot of zinc versus cobalt in stream secliments INIHN 0.402 0.755 0.908 1.0*2 1.215 1.348 1.321 1.471 1.827 1.980 2.139 (i 1 r 1 1. i i .„ i . i i_.„.

114.000 ; . . . . . f . . 2.044

R = 0.815 59.153 J. 1.772 1 1 1 3 • » l2

1 3 I 1! I I «•• 1 2 1 III 30.145 1.479 2 12 1 AN!1108 1 3 2 2 2 (.COWl LCOHH 3 3 2 4 I 1

7 1 3 3 1 1 15.382 1.187

2 I t

7.844 ;7 0.89}

*-m;1 ? , • , , , , , ,j 0.402 4.000 5.491 B.09B 11.521 14.393 23.324 33.185 47.217 47.180 95.585 134.000 ANT 1106 LNIHH Appendix 14 Scatter plot of nickel versus cobalt in heavy minerals

IZWffl 0.748 0.992 1.237 1.481 1.725 1.949 2.213* 2.457 2.701 2.944 3.190 »p i i i i i i i i i i» 114.000; I ; 2.044

1*2 R = 0.729 1 2 ' 59.153 I I 1.772 I I III I III | I I I

I I I » «l ll I I I II 2 211 30.145 1.479 I I II 2 I AHtlLOG I III I I II II LCOHH UOtffl I I 21 I I 12 211 3 I I 221 2 2 II 31 I I 15.382 1.187

2 III! II I 2 2 II I II

7,844 :l 2 I II 2 I III III 0.895

«•*•;!„.«!.?., !-. »!.. . • -J 0,402 5.400 9.825 17,239 30.244 53.047 93.104 143.3)7 284.413 302.848 882.293 1)48.000 ANT 1100 lIMffl Appendix l*> Scatter plot of zinc versus cobalt in heavy minerals UNHM 0.748 0.992 1.237 l.*Bl 1.725 1.969 2.213 2.457 2.701 2.946 3.190

«• 1 1 1 1 1 1 „.i i t ,, 1898.000 lr 3.257 I

R = 0.647 ' 1 • • t I 532.317 2.726

I t ," » 156.727 2.195 ANTH.06 ' I I I • " 2 I mm I LPMtt A i • v v :• • I I 46.144 ,M 11 u : 1 t t I 2 .•! I. 't • 1.664 II 1 ,»,V III 112 7 112 I 2 It II I 13.586 II I 21 II 1.133 2 2 1 II I III

4.000 -7 I I 0.602 5.600 9.825 17.239 30.246 53.067 93.106 163.337 2B6.6I3 J02.B6B B82.293 1548.000 ANTIL06 Lim Appendix lf> Scatter plot of zinc versus laad In heavy minerals LCOWI 0.602' 0.748 O.B93 1.041 1.187 1.333 1.479 1,626 1.772 1.918 2.064 i i i i i P t 1 1 1 "• 7.600 ; 0.881

R = 0.643 3.672 0.565

I I I I I 12 11 I 0.249 1.774 2 2 2 1 I 12 I! ANT 1106 LABWI mm 3 3 12 2 1

0.857 -0.067 3 I 53 3313 2211

0.414 ;3 4 4 3 12 2 2 1 -0.383

o.MOjt , ,» ,„! ,? L,„! ?_,.!... , , .; 0.699 4.000 5.601 7.844 10.984 15.382 21.541 30.163 42.241 59.133 82.836 116.000 ANT 1108 ICOWI Appendix 17 Scatter plot of cobalt versus silver in heavy minerals urn* 0.748 9.117 1.237 1.481 1.725 1.96? 2.213 2.457 2.701 2.946 3.190 <.. t .- -l I I„ I.... l „ I . I . 14 136.000 !' 2.134 I . , ' .' R = 0.642 I 67.100 V 1.127

• i • • A • • • 33.183 2»2 1.321 „• I • ,1,1111,1 AH!1106 LNINH 12 1 III II 2 1 mm I I I I I I I III II I 16.393 I I I I I I II 1.213

21 Kill I I 2111 I II 12 I

8.099 ; I 111 III I it i 0.908

i.ooo jfiii2i2, i,i iii|!!„! i„.„!!„, ,.„ , , , ,; ••*•* 3.600 9.825 17.239 30.216 33.067 93.106 163.337 2B6.613 302.868 882.293 1348.000 ANTIL06 LtWffl Appendix 18 Scatter plot of zinc versus nickel in heavy minerals LZMdt 0.718 0.992 1.237 1.481 1.725 1.969 2.213 2:437 2.701 2.946 3.190 „„i i...... r... „ l...... i ....I .( . ...I...... I.... .if 7.600 T I • 0.881

R = 0.642 I I 3.672 0.363 I I

1 t 1 2 1 1 III 1 1.771 0.249 1 1114 II 1 1 ANTlLOe M6NH IA6WI 2 2 III 2 II I

0.837 -0.067 I I I 2IU II 2 II 1131 III2II I I

0.414 : I 2 I 2 IHI2 I II t 31 12 I II I -0.383

, M0 M - ;f..!!?!.????-?!?.?!??.!...!????!!J!...f!!.„!..!f! i ( ..! .; "°-* 3.600 9.823 17.239 30.216 33.067 93.106 163.337 286.613 S0i,B6B 132.293 1548.000 ANTIL06 LlMffi Appendix 19 Scatter plot of zinc versus silver in.heavy minerals INIWI 0.602 0.759 0.908 1.062 1.215 1.348 1.521 1.474 1.827 l.fBQ 2.13»

ti 1 1 1 1 1 1 1 i i i, 7.600 I r 0.881

R = 0.585 2 3.672 0.565

III t I I 3 I 1.774 0.249 12 12 2 AKTtUffi I V. tASHH II 2 3 I I II 2 LAoffll

0.857 -0.047 2 2 551332 III I

0.411 ;3 3 7 2 3 2 112 2 -0.383

••»•;? • .! *...„.»-.« ?..„J_„, , .; -°-H' 4.000 5.691 8.098 11.521 16.393 23.321 33.185 47.217 47.180 95.585 134.000 ANTIL06 LNIHd Appendix 20 Scatter plot of nickel versus silver in heavy minerals um 0.748 0.992 1.237 f .481 1.725 1.969 2.213 2.«7 2.701 2.941 3.190 f I. I I . I I I .1 ...... I..-.-__..!. !.-. ... If 1908.000 3.281

n = 0.584 I 350,651 2.545 I •1 I I I ! m r i i i 2 I

M 61.142 '. l' I, 12 » l. I 1.809 I I ANT 1106 •"•"*• M I !! i j ICIWI 2 i' I I II l?V ICMW I I III 2 I ,1* | ,IMl •• J ;i •! Ii ,• ! I i.i .i •. 11.813 T • 1.07 J I I 2 I I I I

2.177 : I 0.338

M00;f ?., , , , , .i i i 14 -\39i 5.600 7.825 17.23? 30.246 53.067 93.106 163.357 286.613 502.868 S82.293 1948.000 MTILOS UNHK Appendix 7\ f.catter plot of zinc versus copper in heavy minerals ICIMI -0.398 -0.030 0.3J8 0.706 1.073 1.441 1.809 2.P7 2.545 2.913 3.211 A I I „ | . | I „„ | | „„„ | | .„ | „ | » 1808.000 - . I 3.257

R = 0.547 tl 532.317 2.726

156.727 ; 2.195 1 ANTK06 j I I * IPWH • LPIHH , , I 11 tit

46.144 i I «.«i, . I '"' • I I. , I tt I1 I 1.661

t II til I 2 It II It It n.m T I I I tl I t 1.133 I I III I I 12 I

4.000 ;2_ t I -•• 0.400 0.933 2.177 5.077 11.B43 27.626 64.442 150.322 350.651 817.949 1907.999 0.602 AUTILOG LCUHH Appendix 22 Scatter plot of copper versus lead in heavy minerals ICOHtl 0.602 0.74B 0.89) 1.041 1.187 1.333 1.479 M.626 1.772 1.918 2.061 i i i i i i i i i • 1908.000 ;' • I ' 3.281

R = 0.538 350.651 2.545 I t i I, ? 64.442 I I 'i ' 1.809 ANT 1106 2» I ' LCUHH LCUHH i ; 12 t

11.843 \ ! 1.073

2.177 0.338

M00 ji ,_„ i i i i i i i— -i 1« -0.398 4.000 5.601 7.841 10.984 15.382 21.511 30.165 42.241 59.153 82.836 116.000 ART [LOG ICOHtl Appendix 23 Scattter plot of oobt.lt vermis copper in heavy mineral*