Reconnaissance Geochemical Survey for Uranium and Related Industrial Minerals in Cebu Island
Total Page:16
File Type:pdf, Size:1020Kb
PNRI B(EA)&<J001 RECONNAISSANCE GEOCHEMICAL SURVEY FOR URANIUM AND RELATED INDUSTRIAL MINERALS IN CEBU ISLAND by 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 by 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.