main contributor I& a sample collected) &oserI. +o the mineralisation [SJ 241 2501 was not anom&~+ The occurrence ofcopper mineralisation in the Moelydd intrusion prompted the water sampling of., springs and streamlets in the ‘area to improve sample cover, fQr
. which could be responsible for the!: minetialisation “at Llangynog. The relationship,. if ttny, of the known mineralisation 1 ’ ’ tti the ‘Bougue3. ‘anomzilies remains obscure. More detailed gr&ity *surveys ‘of specific Bouguer anomaly features, such as’ those near Craig-y- Glyn [SJ 10 301 and the low northwest of Ll&ngynog [SJ 03 281, are required to determine their cause Bnd possible relationships to nearby mineralisation. * 1 *., ;I’: ; (jj..’ : \ . * -.. ACKNOWLEDGEMENTS , .‘! :; * . . I ,‘.;b’ ;, ,r: Mr P. M. i Green and Mr N. lBell collected many.:of the drainage Samples. and: Mr P. J . Bide helped ta process the geochemical e data. Sample preparation and chemical analysis was carried< out by staff of the: ,Analytical Chemistry Unit of BGS, and staff of the Drawing Office,, BGS, prepared all the diagrams in the report. . ! I -, * . . i ,. *:i ’ ? a REFEBENCES a j d , ;- * ALLEN,-P. M., COOPER+ D.‘C. and SMITH, * .‘... :..:‘: s I. 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