STATE OF ALASKA

DEPARTMENT OF NATURAL RESOURCES

DIVISION OF GEOLOGICAL AND GEOPHYSICAL SURVEYS

John W , Katz - Commissioner

Geoffrey Haynes - Deputy Commissioner

Ross G . Schaff - State Geologist

May 1982

This is a preliminary publication of the Alaska Division of Geoiogical and Geophysical Surveys and has not received final editing and review. The author wlll appreciate candid comments on the accuracy ot' the data and will welcome suggestions to improve the report.

Alaska Open-file Report 164 GEOCHEMICAL RECONNAISSANCE OF THE NORTHERN FAIRBANKS D-1 AND SOUTHERN LIVENGOOD A-1 QUADRANGLES, ALASKA; SUMMARY OF DATA ON

STREAM-SEDIMENT, PAN-CONCENTRATE, AND ROCK SAMPLES

BY M.D. Albanese

TABLE OF CONTENTS

Page

Introduction........................................... ............... 1

TABLES

Table 1. Stream-sediment samples, Livengood A-1 Quadrangle ........... 2 2. Stream-sediment samples, Fairbanks D-1 Quadrangle ........... 11 3. Pan-concentrate samples, Livengood A-1 Quadrangle ........... 17 4. Pan-concentrate samples, Fairbanks D-1 Quadrangle ........... 19 5. Rock samples, Livengood A-1 Quadrangle ...................... 2 0 6. Rock samples, Fairbanks D-1 Quadrangle ...................... 24

PLATES

Plate 1. Stream-sediment sample locations, northern Fairbanks D-1 and southern Livengood A-1 Quadrangles ................. Envelope

2. Pan-concentrate sample locations, northern Fairbanks D-1 and southern Livengood A-1 Quadrangles ................. Envelope

3. Rock-sample locations, northern Fairbanks D-1 and southern Livengood A-1 Quadrangles ..................... Envelope

GEOCHErlICAL RECONNAISSANCE OF THE NORTHERN FAIRBANKS D-1 AND SOUTHERN LIVENGOOD A-1 QUADRANGLES, ALASKA; SUP.IMARY OF DATA ON STREAM-SEDIMENT,

PAN-CONCENTRATE , AND ROCK SAMPLES.

BY M.D. Albanese

INTRODUCTION

This report lists the geochemical analyses of 478 stream-sediment samples, 99 pan-concentrate samples, and 231 rock samples from the northern Fairbanks D-1 and southern Livengood A-1 Quadrangles, Alaska.

These geochemical results present part of a geological and mineral investigation of the Fairbanks Mining District conducted by DGGS and the Mineral Industry. Research Laboratory, University of Alaska.

The samplks were collected during May-July 1981 by DGGS staff members T.E. Smith, T.K. Bundtzen, M.S. Robinson, M.D. Albanese, D.N. Solie, V.M. Ferrell, G.M. Laird, J.D. Blum, M.H. Hall, J.D. Clough, and S.A. Liss; MIRL staff members P.A. Metz and B.W. Campbell; and D.B. Hawkins of the University of Alaska.

Copper, lead, zinc, gold, silver, and molybdenum were analyzed at the DGGS laboratory by atomic-absorption spectrophotometry with a lower detection limit of 0.01 ppm. DGGS laboratory staff involved in these analyses include M.A. Wiltse, D.R. Stein, N.C. Veach, M.R. Ashwell, T.A. Benjamin, M.K. Polly, C.L. Smith, and S.W. Seed.

Tin, tungsten, mercury, and arsenic were analyzed by Bondar-Clegg & Co. Ltd., Vancouver, B.C. Tungsten and arsenic were analyzed by coulometry with a lower detection limit of 2 ppm. Mercury was analyzed by cold-vapor atomic-absorption spectrophotometry with a lower detection limit of 5 ppb. Tin was analyzed by X-ray fluorescence with a lower detection limit of 5 ppm.

The geochemical data were sorted and plotted by using computer programs written by Alyce Egan and Otto Johansen. G. Hall and J . Lindhorst assisted in checking the data for accuracy.

,&lmp,J,-,--- - - v F - - - - - - - - - - - F - F - - - - V - - 7 7 - 7 - - -

V V V V V V V V V V V V \ J V V V ' 4 V V V V V V L ' V V

W N N r l j p J - ~ N N - - - r o ~ - - - - - - - - - T - - F - - ? - F - - N - - - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O O O O O C 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

v V v V v v v V v V V V

Table 1 -2-

0 0 \ m O O c O W N C U P d N N N - - - O N N L n L ? L n u 3 O ~ ~ a \ ( r J 3 3 0 L i > ~ - b F C O ~ C-GO c - - - - - - - - - - - ~ ~ ~ ~ - ~ - ~ c F F F - F c F - - - F - - ~ N C J

Table 1 ( c o n t . ) -3-

3 O O ?- 'a03 F J( -QMLninLnCbLL l =(-a b - o C . 7 L 1 U 3 U 2 G OQL-LnO - c r j C J O C 2 r mbt-O J 3 r iU Cn 3 Ln - P i J d - Li? 3 3 Ln Ci: CJ 07 GI F C\] :',? ti7 ti-) L7 Ln

5 3 ; r X C d C U ' . O ~ t - C - - t - I - - C - - P - h L L l U 3 u 3 ~ G \ C Q \ O L ? L A 7 b > L ~ ~ i S c 3 : r 3 C-!J7C'rC\;r U > 3 J Z - L ?

T a b l e 1 (cont .) -5-

Table 1 (cont . )

-6-

I I I

3 I 0 I

I I I 1 I I I - I - - I - l

1 ' 3 I c I 0 I A I

07 I I

2 I a. . . 1 . d I c< I 5'2 - I

I b -.-

- l - I - '

-c, I L- - m i - J I t-I I ci I L; i-j - I

I , - .' ' 1

,a w t *-: LL r- I LA 2. 1 z z 2 1 €+ H (3 1 m u 69 l

& ! - w n 1 - . . . . . C O O O G

2- o b a o o V- C,J ,* - ZT P- -.3 CT 0 CJ r.7 ;- L> o t- 0 - C: rr3 z- cr \3 :- (1;\ a 7 C\I r.-> 4- ~i \ ,+ ~3 L> Li\ Ln ti-) U> O L 3 O a 0 Cl \S b 1- b 1- t-- t- b t- i3 iU L'U ij - - - t- (PJ <Ti (-L OJ C'J PJ i\l 0 ~ 0 o O O O O O ~ O O G O O O O C 0 i 3 c C O G ~ c ; ' ~ - - - - - ~ - ~ - - - ~ - - ? - - - C 7 T - - - ' r - - - - C - - - t - - C - t - r i - C C ? - t - - - - - - - -

T a b l e 1 (cont . ) -7-

Table 1 (cont .) -8-

67 I O R U ? O ; ) W Q ~ - - \ ~ O ~ ~ L T L U > L T ~ O O M ~ ~ ~ C c D O 0 3 M o 3 O O O C O G ~ ~ ~ O L n O ~ I A ~ O 4 l - C b - C \ J Y O O t i n M P i Ln CC - v C \ L ~ C U ~ ~ C U N W I - C ~ - M O 3 W

I - -7 -F - C U C U - C U C F -

I I I

3 I - & C 4 , - m c . < ? - c c c , - u i C V V v v

I I I I

~2 I - ~ r u r u ~ a ~ m ~ = r c d - 4 I . . . . . . . . . . . .

I 0 0 0 0 0 0 0 0 0 0 0 0 I I I

c I ~ ~ ! ~ = F G U ~ C C Q ~ ~ ; C ~ ~ O ~ ~ C C I ~ M - L ~ ~ ~ ~ ~ ~ \ O ~ M ~ ~ O W ~ - - O ~ ~ ~ ~ ~ L ~ ~ N I J O C . \ O U ; I L ~ ~ ~ = ~ ~ ~ \ ~ ~ ~ O \ ~ C U ~ O ~ L C ~ ~ ~ U \ = ~ L ~ \ C ~ ~ - - C U \ C O \ ~ T I \ O C ~ \ D ~ U T ) L " ~

I v - - 7 - 7

I I I 1 - ~ ~ o ~ m ~ ~ c c ~ + c ~ ~ c m m ~ ~ o - - u ~ ~ ~ ~ m ~ c n m = f r n u ~ m w c \ : - c r - ~ o

a1 y e 7 F - C d M - -= i -zN-P) - ? F T - C U L ~ J - c.- 7 - 7

I I I I

3 1 c S O M M C \ U 7 U \ C C ~ M + G C 3 G \ M C O F C r 3 L n C - G ~ M c f , \ C ' 3 W ( C O ~ Z i Z M M i 3 \ O L n U 1 C~n,,- , ,?-M-s j - L n , - - C ' ~ - C I r l - ~ - m N - - N F - - m M m C \ I : ~ J C d - - - -

I 1 1 I I I 1 U ~ O M ~ : ~ ~ < V - ~ ~ ~ ~ - P - - - C ~ ~ Q C C ~ F U \ ' : ~ ~ M O ' \ ~ M & N ~ ~ J ~ ~ F C I - ~ ~ ' ~ ~ P ~ J

h 1 C\: J - - - - P - I 3 J C \ 1 Z : V J - C \ 1 L ? Y = ; C n 3 ? ; ~ C U ~ ' l C\JL- I

w 1 ~ J C ~ . ~ ~ O ~ ~ ~ ~ ~ - - ~ G Q O J ~ ~ ~ C ) C ~ ) C ~ L ~ , C - Q ~ C \ ~ - ~ ~ ~ C U L ~ ~ ~ ~ L ~ L ~ ~ ~ J M C ~ ~ - L ~ L ~ L ~ c3 1 C d ~ N ~ C \ ; C d N C U C . i \ ! ~ C \ I N C \ j - - N i \ ! - W ~ C U ~ d ~ ~ - - ~ ~ - - - - - - - - ~ - d ~ c U c U r: I 0 1 r--kFb++t--++FFFFFFFFF+FFFP--Fb+bFFFFFr--Fr--FbFF d l J Z J J 3 J S J I < J 3 3 5 3 T J 5 a = f 3 3 J 3 S = 3 T V = r J J J Z G 3 J 3 3

/ ~ ~ ~ ~ Y - ~ ~ - - ~ ~ - - - ? - C - C - - - - - - - ~ Y ~ - - c C - ~ - ~ -

I I i I I c ~ \ - r ~ \ ~ ~ ~ O C ~ ~ ~ ~ ~ ~ r \ ! C 3 O ( C C Y , L i 7 3 ' ~ ( 5 \ J ~ i ( ~ \ O ~ ~ W ~ \ C I 1 L ? C 3 N C ~ ; L ? ~ 3 C J - + - 1 1-7 C: NI r, 7 L;7 U'\ 3 (--'I C\I T- Cii C d Cs-) 3 C C W - r/7 - =1- - U7 3 1x 3 t i - \ L!l L? U\ CT: J C.7 - -7 - I - I G- d-, L-, ~3 Q a u-t x) in N <\ x - G CI ~ 8 3 in 3 - - M UT L- ~3 a- s- =r ( ~ 7 I-,- L.O v-1 r~ L- CQ - - - I

m I C\ ;*\ L1 ir, L1 LT\ L ~ I U'\ Ln U'I 23 U3 ilYi Li3 <\ L') L? U\ L'i LC\ U I I3 ii' \ G i Lf\ C\ L l i ~ ' i tI\ C: L? ~ i - : 2 ) in lY\ U> C> f %.D a a 1 2 c: :.D a a a a \3 iS. QT; -c 5 3 a <) e \3 c V: a a a a c '.r 0 iq Is

I 1 1 1

0 I

4 ' 2. 1 . .-., \; :- C ; C; 7 I?.) Ct'> -7 SI C? Lf SI 2-' L ~ I 0 F- LC: 'G2 C \ CI i;\ rC. - C\' W'l 3 CZ F <3 <S\ O r C d M C- CC) .s , - ,. - . . 1 \ ~ : ; L ~ ~ ~ L , ~ ~ D ~ C ' ~ U \ O \ C ~ O C C O J ~ U I U ~ I U ~ \ L ~ I ~ Q ~ - - O ~ O G C I C , O O - ~ - F U ' I L : \ Q

id I ( ~ ~ ~ ~ 7 M i ? ~ l p ~ C I ? P ~ l - C ) M ( Y l ~ J - J - - f 3 Z ~ J ~ ~ ; i - 3 L ~ - I ' \ ~ U 3 ~ ~ Q Q ~ ~ ~ C \ ~ : \ O ~ 3 ~ O ~ 3 ( , ; I , , ~ ~ - - r ~ - ~ - ~ ~ c ~ c - ~ - ~ ~ ~ - 7 - ~ ~ - ~ ~ ~ ~ - r - ~ ~ - -

Table 1 (cant.) -9-

Table (cont . )

,------,-- v v v v v v

O C G C O C V V V

Table 2 -11-

ant L C I ~ L ~ , ~ mcno c mr-t--rn,t oo c a 2 oo,o t--il-~u~ t--a C ~ M O ~ W O m f.7 L? p- C*? U^I Ln L9 W C\l - - C%J - y 7 - . - - C C F 7 ~ - v O j P , j C d

I - -. i - - i

I i G I V I

I G-i I z L1: I ..... cT1 I 4 I a I CG I H I 4 a I L4 02 l

i I 1 I

or-r-r-+r-t--r-a m m m m m m c n a \ c n w OCG w r ~ ~ m ~ \ c 3 ~ 3 ~ 1 ) t - - t - - r - ~ - c - + ~ ~ r - + a il7 L1 Ln U7 L? U7 U-l Ln Lrl U-l Ll3 Ln L? Ll7 U7 Ln b-l L n L n u\ L7 I1-I a> U7 L-1 In L? Lrl L7 Ln In In In Ln Ln m Ln u\ Li\

.- I l a u I -:a r( I Lr j 2 I

L i E-H (5 1 U l u 6 3 I

Table 2 (con t . )

N M m w - F - . . . . . . . O O O O O O G

T a b l e 2 (cont .)

STRCiIl-I SED IllEI'slT SAI'IPLES (11.1 PPI.')

Sample L a t ( 1:) Long (\; 1 Cu Pb Zn Au Ag I4 o Sb Sn !, ; l ! g PI s -----------------------------------------------------------------------------------------.-.---------

Table 2 (cont

.? i i n - v ~ ~ ~ r n v - a ~ r - - ~ \ 1 - - - - - - - - 3 - - - - - - ~ 7 C,m - m - C C 1 i v v v L' v v v v v v v v v v v v v rr, v

i I

- m C m . - - . - - v - F -- - - - - - , - . - - - M F . - T F v - - r c - 7 -

. o o . O . - 0 0 0 0 0 0 9 0 0 * 0 0 0 0 c 0 0 . . 0 0 - 0 0 0 . .o . a 0 0 - 0 . . . . a . . a = . . . . . . , 0 0 0 . . 0 . .

0 0 C * 7 0 V V V O O V 0 0 O O V O O V V O O O G O O O V V V 0 0 V O O v v V v v v v v v v v v v v v v v v V v

Table 3 -17-

~~a~~~~~maoanaaa a a a a ---e-,,, & r n Z r n Z Z z Z Z Z Z Z Z Z zs

- ~Y)cc)Q3mm,---Ln,-cUN 3.- O v - V V V V V N =r - -VVVPJ v - - - s - - r - - 0 NITJ Y 7 ? CU . . . . . . . . 0 0 0 0 CU 0 8 0 0 0 0 V v v v V V V

P?FFP C 3 , - P c Q ~ P ? C , - . - P - - m.- . . . . . . . . . . . . . . . . . 0 . 0 0 0 0 0 0 0 o o o o r - 0 0 0 0 0 0 0 - 0 . . v v v v v v V V V V V V V V o v 0 0

v v

Table 3 (cont . )

- - 7 v - - , - , - - - . - v - - - F - F r - - - . - . - - , - - v - v r - - - I ' V V V V V V V M V V V V V V V V V V V V V V V V V V V V

Y C Y F - F F v - - - r - r - . . . . . . . . . . . . . 0 0 0 0 0 0 0 0 0 0 0 0 0 V V V V V V V V V V V V V

- - O G G . ~ O O O O O O O O O 0 O O O O ~ O O ' C O O O . . a 0 0 V V - 0 0 0 V V V V V V V V V v V L ' V v v v L ' v \ ' v V O o v V V

V v v V

0 . ~ ~,2 c.; ~3 -: i cd i;7 CL b- r') c', L-> k - . j U L? zr i\i (-'J , r- 1.3 i 2 c. 1 \Li GT i-\ L'I c., i; .C=. L , : ' ) ( 7 i . .-- i - ' 8~3 ~3 ~ 1 0 C'. ;--W 1j3 C;\ C-\ CXJ C.: P7 rv.1 C\ 2\ C3 .;I+ ;- - c 7 1-43 J 7 - C,: i\l c :''A ( \! . :-; ( .: c L- ;r j. - 7 c\ C'i 5\ G? C;\ C C C 13 C C 7 7 Z\: Cd C ' 1 IP3 S ,' -7 =r LC, L I i ' r W < LC, L,7 T- \ 3 \:; k.r; O ~3

T - 7 C - T - Y F T - C 77 - C - 7 - 7- - - C ' ? < ' > I ' > ( ' - I r . : i ' l l

Table 4 -19-

ROCK SAMPLES IN BPM (unless spec i f ied otherwise)

LIVENCOOD ( A - 1 ) Q U A D R A R C L E ND=not determined

ROCK SAMPLES IN PPM ( u n l e s s o t h e r w i s e s p e c i f i e d )

S a m p l e L a t ( N ) Long(W) C u ........................................ r

LIVENGOOD ( A - 1 ) QUADRANGLE N D = n o t d e t e r m i n e d

R O C K SkRPLES I N PPM ( u n l e s s o t h e r w i s e s p e c i f i e d )

L I V E N G O O D (A-1) Q U A D R A N G L E ND=not d e t e r m i n e d

Sample L z t ( N ) Long(W) Cu Pb Zn Au Pa g Mo Sb Sn H&% i.J A s ...................................................................................................

R O C K SAMPLES IN PPN ( u n l e s s o t h e r w i s e s p e c i f i e d )

LIVENGOOD (A-1 ) Q U P - D R A N G L E ND=not d e t e r m i n e d

Sample L a t ( N ) L o n g ( W ) Cu Pb Z n Au Ag Mo S b Sn tl g liJ As ...................................................................................................

R O C K SAMPLES I N PPP ( u n l e s s s p e c i f i e d o t h e r w i s e )

F A I R B A N K S (D-1) Q U A D R A N G L E ND=not d e t e r m i n e d

< O . 1 5 ND 3 10 10 c . 1 . < I 9 ND 3 5 6 C.1 2 15 ND 2 15 5 < . 1 2 26 )ID 4 5 10 <.. 1 3 18 N D 2 5 5 < .1 4 2 1 N D 2 5 4 < . 1 2 1 9 1.1 D 2 5 5 < . 1 3 1 8 IJ D 3 5 5

- 1 3 39 ND 3 5 5 . 2 2 16 N D 55 5 10

< .1 3 2 1 ND 2 5 8 .2 7 29 31 450 5 5

< O . 1 3 2 N D 0 . 3 6 2 10 0 .1 3 2 N D

(0 .1 6 345 1 < o . 1 4

0 . 3 5 N D 3 5 > l o 0 0 < . I 6 PID 2 5 52 9 . 4 20 r1 D 3 5 55 0 . 3 3 N D 2 5 15

N D 2 15 95 2 5 2

< . 1 2 N j 7 D 2 5 23 < .1 3 N D 2 5 6 < . 1 8 PI D 2 5 2 0.1 6 PI D 2 5 5 0 .1 15 3 20 6 < . I 18 3 5 12 C . 1 13 3 5 5 0.1 4 ND 2 5 !ID <. 1 2 N D 2 5 ND < . I 3 N D 2 5 3 C.1 6 PID 165 5 6 < .1 1 N D 3 5 N D < . 1 24 N D 2 5 2

ROCK SAMPLES I N PPM ( u n l e s s o t h e r w i s e s p e c i f i e d )

FAIRBANKS (D-1 ) QUADRANGLE ND=not d e t e r m i n e d

S a m p l e L a t ( N ) Long(In1) C u Pb Zn A u Ag Mo Sb S n Hi2 GJ A s ...................................................................................................

R O C K SAMPLES I N PPM ( u n l e s s o t h e r w i s e s p e c i f i e d )

F A I R B A N K S (D-1 ) Q U A D R A N G L E ND=not d e t e r m i n e d

Sample L a t ( t 0 Long(W) Cu Pb Zn Au k g Mo Sb Sn El g kl As ...................................................................................................

STATE OF ALASKA

DEPARTMENT OF NATURAL RESOURCES

DIVISION OF GEOLOGICAL AND GEOPHYSICAL SURVEYS

Esther Wunnicke - Commissioner

Ross G, Schaff - State Geologist

January 1983

This is a preliminary publication of the Alaska Division of Geological and Geophysical Surveys and has not received f i i editing and review. The author will appreciate candid comments on the accuracy of the data and will welcome suggestions t o improve the report.

ADDENDUM TO Alaska Open-fie Report 164

GEOCHEMICAL RECONNAISSANCE OF THE NORTHERN FAIRBANKS D-1 AND SOUTHERN LIVENGOOD A-1

QUADRANGLES, ALASKA; SUMMARY OF DATA ON STREAM-SEDIMENT, PAN-CONCENTRATE,

AND ROCK SAMPLES

BY M.D. Albanese

Table 7. Rock descriptions for geochemical samples in the Livengood A-1 Quadrangle, Al-aska.

Sample Sample number typea Rock description (samples correspond to geochemical analyses in table 5)

Soil sample in white mica schist and quartzite Graphitic schist Graphitic schist in micaceous quartzite Shear zone Quartzite and feldspathic quartzite Coarse-grained grit Banded quartzite or calc-schist Quartz-muscovite schist Muscovite-chlorite schist with pegmatitic feldspar-chlorite dike Coarse-grained marble 2'-4'-wide white felsic dike Iron-stained quartz breccia Limonitic quartz vein in chlorite-muscovite schist Fine-grained amphibolite Bull quartz Quartz vein in biotite-muscovite-quartz schist 8'-wide quartz vein in biotite-muscovite-quartz schist Intrusive rock Tensional fracture filled with 2" quartz vein Graphitic schist with iron stain Clay gouge, iron-stained schist, and quartz fragments 6-9'' mineralized quartz vein Quartz-rich zone, iron-stained schist, and mylonite Crosscutting quartz vein Scorodite-stained quartz vein Sheared schist and quartz Hanging wall, quartz vein Sheared quartz or quartzite layer

a cc - chip channel (channel length denoted) cs - continuous channel sample gb - grab sample rc - composite or random chip

Sample number

Sample typea Rock description (samples correspond to geochemical analyses in table 5)

Calcareous amphlbolite with gossan layers Calcareous amphibolite with gossan layers Quartz-feldspathic-muscovite schist Quartz-feldspathic-muscovite schist Limonitic quartz vein Quartz pod with gossan and open space fillings Quartz-feldspathic schist Highly iron-stained dolomitic graphitic schist Limonitic quartz schist interbedded with amphibolite and quartzite Banded calcareous rock with quartz veinlets Altered quartz diorite with quartz-carbonate veins White quartz schist with stockwork veining Quartz-muscovite schist Quartz-muscovite schist Felsic white schist Veinlets in amphibolite Iron-stained felsic schist Quartz schist and felsic schist Felsic schist and quartz-muscovite schist White schist Altered granodiorite Quartz vein and stained feldspathic schist Quartz vein Graphitic schist Iron-stained quartz vein Quartz-muscovite-amphibolite schist with sulfides Felsite lens Felsite lens Iron-stained white quartzite and white muscovite quartz schist White felsic rock Light-grey quartzite with pyrite Intermediate intrusive: quartz monzonite-granodiorite Intermediate intrusive: quartz monzonite-granodiorite Intermediate intrusive: quartz monzonite-granodiorite Quartz-monzonite contact zone Intermediate intrusive: quartz monzonjte granodiorite

Sample number

Sample typea Rock description (samples correspond to geochemical analyses in table 5)

Quartz-monzonite contact zone Quartz-monzonite contact zone White schist and quartz-mica schist bJhite schist and siliceous quartzites White schist and quartz-mica schist Quartz-mica schist Quartz-mica schist and quartzite White schist Green schist Green schist Chlorite-quartz-mica schist, quartzite, and white schist Green schist with coarse garnet Micaceous calc-silicate marble and greenschist White schist Shear zone in quartzite and quartz-mica schist Quartzite and white schist with chalcopyrite, pyrite, and arsenopyrite White schist Strongly limonitic white schlst Limonitic felsic schist and quartz schist Limonitic white schist White mica schist and quartzite Garnetiferous quartzite with pyrrotite, chlorite, and muscovite Limonitic muscovite-schist seam Bleached garnetiferous muscovite schist with abundant limonite Banded greenstone Banded calc-silicate greenstone Banded calc-silicate greenstone Limonitic white schist Limonitic brecciated quartz and greenschist Altered limonitic nonfoliated rock White schist Banded greenstone White schist Micaceous greenschist Rusty white schist Laminated greenstone

Sample Sample numb e r typea Rock description (samples correspond to geochemical analyses in table 5)

Rusty white schist with quartz veins Rusty white schist with quartz veins Rusty white schist with quartz veins White schist and quartz-mica schist Actinolite schist White schist White schist with quartz veins White schist and white quartzite White schist and white quartzite White schist White schist and quartz Siliceous rusty breccia Feldspathic quartzite

Table 8. Rock descriptions for geochemical samples in the Fairbanks D-1 Quadrangle, Alaska.

Sample Sample number typea Rock description (samples correspond to geochemical analyses in table 6)

Biotite-rich siliceous rock Medium- to coarse-grained biotite quartz monzonite Coarse-grained porphyritic biotite granite Medium- to coarse-grained quartz monzonite Porphyritic quartz monzonite Porphyriti-c biotite granite Porphyritic biotite granite Medium- to coarse-grained porphyritic granite Iron-stained bjotite schist Medium- to coarse-grained biotite quartz monzonite Calc-amphibolite

a cc - chip channel (channel length denoted) cs - continuous channel sample gb - grah sample rc - composite or random chip

+I i $ Sample

number Sample typea Rock description (samples correspond to geochemical analyses in table 6)

Porphyritic quartz monzonite Quartz breccia Intrusive breccia with pyrite Biotite hornfels Calc-amphibolite Altered quartz-rich rock (hornfels?) Feldspathic schist Altered limonitic quartzite Quartz-filled breccia Coarse-grained granite Calcareous amphibolite Altered quartz-rich granite Porphyritic felsic intrusive Feldspathic biotite schist White mica-biotite-quartz schist Calc-amphibolite, marble, greenschist, muscovite schist Amphibolite, hornfels, feldspathic biotite schist Calc-amphibolite and hornfels Quartzo-feldspathic biotite schist Limonitic quartz boulder Hornfels in quartz-monzonite-dike contact zone Hornfels and calc-amphibolite Quartz boulders Limonitic amphibolite, coarse-grained marble, hornfels Amphibolitic calc-schist Felsic schist and calc-amphibolite Limonitic muscovite schist, locally brecciated Strongly limonitic vuggy quartz and limonitic schist with visible pyrite Strongly limonjtic vuggy quartz and limonitic schjst with visible pyrite Calc-schist Silicified quartzite Bull quartz with limonite staining Brecciated rock Porphyritic quartz monzonite Porphyritic quartz monzonite Porphyritic granodiorite

a U *d C (d k W)

k m aJ c

u a, a a a a a a~ a a a a a a a a a ~ a ~ a a a a a a U U u u u c U U U U U U U U U U U U U U U U U U m .r( . r l r l - r ( o -4 .I+ .~.rl.rlrlrl.rlrl.rl -4 .d .,-id rl.rl.rlri

a J G C C N c c c c c c c c c c c c c c c c c c G O U O O O a a 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 O N d N N N U U U N N N N N N N N N N N N N N N N N U C N C C C U

0 U O O O ( 6 k k O 0 0 0 0 0 0 0 0 k E Z E E E Z : .: .d rd a , ~ ~ N N N O ~ a a~ N N N N N N N N N N N N N N N N N C U C U U U U N 0 O U U U U U U U U U U U U U U U U U U

h a b L l b u c C b k h L l L l b L l L l b b b L l b L l L l L l k L l w a u ~ r d m m a u m m a a c e r d r o m m m m m a m m m c a r d 2 2 m 3 . d C 3 7 3 d r d r b k b 3 3 3 3 1 3 1 3 3 3 3 3 3 1 3 1 . r l w ~ a w w w m 3 . r c ~ M U w w v v u w w w v v v c f w u G - Z -

w U % U z U U U U C U U U U U a U a U U U U U U U U a J U U a U U P ) U U U U m-d C m r l - d r l d ' u a + ? i ~ . r l ? i r l . r l r ? 2 d . r l d r l . r l . r l . d - d ~ r l r l d r l d ~ ~ d r l r l r l

u O . r l U U U a J a J k u + u u . d u . d u u u u u u u U . r l u u . d u U . d U u u u m + E C d . d . r l > . d n . r l m . r l r l m + a . d r l . d d r l . d . d . d a a d a d . r l m . d r l . r l . r l U b U U L l L l k b k h b b b L l L l M b & b h b L l b k h b b

h~ m h h h ~ . d rd h a h h a h a h h h h h h h h a , h h a h h a ~ h h h h E C U S C C U U U C ~ C C ~ C U C C C C C S C C ~ C C ~ C C U S C S C

a u h a a a b . r l . d a.rl a a . d a+ a a a a a a a a r l aa.rl a a . d a a a a c b m a b k k ( d d d L l d h b d L l d k L l L l b L l b L l b d L l & d b L l d L l b b b r d ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ a o o a o a o o o o o o o o a o o a o o a o o o o w & a G & & & W m m & 4 G & < G d & & & & & & & & 4 & & 4 & & 4 & & & &

Table 8 ( c o n t . ) - 6 -

Sample numb e r

Sample typea Rock description (samples correspond to geochemical analyses in table 6) --

Porphyritic quartz monzonite Porphyritic quartz monzonite Porphyritic quartz monzonite Aplite dike Porphyritic quartz monzonite Aplite dike Porphyritic quartz monzonite Porphyritic quartz monzonite Porphyritic quartz monzonite Aplite dike with sulfides Porphyritic quartz monzonite Porphyritic quartz monzonite Porphyritic quartz monzonite Porphyritic granodiorite Porphyritic quartz monzonite Porphyritic quartz monzonite Porphyritic quartz monzonite Porphyritic quartz monzonite Porphyritic quartz monzonite Porphyritic quartz monzonite Porphyritic quartz monzonite