DEPARTMENT OF THE INTERIOR
U.S. GEOLOGICAL SURVEY
Petrographic data for plutonic rocks and gneisses of the Glacier Peak Wilderness and vicinity, northern Cascades, Washington
by
Arthur B. Ford , James L. Drinkwater , and Steven L. Garwin*
Open File Report 85-432
This report is preliminary and has not been reviewed for conformity with U.S, Geological Survey editorial standards and strati graphic nomenclature. ^Menlo Park, California
1988 CONTENTS Page Introduction 1 Acknowledgements 5 Methods 5 Data summaries 9 Data reports (table no. in parenthesis) Mount Bucklndy pluton (l) 29 Cascade Pass pluton (2) 32 Cloudy Pass batholith (3) 35 South Cascade Glacier stock (4) 39 Railroad Creek pluton (5) 42 Duncan Hill pluton (6) 46 Clark Mountain stocks (7) 49 High Pass pluton (8) 51 Cyclone Lake pluton (9) 54 Downey Creek pluton (10) 57 Tonalite of Bench Lake (11) 60 Sulphur Mountain pluton (12) 63 Jordan Lakes pluton (13) 66 Sloan Creek plutons (14) 69 Tenpeak pluton (15) 72 Seven-fingered Jack and Entiat plutons (16) 77 .Hoiden Lake pluton (17) 80 Cardinal Peak pluton (18) 83 Mount ChavaT pluton (19) 86 Riddle Peaks pluton (20) 90 Marblemount Meta Quartz Diorite (21) 94 Dumbell Mountain plutons (22) 97 Magic Mountain Gneiss (23) 100 Leroy Creek pluton (24) 103 Eldorado Orthogneiss (25) 106 Skagit Gneiss (26) 109 Swakane Biotite Gneiss (27) 112 Miscellaneous small plutons (28) 116 Sitkum stock 117 White Chuck Glacier stock 117 Cool stock 117 Dead Duck pluton 117 Foam Creek stock 117 Downey Mountain stock 117 Grassy Point stock 118 Hidden Lake stock 118 Pear Lake pluton 118 References 119 ILLUSTRATIONS Figure Page 1. Index map 2 2. Geologic sketch map of region, showing unit symbols 4 3. Rock (mode) classification diagram 7 4. Index of topographic map quadrangles 8 5. Frequency of average rock types, by unit 10 6. Rock classification, averages of units 11 7. Occurrence of auxiliary minerals in units 12 8. Occurrence of biotite and hornblende in units 14 9. Specific gravity and mafic-mineral variation, by unit 15 10. SiOp and Na20+l<20 variation, by unit 18 11. Na20+K20, FeO*, and MgO variation, by unit 19 12. FeO*/MgO and Si02 variation, by unit 20 13. Plagioclase (CIPW) composition and A1203 variation, by unit 21 14. A1203, ^203, and KoO variation, by unit 22 15. Frequency of Al203/tCaO+^O+I^O), by unit 23 16. l<20 and Si02 variation, by unit 24 17. Chemical classification, CIPW ab, an, and or, by unit 25 18. Chemical classification (Streckeisen and Le Maitre, 1979) 26 19. Frequency of CIPW an percent, differentiation index, and Mg nos. 27 Geologic units of study: 20. Buckindy pluton, geologic sketch map 29 21. Buckindy pluton, modal vatiation 30 22. Cascade Pass pluton, geologic sketch map 32 23. Cascade Pass pluton, modal variation 33 24. Cloudy Pass batholith, geologic sketch map 35 25. Cloudy Pass batholith, modal variation 36 26. South Cascade Glacier stock, geologic sketch map 39 27. South Cascade Glacier stock, modal variation 40 28. Railroad Creek pluton, geologic sketch map 42 29. Railroad Creek pluton, modal variation 43 30. Duncan Hill pluton, geologic sketch map 46 31. Duncan Hill pluton, modal variation 47 32. Clark Mountain stocks, modal variation 49 33. High Pass pluton, geologic sketch map 51 34. High Pass pluton, modal variation 52 35. Cyclone Lake pluton, geologic sketch map 54 36. Cyclone Lake pluton, modal variation 55 37. Downey Creek pluton, geologic sketch map 57 38. Downey Creek pluton, modal variation 58 39. Tonalite of Bench Lake, geologic sketch map 60 40. Tonalite of Bench Lake, modal variation 61 Figure Page 41. Sulphur Mountain pluton, geologic sketch map 63 42. Sulphur Mountain pluton, modal variation 64 43. Jordan Lakes pluton, geologic sketch map 66 44. Jordan Lakes pluton, modal variation 67 45. Sloan Creek plutons, geologic sketch map 69 46. Sloan Creek plutons, modal variation 70 47. Tenpeak pluton, geologic sketch map 72 48. Tenpeak pluton, western area, modal variation 73 49. Tenpeak pluton, eastern area, modal variation 75 50. Seven-fingered Jack and Entiat plutons, geologic sketch map 77 51. Seven-fingered Jack and Entiat plutons, modal variations 78 52. Holden Lake pluton, geologic sketch map 80 53. Holden Lake pluton, modal variation 81 54. Cardinal Peak pluton, geologic sketch map 83 55. Cardinal Peak pluton, modal variation 84 56. Mount Chaval pluton, geologic sketch map 86 57. Mount Chaval pluton, modal variation 87 58. Riddle Peaks pluton, geologic sketch map 90 59. Riddle Peaks pluton, modal variation 91 60. Marblemount Meta Quartz Diorite, geologic sketch map 94 61. Marblemount Meta Quartz Diorite, modal variation 95 62. Dumbell Mountain plutons, geologic sketch map 97 63. Dumbell Mountain plutons, modal variation 98 64. Magic Mountain Gneiss, geologic sketch map 100 65. Magic Mountain Gneiss, modal variation 101 66. Leroy Creek pluton, geologic sketch map 103 67. Leroy Creek pluton, modal variation 104 68. Eldorado Orthogneiss, geologic sketch map 106 69. Eldorado Orthogneiss, modal variation 107 70. Skagit Gneiss, geologic sketch map 109 71. Skagit Gneiss, modal variation 110 72. Swakane Biotite Gneiss, geologic sketch map 112 73. Swakane Biotite Gneiss, modal variation 113 74. Miscellaneous small plutons, modal variation 116
m INTRODUCTION
This preliminary report contains petrographic data (modes, specific gravities, and rock classifications) for plutonic and gneiss units of the Glacier Peak Wilderness and vicinity, northern Cascades, Washington (fig. 1). The study area straddles the drainage divide of the range immediately south of North Cascades National Park Complex. Data are given for a total of 639 samples from 36 plutons and gneiss units of this area which transects a large south-central part of the crystalline rock province of the North Cascades. The sampling and related fieldwork were carried out in summers of 1980-82 as part of the U.S. Geological Survey's study of the mineral-resource potential of the wilderness and proposed additions to the wilderness (Church and others, 1984). The purpose of this report is to provide background reference data for other reports and geologic, geophysical, and geochemical maps of the area that are in various stages of preparation.
Locations of units sampled in this study are shown (capitalized symbols) on the geologic sketch map of figure 2. The tables of data for most units are accompanied by larger scale geologic sketch maps that were prepared from a 1:100,000-scale geologic map of the wilderness (Ford, unpublished data) or other sources as indicated. A complete discussion of the geology of the area and of individual units is beyond the scope of this report, which therefore does not reference the abundant previous work by others on most units. Principal references for individual areas of prior geologic mapping are shown on an index map of Ford (1983a, fig. 2).
The regional geologic setting of the area and description of units as they occur in areas to the north are given by Misch (1966). Studies by many (here uncited) earlier workers show that this part of the North Cascades is an area of great lithologic variety, structural complexity, and lengthy igneous activity. The record of igneous activity ranges from at least Triassic (Marblemount Meta Quartz Diorite and Dumbell Mountain plutons) to the Quaternary (Glacier Peak volcano). Depending on interpretation of its protolith, the Swakane Biotite Gneiss may indicate a record back to the Precambrian (Mattinson, 1972). Major episodes of plutonism occurred in the Late Cretaceous (Eldorado Orthogneiss and Sloan Creek, Tenpeak, Seven-fingered Jack, Entiat, and possibly Sulphur Mountain, Jordan Lakes, Mt. Chaval, and Riddle Peaks plutons, among others); the Eocene (Railroad Creek and Duncan Hill plutons, among others); and the Miocene (Cloudy Pass batholith and tjt. Biickindy and Cascade Pass plutons, among others). The Cretaceous and older plutons are generally well foliated and recrystallized, indicating emplacement before or during regional metamorphism. Major regional synkinematic metamorphism of 90- 60 Ma age (Mattinson, 1972) formed extensive units of gneiss, migmatite, and schist (Chiwaukum Schist and schists of the Cascade and Napeequa Rivers) in the area; metamorphic facies vary from greenschist or locally subgreenschist to amphibolite (garnet, staurolite, kyanite, and sillimanite zones). Eocene plutons are in places foliated or show zones of cataclasis but are little recrystallized. Miocene plutons are shallow-level intrusions characterized by porphyry phases, dike complexes and roof-breccia complexes in places containing breccia pipes. They also contain areas of hydrothermal alteration and porphyry copper-molybdenum mineralization.
Data on the oxygen isotopic composition of many samples of the present report are given by White and others (1985). Magnetic susceptibility data for samples are given by Ford and others (1986). Results of geophysical studies of the area include a Bouguer gravity anomaly map (Sherrard and Flanigan (1983) an aeromagnetic map (Flanigan and Sherrard, 1985) and a geologic interpretation of the aeromagnetic map (Flanigan and others, 1983.
I22°00' I2I°00'
- 48®30'
- 48°00f
Figure 1. Index map showing location of the Glacier Peak Wilderness study area (unshaded) and principal access routes. Areas A, C, D, and G are proposed wilderness additions (see Church and others, 1984). Figure 2. (facing page)--Sketch geologic map of the Glacier Peak Wilderness (unshaded) and vicinity showing generalized map units and major faults. Names of units from original sources given in Ford (1983a) or from Ford and others (in press). TE includes area (TEw) mapped as White Mountain pluton by Cater and Crowder (1967). Unit abbreviations used in this report are as follows: BE Tonalite of Bench Lake 00 Jordan Lakes pluton BU Mount Buckindy pluton LC Leroy Creek pi uton CA Cascade Pass pluton MA Marblemount Meta Quartz Diorite CD Cardinal Peak pluton MM Magic Mountain Gneiss CG South Cascade Glacier stock PL Pear Lake pluton CH Mount Chaval pluton RC Railroad Creek pluton CM Clark Mountain stocks RP Riddle Peaks pluton CO Cool stock SI Sitkum stock CP Cloudy Pass batholith SF Seven-fingered Jack plutons CY Cyclone Lake pluton SG Skagit Gneiss DD Dead Duck pluton SL Sloan Creek plutons DH Duncan Hill pluton SU Sulphur Mountain pluton DM Downey Mountain stock SW Swakane Biotite Gneiss DO Downey Creek pluton TE Tenpeak pluton DU Dumbell Mountain plutons WG White Chuck Glacier pluton EG Eldorado Orthogneiss gns gneiss and schist, mixed FO Foam Creek stock gs greenschist and blueschist HI Hidden Lake stock vie volcanic materials HO Hoi den Lake pluton HP High Pass pluton GR Grassy Point stock I2O°45' 48°30'
APPROXIMATE BOUNDARY OF GLACIER PEAK WILDERNESS
-4e°l5'
-48°00 ACKNOWLEDGMENTS
We appreciate much aid in sampling and other fieldwork by the following participants in the 1980-82 field study of the Glacier Peak Wilderness: W. H. Nelson, R. A. Loney, R. A. Sonnevil, the late Carl Huie, R. A. Haugerud, and T. A. Spreiter. Many of Carl Huie's samples for his unfinished thesis (Univ. Montana) on the Riddle Peaks pluton were used in our study of that body. We thank Peter Misch (Univ. Washington, Seattle) for providing samples from his work on the Marblemount Meta Quartz Diorite of its type area near the town of Marblemount, for comparisons with this area. We particularly thank helicopter pilots Anthony Reece (Darrington, Wash.) and Gary Lott (San Jose, Calif.) for flying skills that made sampling possible in this area of exceptionally rugged alpine terrain and generally inclement weather (during our periods of fieldwork).
METHODS
Most samples are medium to coarse in grain size, and therefore (volume) percentages of quartz, K-feldspar, plagioclase, and total mafic minerals were determined by the stained-slab method of Norman (1974). Except for a few samples counted only in thin section, modes were determined by counting approximately 1,000 points on rock slabs of generally about 70 cm or greater area that were etched (HF acid) and stained for K-feldspar (yellow) and plagioclase (red). Results are given in following tables and shown diagrammatically on triangular plots of (1) K-feldspar, quartz, and plagioclase (recalculated to 100 percent) used for modal classification; and (2) quartz, total mafic minerals, and total feldspar. The plots of modal data show areas (shaded) of two standard deviations of the data, based on (+ and -) one standard deviation from the mean (small triangles) for each end member. In the quartz-mafics-feldspars plots (2), samples lying inside the area of standard deviation are not plotted.
Many of the samples were also used for other studies, including major- and minor-element chemistry, geochronology, oxygen and strontium isotopic analysis, and magnetic susceptibility determinations. Most of those samples were additionally point counted in thin section to determine amounts of individual mafic and other minerals, such as pyroxene, biotite, hornblende, epidote, and muscovite. Primary and secondary minerals were not discriminated in the thin-section mode counts. All green and brown amphiboles were counted as "hornblende," a term which for some units, such as the Riddle Peaks and Chaval plutons and the Marblemount Meta Quartz Diorite, includes a variety of primary and secondary amphiboles. "Epidote" includes all minerals of the epidote group, except for allanite, an accessory mineral reported separately. All white micas are included under "muscovite." The stained-slab modes were recalculated using the thin section data. All results are plotted in the modal classification diagrams of units to show the complete variation of our determinations, but sample plot numbers are given only for chemically analyzed samples.
Specific gravity was measured with a direct-reading beam balance, by first balancing a sample of generally fist size or larger dry in air and then rebalancing in water after a sufficient immersion period to allow all possible escape of air bubbles from cracks and surfaces. The method commonly yields results somewhat less than by other methods probably due to presence of air remaining in deep interior cracks or pockets.
In this report most plutonic rocks are named using the classification and nomenclature of Streckeisen (1967), based on modal proportions of quartz, K-feldspar, and plagioclase (fig. 3). Figure 3 is also used to indicate compositional varieties of rocks not included in Streckeisen's (1967) diagram, such as alas kite (<5 percent mafic minerals) and gneiss that may be nonmagmatic (Swakane Biotite Gneiss) or magmatic (Dumbell Mountain plutons) in origin. Rocks in the plagioclase corner of the diagram require knowledge of plagioclase composition for naming. Plagioclase An contents have not been determined by optical or other methods in this preliminary study, and we therefore use CIPW normative plagioclase compositions determined from available chemical analyses to distinguish diorite or quartz diorite (An<50) from gabbro or quartz gabbro.
Locations of the units studied are shown in figure 2, on indexes accompanying geologic sketch maps of units, or are described using USGS quadrangle map names (fig. 4). Sample sites are shown on a 1:100,000-scale topographic map base (Ford, 1983b). Approximate locations of sites sampled for chemical as well as petrographic studies are shown on geologic sketch maps of the units. Quartz
-TON A LITE
QUARTZ DIORITE OR .QUARTZ GABBRO \5-DlORITE OR AlkaliZ___L MONZODIORITE\ A GABBRO feldspar I0 65 90 Plagioclase
Figure 3.--Modal classification of plutonic rocks based on (volume percent) proportion of quartz, plagioclase, and K-feldspar. Classification of Streckeisen (1967). I20°45' 48°30'
48°OCf
Figure 4.--Index to 1:24,000 and l:62,500-scale USGS topographic map quadrangles af the Glacier Peak Wilderness and vicinity. Dotted lines show proposed additions to the Wilderness.
1. Illabot Peaks 1966 13. Stehekin 1969 2. Snowking Mtn 1966 14. White Chuck Mtn 1966 3. Sonny Boy Lakes 1982 15. Pugh Mtn 1966 4. Cascade Pass 1963 16. Glacier Peak 1950 5. Goode Mtn 1963 17. Hoi den 1944 6. McGregor Mtn 1963 18. Lucerne 1944 7. Prairie Mtn 1966 19. Bedal 1966 8. Huckleberry Mtn 1982 20. Sloan Peak 1966 9. Downey Mtn 1963 21. Blanca Lake 1965 10* Dome Peak 1963 22. Bench Mark Mtn 1965 11. Agnes Mtn 1963 23. Poe Mtn 1965 12. Mt Lyall 1963 24. Wenatchee Lake 1965 DATA SUMMARIES
Average modal compositions of tonalite greatly predominate in the area and vary widely from granodiorite for two of the largest bodies (Cloudy Pass batholith and Railroad Creek pluton) to quartz gabbro and gabbro (figs. 5, 6). The averages are based only on our data, and much additional modal data for many units are available in reports listed by Ford (1983a). Some units extend beyond the study area where they may have different modal averages, such as the Duncan Hill pluton which is a tonalite in this area (fig. 6, DH) but mostly granodiorite where chiefly exposed to the south (Cater, 1982, p. 62). Many of the smaller bodies (Cool, White Chuck Glacier, Sitkum, Downey Mountain, and Hidden Lake stocks, among others) were probably not representa tively sampled due to sampling at only one or two sites generally selected on the basis of suitability for helicopter landings. For many units, our rock names differ from those given by others, probably owing to sampling of different areas as well as to usage of different classifications. The hornblende-"quartz-diorite" augen gneiss of the Dumbell Mountain plutons of Cater and Crowder (1967) and Cater (1982, p. 17), for example, is tonalite by our sampling and nomenclature (fig. 6, DUa).
Mineral occurrences of units are shown in figure 7. Garnet occurs only in plutons of dated or inferred pre-Tertiary age (fig. 7B), except for sparse occurrence in a contaminated contact zone of the Rail roa
Figure 5.--Frequency distribution of average rock types of pi utons and gneiss units of the Glacier Peak Wilderness area. Based on figure 6 and on chemical data on CIPW normative compositions of plagioclase (gabbroic rocks based on An>50). Symbols explained in figure 2 and text.
10 r \ TONALITEX* 'DO AVERAGE MODAL COMPOSITION OF |J PL* PLUTONS AND SU« MMs HP^ G"- CM GNEISS UNITS
R GRANODIORITE \ CA CR. \ *BE BU
EG,
pco
WG QUARTZ .DIORITE QUARTZ and MONZODIORITE QUARTZ GABBRO
GABBRO \L \L AZ_ ±L AZ V_ K-FELDSPAR 10 PLAGIOCLASE
Figure 6.--Average proportions of quartz, K-feldspar, and plagioclase in plutons and gneisses of the Glacier Peak Wilderness area. Plot shows plagioclase corner of figure 3. See tables for number of samples averaged for each unit. Symbols explained in figure 2 and text.
11 L j U J w 00 Cc a u
WG 1
A TERTIARY PLUTONS
Figure 7.--Occurrence of minerals in plutons and gneiss units of the Glacier Peak Wilderness area. Solid lines, minerals generally present (thin sections) in a significant amount; dashed lines, generally present in trace or other minor amount; dotted lines, generally minor, sporadic occurrence. "Muscovite" includes all white micas; "hornblende" includes all primary and secondary green and brown colored amphiboles; "epidote*" is coarse, well formed and possibly similar to "magmatic epidote" described by Zen and Hammarstrom (1984). Variable amounts of secondary chlorite, colorless amphiboles, epidote, and other minerals are also commonly present. /\, plutons of dated or inferred Tertiary age; B_ Kfollowing page), units of dated Cretaceous and older age and of undated age that may include early Tertiary. Symbols of units explained in figure 2.
12 r~ n H CO CO CO co CO 3) TJ 2 2 c_ I I I o m o o o o o o 00 m S c 1- o n TJ l- 2 > O O TJ O D O o c o £ < I o m
PLAGIOCLASE CD
1 TJ r- QUARTZ 0p D C rt H H- D O Z K-FELDSPAR fDs 0)
o Z MUSCOVITE ID o c o Z Z BIOTITE m Z 0) 0 0) HORNBLENDE c Z Z H PYROXENE o 0) m 0-n FE-TI OXIDES TJ ID m H GARNET m ID SPHENE ID EPIDOTE* frl
PERCENT MAFIC MINERALS _ ro -(^ o o o 1 I ' i i I / ' I _ ' ~n i * / " ~%c / O|T -3 n> . / -h » -j. « i* / ^ 3 3 00 0 / O l/i -% 1 T O QJ 1 / 3 *- -+» ;o / *o CT" ' t/l fD / ro . _.._.. Q, C7«/ 3 "-4 3 3 rf C Q. ^-1 CD -" ^ / n> . Q* -a o K ~" i ~" n 3 o QJ C 3 OO n r* O Q-*<
PERCENT MAFIC MINERALS
c _ ro CM -fr -hO -' CO o o o o -" -h 3 1 , | . | , | co vo C "T3 T -*. 1 fD 3 C 1
1\3 QJ O CO 1 3 J fVl ^^ g^i 3 -% d- CX fD tn CQ 3 Q r° ^^ t-f T Q- 3 a> fD fD o X «/> CQ O c* cn in cn O O fD £ "> C -* o«»°\ ? < \ni / o 2 n-cn 3-rr-o n> fD fD 0 5* *°-/8«/ Q- - 11 3JCD / / / CD -*> cr &4g «< cn o o fD fD T ro . 2i it%& -s cu T cn '->! O n- -o - 0) rD r^ *n ^1 Q* ^^^ ' \a # JD ?r rn . «, \ «o 3 g z 5. 2 g x v* i n- Ti fD ' 3- l/> Q. O *°'i V o s: x^ 3 T 0 _ fD 3 n- O r* fD cn Tl rr cn J CT O 01 ^ ^\ g Q- 0 < o\ ,=r cn o ^ T 3 H ° \ _ fD r^* ^^ C/) Oi fD \ m m << 3 3 n- ro - \ 00 O 0cn 0-h o 3- 3 fD o cn \ X Q. -h T3 -" *x 1 \ ' O O» -i. 0 \ - 33 a ro - \ « fD 3 O. - fD \ s Oi T \ 3 ' ' \ 3 fD \ \ \ ro \ to V 0 ^» 1,1,1.1. Very little chemical data on rocks of the area have been published, except chiefly for the southeastern part of the Cloudy Pass batholith in the Hoi den quadrangle (Cater, 1969, p. 28-30); plutons and stocks that are part of the batholith or presumably related to it in the Glacier Peak quadrangle (Tabor and Crowder, 1969, p. 14); and many of the plutons of the Hoi den and Lucerne quadrangles (Cater, 1982). Chemical analyses of rocks from most of the plutons and major units of gneiss have also been made as part of our study of the area. Preliminary compilations of our (XRF) major-element chemistry are shown in diagrams for comparison of the chemical characteristics with modal data of units. The chemical data are also used to compute CIPW normative plagioclase compositions on which the rock classification and nomenclature are in part based. The CIPW norms and other chemical data represented in diagrams are from analyses normalized on a volatile-free (H20, C02 ) basis.
The variation of Na 2 0 + KoO with SiCU contents shows subalkalic characteristics of all units (fig. 10). A variety of other plots of the chemical data show a distinctly calcalkalic nature of the suite. In an AFM diagram, possible tholeiitic characteristics are shown by only two gabbroic intrusions: the Hoi den Lake pluton of hornblende-quartz gabbro and the Riddle Peaks pluton of layered and no.nlayered (olivine-normative) hornblende gabbro (fig. 11; HO, RP). In an FeO /MgO and Si02 diagram, only the Riddle Peaks pluton shows tholeiitic characteristics, and the Hoi den Lake, Dead Duck, and Downey Creek plutons have iron-enriched compositions near the field of tholeiite and markedly apart from compositions of most units (fig. 12; RP, HO, DD, DO). Other chemical data suggest calcalkalic compositions of both the Holden Lake and Riddle Peaks plutons, in a diagram (fig. 13) showing CIPW- normative plagioclase compositions used for determining nomenclature of average rocks of the units. All units have molecular Alo03/(Na20 + K20) > 1, with none even closely approaching the field of peralkaline rocks (fig. 14). Approximately one half of the units are peraluminous (fig. 15), as defined chemically by a ratio (molecular proportions) Al 203 /(CaO + Na20 + K2 ) > 1 (Clarke, 1981, p. 3). Nearly one quarter of the units have average compositions lying within Gill's (1981, p. 6) field of medium-K, high silica orogenic andesite, but most have Si02 contents greater than the 53-63 percent range for andesite (fig. 16). Extrapolation of this field into more siliceous compositions suggests medium-K characteristics of most units, including all Tertiary plutons; a low-K nature of some pre-Tertiary units; and high-K nature of only the Eldorado Orthogneiss (fig. 16, EG).
Rock nomenclature based on modes (fig. 6) and chemical data (figs. 17-18) is similar for many units but there are» discrepancies for some. For example, the Sulphur Mountain and Jordan Lakes plutons are tonalite in mode (fig. 6, SU and JO) but are granodiorite near the field of tonalite in chemical composition (fig. 17). The modal classification does not discriminate trondhjemite, which some units would be classed on the basis of chemical composition (fig. 17). Rocks classed as quartz diorite or more mafic by mode are not discriminated in the chemical classification of figure 17.' Rock names given in this preliminary report are based on modes, supplemented by CIPW normative compositions of plagioclase (An = an x 100/(an + ab): in the modal classification of figure 3, units with an average plagioclase composition of Ap or 9 rea ter (fig. 13) are gabbro or quartz gabbro (fig. 6).
16 Chemical characteristics of igneous rocks are used in many studies (for example, Martin and Piwinskii, 1972; Miyashiro, 1975; Petro and others, 1979; and Gill, 1981) to discriminate compressional, or orogenic, from extensional, or anorogenic, tectonic settings of magmatism. Calcalkalic suites, such as that of the Glacier Peak Wilderness area (fig. 11) characterize orogenic belts of island arcs and active continental margins (Miyashiro, 1975, p. 257). AFM diagrams of rocks from such a setting are characterized by little scatter paralleling the F-M join and much scatter normal to the join (Petro and others, 1979, p. 224 and fig. 4), as in the Glacier Peak suite (fig. 11). Patterns of frequency distributions of normative plagioclase composition and of the differentiation index of the Glacier Peak suite (fig. 19, A-B) are like those typical of compressional suites and markedly different from those of extensional suites showing multimodal patterns (Martin and Piwinskii, 1972, p. 4968; Petro and others, 1979, p? 223). The Mg numbers, namely, the molecular ratio Mg x 100/(Mg + Fe ^), of many units (fig. 19, C) approximate an average value of 53 for orogenic andesite, a value considered too low to represent primary mantle melts that should have values of 67 or higher (Gill, 1981, p. 110). The Mg number depends in part on the oxidation state of iron: if recalculated so that Fe^/FeO = 0.2 (Hughes and Hussey, 1976), Mg values for only two units (fig. 19; CH, HO) would be nearly those of possible mantle characteristics.
The diagrams of figures 10 to 19 are given only to show chemical characteriza tions of the units. They imply neither genetic origins of units nor genetic relations between units. For example, the "calc-alkalic" trend of fig. 11 and "calc-alkalic" compositions of figs. 11-13 do not imply the commonly assumed presence of a differentiation sequence or even an igneous origin of all rocks, because the wide age range (Precambrian? to late Tertiary) of units argues against genetic relations and because some gneisses may be of sedimentary parentage.
17 DO'
EG
.SG BE »HI .HP.l UJ si. SU * Pn- «JO OR. WG. u .CP PL .CG Q. .SWt ^SW TE. SF. .»SL DM DD BUd «MA, .MMs o SI .DUo CM MA o RP (VI oo Z 3 HO
I 50 55 60 65 70 75 SI02 (WT. PERCENT)
Figure 10.--Variation between total alkalies and SiOp contents in plutons and gneiss units of the Glacier Peak Wilderness area. Dividing line between alkaline and subalkaline rocks from Irvine and Baragar (1971, p. 532). Symbols explained in figure 2 and text. FeO'
MgO
Figure 11.--AFM (A, Na 20 + K20; F, FeO ; M, MgO) diagram of average compo- sitjons of plutons and gneisses of the Glacie^ Peak Wilderness area FeO = FeO + .8998 * Fe 20o. Isopleths of FeO /MgO, for comparisons with figure 12, are from Gill (1981, p. 9); dashed line separating tholeiitic and calcalkalic fields from Irvine and Baragar (1971). Symbols explained in figure 2 and text.
19 o>
1.0 70 75
Si02 (WT. PERCENT)
Figure 12.--Variation between FeO*/MgO and SiO^ in plutons and gneiss units of the Glacier Peak Wilderness area. Line separates tholeiitic and calcalkalic compositions: solid line from Gill (1981, p. 10); dashed line, projection into field of higher SiOo contents. Symbols explained in figure 2 and text. IZ
UD tO fNJ C A a> oo O O* -« Q» -S | i | i | i | i | i | i 1 . 1 3 3 3 (D Q. Q. I Q. l-> ^f/f^ Cf - 3> U) rv/"^ n> Q) * />?/'** x tjoro i ->l /*»/!? cf "5 O 1 O ~~ -^/^ ~ 3°° £? O T 0 O - f^ -h 3 Q» /o o cf cf / i « fD -* " -1 3 O < cf 3 / 3 o cr ro -h ro cf o> 0 .._ Q» T3 Si 0 -o33 3 ro / a. c ro cf 3 -z. CO O 0* 3 3 O T t/» O / * o* -3 to su 3 SU 3 0* / S ^ -J Q. cf 1 *H- 3 ro < 01 GABBROIC COMPOSITIONS// " m o / S - J TJ ^J ^^ ^^ 13 / o ^ ? ' i~ / 0 > ^ Q. %H * t/) Q* CO ^^ "CJ C -* / ri ^S n G/ / ^ TT ^ - -3 nO ~ / O ^ ^Mf if tn cf o / c H n *o Ok) (/> Ql i~o en t/> *-^o ro > ^ g « -*> 0 cf 3 n 0 %0 « OO 3- *< fD n o 2 O 3 o 0 W 33 o ° ocr CD «-a 3 f "«to su o 13 £} a?** en w» n t/» o c O n ^ ro fD cf c/> X -I -* H ^« -o o J2 ~n CD -O 3 < o ^ n o SU fD -z. ^p 33 - at *~^ 3 TV 0* ^_^^ £ ro 3 *g gj T3 a. z: o 2 -«. x ^ c* 3 a. - 2* -*> -ifD oO - 3 -x. *5^X -^j tQ fD *-+ ra C W» Q» - 2 -1 U> 3 O fD 2 ro -i fD a* at cr O
1,1,1,1,1.1,1.1 PERALKALINE
NooO K20
Figure 14. Molecular proportions of A^C^, Na20, and 1^0 of pi utons and gneiss units of the Glacier Peak Wilderness area. Shows only units lying outside the field (shaded area) of one standard deviation (+ and -) from the mean (solid triangle). Symbols explained in figure 2 and text.
22 WG TEw SU TE SG I*Y lv> SL RC SI PL SF > MMs 0 z MAt LC UJ MA JO ID 10 o EG HP UJ o: DUh HI u_ DUo GR DH FO CP DO CO DM RP CM CY HO CA CG swt DO BUd CD SW CH BU BE MM OJB 1.0 1.2 MOL. AL203/(CAO+NA20+K20)
Figure 15.--Frequency distribution of the ratio (molecular proportions) Al 2 03/(CaO + Na 2 0 KoO) of plutons and gneiss units of the Glacier Peak Wilderness area. Symbols explained in figure 2 and text.
23 LJ O ui o.
o
Si02 (WT. PERCENT)
Figure 16.--Variation between average K20 and Si02 contents of piutons and gneiss units of the Glacier Peak Wilderness area. Andesite subfields and contours of andesite analyses from Gill (1981, p. 6). Boundaries of subfields extended (dashed lines) into area of Si02 content greater than andesite. Symbols explained in figure 2 and text.
24 an
eo or-
Figure 17.--Average proportions of CIPW normative ab, an, and or of plutons and gneisses of the Glacier Peak Wilderness area, in nomenclatural diagram of Barker (1979, p. 6). Symbols explained in figure 2 and text.
25 I I I III* 1 II MM MMs
40 0DUo
TONALITE
DO J-C 30 .CM EG SU \ BE »BU CP CD \ -CA 1 .MAt GRANODIORITE \ SG ^DH DM GRANITE CO^ (odomellite) 20 SF TE1
CH
10
DIORITE H0«
30 40 50 60 70 80 90 ANOR
Figure 18.--Diagram showing CIPW normative approximation of nomen clature to modal classification of plutons and gneiss units of the Glacier Peak Wilderness area, by the method of Streckeisen and Le Maitre (1979). Rock names shown are from density distributions of analyses shown in diagrams of Streckeisen and Le Maitre (1979). Q 1 = normative q/(q + or + ab + an); ANOR = normative an x 100/(or + an). Symbols explained in figure 2 and text.
26 SW 4kCD - SU FREQUENCY SG WG TE PL TEw SF JO RC SL DUh GR CO DUo DD MM MMs FO CM DM CP LC HP EG CG DH CA MA I DO CY HI BE CD BU BUd CH SI | RP| H0| 20 30 40 50 60 70 NORMATIVE PLAGIOCLASE AN PERCENT
SW SU SG RC O WG PL z DUo MMs UJ - ID DM JO B a TEw DH HP UJ CL TE CP HI U. SL CO GR SF CM FO MM 2-- SI DUh CD EG LC RP MA DD CA CG DO HO CH BUd BU BE CY 20 40 60 80 DIFFERENTIATION INDEX
SW TE FREQUENCY _ SG SU TEw - RC SI SL MM PL SF oo>ro LC MMs MA HP FO JO HI DUa EG GR DH DUh WG DM CP CO RP DD CY CD BUd HO I DO | CG BE CM CA BU CH 30 40 50 60 MG NUMBER
Figure 19.--Frequency distributions of (A) normative plagioclase compositions, (B) differentiation index (normative q + or + ab + an + ne), and (C) Mg number (see text) of plutons and gneiss units of the Glacier Peak Wilderness area. Symbols explained in figure 2 and text.
27 DATA REPORTS
Explanation of symbols
Field unit symbols that are used chiefly on summary diagrams of average compositions are explained in figure 2, except for those described below. BUd are dikes apparently related to the Mount Buckindy pluton (BU). Dlla and DUh, respectively, are hornblende-quartz diorite augen gneiss ana gneissic horn blende-quartz diorite of the Dumbell Mountain piutons (map units "dag" and "dhg" of Cater and Crowder.( 1967). MAt are samples of Misch's (1966) Marblemount Meta Quartz Diorite provided by Mi sen from his type area of the unit mapped (Misch, 1979) near the town of Marblemount just northwest of the Glacier Peak Wilderness (fig. 1). MMs are samples from southeast of Flat Creek (fig. 64) from one or more units possibly correlative with the Magic Mountain Gneiss as mapped in its type area by Tabor (1961). SWt are samples of Swakane Biotite Gneiss from its type area near Swakane Creek and the Columbia River, north of Wenatchee. TEw are samples from the Tenpeak pluton in the White Mountains area (White Mountain pluton of Cater and Crowder, 1967). The following symbols are used for rock names in the data tables A alas kite GAM melagabbro QG quartz gabbro AP a pi i te GD granodiorite QM quartz monzodiorite DI diorite GR granite TO tonalite G gneiss HB hornblendite X other GA gabbro MQ metaquartz diorite GAL leucogabbro QD quartz diorite The symbols "p and "f" used with those abbreviations indicate, respectively, a strong porphyritic texture or foliated structure, as in "TOf," a foliated tonalite. Modal compositions of some rocks are indiindicated in lower case, as in "Gto," a tonalitic gneiss
The following symbols in the data tables show mineral occurrences seen but not counted in thin section: tr, trace amounts; ^, small amount greater than trace but less than a few percent; and £, major amount.
Minerals of generally accessory type or of occurrence in only a few thin sections were not counted individually»and are indicated by the following symbols in the last column of the tables:
al- allani te r- rutile ap- apatite sc- scapolite c- calcite sec- secondary, undifferentiated g- garnet sf- sul fides k- kyanite t- tourmaline m- muscovite z- zircon P- prehnite
28 CYCLONE* LAKE
\TONALITE v n- \* BENCH ' LAKE A
V V V Crater _. A*??95!K/4. V II. CHAVAL
v v PLUTON ^ v - \x V\/M5jJf fcfc ^ 0 V^ \ X X ^-/OT^ N "\ f/ X ^ C^0 -48°20'
Figure 20.--Geologic sketch map of the Mount Buckindy pluton, showing approximate sample sites. Location in southern part of Snowking Mountain and west-central part of Sonny Boy Lakes quadrangles. Sites 16-20 are for dike samples and 21-23 for breccia-pipe samples from which modal data not obtained.
29 MOUNT BUCKINDY PLUTON
GRANODIORITE
QUARTZ MONZODIORITE
J2
V V V 35 K-FELDSPAR 10 PLAGIOCLASE
15.
10*
V V v v 30 20 10 QUARTZ FELDSPARS
Figure 21. Proportions of modal minerals of samples from the fat Buckindy pluton, showing rock classification i>i upper diagram.
30 Table 1. Modes (volume percent) and specific gravities of samples from the Mt Buckindy pluton. Averages exclude atypical samples 82S80A and 82S104A.
co agioclase rnblende o CL o CD 0 >> jr- >> f- to 0) o> X 1/1 CL M co o CD co i/> *-> 0 si C 4-> ^£ O > to "o i. to »- -o O CL) CD Sample O tJ O Q- t- o "oJ o-3 o to o CD No. O. OH CO CD Q_ *4- Q_ 1 E CO 31 LU 0 U_ CO 0
80F60A 1 TO 2.740 1.7 52.3 26.4 19.6 12.1 5.2 .1 .4 1.7 tr .2 (ap,z) 80F61A 2 TOp 2.737 0 66.3 17.0 16.8 10.0 5.3 tr .1 1.4 0 1 (P) 80GX2189 3 GD 2.710 7.1 53.9 25.7 13.3 9.4 2.6 tr .1 1.1 tr 0 80L19B 4 TO 2.705 5.4 56.0 23.7 14.9 8.0 5.7 0 .2 1.0 tr tr (ap) 81F107A 5 TO 2.705 1.8 59.5 27.2 11.5 8.1 2.6 tr .1 .7 0 tr (ap) 81F169B 6 TOp 2.708 2.5 58.1 21.8 17.6 10.4 5.9 tr tr 1.2 .1 0 81F172A 7 GD 2.697 6.7 47.7 29.4 16.1 9.5 3.3 .1 1.9 1.2 0 .1 (al.ap) 81F251A 8 TO 2.720 2.4 55.3 24.3 18.0 10.7 4.8 .1 1.0 1.3 tr -2 (al.p.z) 81N62A 9 TOp 2.713 2.7 57.5 24.1 15.7 6.0 3.4 .4 5.3 .4 .1 tr (c) 82F157A 10 GD 2.690 6.8 55.5 27.3 10.5 7.0 2.2 tr .4 .8 .1 0 82F310A 11 TO 2.720 1.4 54.5 27.0 17.0 9.0 6.3 .1 .5 1.1 tr tr (ap.z) 82S80A 12 QMp 2.691 26.1 50.1 4.8 19.0 s m 82S97A 13 TO 2.711 4.6 55.2 25.3" 14.9 8.8 5.0 .1 .1 .9 tr tr (z) 82S102A 14 QDp 2.710 .1 80.5 5.5 13.9 2.3 10.4 tr tr 1.0 0 .1 (al,ap) 82S112A 15 TOp 2.709 1.7 58.6 16.6 23.1 17.1 3.6 .3 1.5 .5 0 .1 (ap,p) 81F252A TO 2.703 1.4 57.3 25.1 16.2 11.4 3.4 tr tr 1.3 0 0 81N10A TO 2.708 5.0 57.0 22.1 15.9 m m tr tr tr 0 tr (ap) 82F154A QDp 2.708 1.1 66.1 16.3 16.6 m « m tr tr s tr tr (ap) 82F258A TOp 2.682 .2 70.0 20.2 9.6 m tr tr s s tr 0 82S83A TOp 2.695 1.1 55.7 23.0 20.2 m 0 tr m s tr 0 82S87A TO 2.726 .5 63.4 18.0 18.0 m m tr tr s 0 tr (ap) 82S98A TO 2.721 2.5 59.9 18.4 19.2 m m tr tr s 0 tr (ap) 82S99A GD 2.709 7.7 56.7 17.3 18.2 m m tr tr s 0 0 82S100A QD 2.741 .6 61.8 13.9 23.7 m m tr tr s 0 tr (ap) 82S101A TO 2.691 3.5 56.9 24.0 15.6 m s tr tr s 0 0 82S103A QDp 2.702 4.2 71.9 6.8 17.1 s m tr tr tr 0 0 ope i r\A[L 7 31 Q , QDp nd 0 59.5 8 ./ Jl .O
Average 2.710 2.9 59.5 21.1 16.5 9.3 4.7 .1 .8 1.0 .1 tr Standard dev. .015 2.5 7.0 6.1 3.3 3.2 2.1 .1 1.4 .3 -- -- 24 + 15
31 - 48°30'
CASCADE PASS PLUTON \ \ \
Figure 22.--Geologic sketch map of the Cascade Pass pluton, showing approximate sample sites. Location mostly in Cascade Pass quadrangle. Based largely on mapping by Tabor (1961).
32 CASCADE PASS PLUTON
GRANODIORITEX TONALITE
K-FELDSPAR 10 PLAGIOCLASE
r
____ 30 20 QUARTZ
Figure 23.--Proportions of modal minerals of samples from the Cascade Pass piuton, showing rock classification in upper diagram.
33 Table 2. Modes (volume percent) and specific gravities of samples from the Cascade Pass pluton
OJo OJ Plagioclase CL Potassium Hornblende OJ X o Specific feldspar Ol o z M gravity rsi Biotite M OJ M r 0 -oO i- c t. fO *^~ o Ol OJ Sample "o U M «*- r- 1 -C -C O O *0 CL JC OJ ex No. £ OC. 1- E UJ CO o 80S29A 1 GD 2.695 8.3 51.3 25.3 15.1 9.7 4.5 0 0 .8 0 tr (al) 81F218B 2 GD 2.711 7.2 53.1 20.6 19.1 9.0 4.3 .2 4.4 .1 .7 .3 (c) 81F221A 3 TO 2.728 3.0 55.2 22.4 19.3 9.1 8.2 0 .2 1.0 tr .8 (sec) 82F151A 4 TOp 2.750 0 58.2 16.1 25.7 9.8 14.1 .6 0 1.0 tr .2 (sf.ap)
Average 2.721 4.6 54.5 21.1 19.8 9.4 7.8 tr tr .7 tr .3 Standard dev. .024 3.8 3.0 3.9 4.4 .4 4.6 .4
34 I2I°00'
-48°I5'
Figure 24.--Geologic sketch map of the Cloudy Pass batholith, showing approx imate sample sites. Site 30 is for a chemically analyzed dike sample (not on table 3) with grain size too fine for modal determination.
35 r
CLOUDY PASS 21 BATHOLITH .£2* M .27
GRANITE QUARTZ MONZODIORITE'^^i%
19
I/ V V V \s K-FELDSPAR 35 10 PLAGIOCLASE
"cTlii \ \
30 20 10 QUARTZ FELDSPARS
Figure 25. Proportions of modal minerals of samples from the Cloudy Pass batholith, showing rock classification in upper diagram.
36 CO 00 00 CO 00 00 00 CO CO 00 CO CO CO CO 00 CO 00 CO CO 00 CO 00 CO 00 CO CO 00 00 00 CO 00 CO CO CO CO 00 00 00 CO 00 00 Ql -n oo oo oo z z z z z z Z 3 to to 4* to ro >-* -»J en en en vo to ro ro »-* > * co en en -p» to to to >-> ro J "xj en en 4* to co tn en » i O ^3 en en >-* tn >-* 4* o vo -J tn o 4* vo *^J ro Co en tn vo *-* t 00 4k >-* t to ro co en » *»J f» f» o ro co > > co tn vo > > > > 4k 4k CO VO CO » » DO > > oo ro > 0 > »
ro ro ro ro ro ro ro ro ro t vo oo **J en tn 4^ to ro i-> o vo oo *«4 en tn 4k to ro i-> o vo co -j en tn 4k to ro i-> Plot No. jo ertjo -H » « « CD CD CD » CD CD CD 1 « CD \JO CD CD JOJO -H » -HJO i i CD -H CD CD CD CD -H » CD CD » o o o o o O O O O O O O 33 73 Oo O O O 0 O ^33000 o o o o o o o o o o O O O O ;o Rock type o> T3 T3 T3 T3 T3 a T3 ^3 ^3 cr ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro n *j »«a en en *»J -j ««4 vj «»j en Specific -J ro -J co ro to ro >-* »-* vo tn co to o tn >- ro ro 4* en »-* vo 4* ro to 4k en tn ro tn 4* 4^ ro ro i-» *«J ro ro vo o to »-* 00 to vo >-* gravity * tn tn -j o en 4k to tn o tn o o co tn o O O tn o tn O tn tn o O co co o tn tn -j tn o ro o i ro ro ro ro » t >- co Potassium vo ro ro ro co 4* en co co i-> 00 tn to co 4k 00 tO l-> co oo to tn ro ro ro tn to en to en vo ro tO tO tO 4k 4k o en o ro i-» vo vo tn -J 4k vo -j ««4 tn ««4 tn en o *-J 4* "*J >-* en co »«a ro feldspar CL ro to o *-* i-> ro vo 4k to 4* 4k -J ro co n>
en tn en tn tn tn tn tn tn 4* tn 4k 4k to tn tn tn tn -^ 4k 4k tn en tn tn tn en tn tn tn tn 4* 4k tn 4^ 4k Ul 4k 4k tO oo co o en co _ ,_. en > oo tn 4k to co H^ >-* o tn en » »- >-* CO O 4k ro vo vo o **J vo ro vo tn oo Plagloclase -h 0 vo vo tn oo co ro ro 4* ro tn 4k - j >-* en » vo 4* vo ro > ro oo oo en 4k ro ro oo vo en co en 4k *»4 ro tn 4^ tn o 00 -i o c » >-* ro >-» »- ro H- ro ro »- >-* ro ro »- ro ro ro ro ro »- ro ro »- ro ro ro ro i-» ro ro »- ro »- ro ro »- Co vo ro 4^ *«J tn to t en *«J ro en en o to oo vo to vo to i-> ro ro oo 4k to en en o ro o o vo ro o *"J tn oo to tn to Quartz r+ »- 4k to >-* CO »- o vo tn -j -»j o 4* >-* tn 3TT3 o vo to tn t co vo en o *»J en co o ro en to oo co oo o co oo en tn oo n> n> CO ro ro ro »- ro ro ro »- >-* ro ro ro ro ro ro ro »- ro ro ro ro >-* ro »- ro ro H- 0 0m 4k O *"J *xl O tn o *»J *«J >-* 4k en oo -J -J 00 00 VO *»J O oo -J vo vo vo tn en to vo to o -J »- 00 to (- tn to tn ««4 Total O 3 mafics C rf tn >-* o en >-* CO CO ««4 ro 4k tn -j co en -J 00 ro co co ro >-* oo co vo -J tn co »- en ro oo i-> 4k oo en 00 to to to »-> ex. >
t H^ t-» >-* » » >-* >- ro >- t * Ql ro en 4* ro ro »-* -*J to >-* tn oo ro co (_ tn ro vo to ro o vo **J i en to to -J T3 3 u> 3 3 3 3 33333 Biotite Ql CX. N-* **j to vo en to en ^o u^ to vo en ro en vo en tn vo ro 4k i_> oo »- »- ro to en co
A N A * V V « £ 0 A >-* t >-* >-* *% 01 n tn (- o tn en "*J vo ro to o 00 en tn o *^i -J oo en tn tn vo oo »- to I VO 4k rt- - 33333 33333 Hornblende tn -"J vo t 3T -h en o vo 4k » 4* ro o - ro o 4k vo en vo to to ro co en CO to O VO CO O * >-* ro o rt- O ri- r* ct- O O if O O c* r* O O O o « o o o o « o o o « o o o . 0 0 rt- if O O O VO Pyroxene rt-lQ -1 1 -1 1 o tn ro IT 1 Ql O . O « o o n- O O O en n »- i-> i-> 4k t CO t >-* Epidote 00 »- ro tn -i oo co »- ro en en r* -J to ro tn to i-> ro 4k re 3 n- n- «» ' if if if U» U» r* Chlorite o 4* en -J -J vo tn 4k o tn -1-1 -I -S n T T to ro 4* *»4 4k 1 CO CO O o to >-* co en -i o co co en o >-* >-* o « « u> to T to en to oo co -J ro 4* 4k vo ro tn oo 4* >-* en ro ro tn ro 00 Fe-Ti oxides Ql 3o if O if if if o o . o o o O 0 O rf O o o n- o o O O O if O rf 0 * -i -i »- »- -1 Sphene ro -1 -1 -1 -1 -i ro »- co ro »- »- V*
O if if if if r* O O O O r* r* rt- O ft- « ct- O rt- rt- rt- rt- rt- rt- O O Others -5 -5 -1 1 -1 -1 -1 -5 -1 T »-* 1 1 to »- ro T »- T >- »- T »- ro 1 -1 1 1 -1 »- -1
Ol Ol Ol T3 Oi Ol Ql T3 (/> Ol N T3 Q» Ol Ol T3 T3 "O N Ql Ol O> N T3 T3 T3 T3 T3 < T3 T3 T3 "O T3 T3 ^ »~^ fD -^ XJ T3 « ' « "-^ « ' O . f>l TM ^ o-' N T3 T3 T3 T3 "g -^ > N N N Table 3.--Continued
o» a» a*o O> o Q. u c a» a> ~r- V> i ia a* a* c a> X t/> Q. 0 N a* o o> i~ !" i/) i * > 0 *» JQ X o ^ r- c £. * 0 > ^3 ^3 I. ia > C o T3 o l o> a> Sample Q) ta to *0 M «*- 0 -C 0 0. S. O 0) f ^D lO O >^ o. -C a> a. No. t/> en Q. «*- a_ cr 1- E 03 :r Q_ LU to o
81N38A QMp 2.713 7.7 59.0 15.0 18.3 S m 0 tr m S tr tr (sf) 81N68A TO 2.765 1.8 57.5 17.1 23.6 m < m 0 tr m S tr 0 81N100A TO 2.713 5.4 50.7 27.1 16.8 (I) is. m 0 tr s tr 0 tr (ap) 81N108A GD 2.728 7.2 53.6 24.2 14.9 m > m 0 tr tr tr 0 tr (ap.z) 81N153, TO 2.702 4.5 56.4 22.9 16.2 m < m 0 tr tr s tr tr (ap.z) 81N158A TO 2.718 3.3 51.1 22.0 23.5 m <. m 0 tr m tr s tr (ap) 81S33A GD 2.715 11.0 51.6 20.2 17.2 m > m 0 tr s tr tr 0 81S38A TO 2.745 4.1 50.7 20.2 25.0 m -as. m 0 0 tr tr 0 tr (ap.sf) 81S40A TO 2.678 1.7 56.1 29.9 12.3 m s 0 tr tr tr 0 tr (ap) 81S40B TO 2.730 4.7 57.2 19.8 18.2 m x m tr tr tr tr 0 tr (ap.al) 81S43A TO 2.722 .1 51.6 31.4 16.9 m > m 0 tr tr tr tr tr (ap) 82G52A GD 2.660 15.4 45.0 23.9 15.7 m tr 0 s s tr 0 tr (sf) 82S19A TO 2.755 5.8 53.9 21.2 19.1 m s m tr tr s 0 tr (ap) 82S20A GD 2.683 15.6 52.8 19.1 12.5 m 0 0 tr s tr tr 0 Average 2.716 7.8 52.7 20.2 19.2 9.3 7.0 0.2 .2 1.6 .6 tr tr Standard dev. .039 7.8 7.0 5.4 5.3 4.6 3.7 0.5 .3 1.7 .5
54 29
38 SOUTH CASCADE GLACIER iSTOCK 48°22'
Figure 26.--Geologic sketch map of the South Cascade Glacier stock, showing approximate sample sites. Chiefly from mapping of Tabor (1961).
39 r SOUTH CASCADE GLACIER STOCK
-K-FELDSPAR »0 PLAGIOCLASE
\
I «4 ALASKITE V v v 80 QUARTZ FELDSPARS
Figure 27. Proportions of modal minerals of samples from the South Cascade Glacier stock, showing rock classification in upper diagram.
40 oo y» oo oo oo oo OO 00 OO OO OO CO Ql tv ro Z 3 3 -» O "D Q. 01 £££2 CJ CJ CO »-* 1 ' « Ql IQ *«J tn -f* 3» en tn ^ cj ro ro T ro o 3» 3» ^> ^^ "^ ^> ^^ o* Q. cr tn ^ co ro H-* Plot No. ro
"S> \ i 1 i (O O O O O(O O O O Rock type i ro ro ro ro ro ro ro ro ro ro o Specific Q. o en tn " J "»j en en en ""j ""J en ro en er» j i o tn ro ro ro -J gravity ut » 00 vo en tn o *» 00 -J O -J CJ ro ro ro o tn co co o co en Potassium 0 »- tn ro en *«j co o .& **J en *» feldspar c ro ro tn tn tn co co en tn tn co -a 0 OO vo »^ o tn i ' Plagioclase o n *» tn tn ro tn H- en tn -j ro en C 1 r*3* Oro ro co ro ro ro co co ro ro 0 rt- en oo *» ro «>i 00 co "-J ^ en oo Quartz vo ro O -J H- -vl vo vo **J ^ ro O 0» ro i t ' ro H- i 0. Q. -J ro »- ro ^ co en cj co ^ cj Total fD 2"}§in VO *J ro en *vi vo £> ro vo oo oo mafics » o t ^ o -* -* -«« tn tn 0 3 3 r* H-> 00 *^J Biotite ro H-« er» co ro en ^ ^ 1 O V (/> (O ro H-« en H- 0 3 ui o O O r* Hornblende O Oi er» tn o tn -j o < rt- I r* O r* rt- r+ r* r* rt- E pi dote n -» -I 1 -»»- -» T ro i/i r * tn ro tn j* tn 0 fT>^ fr>« Viy> S3a Chlorite CO 00 "»J -^ en ro en VI Oi 3o^ r* -» !-» r* H- CJ ** ro tn ro ro Fe-Ti oxides ro
O O r* r* '^ T ro U '^ Sphene ro ro -» T ^ Q «/» r^- ri- !-» =1 i ? T T T" T T Others r*3- 3 Oi Oi 3 n n 01 T3 o« ro
*^* N - « N n -4e°i5'
Figure 28.--Geologic sketch map of the Railroad Creek pluton, showing approximate sample sites. From mapping of Cater and Wright (1967) south of Flora Mountain, Tabor (1961) north of Agnes Creek, and Libby (1964) in intervening area..
42 r
RAILROAD CREEK PLUTON
K-FELDSPAR 10 PLAGIOCLASE
-A\
30 10 QUARTZ FELDSPARS
Figure 29.--Proportions of modal minerals of samples from the Railroad Creek piuton, showing rock classification in upper diagram. Cater*s (1982, p. 80) average (upper diagram) for southern end of body (Lucerne quadrangle) marked by "+."
43 CO CO CO CO CO CO OO CO CO 00 CO CO CO CO CO CO 00 00 00 00 CO CO OO CO CO CO OO 00 00 00 CO 00 OO OO 00 CO 00 00 OO OO oo ro ro ro ro t-* Ol CD -n -n co co oo z z z z CD -n ~n -n oo CO CO Z Z Z Z 3 x» co en H- >- t ro ro ro ro ro ro ro - en en H- H- >- x* co en en ro ro »-«i-« co co ro ro ro ro »- en en x> x* x* O TJ x» ro -«J Co en en o vo ^J ro oo co o o ro co eo x» o en x^ en x> x* CD ro »-« vo oo en 3> j> en en 3> en co en en en n> CO J>
ro o vo oo ^»J en en x* co ro H- o vo co *«J en en x» co ro H- Plot No. H CD -H 3* 5> 3> 3> -H a> 1 -H CD -H -H 1 5> ,O -H -H -H CD CD.O CD CD -H CD -H^O -H CD CD -H 1 CD -H -H -H -H CD CD O> O OCO CO .O r* Oca O O o o o Oca O O O O O 00000 O O O O O O O O 0 0 0 O O 0 0 Rock type a- n n 3 0 0. -h -h n -h ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro n Specific en en en 3 en en en en 3 3 en en en en en en en 3 3 en en en en en en 3 en *«j '-J en en en -J en ->J en en en en en en en co >-* Q. en en co X* o. o. ^J vo en co ro vo en a. a. en en co ^J en co ^J CO ro en ro vo co vo en en gravity i 0 CO ^1 O o ro en o x» en * >j CO O vO *«J co en *sj ^J O CO 00 0 Lft f^ f^ L^ft en ro o o ^J en i ro ro ro o en x» vo en co en ro ro co en eo > en en ro en x» en vo *«J co »- en ro en ro oo vo co eo » eo ro x* oo o Potassium 0. ro eo co co co vo x> o ro o H- vo eo eo en en ro ro CO *^J VO » i-^ eo vo o VO "-J CO ^J CO feldspar n>
en en co x> ^J ^j en en en en en en en en co -«j en en en en en en x> en en x» en en en en en en en en en en en en en en en en en x» vo ro en en co en ^j co en ro en ro en co en en en »«j vo ro co CO Lft ^- f.^ X^ en en en * co Plagioclase -»> 0 o x> en H-» H-» n * vo "J o co en en ro H- ro vo ro vo ^J ^J ro en o Xk en vo * o vo co ro >_ ^J H- X» 0 en en co en o o c 3 3 co ro co ro H- ro ro ro ro ro ro ro ro ro co t ro t co ro ro co ro co co co t ro ro ro ro ro ro ro ro co ro co ro n> o en H- ^j o x* en vo en co x» oo en ro en en co o en en x* ro Co o co >- x» ro oo CO en en en i en *- vo o co r* Quartz n> ft> O vo O en en O CO o en en o ^J o en co en en en en ro ro o H- ro co co en en en vo *sj co en x* »«J vo co ro t-» en n 50 O o> n> i >- i i » *-* _.. 3 oo ro co ro >- ro >- ro ro co ro 00 en *J x* o »- ^J ^J ro VO O CO O ^*J vO ^*J CO 00 vo o en ro x> ro o o vo co Total ' r* en x* ro en i 1 mafics n CO ro co en en CO ro ^J ro H- en ^j vo ro en ro en vo CO eo o en o H- en co co en x» co >- ro x» ro co o CD Ol O. 3 1 1 0 en co ^J Cn en en ^j co vo en co ^j ^j co en Q. 3 O o o n- r+ i/> 3 3 3 3 3 3 i/» i03i- Biotite n /> n n en f^ tf^ ^p Lft ^rt Lft js. ro Lft ^n en ro o *»J *»J vo x* en co en n> TJ r^ CD ro ro H- t-. H-> CO ?« o r* r* O r* r* O O O i/» i/» i/» i/» ,-» n- O I 0 3 I f Hornblende TJ -h n n n n n n 1 1 CO en ro ^J en ro ^j en en ro H-» en > n ro vo x> vo en C O r* r* r* O O rf O rf O rf r* 0 r+ n- 0 0 i r* rt i r* r* O «-» rt- r* r* Or* Epidote o ca i n n i n n en n ^J n n H- -i co ro H- H- T i >- n »- i 3 n a* ro en H- H- ro ^ v> 3 to in in i 3 v> i Chlorite r* i i -P» en
n- in to in r+ O n n H-» x» ro »- H-» n ro x* ro >- H- ro ro »- eo ro co ro en ro Fe-Ti oxides -»»
in rt 0 r* 0 ON O r* O rf r* O r* O rt rf i r* r* i r* rf r* r* O r* r* rt> r* O r* r* O O r* O O rf O O Ol n n n n n n i n n i n n n n n n »- n n n n n n Sphene
r* r* i/» O r* «/» r* r* r* r* rt- r* rt rt d- I O d- I d- r* r* c* r* r* r* r* r* r* r* r* r* r* n n n n n n n n n n n n i n i n vo cn n >- n > n n *-* n H- n n n n n n *- n n Others in
CD CD CO Ol CO Ol CD O« Ol CD Oi CD ISI Ql fsi Ol (/> in Oi Oi D> in 01 a* a* 01 CD a* 01 01 01 ft) TJ TJ TJ TJ P7 3 2, o o --^ n « ^--« N 0 ^ (M N (M ISI N IM v v Ol Dl m-,^ Qf QJ fM ISI Ol Ol CD 01 a* Ol Q» 'TJ TJ TJ TJ Table 5.--Continued
(A QJo QJ Plagioclase r- CL Potassium Hornblende X >> Specific feldspar QJ Chlorite O M gravity N in Biotite 4J QJ l/> M o O r C i_ ^C i_ ID 'r~ a 1- QJ OJ Sample M «*- r- O 10 1 jr No. o o-3 og CL QJ CL M ex: LU Lu to 0 82G45A GO 2.690 5.8 51.8 25.5 16.9 tr m tr s tr tr 0 82G47A GD 2.642 9.9 52.5 31.7 5.9 s tr 0 m tr tr tr Up) 82G54A GD 2.610 6.9 56.6 29.4 7.1 m tr tr m s 0 tr (ap.z) 82G55A GD 2.650 7.4 63.1 23.5 6.0 m s tr s tr tr tr (ap) 82S14A GD 2.654 8.8 53.1 27.1 11.0 0 tr s m s tr 0
Average 2.671 7.3 56.9 26.1 10.7 8.3 1.0 .1 1.2 .2 tr tr Standard dev. .03 6.2 8.1 5.1 3.9 2.5 .9 .2 1.2 .1 39 - 45 - 21
45 I20°45'
-48°05'
Figure 30.--Geologic sketch map of northern part of the Duncan Hill pluton, showing approximate sample sites. From mapping of Cater and Crowder (1967) and Cater and Wright (1967). As shown, includes contact complexes mapped separately.
46 DUNCAN HILL PLUTON
V -K-FELDSPAR 10 PLAGIOCLASE
30 10 QUARTZ FELDSPARS
Figure 31.--Proportions of modal minerals of samples from the northern end of the Duncan Hill piuton, showing rock classification in upper diagram. Average of Cater 1 s (1982, p. 63) modes for entire body marked by "+" in upper diagram,
47 ts> j» CD CD CD CD CD CD CD CO 01 r* < rorororororororo QI QI CD 3 -J O ^3 CL. QI QI to n> -$ ft» CL. a. ^ cr» in *» u> ro n> Plot No. -H oooooooo Rock type CT ro rorororororororo Specific n> O -J cn CD ro ro gravity CD O i 3: i i * oo ro i-* Potassium 0 OL u> ro to ^j CD ro ji in vo feldspar n> (/>
< Plagioclase o ro ««J
ro to H-« - i-* - ro 3i3 m »-J CD oroLou>vovoin»-> Quartz ro u> ?! i - ro H-« ro *- 1-* 00 Total in CD mafics II
!-* I-* is F» vo in J *vj o.) «^ .6k r~> 3 ...... Biotite i a- i O -6k **J in CD ^ °* V -^s ro ro - CJl u> -S* o ° Hornblende c'S ro a* (ji in CD u> CD i cT" 1 -j T T -* T T Epidote 3<5
ro H- i i CTl -t» Chlorite < 4=> CD «-» n> (^ Fe-Ti oxides cn en o -h rt- - >- -e» cn Sphene ro -* O u> vo ro 3
« » r* «-^» n> *» u> T i-*1 ** » 1 ! Others
^^ n -^^ O QI - C"> < T3 "O IM
o -on CLARK MTN STOCKS
K-FELDSFAR 10 PLAGIOCLASE
30 20 10 QUARTZ FELDSPARS
Figure 32.--Proportions of modal minerals In samples from the Clark Mountain stocks, showing rock classification in upper diagram. Geologic sketch map of stocks shown in figure 47. "+" in upper diagram shows average of Cater 1 s (1982, p. 54) modes.
49 CO CO CO CO CO CO StandardAverage ro ro ro ro ro O> -n -n en -n -n Z 3 i i in i i o -o o co o> o o ro 3> 3> co i n> 3> 3> 3> o. co ro t-> Plot No. n> t t IjO -H Rock type O O O O O 01 cr ro ro ro ro ro ro t~*i ***j Specific CO 4* vo vo ro 4* in gravity CT» o ro -« co ro o
> co ro - o Potassium O Q. 4* O> Co o ro co feldspar n> in vo in ^J co 4> Plagioclase -h O 4*- 4^ O> CO O VO "I * o c ro ro ro co - ro 3 3 O> 4* en ro ro in cx» n> Quartz r+ ro co co -^i vo vo in n n i Total <-> on CO 4* vo i * o> in o* a cn "^J CT» o --J o i ro mafics O 3 o> ro ^J 4k CO O O 3 3 3 ... Biotite C O. VO CO o> in ro =1
ro . . o o o o Hornblende 3 O ro v* -h
CO CO vj ro O O v* rt- r* Muscovite O cr» ro -» i-1 -1 O>
4* in 4* 4> t/t t/» ... Epidote en 4k t->
»-» O « « o I -i ro ro Chlorite
I -i -i !- i-1 ro Fe-Ti oxides Dl 73 i/» t/t « « . l-» CT» in "^J **J Sphene
w» »-» r* *-» r* 1 -1 -1 -1 -I "» Others
CV O» O» D» -Q ^-~ o^
N I20°SS'
SWAKANE v BIOTITEX ^GNEISS
48° 05'
Figure 33.--Geologic sketch map of the High Pass pluton, showing approximate sample sites. From mapping by Cater and Crowder (1967).
51 r
HIGH PASS PLUTON
K-FELDSPAR 10 PLAGIOCLASE
30 » 20 10 QUARTZ FELDSPARS
Figure 34. Proportions of modal minerals of samples from the High Pass pluton, showing rock classification in upper diagram. Average of Cater 1 s (1982, p. 40) modes marked by "+" in upper diagram.
52 CD CD CD CD CD CD CD CD en StandardAverage ro ro ro ro ro ro ro ro o> o o oo o CD -n ~n -n Z 3 en en 4k en 4>> ro » » C? ^3 \o 3> o CD 3> e*> »- O n>
0. en en 4k e&> ro »- n> Plot No.
-H -H 3> O CD Of (O (O (O O CD to O O Rock type o. o. o. -tt CL -h cr m ro ro ro ro ro ro ro ro ro Specific o en en en en en en en en en CD CD *- en 4k 4» en en 10 -»J en <>u gravity en 4» CD en eo
ro -vj UD O VO en ro co CD *^ Potassium en en ro o ro »- e*> co en »- feldspar
en en en en en en en en en ro co CD en *>j en ro o en »- Plagioclase *-J \O CD CD en Co en ro vo ^J
ro ro ro ro e&> ro ro ro ro en CD *-j o en en co en Quartz vo ro ^i eo o OO ^^ OJ K^ CA^
en e*> 4k 4* en en 4k en en Total O ro ro vo Co o en *^ **j \o mafics Ol s
4k 4k 4k 4k 4» e
i r+ o o c* o *- T Fe-Ti oxides
(Xt »- e*> eu 4» en ro ro i Sphene Of ao i i ^^ W i i T -i ro n Others
N Ol til n> fl> « ^ o> n n 01 M Ol -o - - ^-^ O» XJ
IM " 2, 121° 15'
\ X x x JORDAN
48°25'
CHAVAL VM/ChevYl
v PLUTON
Figure 35.--Geologic sketch map of the Cyclone Lake pluton, showing approximate sample sites. In part, from mapping by Bryant (1955).
54 CYCLONE LAKE PLUTON
K-FELDSPAR PLAGIOCLASE
r \ 11 \v * 1 * \ ^ \% 1 '*v 4" e *2 \, ALASKITE y y v ^ \ +- 30 20 10 QUARTZ FELDSPARS
Figure 36.--Proportions of modal minerals of samples from the Cyclone Lake pluton, showing rock classification in upper diagram. Dike or other small body possibly related to pluton marked by "+" '(upper diagram).
55 CO CO CO co OO J> CO CD CD CD CO CO CO CD CD CD CO CD CD CD CD CD CO CO CD CD CD OO O * i * Ql If < z -n z QI ro =z 3 .£» t t ' 3 -I cn ^- vo » » t ro ro ro co cn » » co ro ro ro > H- » o -o *» CO O d 01 y» - cn 3 Ql vO ro J> CO T ro \ d Of d. Plot No. -H cr ro Ql -h cr vo ifvOOififlQ vOVOtOVOO(OO
i i i n Others w ^-S-S-S^ -S-S-S-S-S ^-S^P-S -S2.-S-S-S
O M Ql MM 121° 10'
48°20'
Figure 37.--Geologic sketch map of the Downey Creek pluton, showing approximate sample sites.
57 r
DOWNEY CREEK PLUTON
K-FELDSPAR 35 10 PLAGIOCLASE
\
ALA5KITE \/ \/ v 30 20 QUARTZ FELDSPARS
Figure 38.--Proportions of modal minerals of samples trom the Downey Creek pluton, showing rock classitication in upper diagram. Dike or other small body possibly related to pluton, or to Cyclone Lake pluton, marked by -+- (upper diagram.
58 CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO * I--4 i > t~~i CD CD Dl O t t i O O O O o* Average2 Z 3 Average2 z. 3 dev.Standard vo *-J ^J t tn o -o dev.Standard 1 ' CO *-J t ! * VO VO o -o *-j ro co cn o o to o vo -P- rocooco»-« n> > n>
l *-4 cn cn -PI to ro t-1 Dl Plot No. _, cr Dl C*-VO Id r-MQ VO VO CO «-HO VO VO CDvO VO O CX CX O O. CX O. n> O-OT CXT-h-ICX Rock type 2 -»» -h fD ro ro ro ro ro ro ro o rororo rororororo CO Specific o CD cn cn cn tn cn cn cn cn CD cn cn cn cn en cn cn cn cn »- ro -« -' VO -P» CO »- .P> i OO »- CO -P> t co ro ro tn -P> 4=» gravity ?" CO CO en vo ro o tn cn ro tn cn i ro i ro i n> o 9 t i-* ro ro ro ro CO CO -« CO tn .** co »- ro VO -P- «- i ro co en .pi CD Potassium if *-J CO co ro CD tn ro co -P* cn vo o CO vo o cn feldspar S" tn tn cn tn -P> cn tn tn tn -p. tn -Pi co -Pi -t» tn ro -P> cn cn cn co vo tn cn o -p« tn °. VO -P» co co ^^ to *~* **J cn vo Plagioclase -»,o VO CO *-j t-« ro o ro ro co * 3 i ^j cn o cn ^ *-j ^ *-J ro ii ro co ro ro ro ro ro co 3 ***-o CO ro -Pi co ro co ro -^ co fD ro co CD cn .** vo co cn o vo cn cn cn CD *-J "Co Quartz ?-o ro ro -P« CO co *>J cn -Pi tn D> o_ "* to tn cn co o .** co cn ro co n> n>-i cn 2 ~5 o o O> o ^. t t-« ro co «- ro «- to cnroro corotnroro Total i 3 CO *J cn CD vo co o cn co CO *-J t *-J to ** cn co mafics n^ 1 Dl n 3 t-« ro ro ro -P« «- ro rf in in in tn in «-» fen »,J Biotite m °~ cn o cn vo co ro > CD tn 1" n> t (^j -« ro -P« i co tn -« tn <-f CD ro cn to o*
l/ii/t in in in r+ in « * « * » « * O !I^" t t nroT nt-«rocoT Chlorite ^ 3 in n> O r*-» O »« * -h t t Fe-Ti oxides 0 -I -I -I 1 T ro T T ro «- »-* -h tn r*- r*- CD O O O r*- Dl « r*- r*-OCD CDCD» OCD -I 1 -I 1 T -I H- Sphene 2 T3
f» r*- r*- r*- O r*- r* n> ro «- T -I 1 -I 1 tn . . i CO *-J -jotn ^* -i -j ^* co Others £
IQ tM Dl Dl VO Dl M TQ *CJ ^*"T3
Ot o* -o -48°a5'
Figure 39.--Geologic sketch map of the tonalite of Bench Lake, showing approximate sample sites. Correlation of area east of Downey Creek with main unit uncertain.
60 TONALITE OF BENCH LAKE
t ! v V V V VV V \\ *-K- FELDSPAR 10 PLAGIOCLASE
to« ALA8KITE
SO 10 QUARTZ FELDSPARS
u of modal "^rals In samples from the of Bench Lake, showing rockin breccia classification. pipes + »
61 r- E IM CX CX. r
IM IM IM £ IM IM CX r r- -EN
CX CX CX CX CX CX CX CX CX eX"~>"~> »r CO CVJ i/i CM co r^. r in vo vo ^- in co p>. auaqds . . . ..o-» .«..O vivi -H i_ CM i- co t-H o t-H m CM cn co CM t-H cn r-^ cn co t-» oo CM u i- u u u in vo . 4-> . 4-> ...... *. mUt+*+J+J+J4->VlvtVIVI co r-^ CO tr> co r-l CO t-H ^H 1_ 1_ t_ . 4->tsttsttsttst wiwi+Jinwi** «- 01 en.* CM t. , OOOOO OOOOO O O + > O o O O O O OOOOO OOOOOO « auaxcu/d r-l «£ .c in CM «» ON 10 td CLOUDY^. + PASS BATHOLITH Figure 41.--Geologic sketch map of the Sulphur Mountain pluton, except for small areas in Hoi den quadrangle to southeast (Cater and Crowder, 1967), showing approximate sample sites. 63 r SULPHUR MTN PLUTON 20+ GRANODIORITE V v_ K-FELDSPAR PLAGIOCLASE V 40 30 20 10 -QUARTZ FELDSPARS Figure 42.--Proportions of modal minerals of samples from- the Sulphur Mountain pluton, showing rock classifi cation in upper diagram. Samples from small separate areas in Hoi den quadrangle to southeast of main mass are marked by "+" in upper diagram. 64 Table 12.--Modes (volume percent) and specific gravities of samples from the Sulphur Mountain pluton. Samples 80F112A, 81N150A, 82F211A, and 82F212A are atypical and not included in averages «/> 65 -48°30* MARBLEMOUNT V RozorbockA Mtn X Figure 43.--Geologic sketch map of the Jordan Lakes pluton, showing approximate sample sites. In part, from mapping of Bryant (1955). 66 r \\ JORDAN LAKES PLUTON K-FELDSPAR 10 PLAGIOCLASE \y \/ \/ 40 30 20 10 ' QUARTZ FELDSPARS Figure 44.--Proportions of modal minerals of samples from the Jordan Lakes pluton, showing rock classification In upper diagram. 67 Co 3> CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO n- < D> 01 n Z 3 3 -1 cn » » > > co co co ro ro ro » » co » » co co ro ro -e* o -c^ 0. 01 cri4>co-J o en .e* co en coooocncn cn ;>;>»-»»-* cn o ** cn 3> 3 01 ta 5»5>3>5» iO3>3>3>5> CO co 3> co ro j» t-^O 3>3>3>m a> -» n> 5» 3> 3> J> J> ex ex » »» » a> rot-* oiooo-Jo* cnJ^coro*-" Plot No. < « -H tr> « i tr> tr> « tr> I-H-HCT> i t « cr> I i cr> < « «tr> C3OC3O C3OC3OC3 OOOOO C3OC3OC3 OOC3OO Rock type o? -h -h -h -t» -h -h cr ro rorororo rororororo ro rororo rororororo rororororo Specific "* rs> O CT» ^J^vlCTI-^J «»JCT»CnCT»CT» »«J3CT»CT»CT» '^JCTlCncn'^J CTl'^JCn'^JCTI (A> ro vo ro i » ««j ^ co oo 4> CT» *^i ocxottooo roooio^o * CD o to *^j gravity ^ ro J» o co co o ooo-«Jco co 4>rocr» U3 cx> co co cn cocnoocn 4 i »- »- co en ro co co co ro'^icnj^'^i » 4>CT»cn cocnu>4^cn CD -C» ro » «^J Potassium ^ rx> 43ft en 4^ ro4>-»J-»J »-» cn co ~-J co co j^ cn cn cn »->O94>coco -C» en ~-J CO CO feldspar g. n> in en cn en en en encn4>cn4> cn cn en cn en cncn4>cnj> cn cn cn cn en co ro o cn cn o en cn CD -O '3 M M « D> D> |S|. «-^ v ^^_x -w-"^^ (SI 3 M ' ' 0 T3 SLOAN CREEK PLUTONS 48°05' Figure 45.--Geologic sketch map of part of the Sloan Creek plutons, showing approximate sample sites. In part, from mapping of Vance (1957). Country rock schist and gneiss probably contains additional members of unit. 69 SLOAN CREEK PLUTONS K-FELDSPAR 10 PLA6IOCLASE V V V so QUARTZ FELDSPARS Figure 46.--Proportions of modal minerals of the Sloan Creek plutons of the study area, showing rock classification in upper diagram. 70 Table 14.--Modes (volume percent) and specific gravities of samples from the Sloan Creek plutons i/i 80F104E 1 TOf 2.753 tr 62.1 15.9 22.0 tr 12.0 .9 8.2 .5 .2 .2 (sec) 80R122A 2 TO 2.706 tr 60.9 23.0 16.1 9.5 4.6 .4 1.0 .3 .2 tr (ap) 80R136A 3 TOf 2.737 .2 58.0 17.2 24.6 7.9 10.9 tr 3.8 .3 .3 1.4 (sec.p.m) 80R138A 4 TOf 2.721 .2 56.7 17.7 25.4 10.5 12.2 tr 1.4 .4 .1 .7 (sec.p.ap.m) 80S5A 5 TOf 2.732 .2 59.4 19.8 20.7 10.1 7.9 tr 1.4 .5 .2 .5 (p.ap) 81F312A 6 TO 2.805 1.3 51.9 16.0 30.8 13.0 11.2 tr 4.9 1.4 tr .3 (sec.ap) 81S48A 7 QD 2.760 tr 62.6 10.0 27.3 2.7 21.7 tr 1.7 1.2 0 tr (ap) 82F160A 8 TOf 2.762 0 57.6 15.9 26.5 12.7 12.9 tr .3 .1 tr .4 (p) 82F162A 9 TOf 2.760 0 49.0 16.8 34.1 13.0 19.5 0 tr .5 tr 1.1 (P) 82F272A 10 TOf 2.758 0 57.9 17.6 24.6 16.3 8.0 tr .1 .2 tr tr (ap) 80F104A TOf 2.723 .1 63.1 26.7 10.1 tr s s m s s tr (ap.m) 80H140A QD 2.762 0 57.7 12.6 29.7 m < m 0 0 s 0 tr (ap) 80H140B TO 2.769 1.0 54.6 20.5 23.9 m < m tr s s 0 tr (ap) 80H141A TO 2.750 .1 58.4 23.9 17.6 m * m s m s 0 tr (ap) 80H143A GD 2.720 7.4 57.3 23.0 12.2 0 s s m s tr tr (ap) 80R121A TO 2.700 tr 65.0 26.6 8.4 s 0 s m s tr s (m) 80R135A TOf 2.675 .6 59.6 26.0 13.8 tr m s m s tr s (P) 80R137A TOf 2.685 2.1 55.0 19.5 23.5 0 m tr m s tr s (p) 81F313A TO 2.698 2.1 54.8 34.5 8.7 s 0 tr m s 0 s (p,m) 81F318A QD 2.780 .8 66.2 7.3 25.7 m 0 tr m s tr tr (ap) 81S49A TO 2.720 .4 57.9 17.9 23.8 s m tr s tr tr s (p.sec) 81S50A QD 2.812 .2 60.9 6.3 32.5 0 m s s s tr s (sec) 81S53A GD 2.855 0 51.3 11.7 37.0 0 m s m s s s (sec) 81S55A TO nd 1.2 61.6 19.1 18.1 m «* m s s s tr s (sec.p) 82F270A TOf 2.739 0 57.1 16.6 26.3 m * m tr tr s tr s (ap) Average 2.745 .7 58.3 18.5 22.5 9.6 12.1 tr 2.3 .5 .1 .5 Standard dev. .042 1.5 4.1 6.4 7.8 5.0 5.2 -- 2.6 .4 .1 .5 24-* 25 * 10 71 MOSTLY VOLCANIC ROCKS OF * GLACIER PEAK 48°00' Figure 47.--Geologic sketch map of the major part of the Tenpeak pluton, showing approximate sample sites. From numerous sources, as shown by Ford (1983a). 72 TENPEAK PLUTON- western area K-FELDSPAR PLAGIOCLASE 30 20 K> QUARTZ Figure 48.--Proportions of modal minerals of the area of the Tenpeak pluton west of southern part of Napeequa River, showing rock classification in upper diagram. Average for area east of southern part of Napeequa River and in the northern White Mountains, marked by "+" in lower diagram, is about same as in upper diagram (see fig. 49) 73 CO CO CO CO OO CO Q^ OO OO OO OO OO OO OO OO OO OO OO OO OO OO OO OO 00 00 oo oo oo oo oo oo oo oo CO ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro »-»!- ro ro ro ro ro ro ro ro ro ro a* Average2 CO CO O CD O O O CD Z 3 Standarddev. -j co en en cr» en t i |_> CO » » h- » 1 1 to CO CO CO CO CO to o -a o vo tn 4S> 4*> to CO H- O 3> 4s> to »- 1 t t » CO CO vo »- co »- »- »-+ o en 4* co 4S> CO CO O O I ^> CD 4^k en o 4> ro ro o n » « tn 4>k co ro o vo oo-^« en tn 4> to ro »-* Plot No. -HO -H -H -HXD i -H JO 1 -H 1 -* -H 0 -* -HjO -H -4 -4JOJO i O «- CD O 0 Ql 0 0-»» CD o o o o o OOOOO OOOOO o o 000 OOOOO Rock type cr ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro Specific O -J >J CO -«J ^»J *^4 OO ^*J ^*J ^J 00 OO 00 00 CO ^J CO CO CO » 0 en ro tn O 4S> » » OO ex, tn »-. tn 43k *«i ro ro o co OO CO J VO OO -* oo rsa co -J o vo en o o gravity tn o CO -P» CO CO tn tn en » ' * ! vo O OO CO »- O CO CO O O ro oo tn oo o CO CO CD ro 4i co oo o to ro 3> Potassium o I r* . o 0 O O O O 000 o o o o o o o o OOOOO o o o o I -l feldspar -*» n> tn 43k tn tn en tn tn tn Xi en tn tn tn tn tn en tn tn tn tn tn tn tn tn en tn tn 4* tn tn tn en 4»> tn -j t/» tn tn **J o vo >- CT» ro ro tn co o > * »* en ro co 4* -~J CO oo 4> ro en to Plagioclase O "-« vo vo tn co t~» en *-J oo VO VO CO **J **>J tn ro t en *»J ro vo »- o> co OO vo OO --4 4S» »- CO >-» VO CO rt- 0 3- >- ro ro >- -* ro ro ro >- »- |_> K- > 1 H- ro c o *"«J ro *- en 0 *-J ro tn tn en co ro co o ro vo vo VO Crt co *»J OO en tn ^l vo O 4s. to Quartz vo * ! 43k CO CO co « -» -i en *^J tn n 4* ro ro co ->-J ro ro n co »- Sphene ro to Ql a^ r* Others -1 -»-»-! -» n >- n en ro -i n i en » » n n i B 3 3333 3 3 o> o» o» 3 3 3 0> 3 O» Ql «O D* VO to a* a* QI 3 to QI at QI 3 >.^^_x-a -o -a ... -o » -a -o . -a . -a -a ^^ . «-o T3 "-^ Q| Q| Ql w Q| Ql . 13 -0 -S-S-S-S o -a T3 Ql Ql . * ~a ^-'XJ ' Ql . "^"3 3 3 3 TENPEAK PLJLJTON- White Mtns area 20 I/ K-FELDSPAR 10 PLAGIOCLASE Figure 49.--Proportions of modal minerals of the area of the Tenpeak pluton east of the southern part of Napeequa River and in the northern White Mountains (White Mountains pluton of Cater and Crowder, 1967), showing rock classification in upper diagram. Average for area to west, marked by M+M in lower diagram, is about same as in upper diagram (see fig. 48). 75 CO J> CO CO CO CO CO CO CO CO CO CO CO ro ro ro ro ro ro ro ro i ' i Ol Ol fO er> er> -n er> -n z 3 3 -» i cn 4a» » ro t-* CO 1 CO CO 0 T^ O. D» co ^> ^» ro I * cr» ^» ^» co co Ol VO J> 3> O J» VO CO n> Q. QL ^si cn cn ja> co ro i-» Plot No. < (D Ol cr o O o o o O o O o o Rock type fD -H -t» -h -t» -h -»» -t» i » ro ro ro ro ro ro ro ro ro ro cn CD 0 -J 3 ^sj ^sj ^sj CO OO "^J ^sj CO ^sj Specific CO CO gravity 1 CO -C» ^cSS^ £ O CO CO -O. VO 1 3 0 1 » ** ro Potassium Q. 0 O O O o o o 4» fD cn ^si 1 » CO O feldspar T Crt O 3 ^"^ cn -t* cn cn cn cn cn cn cn cn cn CO CO cn cn ^sj po cn co Ja. vo O ja. rt- O Plagioclase 3- vo vo ja. cn o t-1 i vo i CO CO J ro c 3 < fl> » » ro i-* «- i-* i » ro i » i ro cn ja. cn o vo i-* O ja, ** ^J vo O Quartz 3 -0 O cn vo *» co cn cn CD CO VO O Cn "m ? Ol O 7?- ro CO ja. ro ro co co co i ro co co vo o co co co cr» *» ro cn ro CO 4a> Total TJ rt- cn vo ^sj o ro co co ro co co ro ^J mafics c r»- 01 0 3 i » i » i » i » i i 3 Q. cn vo vo cn CO CO 033-vo ro Biotite >j cn ~J CO co ja. cn CO vo o \f CO «-» rf rf r* 0 CO P" ja, K-. vo « co Fe-Ti oxides -s (/> Ol co cn CO CO ~vl CO ^J VO Sphene 3 i <-» «-» r^- t« r* * rt- rt- ro -i -1-1 ro ~n Others 3 3 3 01 QI Oi 3 3 3 Oi . ^ T3 T3 Ol O* «IH^ « Q, ^_, T3 T3 3 3 -o N I20?45' . ^ I. \VCopper x \ APeok vCVl\\lS^^SEVENFINGERED JACK l\i^\W'and ENTIAT PLUTONS -48° 10' \i\v\/jk.^V *' ' Fernow + -F^v^eve nf j ngered^C^.--- ^i^^ ^ Spectacle Figure 50.--Geologic sketch map of the Seven-fingered Jack and Entiat plutons, showing approximate sample sites. From mapping by Cater and Crowder (1967) and Cater and Wright (1967). Plutons extend farther southeast. 77 SEVEN-FINGERED JACK and ENTIAT PLUTONS K-FELDSPAR »° PLAGIOCLASE r~ 30 QUARTZ FELDSPARS Figure 51.--Proportions of modal minerals of samples from the Seven-fingered Jack and Entiat plutons, showing rock classification in upper diagram. Cater 1 s (1981, p. 30) average shown by "+" in upper diagram. 78 Table 16.--Modes (volume percent) and specific gravities of samples from the Seven-fingered Jack and Entiat plutons -a Q. U Potassium Plagioclas Hornblende X o feldspar t. 0> 81F282A I TO 2.735 .8 62.6 22.4 14.2 8.4 .9 2.5 .9 .1 .7 .7 (sec.ap) 81F283A 2 QDf 2.762 .4 60.5 10.4 28.6 0 10.4 1.4 12.1 .8 0 3.9 (sec.c) 81N154A 3 TO 2.756 .3 59.2 17.9 22.6 1.9 6.7 2.6 9.4 1.0 .6 .4 (sec, p) 82F37A 4 QDf 2.823 .1 61.3 9.6 29.0 12.0 14.1 1.3 .8 .8 .1 tr (ap) 82G30A 5 TOf 2.798 .1 46.8 15.5 37.6 7.1 25.9 2.5 1.2 .9 0 .1 (P) 82F35A TOf 2.668 .5 67.7 29.4 2.4 s 0 s tr s tr s (m.ap.al) Average 2.757 .4 59.7 17.5 22.4 5.9 11.6 2.1 4.9 .7 .3 1.0 Standard dev .054 .3 7.0 7.5 12.5 4.9 9.4 .7 5.4 .4 .3 1.6 79 -48°I5' Figure 52.--Geologic sketch map of the Hoi den Lake pluton, showing approximate sample sites. In part, from mapping by Cater and Crowder (196J). 80 r v\ TONALITE HOLDEN LAKE PLUTON QUARTZ DIORITE/ QUARTZ 6ABBRO 05 C)IORITE/ 6ABBRO V V K-FELDSPAR '0 PLAGIOCLASE QUARTZ Figure 53.--Proportions of modal minerals of samples from the Hoi den Lake pluton, showing rock classification 1n upper diagram. 81 c/> :> CO CO CO CD CO C/J r* < ro ro - - t-* o* Q» m ^1 *TI ^1 ^1 ^1 z 3 3 -f cn cn isj isj isj o -o ex o* **J cn cn cn cn ' D» VQ fl> -f n> 3> 3> co ex ex Cn 4* CO IS) I-* n> Plot No. -H Oi * Rock type cr CD f» CD CD CD n> i ISJ ISJ ISJ IS) IS) ISJ Specific ^4 O CD ^4 CO CO CO CO CO ISJ ^4 cn »*j o » gravity 1 vo cn cn »- o cn co 1 0 Potassium ex I r* o o o o I -i CO feldspar i cn ^4 -^ cn cn cn < »-* cn 0 ^4 4* O CO O Plagioclase -h O ISJ cn 4k cu cn 4k -f C O 3 3 n> t 4k cn cn cn -^4 4k rfO Quartz zy (& VO ^"*J m -i 4k cn »- IS) IS) o 00 3: n> ISJ »- IS) CO IS) CO 0 3 CD *-J Total rf cn cn 4k co cn ex t O i-> O Cn VO 4k mafics n> 3 O» r- ex »-* -» IS) IS) CO Biotite o* co cn O - cn - is) 75- «/» -o o i i H- IS) IS) IS) _j _». 0 CD IS) CD CO O VO Hornblende C -h O VO cn cn 4k co is) rf -« 0 0 t . ua-» 4k isj O O O rf Pyroxene Oi -J 4» CO -I 4k *. rf ISJ I-* 4k i-* <^^ Chlorite O cn vo vo cn o trt O -h IS) ISJ is> co cn Fe_ti oxides vt O 4k ^4 cn o co cn o* 3o O O cn t r*-i l>~ Others ro ^ _ , ^ trt (/) ~O (/) o> *» O Q» « -a T3- V v V V RIDDLE PEAKS V -48° 10' BEARCAT- \ V \ » ^ ^.v SEVEN-FINGERED gneiss and sPLUTONS O^ N> DUMBELL ^gneiss PLUTONS RDINAL PEAK PLUTON Figure 54.--Geologic sketch map of northern part of the Cardinal Peak pluton, showing approximate sample sites. From mapping of Cater and Crowder (1967) and Cater and Wright (1967, and includes areas they mapped separately as contact complexes. 83 CARDINAL PEAK PLUTON V V -K-FELDSPAR 10 PLAGIOCLASE 30 20 K> QUARTZ FELDSPARS Figure 55.--Proportions of modal minerals of samples from the Cardinal Peak pluton, showing rock classification 1n upper diagram. H+" in upper diagram marks average of Cater 1 s (1982, p. 51) modes from nearly the entire pluton. 84 OOOOOO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO c\jc\jr\> c\jrv>c\jOO OOOOINJ rororororo Q* Average2 coocr> oooara: arzaricco cooc^-n-n Z 3 dev.Standard vo^k^ -p» co co rv> rv> c\j vo *»J *^J t -p» co -f* ^> p -o^ 3> ro o oo -^ -* ocncncn»-« ooovooo*>J i 3>3> 3>3>3>O>O vO3><~)OO3> 3>3>3>3>J> ro 00 3> J> o> en *» co r\> » Plot No. l X3 « «- O CO Potassium o^ i-m» . OO rfO« O OOOO. . OO« O ^.~t O -P» en -j .c* en vo vo feldspar «j> eri OOO>**J *sl O>cno> CT» CT» CT» CT» *-! *JO>O>O>"^J O> -vl ^>rorv> ^k co vo rv> Orovoi >o roo»*^o»r\» ... . 3 ...... Plagioclase -so -P» 09 CD >o co rv> 4* co en o> O o> en vo en co i o c ' co ro»-* r\> ro r\> ro m VO £» CO -P» en to rocno eneno>o>ro roenroroco Quartz ^^ - O* rovovo o> oo 4* i c\j c\j o> cr» co *-! cr» » (D (D 0 0 00 ' rv> co rv> co r\> r\> co ro en «- *sl o> co OO-P»»»J *» r\> -f* ro cr» co**Jvo*^Jvo Total * 3 ... . 3 ...... 4k ro o»«->rv» r\> vooo^i 4»i->coco4k voooooroCO mafics SrC- 3 Of Qi ro en CO *^J O> CO VO Biotite -o~*Q. o1 vo co vl O> *» CO c\j O r» v* A » t * ^78 -J CO ^1 »- OO3 3O«^33 3333O O- O Hornblende -o 2. ro **J ro co -H C -« «-» o i r» «/»r*rt- «/»Ort-r»-O OOOO* OOOO Sphene | i -» -IT -I "1 >-* t-' o^ 1 r* cf v> tf> pt-r-^pt-r*-*" rt-pt-rt-rt-* r-t- r* Others n> -» 1-11-1 1111l\»U»1CJli-«1 Cu 3 Q* Q*O O T3 » « '^"^' '-0 3 3 *~^ £8!^ JORJ>A!ii .>0s^v\ ^stt \y^K * /x, < -i%**'+* X 7 / \^V\V5CRI5T\ V - 48°20 V V^V^ Figure 56.--Geologic sketch map of the Mt. Chaval pluton, showing approximate sample sites. In large part, from Boak (1977). 86 MOUNT 17 CHAVAL PLUTON GRANODIORITE 15 10 14 vQUARTZ \DIORITE> vQUARTZ .GABBRO 13, DIORITE/ GABBRO V V V K-FELDSPAR 10 PLAGIOCLASE r \ L _V-___i.__i _ \. -._!__ tO K> QUARTZ Figure 57.--Proportions of modal minerals In samples from the Mount Chaval piuton, showing rock classification in upper diagram. 87 CO OO CO CO CO oo oo oo oo oo oo oo oo oo oo CO OO OO OO OO oo oo oo oo oo CO oo CO OO CO CO OO OO OO OO OO CO CO CO CO CO t t-i 0 0 0 o o o o ro O 0 o o o CD O O O CD O O O O O QI -n -n co co 73 ;o ;o 33 r" <~> <~> <~> <-> z r~ 73 ;a yO r a: -n -n -n Z 3 £* -p» CO CO I CO ->J ^»J ->J o -o .& eo --.i -p» cn J* .p. .0 O* OO o> 3> 3> y> o 3> en en co ro ro ro CD o o en -P» en -p» -P» 4k t ' CD *«J cn co en ** »_. 3> 3> j> ca o oo --i en oo j> co 3> co --J ro «> co -^4 -P» tv> i > 3> - vo -*J cn co > j> j» 3> 0 3> > > n> J> 3> co ;> > 3> 3> > > 3> J> > > 3> co 3> > CO 3> CO co ro ro ro ro ro ro ro ro ro t i O IO OO "J O> en .p» co ro - o 10 co *--i en en j^ co ro i O «o co -*J en cn *» eo ro - Plot \\Q. OXDXDXDXD .0 i i -H CD XD XDXDXD CT> jOXDjO O < - » « » » » t ro »- i i t >- ro ro ^| ro \o - «o co *» en *» co ro crt oo co o »- ro ^o oo ro *> co en o vo *» > ro ro - ro en co cn en co en Quartz w c m en en oo co oo CO -P» CO VO *-J -P» o en eo o en oo oo ro en ro -*J en oo - en -j - VO O «> O ro co o *~J o o «N *» CO CO *» -p» en co co co -e* *» ro co co co co ro j^ *. *» *» cn en *» co en en co >- ro Total *» ->-j o ro ro O en en cn cn -p» oo co en -P» -^1 1 -~l V£> > o -c» ^»J ro co vo O en o *J o *» co «o O VO CO WO CO 5 S » ro ro cn ^o ro ro en eo vo u> ro 10 -c» *~J en ro co en co »- ro co t-' o *» -P» O ro oo O - co co cn -P» cn eo co co mafics ^c?^ 00 02. 00 * i » i ^^0, » « CD ro en ~-j 4^ en -p» -C» CD ~J ro en eo - -c» en -P» ro _ «-f 3 to i/» 3 i/» to 03130 C3 . o . . . o O Biotite oT^ ex en -*J ** o t-' CO UD CD ro en ro co en ro en 00 i co ro oo 10 -i -*J co oo cn < "° A A A » ^-S ro co » ro « ro » co co ro -p» CO CO CO ( ! ro - eo ro ro en cn co co -p» en »- i -J CO CO CD CO UD UD CO CD en CD en co ro en en ro en ro -e» en i >- o "i ro en o ro 2SS 33333 33i3> Hornblende *» 10 -c* co o en O en *» *» ro en » «> ro -*j ro en ro -P» o en co en -*j t cn *^J 2*- tv» -^^ t » 5cr° 1 00 ro 10 i vi o O 0 0 O O 1 O . O 0 0 O O O O O O O O o O O 0 0 I O O O O 0 O 0 0 0 Pyroxene ro en CO bo i vS^ CO K- CO >- CO CO ro CO co H-« en s-< < + to o r+ «/» o i vi o 0 0 Epidote -» -» -c» 10 en -j *» co -» en -i -i -^ --j en en - CO i *» ro ro -» ro 10 oo ro ° 3 - » » i fD 3 r*" -t " \o - >- en CO "J -C» »- en ro -o ro co ro ro -^ Chlorite 0 ~° *" «/» 3 c* 3 «/» 3 vi I d- O i"o -t « -I ~J CO co co -P» en -c» i en ro oo H- > ro - CO VO 1 i en -t co ro cn j> co co o = r*-h H- ro >- >- H- » '*"'' O VI VI VI r+ */» V» VI VI 1 VI Fe-Ti oxides -1 1 CO ro --J co oo *» O CO o co en en co ro *» co CO CO en o VO i oo «o vo «o -*j CO *» ro en 3 O i o O «-* r* «-* O W o i «-* o r* O n- 0 0 0 » r+ «-» «-» O o Sphene -»-»-» -i i -i ^i O en ^» en co co *-J -I CO -*J -» en i -i -t n ro cn -vj co n> VI en .p» »-* ro ro CO t ro ro r+ vi r+ VI VI 1 VI «-* c+ «-*«-» r* r+ «-» r* «-» «-» r* «-* Others -I -» 1 -1 -i -» i en -» co -c» en » co en -» -c» -i -» -t -» CO ~t ro i >- en -vj i -c» ro -*J ro -*j -IO IO. "O - - 3t3 03 - - , .-0 - 01 Q| ^ ^^ ^,«^_ ^ 0| **M**W * ** Di DI Qi Oi fD Di «/» "O IQ tO o> o> (/* Di & o - T3 n -o -o a> 3 o> a -a o -a o> -o TD T3 T3 O T3 n> « ^~* o> ^-^ - T3 fD - 'T3 -a n> T> DI n> o » 3 v < v -O ' *""" 3 '"""eu "^ o vi -a 3 -o - n ~~^ X> 0 (/* Ol < < «/» » c« -o 3 - 3 3 x» & « w w -STD Qi TO < v - -o o o 3 x> 3 o -o o 3 -o Table 19.--(Continued)r-*