1993 Notes on Franklin Diabases - combined from L. Hulbert, R. Rainbird and C.W. Jefferson June 27, 1993. Air Photo # A16330-88 All stations on overlay 3:30 p.m. LH & CWJ traverse to look at gossan 280ø from base camp. 93 JP-10 South end of gabbroic dykes & diatreme complex. SW wall rock is intact laminated oolite & MT (molar tooth) of NRP. NE wall rock is same. Complete complex comprises 10-50 cm vesicular gabbroic dykes bracketting 2-3m thck heterolithic breccia with fragments of grainstone, molar tooth, stromatolites, gabbro and rare quartzarenite (cm to metres in diameter). Matrix of brx is vesicular mafic rock at this end. Fragments are randomly oriented, all carbonate & diabase. Frags of diabase in diabase-matrix of breccia suggest multiple intrusion (also diabase departs from breccia in places). (s) Samples of dyke on west side of breccia: SKETCH 93 JP-10 A - chill material B - medium grained vesicular diabase - inner rim of vesicles pyrite; cores vesicles carbonate C - pyritic vesicles in diabase from core of dyke D - vesicular chilled "diabase" with cm-size sed. fragments - has disseminated sulfide in matrix, also olivine grains - highly fractured and crumbly [P] Photos 93JP1 # 1,2 Larry looking NW at dykes # 3 coarse diabase cutting finer diabase & dolostone # 4,5,6 panorama fits together, shows dykes on west side of breccia walking north, note also dyke on east side of breccia at boundary with grainstone. Cartoon sketch in plan of complex: SKETCH "key" word = keyhole structures 93 JP-11 Followed breccia and dyke ~ 50 to 70 m North to place where orange dolomite and brown rusty pyrite dominate scree, making prominant gossan here, only 5m of breccia and western marginal dyke (not more that 50cm) are preserved/exposed. Pods of semi-massive to disseminated to sparse pyrite are a few to 20 cm in diameter, concentrated in semi-circular zones in the breccia, close to the vesicular dyke. Dyke also still has disseminated pyrite concentrated with carbonate in vesicles. Note also 2-4 cm tan carbonate veinlets networked in dyke and carb vein with slickensides cutting sub-parallel to and within dyke close to breccia. (S) 93 JP-11 a - gabbroic dyke - has disseminated sulfides and is more altered than 93 JP-10 b - mineralized carbonate matrixed carbonate breccia with patches of densely disseminated to massive pyrite. [P] 93 JP1-#9,10 Show orange dolomite breccia with dark massive sulfide patches surrounding eye-shaped 1.5m lense of grey grainstone. Camp in background in 9, Seagull upper left in 10 (LH in lower centre). This is core of gossan, expressed by mainly orange dolomite alteration, orange dolomite is matrix to breccia, no vesicular gabbroid material. Continuing 50 m NW, breccia of dyke and gossan pinch out. But still lineament with minor dolomite, breccia, recessive zone. 93 JP-12 Diabase-gabbro sill to west of where gossan pinches out. Olivine gabbro picrite. Medium grained granular, cumulate texture, pocked appearance of weathered surface. (S) 93 JP-12 of olivive-rich cumulate from near base of sill. 93 JP-13 -(No sample). Smaller dyke (10-20cm?) offset (en-echelon) to east parallel to other one. At north end, dyke + + alteration take sharp bend to east down cliff (not pursued). Could not see junction of either first sill or this one with sill, except weak recessive zone tht is not straignt but could be minor fault/fracture. No station 14 June 28, 1993 - On airphoto A16330-88 (overlay) 93 JP-15A Gulley with vesicular diabase + dolomite + breccia float. Old flagging suggests was sampled by industry. - NO SAMPLE 15B Second vesicular dyke - NO SAMPLE 93 JP-16 Same sill as 93JP12, farther south, across 000ø fault, west-side down ~100 metres. Sill is ~13m thick, cuts oolite & molar tooth dolomite + dolostone rocks. (S) 16A fine-to-medium gained fresh, basal contact zone 0m basal chill - olivine bearing; acicular plagiolase laths S 16B - medium grained olivine gabbro (diabase) 4.5m above base (middle) - coarser grained than 16a, - granular quasi-cumulate to cumulate  - very fresh, more olivine (S) 16C 13m (top of sill) - medium to coarse grained diabase - good ophitic texture, olivine present - curved pyroxene (pigeonite) - rare pyrite specks - looks similar to Mackenzie Diabase (S) 93 JP-17 - 4 metre sill not expected, discontinous about 500-1000m long - fine to medium grained, sample taken midway through sill - olivine bearing diabase; platy plagioclase (S) 93 JP-18 - diabase dyke: poorly exposed in rubble parallel to lineament - 20 cm wide, aphanitic, lots of pieces to sample - vesiculated (5%) - black-greenish black weathered surface (S) 93 JP-19 within NFC Fort Collinson Fm quartzarenites - last sill of day due to intense wind and rain, treacherous scree: LARGE blocks of diabase were falling off! (S) 19A,B - pyritic quartzarenite (Fort Collinson Fm) - white to cream, rusty, medium grained - 10% pyrite cubes (S) 19C - basal chill of sill right at quartzarenite contact (S) 19D - cumulate about 6m up (S) 19E - coarse grained part of sill from top (2 pieces) (S) 19F guess about 20m of sill total. This sample is fine grained uppermost part exposed; black fresh, dark green weathered - excellent chill (S) 93 JP-20 - fine grained gabbro sill, not seen in place but as large angular blocks; looks like sister of sill across stream to east (93 JP-21 H-L) June 29, 1993 - Airphoto A16330-88 (overlay) 93 JP-21 - Dyke mapped previously by RR just E of Camp; in Reynolds Pt Gp, Boot Inlet Fm; 1-4 m thick, anastamosing, strikes ~000Ä 350ø, dips 0-45øE, weakly magnetic. Dyke cuts up through greyÄ tan biostrome of upright finger stromatolite, then nodular shaly dolosiltite with hummocky cross-laminate and planar laminae with cryptic flat-clast intraformational breccia. Dyke is continuous into ~4m sill which continues north, gently dipping into river; sill curves down, dyke-like into recessive meadowÄ forming zone where terminates. Assume this is same sill as at 93JP 20. Dyke is finely chilled at upper and lower contacts and granular-crumbly weathering in centre - could be flowÄ differentiated central zone. SKETCH (S) Samples 93 JP-21 A - lower chill very fine grained - aphanitic; green weathered surface grey fresh surface, no vesicles, no phenocrysts. B - intermediate zone diabase 120cm from top: fine to medium grained; sub-ophitic to ophitic texture; reddish weathering; "typical" diabase. C - middle zone of diabase, greenish brown appearance, weathers to crumbly dark grey granular appearance; friable, resembles cumulate 65% mafics, 35% felsic; olivine minor. D - upper chilled margin grey fresh, dark brown weathered; undulating contact; aphanitic in marginal 2-3cm, then coarsens to very fine grained. Olivine phenocrysts in aphanitic portion easier to see than in vfgr part. E - lower chill 10m SW of A, 10cm above basal contact F - chill against laminated dolosiltite, dark chocolate brown (aphanitic) diabase specks of sulfide in chill & dyke H - the overlying basal chill of the sill has ~1% pyrite G - laminated dolosiltite country rock, has 1mm pyrite blebs?, 3-5% grey dolomitic siltstone - with pyrite, another source ofsulphur I - diabase from top of sill ~0.2m from top, medium grained diabasic to granular texture, very fresh, but olivine not apparent J - diabase 2m from top of sill, cumulate texture, fresh, irregular shaped plagioclase; areas with apparent olivine K - excellent upper chill, very fine grained to aphanitic, dark grey on fresh surface, flinty top cm and perceptible increase in grain size downward. White quenching cracks on top surface. Olivine phenocrysts apparent on glacially polished surface. L - Glassy chill with phenocrysts from upper contact, direct with carbonate. Thermal metamorphic aureole 2-3 mm. 10% - 0.5 mm olivine crystals in aphanitic (trap-like) ground mass of black material. This is relatively rich in phenocrysts compared to other chills. Photographs 93JP1#11 - shows lower chill cutting nodular carbonate laminate 12 - upper chill cutting finger stromatolite 13 - lower chill cutting finger stromatolite - jumping strat. levels 14 - wavy internal contact (or fracture?) between competent marginal zone below and crumbly weathering core above 15 - upper part of dyke merging with sill (Kevin for scale) 16,17 - panorama of anastamosing detail of upper part of dyke 18 - sparry calcite in 10cm patch in sill above dyke join 19 - xenolith in process of being wedged off 20 - small xenolith in dyke 21 - large zenolith in dyke (dolosiltite) 22 - flowers Bugs: looked for fossils also at 93JP21 - found only sole marks and inorganic structures except possibly some by Kevin (S) 93 RAT-2A - Samples of black quartzarenite from base of Nelson Head Fm. Located ~2km N of Noranda Exploration Camp on Willy & Bandit Claims (72ø16'46" 109ø29'58") - Black, possibly pyrobituminous and pyritic quartzarenite - very porous and poorly indurated - occurs at base of Upper Clastic Member (Burns Lake Fm) where it overlies cherty carbonate member (S) 93 RAT-2B same locality as above but containes less black material and is better indurated; ~15-20% disseminated pyrite with some black alteration (S) 93 RAT-4 sample of black carbonaceous shale from ~3m below ?? carbonate - upper clastic contact from DDH 91-m (Noranda) (S) 93 RAT-5 Base of Burns Lake Fm sampled by Rob Rainbird from drill core June 30, 1993 - Airphoto A16131-155 [P] Photos 93JP Roll #1, from air on the way from camp to Kilian Lake. 23 - photo from air of apparent fault offset along river valley looking N from camp site (in air) 24 - photo from air of gossan (93JP10-20) 25,26 - photo from air Minto Inlet red beds & evap. 27-29 - on ground at fjord fuel cache, scenes looking N 30 - Kilian Lake section from E 31 - waterfall (station 93JP22) 32,33 - shaly dolostones beneath sill at waterfall 34,35 - view of E side of Kilian Lake, 2 sills 4&5 SKETCH Station 93 JP-22 - waterfall station - same as R68 - black shales in molar-tooth carbonate at waterfall outlet of Kilian Lake (A) laminated black shale - grey-black color, fissile ("Bakkan-like") (B) shale-dolomite contact - thin black shale portions on top of dolomite - pyrite xls & patches up to 2mm in diameter in this contact shale (C) - mottled pyritic rusty shales Waterfall is diabase sill which is drift covered around waterfall but continues E & W. Station 93 JP-23 - diabase sill, same as at waterfall (a) - weakly mineralized diabase - medium grained, 2-3% disseminated pyrite in 2 cm band with a block in the talus - block has gossan appearance - this diabase is more altered than other diabases examined to date (saussuritized feldspars) - textural types for diabase from talus slope = fine to medium grained diabase and coarse pegmatite types (taxitic) (B)- taxitic diabase medium-coarse grained - elongated pigeonite present - magnetite & ilmenite present Station 93 JP-24 - top part of sill (same as 23) (A) - predom. medium-coarse grained diabase - K-feldspars in interstitial spaces in some samples - hand specimen grey-green in color - pigeonite abundant - pyroxenes ~ 1.5cm in length present - plagioclase is saussuritized - very magnetic (B) - pegmatitic diabase - fresh (for petrography) - gray, hard - feldspars not as altered as (A) - not as coarse as (A) - weak to mod. magnetic Station 93 JP-25 - basal chill of sill (A) - chill (B) - sulfidic dolostone intraformational breccia sulfides only local Station 93JP-26 - grey diabase with sulfide mineralization - medium grained variety - fairly altered, greasy-grey appearance - saussuritized plag. - 1-2% sulfide blebs & fine interstitial sulfides - sulfides = pyrrhotites no chalcopyrite apparent - small Fe-stained or gossan patches are about 0.3m in diameter - this locality has numerous similar Fe-stained patches with pyrrhotite Station 93 JP-27 - gossan in diabase - medium grained - altered - abundant onion skin gossan weathering - disseminated pyrrhotite - 0.5-1.0mm xls. & blebs up to 3mm in diameter - all sulfides appear to be pyrrhotite variety - gossan area 10 X 10 m and numerous patchy areas elsewhere in the vicinity (s) 93 JP-27 A: mineralized sample with blebs & disseminated sulfides B: mineralized sample with blebs & disseminated sulfides C&D: abundant inclusions of dolostone chips in medium grained diabase. All oriented subhorizontally to dipping ~10ø S E: semi-massive sulfides from locality 50m to the east - this is part of a continuous zone of sulfide - 20% sulfide - consists of patches of blebby sulfide & some disseminated Top of blob - appears that this diabase is separated from previous sill by thin dolostone screen - the prev. sill (Stations 22-26) continuous unperturbed across blob to east ~5m above sulfide - walked ~ 200-300m up to East, got out of sulfides - retraced steps to original showing 27 A-E, then continued down hill along west contact of blob - ~100m past #27 station got 3-4m dolostone xenolith with diabase chill against it, sulfides in diabase chill (no sample here) contact appears to zig-zag with diabase apophyses into dolostone. [P] Photos 93JP roll #2: 1,2 show sulfides in nodular dolostone Station 93 JP-28 - close to chill - edge of diabase outcrop - 4m from heaved dolostone outcrop - dolostone occurs as apophyses into diabase (s) 28A "fresh" with disseminated sulfide (s) 28B veinlet with disseminated sulfide - dolostone all heaved but overall in place * dolostone dips 18ø south, not affected by diabase, i.e. diabase appears to have melted its way in * NB * (s) Station 93 JP-29 - rusty pyritic siliceous siltstone - rubble but at source - siltstone cuts under diabase as seen on airphoto (s) Station 93 JP-30 A,B,C, - thin horizontal screen of serpentine marble transects blob - magnetite & serpentine & talc - bright green Station 93 JP-31 - serpentinized diabase from bottom o/c of stock/"blob" [P] 93JP Roll #2: Photo series showing: 3: plug we just sampled (stations 27-31) 4: sill to east, transgressing bedding upward and splitting into 2 sills toward east (away from plug) 5,6: black shales in Wynniatt Formation with orange-weathering (pyritic?) sanstone above and below 7-10: Minto Inlet Formation red (mustone) & white (gypsum) colours 11: big diabase dipping 45ø SE cutting creek that enters Cache Fjord 12: Minto Inlet Formation just W of camp (station 93JP 57) Haws & Ross Section Black Shale Samples from black shale between Aok Formation and arenite of Grassy Bay Formation (S) 93 RAT #81 ~ 5 m above Aok - shale 80 ~ 10 m above Aok - shale 79 ~ 12 m above Aok (~ 1 m below thin sill) - shale 78 - near top of shale between previous sill and thinner sill, ~ 2 m below upper sill less than 10 m from arenite SKETCH July 1, 1993 - CWJ + LH to N. of Kilian Lake, continue sills 6,7,8,9 (s) 93 JP-32 - sill #9 poorly exposed, near-top, apparently hosted by Minto Inlet Fm; sampled by LH. 93 JP-33 - CWJ to base of section R6A. Walked up through a lot of rhythmically laminated grey dolostone with locally abundant molar tooth. Approaching black shale, encountered 6m sill, then 12m orange dolostone with molar tooth & stromatolites, then 30m black shale ~70% exposed in tiny creek. (S) 33A basal chill of sill (S) B middle-upper part of sill (1.5m from top) - altered, ?pyritic?, granophyre? (S) C upper chill (S) 93 JP-33D Black shale, variably rusty, non-calcareous. 2 sets of chip samples one for GSC, one for UNOCAL. Samples grabbed at irregular intervals along the 30 metre thickness. (S) 93 JP-34 - bottom of diabase sill (Baragar #8) - basal chill - very fine grained, grey on fresh surface, light green on weathered - felted quenched ground mass - no sulfides, sampled toppled block (S) 93 JP-35 - fine grained diabase ~2m above base - grey, relatively fresh - some rusty patches in the vicinity (S) 93 JP-36 - olivine diabase ~5m - granular, medium grained, fresh - fresh surface = grey - olive green - pitted weathered surface (S) 93 JP-37 - olivine diabase ~10m - granular texture fresh, quasi-cumulate - relict layering or cryptic layering - ribs 8cm apart - pitted weathered surface (S) 93 JP-38 - olivine diabase ~15m - fresh, medium grained, granular - pitted reddish brown weathered surface (S) 93 JP-39 - same as above ~21m (S) 93 JP-40 - diabase, slightly more altered ~24.5m - plagioclase weakly saussuritized - irregular 0.2 X 0.3m amphibole rich (??) ruggy pockets (S) 93 JP-41 - grano-diabase (gabbro) ~30m - apparent K-spar in matrix - plagioclase looks saussuritized - no olivine - odd patch where cpx is starting to be bladed (S) 93 JP-42 - medium coarse grained diabase & granodiabase ~35m - rel. fresh sample of diabase, yet grano-gabbro is extensively altered (A) diabase (B) grano-diabase - grano-gabbro diabase has coarse clinopyroxene (altered) + kÄ spar in 1-2 cm laths - diabase (oophitic) groundmass well developed (S) 93 JP-43 40m - fine grained diabase, fresh - ol is present - ophitic texture - plag not as altered as @ # 42 but still is chalky (S) 93 JP-44 45m - diabase chill (very fined grained) - 0.10 m below contact - relatively fresh - greenish black fresh surface - top contact chill is contaminated - this chill is from the top of sill #8 (Baragar #8) Sill #7 Traverse (S) 93 JP-45 0m above base of sill #7 of Barager - basal chill - in toppled block from scree - greenish white weathered surface - fresh surface = sugar brown grey brown. - very fresh (S) 93 JP-47 ~10m - fine medium-grained diabase - SOS, fresh - odd bit of joint related alteration in outcrop (S) 93 JP-48 ~15m - diabase - fine to medium-grained, ophitic texture - SOS, relatively fresh (S) 93 JP-49 ~20m - diabase - medium grained but coarser than previous station - relatively fresh (S) 93 JP-50 ~25m - diabase - medium grained, as above but possibly coarser, rel. fresh (S) 93 JP-51 ~30m - coarse grained diabase - large cpx blade and blotches - acicular plag. in places - weakly altered but fresh for this texture variety - pyroxene blades up to 8 mm (S) 93 JP-52 ~35m - coarse grained to very coarse grained diabase - Kspar in matrix - average grain size = 4-6mm - some samples have 3 cm curved blade of cpx (a) normal CG to VCG diabase with qtz & Kspar in matrix (b) as above except with 3cm curved cpx crystals - the sill is definitely becoming more siliceous up section (S) 93 JP-53 ~41m - medium to coarse grained diabase - relativey fresh - cpx is attempting to become blade-like in fashion - most of the outcrop is like this sample except some may be a bit coarser but is more altered. (S) 93 JP-54 ~45m - medium grained diabase - fresh, greyish-green - much finer grained than prev. 3 stations (S) 93 JP-55 ~50m - chilled diabase - top chill of sill of #7 (Kilian Lake area) - very fine grained - sugar brown to grey brown on weathered surface - good chill (clean) - buff brown weathered surface with shrinkage cracks. 93 JP-56 - CWJ + RR on long traverse July 2, 1993 - sill in Jago Bay Fm, Reynolds Pt Group (above Station 19, west of camp) (S) 56A - basal chill - taken from float below talus - hard to find, long search. Rubble blocks from host boiled up Jago Bay lst. (S) 56B - first solid o/c at 6m up - coarse/medium gabbro - diabase (S) 56C - 14m up - olivine cumulate? seems fresh, granular (S) 56D - ~25m up - uppermost outcrop exposed, fine-grained, close to upper chill? Note 56 sill is greenish (altered?) and transected by numerous close-spaced sub-horizontal fractures. Not easy to get fresh sample! 93 JP-57 Minto Inlet canyon cut [P2] #12, 13, 14 overall view: middle carb \upper bedded evap\upper crab\sill [P2] #15-20 details of evaps+mudstones; 21-22 basal chill of diabase. Rob R. also has photo. (S) 57A - basal chill (S) 57B - 15 m up: 3 pieces fit; medium gabbro-diabase (S) 57C - approximate (20m) sill coarse (S) 57D - gypsum July 3, 1993 LH and CWJ to circular structure (explosive breccias) Overlay to Air photo A16132-99. All stations and samples are 93-JP-58. Specific localities are labelled AZ, AAMM on sketch. Most of these localities are breccias and/or gabbro-diabases. Photographs are indicated as [P2] (roll#) and frame #. Samples are indicated by (S). A. Rounded olive green - brown hill in centre of circular structure [P2] #24,25 whole complex from helicopter looking W [P2] # 26 dome on top (flowers in foreground, LH behind) [P2] #27,28 explosive breccia texture on W. Side. Note crude flow differentiation caused size layering of fragments. Blocks range up to 20 cm or more in diameter (LH max in-place 18cm) [P2] # 29 on NW corner bluff of brecciated stromatolitic lst - upside down! Appears to be block in lst breccia. LH in background [P2] # 30 another panorama of whole ring from locality G [P2] # 37 view from station BB showing sharp straight contact of NW side of diabase breccia with dolostone breccia 93 JP-58 - monolithic diabase breccia centre - fragments of F&MG diabase in a fine-grained friable greenish matrix of altered diabase (like rock flour) - diabase fragments range from 1-2mm to 10-18cm and are angular in form - very fragmented and altered matrix - the altered and friable nature of the matrix imparts the distinctive green colour to the outcrop and the sand and gravel character (S) 93 JP-58A1 - fresh sample of diabase xenolith (18cm long) in friable rock matrix of ground diabase (S) 93 JP-58A2 - fine to very fine grained diabase from talus, ~ 3m from contact of diabase with a block (possibly screen) of strom. dolomite. Fine grained material has possible specks of sulfide (pyrite) (S) 93 JP-58A3 - Normal f.g. diabase - now breccia zone type SKETCH - fragments make up 40-45% of outcrop in places (looks like pudding) - assoc. with white breccia matrix are patches of unbrecciated very fine grained material similar to 58A2 on the east side of the breccia centre. (S) 93 JP-58A4 - medium grained diabase assoc. with frags. & rock flour on east side - all fragmental blocks are pyroxene +/- Fe-Fi-oxide rich (S) 93 JP-58A5 - very fine grained (dyke-like material) adjacent to 58A4 - fresh, sucrosic, odd sulfide specks - similar to 58A2 - this very fine grained material is marginal to the brecciated material & may represent the new intruding magma responsible for the brecciation (yes!!) 93 JP-58B - monolithic diabase breccia (pipe) - 8m in diameter - satellite breccia just ENE of A (no sample) 93 JP-58C - monolithic diabase breccia - all fresh & altered samples are anomalously-rich in sulfides (2-3%) 3 plugs together just NE of B (S) 93 JP-58C1 - VFG fresh diabase with disseminated pyrite specks - some of the more altered & vesiculated samples are very rich in sulfides & have pyrite-rich patches associated with vesicules - this is a good example of a fresh unaltered magnetic parental Magma 93 JP-58D - large (15m diam.) plug with fragments of green-gabbroÄ diabase containing abundant magnetite/pyrrhotite - large epidote crystals in veins & pods - diabase plug (no breccia present) - fine grained, very fine grained, pyritic (2-3%) (S) 93 JP-58D1 - fine grained, sugary brown, non-spotted fresh diabase (S) 93 JP-58D2 - fine grained spotted diabase - more altered than D1 - black 1mm specks make up 15% of rock - black specks look like altered olivine - this variety can be vesiculated & contains more pyrite (as cubes on vesicules with chlorite) - some beautiful epidote crystals on joint surface 93 JP-58E - NW-trending trace of small plugs, measuring from NW to SE: 8X8m, 3X3m, 1X1m, 3X8m, 3X3, 2X2m (vesicular fine grained) 2X2m (fine diabase) 10X10m (large medium diabase blocks in float) also a few heaved outcrops of carbonate breccia - diabase plug (no breccia) - same as 58D1 - the more vesiculated & altered material has more sulfide & large pyrite crystals within the vesicules 93 JP-58G - Lower sill that bounds northern & eastern part of complex dips 26øN at location sampled. Thins out & is either discontinuous or partically till covered to east. Diabase sill ~ 22m thick (0m) G1 = chilled margin, 5mm lower baked zone grading up into very fine grained, fresh, grey-brown quenched material (2m) G2 = fresh fine-medium grained olivine diabase (sulf. ~1%) (4m) G3 = fresh olivine-diabase, coarser than G2 & more granular (quasi-cumulate textured) (6m) G4 = fresh olivine-diabase quasi-cum. with 1mm pyrrhotite blebs this is the best sulfide so far, sample a bit more altered than G3 (8m) G5 = same as for G4 (12m) G7 = altered olivine diabase, slightly less sulf. than prev. sample (18m) G10 = medium-coarse grained diabase, sulfide blebs similar to G4 & G5, but sample is coarser grained & more altered (20m) G11 = fine grained fresh diabase, 4m screen of dolostone above & some coarse pockets of diabase as well. Includes grano-diabase, qtz, + Kspar in matrix; malachite spot stains, a few 1-2mm pyrrhotite blebs G12 = fine grained fresh diabase, with coarser diabase pockets some of which contain 1-2mm sulfide blebs. This material cuts through the dolostone screen Note folds in Wynniatt formation to NE side of structure are interpreted from air photo. Bands are visible from air inhelicopter amazingly well, considering solifluction. Top has no exposed chill. Top is 4m screen of dolostone boiled up with green pyroxene - magnetite porphyritic gabbro diabase. (S) 93 JP-58G 12 pyrrhotitic diabase from 4m screen. Overlying sill is much thicker but pinches out quickly to East. No basal chill observed but relatively fine grained. NOT SAMPLED. H. Continuation of G to east and southeast side of complex. Not visited (nor sampled) but from colour and structural position inferred to be same sill. Visual inspection from distance indicates moderate SE dip. I,J. Mafic bodies not visited but mapped from air photos and distant visual inspection. Note bluffs of dolostone breccia between these and H. K,L. Areas with dark albedo, inferred from air photo to be mafic bodies. K (small mound) verified by visual from ground; L may be swamp. M. Gossan developed in calc-silicate altered oolitic dolostone and stromatolite and laminated cherty dolostone. Dip 36ø West. Underlain by vesicular green porphyritic fine grained diabase (later phase?) ~2m zone of blocks, underlain by brown normal diabase. [P3]#3 shows M N,O. Dark brown west dipping? sills of diabase whose colour looks like normal diabase. Not visited. P. Green-brown breccia diabase pod - visually from ground at distance Q. Bluff of dolostone breccia, sort of in-place, dipping ~40ø S. Brecciation looks like in place hydraulic or shock fracturing, preserving gross layering. Fractured basalt (green) mixed with dolostone breccia forms lower (northern) part of bluff - dark greenish grey. [P3]#2 shows detail of basalt/dolostone breccia contact. Southern (upper) part of dolostone is coarse breccia with randomly oriented fragments. Q. Bluff of more dolostone breccia sort of in-place, dipping ~15øS., cut by & invaded in patches by basalt breccia sill. ~2m Sill is offset piano-key-fashion by vertical faults. [P3]#6 shows detail of lower contact and pods, hammer for scale [P3]#7 shows overall view. This is same sill that continues down into canyon to west ([P3]#4&5). R. Large normal diabase sill not be examined in o/c but visually inspected from air and ground. Colour and structural position make it same as S, H and G. Visual estimate of dip 10øSE. S. Bluff overlooking canyon to W is normal diabase sill, fairlyfractured, overlying fairly fractured but intact typical Wynniatt stromatolite & oolitic dolostone. Dips of bedding and sill are both 30-40ø SW. South margin of sill is truncated by E-W, south-side-down fault with brecciated sill and carbonate. Continuation of other sill (T) across river canyon is terminated against the same fault. (S) 93 JP-58S1 - basal chill (S) 93 JP-58S2 - 5m up in same sill [3]#9 shows this sill from N, view looking South. (also see part of T). T. Tabular diabase sill dips ~ 30øSW. Underlain and overlain by pale tan dolostone, truncated to N by E-W fault & breccia [P3]#8,9,11,12 each show part of this U. North side of E-W fault, see green dome assumed to be breccia, truncating this sill. To N still at this locality, second sill thicker, dips ~20øSW, underlain and overlain by Wynniatt dolostone. This sill is continuous across canyon and stream to sill at S. [P3]#10, 11 shows this, taken from station S looking West. Sketch of T and U: (join photos [P3]#8, 9, 10, 11, 12) SKETCH Sketch of West side of Canyon continuing N of U. [P3]#4, 5 Note sill pinches out toward cone centre; note variable dips in Wynniatt across steep faults. SKETCH V. NW elongate green diabase breccia - from air photo and visual inspection from Q. Very straight, sharp southwestern contact with recessive unknown strata. W,X,Y,Z - normal diabase small pods. From airphoto and visual inspection from S. Southwesterly gentle dips interpreted from airphotos. AA Semi-circular large mound of breccia very much like A. Traversed but no samples. BB ENE - WSW elongate breccia and vesicular fine-grained intrusion. Detailed description following is for western end only. Northern contact dips ~60øN. Bedding in skarnified and brecciated dolostone, dips ~50øN. Wynniatt dolostone here has sedimentary intraformationalbreccia also. Magnetite (manganese? also) + pyrite ñ cpy skarn is developed in dolostone at and near contact in pods - rusty. [P2]#36 shows overall view of contact looking N (dips away to N) [P2]#37 shows 58A (see above) [P2]#38, 39 show dyke-skarn contact in more detail. See distinct textural variation including inter-layered coarse and fine vesicular zones. LH notes: intrusive contact of porphyritic diabase with dolostone. The green porphyritic rock is similar to that of 58C with pyroxene & magnetite phenocrysts - good intrusive contact. (S) 93 JP-58BB1 - magnetite sulfide (+ manganese?) skarn developed in carbonate at contact. Note "glassy" diabase cutting across skarn. In highly brecciated zone. (S) 93 JP-58BB2 - sulfide-rich chill margin - very dense, vesiculated, dark green, (malachite present??) - CWJ (S) 93 JP-58BB3 - about 1 metre away from contact toward south, highly vesiculated with calcite amygdules, malachite stain, sugary brown matrix. LH notes: This entire zone is a highly complex intrusive breccia zone with sulfides moving. Carbonates are metamorphosed to good skarn facies relationships & also highly brecciated. (S) 93 JP-58BB4,5 - dolostone breccia « way between BB and E. CC Highly vesiculated to fine grained massive green diabase with magnetite and hornblende phencrysts like A and AA. But not well exposed - just large to small blocks mixed in dolostone talus from above. (S) 93 JP-58CC1 - highly amygdaloidal fine grained green diabase - looks like flour. (S) 93 JP-58CC2 Green fine grained diabase like A. Both texture and alteration vary, local epidote. CC Bluff of in-situ fractured & locally rotated carbonate breccia, preserving gross layering & stratigraphy. This overlies & is north of CC. Dips range from vertical to 65ø NNW. Note 2 small green plugs of breccia 2-4m diameter between CC and G. Between G sample site and here, numerous highly D & disseminated blocks of Wynniat dolostone. West side of CC' & CC are terminated against NW-SE step ?? DD Flat (5ø W-dipping) sill-"normal" from distant visual of airphoto exam. Steam spreads across this. No samplesnor visits. EE,FF Normal sills dip ~10-15ø W-SW. GG Unknown circular feature - needs checking. HH Unknown circular feature - needs checking. II "Flat" sill, normal. JJ Unknown circular feature - soft till covered. KK Circular breccia complex - high mound-like, gabbroÄ dolerite plugs confirmed by helicopter fly-over. LL Flat sill, from airphoto & circular. MM Large dyke dips ~45ø E-NE, crossing river canyon & making water fall. Not visited yet. NN Good breccia complex with dark gabbro-dolerite plugs, sighted by helicopter fly-over by LH & CWJ July 5/93. End of July 3! OO Work on July 5&6 decided that this is sill; has been made to look linear by NNW faults. July 4 coast sill section (Hadley Bay Day) 93 JP-59 Escape Rapids Fm of Glenelg Group - close to base of Fm, lowest possible in Shaler Group. 72ø 6'N 108ø 25'W (S)93 JP-59A ~(0m) - basal chill of sill by the coast - quartzite in FW - above grey mudstone. - fine grained chill, not baked variety (super quench) - sample taken right at contact - phenocrysts of pyroxene (2-3%) A1 - shows sandstone contact & baked lower 3mm of chill & very fine grained chill above. (S)93 JP-59B ~(2m) - medium grained olivine diabase - fresh - 1mm olivine crystals - no sulfides - sub-ophitic texture (S)93 JP-59C ~(12m) - olivine diabase - fresh - 4-5m blades of cpx (black) - diabasic texture - outcrop is crudely columnar, jointed & well sheeted - no sulfide apparent (S)93 JP-59D ~(20m) - olivine diabase - medium grained - no sulfide - fresh (S) 93 JP-59E ~(30m) - SOS (S) 93 JP-59F ~(40m) - olivine diabase - mainly medium grained, also odd pegmatitic patches - this is the highest topographic point available within this sill - survey with Brunton, using 6ø dip inland (S) 59FA - sample of coarse (1-2cm) cpx crystal, interstitial Kspar & quartz within medium grained olivine diabase - minor pyrite (S) 59FB - representatve medium grained olivine-diabase - this station is a bit more altered than 59E - 1 speck of sulfide in olivine diabase End of sill (S) 93 JP-60 - E end of small lake 72ø 04'N/108ø48'W - sill/dyke transects strata which are horizontal. - lower sill of two sills at this locality - Fine to medium grained diabase, equigranular, no sulfide - sample from middle of lower sill which is separated from base of overlying sill by 10-15m of sediments 93 JP-61 Upper sill of pair at east end of lake, same locality as 60. This is the main sill/dyke which appears to transgress subhorizontal bedding in Escape Rapids Formation. Later work suggests this is true sill; defines large fold: north plunging anticline. 93 JP-61 ~(0m) - basal chill of upper sill (S) 61A1 - fine grained variety (non-chilled type) - very phenocryst rich (5-7%) - footwall = siltstone & immature sandstone, seds highly altered - slightly coarser than usual - olivine phenocrysts apparent - clean chill with no sed basal parting included (S) 61A2 - chill sample with baked lower contact & 5mm of sed. parting present - 15ø dip NE (S) 93 JP-61B (~2m) - fresh granular diabase - medium grained, quasi-cumulate - sucrosic, grey brown - this type can give rise to granular friable weathering - also looks the same at 1m level above the chill (S) 93 JP-61C (~10m) - fresh granular diabase (SOS) (S) 93 JP-61D ~(20m) - fine to medium grained granular diabase as before - these rocks are char. granular like fine grained circulate & more feldspathic - also appear to be more OPX-rich? then CPX or olivine (S) 93 JP-61E ~(30m) - SOS (S) 93 JP-61F ~(40m) - SOS (S) 93 JP-61G (~50m) - same as @ 61F (exactly) (S) 93 JP-61H - same sucrosic-granular gabbro-(diabase) that has a noritic appearance - odd pegmatitic patch - this is the highest available level in the sill 93 JP-62 - new sill locality near section RAT 91-1 Twin sills lineament area Lowermost sill in cherty dolostone: Mikkelson Islands Formation 72ø 15' 46" 109ø 01' 57" just south of airphoto A16169-81 (S) 93 JP-62A (~0m) - basal chilled margin - 5-8mm baked lower portion - weakly porphyritic with mafics (2-3%) - footwall = dolostone (laminated) (S) 93 JP-62B (~2m) - medium grained, equigranular, sucrosic diabase, fresh - outcrop is fairly ? as is the whole sill (S) 93 JP-62C (~10m) - medium grained fresh olivine diabase - some of cpx forms equant black xls (S) 93 JP-62D (~22m) - medium grained fresh olivine diabase - dip of sill = 5ø - SOS July 4 - Hadley Bay - Inland sill study 93 JP-63 - new sill - second one up in Mikkelson Islands Fm, Hadley Bay area. 72ø 16' 49"/109ø 08' 36" located on airphoto A16169-81 & 1:250,000 topo. (S) 93 JP-61A (~0m) - basal chill zone - 8mm lower baked zone - grades up into VFG, chill - porphyritic (mafic phase) (2-3%) - grey-green color - footwall = dolostone (S) 93JP-63B (~2m) - diabase - fine-medium grained, fresh - SOS (S) 93 JP-63C (~10m) - diabase - granular - fresh - SOS July 5/93 Kilian Lake sills Air Photo overlay A16131-154 [P3] # 21 shows section from E [P3] # 22, 23 show basal chill above highly serpentinized dolostone at base of sill # 5 (93 JP-64) [P3] # 24 "GSC at risk" view to S with LH at contact with silhouette of diabase column. 93 JP-64 Sill # 5 (Baragar) - different contact relationship than other sills - chill zone contact is an intrusive brecciated skarn zone with anomalous conc. of pyrite & pyrrhotite chill zone samples A-D (S) 64A (0m) - mixture of chilled gabbroic material & vuggy infilling. Gabbroic material has abundant fine grained diss. sulfides (S) 64B (0m) - more skarn-gabbro mixture with sulfides (S) 64C (0m) - chilled diabase sample - FW is more altered & metamorphosed than any other examined sills to date (at least 5-8m aureole) (S) 64D (0m) - like B&C but with more sulfide (S) 93 JP-64E (2m) - fine-medium grained diabase - odd chalcopyrite speck & pyrite assoc. with minor vein - relatively fresh - 0ø dip (S) 93 JP-64F (10m) - medium grained diabase (olivine) - coarser grained than last station - quasi-cumulate (S) 93 JP-64G (23m) - coarser-grained diabase - grano-diabase - G1 = large black blades of cpx & kspar & quartz in matrix - fairly fresh sample yet most samples have a waxy alteration - G2 = numerous Fe sulfide patches - peg. variety starts at 20m level - 5% diss. sulf. & patches in sample - mineralized sample is more altered but sulfide areas are definitely primary magmatic origin (S) 93 JP-64H (30m) - mixture of diabase & granodiabase from this level - excellent fresh sample - HA = olivine diabase - diabase texture - HB = granodiabase - diabase texture (S) 93 JP-64I (36m) - top of sill - mineralized chilled margin with chilled material ranging from basaltic chill to dactic chill - tacific chill looks light grey - pyrrhotite-pyrite blebs in dacite up to 1.5cm in diameter - sulfide linings in vesicules - almost a gossan zone - although the exact upper chill is not exposed this material is closer to the top - the samples were taken from slabs on the talus of platy laminated dolostone that separates the top of this sill from the base of the next overlying one (S) 64IA = most basaltic sill material - green (S) 64IB = basaltic - dacitic material - green (S) 64IC = grey dacific chill with sulfide - min. blebs & vesicule 10% (S) 64ID = grey dacific chill with sulfide - min. blebs & vesicule 10% (S) 64IE = grey dacific chill with sulfide - min. blebs & vesicule 10% end of sill # 93 JP-65 - new sill (Baragar # 4A) - same photo of section as 64. Note - use photos to estimate total thickness of sill because we measured up - faulted sill on S side (S) 65A - porphyritic very fine grained chill ~(0m) - good chill material with abundant (7-9%), plagioclase & mafic phases (cpx?) phenocrysts - plag. pheno up to 1mm on length whereas mafic pheno 1/2 that size - dark greenish-black matrix (S) 65B ~(5m) - olivine diabase - medium grained - brownish-black color & fresh (S) 65C ~(10m) -SOS (S) 65D ~(20m) - olivine diabase - medium grained, fresh - granular, cumulate (S) 93 JP-65E (~30m) - olivine diabase - medium grained - quasi-cumulate, very fresh (S) 93 JP-65F (~40m) - olivine diabase - a bit more plag. than before - quasi-cumulate, fresh (S) 93 JP-65G (~50m) - olivine diabase - SOS, fresh (S) 93 JP-65H (60m) - olivine diabase - SOS - fresh - very pitted & pocked - the dip used for thickness estimate changed from 0ø to 5ø at this locality (S) 93 JP-65I (70m) - olivine diabase - less olivine apparent than at previous locality - granular (S) 93 JP-65J (75m) - olivine diabase is becoming more enriched in blocky black cpx & looks more Fe-rich - probably represents transition from olivine-diabase to pegmatitic diabase (S) 93 JP-65K (80m) - gabbro (coarse grained - medium grained) - new lithology - no olivine apparent - sub-ophitic texture - abundant coarse blocky black cpx, but still not bladed variety with K-spar & quartz - greasy green quartz & feld but not due to alteration (S) 93 JP-65L (85m) - laminated gabbro - medium grained - coarse grained - igneous lamination of plag. laths 6mm x 1mm - intercumulus wedge shaped pyrox between plag. laths - this is the first true cumulate recognized in the field (although the quasi-cumulate look like good cumulate but have to be verified in T.S.) (S) 93 JP-65M (90m) - laminated gabbro - as at 65L (S) 93 JP-65N (95m) - start to get 30 cm pockets of pegmatitc diabase with granophyre scattered throughout outcrop (5-8%) (S) 93 JP-65O (100m) - coarse grained gabbro with peg. gabbro patches - peg. gabbro patches have 2-3 cm cpx crystals - no apprent K-spar or quartz - bulk of outcrop material is still laminated July 6/93 Silver Mountain Traverses Sills in Evaporite sequence - Minto Inlet Fm 93 JP-66 - sill intrudes base of lower carbonate member (NM2), just above lower evaporite [P3] #25, 26, 27, 30 show overall section; #32, 33 shows Jago Bay up to grey & green Minto Inlet. * FEW RED BEDS!!* [P3] #27, 28 show climbing sill in Wynniatt Fm to NW. [P3] # 31 shows LH at basal chill with laminated dolostone See sketch map for location of sections & samples. Overlay to photo # A16330-68. - basal chill zone - in some places chills are good clean non-sulfidic quenched rocks - in other places they are very sulfide-rich (Py & Po) - the lower portions of this sill sequence is alot greener than any previous sills for this level & they look more mafic (olivine?) 66A1 - very fine grained chilled margins, weekly porphyrhic, no sulfides, 60m south along base of some sill with sulfide (66A2 locality) 66A2 - sulfide impregnated chilled diabase - sulfides appear to be both disseminated in the sample and along fractures within with (with the latter predominant) - once excavated it is very rusty and rotten but on surface there is no indication of sulfides - float in talus or talus debris shows oikocrystic cumulate - good cumulate samples, oikocrysts up to 1cm 66A3 - chill with 3mm of footwall baked dolostone & baked 10cm chill (CJ sample) - host is lower carbonate member of Minto Inlet (lower evap. is just below the base of sill & upper evap. is above the sill 93 JP-66B (2m) - olivine diabase, fine - medium grained, brownish-grey - granular, fresh 93 JP-66C (10m) - poikilitic olivine diabase (gabbro) - granular, medium grained - 8-10mm oik. of cpx with included olivine - rather sucrosic outcrop style - photo of poik. rock roll #2 - 32,33 - poikilitic interval is ~ 8-13m from base of sill 93 JP-66D (20m) - olivine diabase (gabbro) - weakly poik. to non-poik. - very olivine-rich - odd speck of chalcopyrite & pyrite in sample - good cumulate - this is the highest point in this lower sill - photo of upper sill & FW sulfate rocks roll 2 - # 34 93 JP-67 - Across fault - top of same sill - see sketch map on overlay to photo A16330-68 - 12m from top or the highest outcrop level of this outcrop - late differentiates - grano-gabbros (S) 67A1 coarse grained - peg. bladed cpx with interstitial quartz & Kspar, odd specks of pyrite (S) 67A2 coarse grained olivine diabase (gabbro); odd local Kspar & quartz patch (less than above) - cpx is black & coarse but not bladed (S) 67A3 coarse grained olivine gabbro with even less Kspar & quartz (S) 93 JP-68A,B - base of middle evaporite number of Minto Inlet. (S) 68A - alabaster gypsum & selenite - interbedded gypsum & mudstones [P3] # 34 shows interbedding [P3] # 35 shows kink folds (related to faults) 93 JP-69 - new sill - part of piano-key faulted diabase that forms peak of hill. Base of sill not exposed but closely constrained as structurally conformable above evaporites. Abundant basal chill blocks heaved. (0m) - basal chill very fine grained, fresh - green siliceous & serp. slickensided basal FW parting to the chill - part of green color may be due to Cu - odd sulf. fracture in some chills but not this sample - very fresh porphyritic - immed. FW = 0.5 - 1.0m of dolostone & this is underlain by evaporites. (S) 69A1 = chill sample (S) 69A2 = chill sample (S) 93 JP-69B (2m) - olivine diabase, fine - medium grained, grey-brown color (S) 93 JP-69C (10m) - olivine diabase (gabbro) - medium grained, abundant olivine - cumulate 93 JP-70 - new locality - but same sill Sub-horizontal, shown on airphoto overlay to A16330-68 - base of this sill is believed to be in 2m below this lower most exposed level - can see carbonate boiled up in talus (S) 70X (0m) - chill taken from talus, chill can be seen in outcrop but too dangerous? - excellent chill - 1-2mm of FW contact - 1cm baked lower chill zone (? with ? of mafics) - grades upward into very fine grained chill - fracture plan (joint) has fine film of sulfide (S) 70A (10m) - olivine diabase - fine grained, granular - fresh, possibly more leuco? (S) 70B (20m) - olivine gabbro - very pocked weathered surface - coarser grained than 70A - medium grained, fresh - pockted from (19-28m) (S) 70C (31m) - olivine gabbro - medium grained - equigranular - not as pocked (S) 70D (40m) - olivine diabase - fine - medium grained - equigranular - SOS - this is highest available point in sill July 7/93 Kilian Formation Sills; positions on overlay to Airphoto A16137-153 and Figure 8 of Open file 2789 Baragar's sill # 2 = our sill # 4a = 93 JP-71, Baragar's sill # 1 = our sill # 3 = 93 JP-72 Same as lower sill in "Between the sills" at Lineament Creek (Jefferson 1985) 93 JP-71 (0m) - lower of pair of sills (# 4a; # 2 of Baragar) - very fine grained aphanitic chills against carbonate - lower 1-2mm of metamorphosed carbonate - 0.8 to 1.0cm of baked lower chill & grades into very fine grained porphyritic chill - grey brown color - plag. & mafic phenocrysts ~ 1mm (6-9%) - specks of pyrite in baked carbonate (S) 71A1 = chills as described above (S) 71A2 = chills as described above but from 30m along strike from A1 A2 has about 1cm of ? carb. as Fa? porphyry (S) 93 JP-71B (2m) - olivine diabase - fine - medium grained, fresh (S) 93 JP-71C (10m) - olivine diabase (gabrro) - medium grained, fresh, diabasic - granular texture - quasi-cumulate (S) 93 JP-71D (20m) - medium grained olivine grabbro - coarser grained than 71C - outcrop is very pocked due to abundant olivine - cumulate (S) 93 JP-71E (30m) - olivine gabbro - medium grained -not as coarse grained as previous and not nearly as pocked outcrop - fresh - dip of 0ø up to here (S) 93 JP-71F (40m) - olivine diabase - not as much olivine as before & not as much pocking - slightly finer grained than previous station - use 5ø southerly dip from here on (S) 93 JP-71G (50m) - gabbro - medium grained, very little olivine, smooth outcrop - more of an ophitic texture & cpx appears darker - most of outcrop has a weak saussuritization of feldspass (S) 93 JP-71H (55m) - gabbro-grano-gabbro - medium to coarse grained - black cpx is starting to get blocky & weakly bladed - can see traces of Kspar & quartz in matrix - relatively fresh - intermediate in composition between gabbro & grano-gabbro (S) 93 JP-71I (60m) - coarse gabbro - very blocky black cpx, fresh - don't see quartz or Kspar - some weak plag. laminae - similar to the laminated gabbro (S) 93 JP-71J (63m) - mixed zone of Fe-rich gabbro with sheets & pockets of graitic residium (S) 71JA - very fine grained gabbro with large up to 1cm blocky cpx - weakly magmatic - cannot see obvious quartz & Kspar in this sample but they have thin sheets of granite > 5-8cm thick ass. with them - up to 2cm curved pyroxene crystals (S) 71JB - sulfide-rich granitic material - medium grained (not that quartz-rich) - 5-6% Py & Cx - granular cpx - some samples are very leached & epidote rich (S) 71JC - granite with bladed cpx (amphibole?) - cpx up to 1.5cm in length - criss-cross texture of cpx with felsic groundmass * the granitic fraction is definitely a differentiate from the FeÄ rich gabbro (S) 93 JP [P3] # 36, 37 show granite patches 1-3m in diameter. Also # 37 in foreground shows 1-2cm-thick aplitic veinlets & sheets both subhorizontal & other angles. [P4] # 1, 2, 3 show curved pyroxenes in close-up. (S) 93 JP-71K (70m) - Fe-rich gabbro - finer grained, very sheeted (4-6") - fairly pronounced igneous lamination - finer grained equivalent of 71JA (S) 93 JP-71L (80m) - Fe-rich gabbro with minor grano-gabbro patches (10%) - most is coarse grained Fe-rich gabbro with little or no Kspar & quartz - it may also be finer grained & laminated with oriented laths of plagioclase - 5-8 mm magnetite xls in places (S) 93 JP-71M (85m) - highly vesiculated diorite-granodiorite with unusual liquid immiscibility features - irregular ovoid, spherical & amoeboid-shaped granitic bodies (Kspar-qtz-pyrox. bodies up to 2" in length - the matrix of these bodies is always highly amygdaloidal, more mafic & finer grained - most granitic bodies are sulfide-rich (6-7%) - looks like granitic liquid immiscibility in which the more granitic material floated through the more dioritic liquid & the globules subsequently started to merge before freezing. (S)M1 = liq. immiscibility feature in dioritic matrix (S)M2 = liq. immiscibility feature in dioritic matrix (S)M3 = liq. immiscibility feature in dioritic matrix (S)M4 = large block for slabbing [P4] # 4 shows plan view of ameboid structures, also note their hollow nature due to ? weathered out calcite? # 5 detail of layering in cross-section showing convex down liquid-immiscibility structures grading up to highly vesicular tops. NB the layer photographed is horizontally continuous and there are several more such layers 20-50cm thick. # 6 shows overall layering. # 7 shows amygdules (S) 93 JP-71N (90m) - top chill - contact with carbonate - metamorphosed carbonate to greenish white - odd little 0.5 - 1.0mm sulfide sphere - excellent chilled margins - weakly porphyritic (pl. & pyx) * vesiculated diorite like at 71M up to this point 93 JP [P4] # 8 shows screaming stromatolites (baked by sill) # 9 shows sill climbing from 65 (Baragar # 4a) to south (Baragar # 2) 93 JP-72 - upper of pair of sills (our # 3; Baragar # 1) just above 93 JP-71, separated by laminated dolostone & thin sill not sampled - 72ø 06' 11"/111ø 38' 50 located on airphoto A16137-153 - Same as upper sill in "between the sills" at Lineament Creek (Jefferson 1985) (S) 72A (0m) - basal chilled margin sample - contact with carbonate (2-3mm) - FW parting = green carbonate (S) 72B (2m) - contact between graded olivine gabbro (diabase) - coarse grained overlain by finer grained material (S) 72C (10m) - very fine grained sucrosic diabase - sugar brown color (S) 72D (20m) - medium grained olivine gabbro - cumulate - very pocked - pocked from 12m to 23m (S) 72E (30m) - coarse grained Fe-rich gabbro - some samples even show Kspar & quartz (S) 72F (40m) - medium grained Fe-rich gabbro - weakly laminated with plag. July 8/93 Sill at top of Nelson Head Fm, Glenelg Bay [P4] # 11-16 scenery, Glenelg Bay [P4] #30 shows this sill above Burns Lake All measured from NE to SW using 0ø dip. Sill dips ~5ø SE. (S) 93 JP-73 ~2 to 3m above base - exact chill contact cannot be seen is close. Quartzite & diabase blocks are mixed across a width of ~5m, therefore very near the contact. (S) 73A - fine grained olivine diabase - fresh equigranular - diabase to granular texture (S) 93 JP-73B (10m) - olivine gabbro - medium grained poikilitic with 1/2 - 1cm oikocrysts with included olivine - diabase to granular texture - very fresh - surface is fairly pocked (S) 93 JP-73C (20m) - olivine gabbro - medium grained granular - fresh like 73B in that it appears to be slightly more feldspathic than other olivine-gabbro at this level - see odd black cpx and blocky partings suggesting the Fe-rich gabbros are close at hand - not quite as pocked as above & odd 1cm pitted area (S) 93 JP-73D (~25m) - ultramafic float (blocks 1/2 to 3/4m) - black to greenish black - two varieties - blocks are angular [P4] # 19 73D1 - shows block from which 73D1 was taken - mottled peridotie greenish black minor intercumulus plag. ~5% - 1.5cm pocked surface due to cpx oikocrysts - fine to medium grained matrix [P4] # 18 73D2 - feldspathic ?? - non-?? variety - 20-25% inter? plag. - fresh olivine, dark greenish black [P4] # 20, 21 73D3 - fresh mottled feldspathic peridotite (picrite) - intercum. layering defined by 0.5 X 1.0 - 2.0cm elongated pocked marks - very fresh (fresher than D1 & D2) - 20-25% plag. - olivine ñ chromite cumulate (S) 93 JP-73E (30m) - olivine gabbro - not as olivine-rich as before - less outcrop pocks - diabase to granular texture (S) 93 JP-73F (40m) - Fe-rich gabbro - has the char. pitting surface reminiscent of the pocked appearance of olivine-rich rocks - more pyrox. & no noticeable olivine - weakly magnetic [P4] # 23, 24 pyroxene cumulate layering with outer GlenelgBay in background (S) 93 JP-73G (50m) - gabbro to Fe-gabbro - not as Fe-rich as prev. sample but ? pitted - diabasic to granular texture, medium grained, fresh (S) 93 JP-73H (60m) - gabbro to Fe gabbro - SOS (S) 93 JP-74 0m - basal chill to a sill assumed to be same as 73 but thinner, and across fault to east. - would be at the base of sample 93 JP-73A - quartzite partings - some red Fe-stain [P4] # 17 - shows compound sill of 74A chill equivalent to 73 # 29 shows detail of quartzite screen between 74 and underlying aphenitic sill which was not sampled (not fresh) [P4] # 25, 26 - view of orange stromatolite capped by shales and sill, with Reynolds Point Formation in distance on far side of Glenelg Bay [P4] # 27, 28 - granogabbro patches in sill ~ 70m (above 73H but not sampled) From Helicopter: [P4] # 31 - orange stromatolite topped by Grassy Bay Formation (NRG) quartzites & sill # 32-34 - sills & faults in NRG on E side of mouth of cache Fiord # 35 - sill pinching out NRG on W side of cacge Fiord # 36 - view looking SE from cache Fiord toward camp, Reynolds Point beneath; Minto Inlet & Wynniatt in background. Note "son of orange stomatolite" is orange marker in Reynolds Point Formation. Sketch of Field Relationships of 73 & 74 in cross section, looking SE: 74: 2 thin sills; fault; 73: 1 thick sill July 11/93 SW of Kilian Lake to look at Kilian Fm - Natkusiak Fm contact. 93 JP-75 - from the air appears as gossannous volcano shape pucturing sill in Kilian Formation, en route from camp to Natkusiak Formation - pyritic vesiculated basalt - looks like explosion breccia pipe matrix material that is extremely vesiculated - some samples have 25% pyrite - the more vesiculated material is more carbonate & sulfideÄ rich - intrudes rusty shale unit & is flaked by medium grained olivine - diabase - the fine grained basaltic material is a grey color on fresh broken surface 93 JP-76 At base of Natkusiak Fm Note: Kilian Fm is faulted and tilted; one of the circular breccia structures is exposed at edge of Natkusiak O/C. The basal Natkusiak breccia fills grabens in the faulted Kilian Fm. Note large trough X-beds in breccia. Series of photos [P5] show the faults & details. - Natkusiak breccia - highly hematitized (S) 76A - gossan zone 4-5m wide - very fine grained diss. sulfides in grey-green non-vesiculated basalt (S) 76B - highly vesiculated scoracious sample by CJ 93 JP-77 - flew north to head of Glenelg Bay, areal mapping to here. Notes on air photos, compiled in Fig. 6 of Open File 2789 - gossan basal contact of diabase sill - FW = Grassy Bay Formation quartzite - intense contact metamorphic aureole with abundant pyrite & chalcopyrite - most of sulfides occur in a granitic melt fraction within the floor - some sulfide in gabbroic fraction (S) 77A - granitic sweat - very fine grained chill material - basaltic material = very fine grained, grey-somewhat siliceous looking - granitic material - amphibole/pyrox. blades up to 2mm - abundant quartz & Kspar in matrix 3-4% sulfide patches (prite and chalcopyrite) (S) 77B - coarse grained granitic material with 6-8% sulfides + surface malachite stains (S) 77C - semi-massive sulfides in fine grained dark green matrix (chilled basalt?) - 35% - 40% sulfide (Py & Cp) - gossan zone 8-10m wide - this locality demonstrates the most intense metamorphism of the floor rocks observed to date 93 JP-75 July 9/93 - Noranda diabase core DDH-VI91-5 - diabase - 8.2 - 36.8m (S) 93 JP-80A1 (8.2-8.3m) - upper chilled margin - contact with HW of cp+py mineralized cherts (S) A2 (8.65-8.70m) - very fine grained chill, equigranular - part of chill margin facies but coarser than A1 (S) A3 (9.16-9.20m) - fine grained diabase - still part of upper chill suite - equigranular (S) A4 (10.3-10.4m) - fresh fine grained olivine diabase - equigranular - grey green color (S) A5 (11.15-11.25m) - fine - medium grained olivine diabase (gabbro) - coarser than prev. sample - mottled? mafic areas - same up to about 11.75m (S) A6 (12.7-12.8m) - olivine diabase, medium grained, fresh - 11.75-13.4 the rock is more diabasic in texture (ophitic - subÄ ophitic) & tends to have weak clotting appearance due to mafic-plag. clots (1cm) (S) A7 (14.15-14.25m) - ophitic olivine gabbro to olivine Fe-gabbro - medium grained, cpx is getting black & blocky odd sporadic felsic clots (S) A8 (16.50-16.60m) - same as above - in matrix see odd Kspar & quartz xls (S) A9 (18.65-18.70m) - pegmatitic: coarse 10cm plag. + acicular cpx clots - bladed cpx xls up to 1cm in length - no apparent quartz or Kspar - sample shows plag. & mafics to be fairly altered - coarse ophitic texture This is surrounded by ophitic olivine gabbro still up to 19.1m. The following A10 - A17 (19.75 - 33.9) are all mottled due to oikocrysts. (S) A10 (19.75-19.85m) - olivine gabbro - non-ophitic - equigranular with oikocrysts - note odd patch of black cpx (S) A11 (21.0-21.10m) - olivine gabbro - mottled spotted cored appearance due to cpx-oikocrysts (cumulate) (S) A12 (23.38-23.48m) - olivine gabbro - SOS cumulate (S) A13 (25.9-26.0m) - olivine gabbro - SOS, cumulate (S) A14 (27.9-28m) - olivine gabbro, fresh - SOS, cumulate (S) A15 (30.1-30.2m) - olivine diabase, SOS (S) A16 (32.2-32.3m) - olivine diabase, SOS (S) A17 (33.3-33.9m) - olivine diabase - mottled SOS - at 33.6 the olivine diabase with the mottled oikocrysts character ends & the rock gets much finer grained (S) A18 (33.7-33.8m) - fine grained olivine diabase - fresh, equigranular - continues up to about 38m (S) A19 (34.8-34.9m) - fine grained olivine diabase - SOS (S) A20 (35.84-35.95m) - fine grained olivine diabase, SOS (S) A21 (36.30-36.35m) - very fine grained chill facies (S) A22 (36.50-36.55m) - very fine grained chill facies (S) A23 (36.7-36.65m) - very fine grained chill facies (S) A24 ~ 36.80 - chill contact (S) 93 JP-80B3 (VIC 91-16 - 105.05-105.20m) - top chill of sill - contact with HW of white quartzite - not as baked near contact as other chill (S) 93 JP-80B4 (VIC 91-16 - 128.1-128.30m) - lower chilled margin - very fine grained - not baked like others - contact with white quartzite (S) 93 JP-80B1 (VIC 91-16 - 34.8-39.9m) - upper chilled margin - contact with greenish-yellow marly looking carbonate - fairly coarse-porphyritic relative to other chills - lower chilled margin coated with same marly material (S) 93 JP-80B2 (VIC 19-16 - 45.3-45.37m) - porphyritic like top - took sample 10cm above base due to fractures and alteration (S) 93 JP-80C (VIC 91-15 - 57.45-.55m) - lower chilled margin contact with sugary dolomite (S) 93 JP-80D (VIC 19-14 - 49.75-49.8m) - lower chilled contact - contact with weakly mineralized carbonate Station 93 JP-80E: VIC 19-18 - 38.6-45.55 - thin sill but some fairly mafic rocks within (S) 93 JP-80 (43.6-43.7m - felspathic pyroxenite) Noranda del34S=20 per mil (sedimentary sulfides). The isotope composition of ancient gyps. dep. will be approx. the composition at of the ocean at the time of sulphate deposits. 2 samples between 10 per mil-15 per mil = Py & Cp 5 samples between 15-20 per mil 11 samples between 20-25 per mil X = all samples = 19.1 per mil All pyrite = 20.4 All cpx = 18.8 sulfides derived from seawater as marine evaporites NWT = 16.5 per mil ñ 2 per mil (Bowen 1988) which is assumed to be the initial isotopic comp. of Victoria Island sulphate. Bowen 1988 - Isotopes on Earth and Series Elsevier Applied Science 697p. Tennantite and pyrobitumen with Victoria Island sulfides Sample notes, Rae Group & Brock Inlier, C.W. Jefferson, 1993 Rae Group Saddleback Hill just west of Coppermine, just south of road gravel quarry in Unit 21 (upper Mikkelson Islands Fm.); July 16/93. Total 35 metres preserved, top glaciated. 90A B chill at base 90B B chilled dykelet cutting 21. sulphidic centre (sampled in rain) 90C fine gr, 2 m above chill 90D 10 m above chill; brown, coarse patches, ?pyrrhotite? 90E 20 m 90F 30 m 30 m dyke at Turner Showing, Rae River, unit 22-23; July 17/93. Also 93RAT-C4: 5 samples for paleomag. 91A finest possible east side - chills both highly altered, this sample somewhat altered 91B freshest possible, centre Sill, est. 100 m stratigraphically above Turner showing, unit 23; July 17/93 92A fine gr, est 1 m above base - gossan here; basal chill not exposed. 92B ~2 m - " 92C ~10 m - near top of exposure, est 15 m sill 92D float est 10-15 m up - rusty pho along veins & disseminated in matrix. Humungous sill on Murray Island; Johansen Bay Area. This is typical of area; Unit 22 and base of 23 intruded by abundant very thick sills - sea of diabase, much thicker than in Mainland Rae Group or on Couper Islands farther southwest. Sills constitute >95% of bedrock in this area, enclose rafts and slivers of units 22 and 23. This site is raft of 22-23 (cherty dolomite-sandstone contact) at north end, east side of island; enclosed both sides by sill down to sea level. R. Rainbird (station 93RAT-J4) has photo of rapidly climbing "basal chill" of sill, view looking SW. These samples provide minimum, thickness of sill because laterally the sill extends probably 30 m below where chill was taken. Sampling done from about 2230 to 0030 as fog closed in. 93A1 "basal" chill - sill climbs fast in steps at 22-23 contact - this chill contact was not analysed but ts sent 93A2 5 cm above A1 from same hand sample; ts & this part was pulverized for analysis. 93B 2 m fine-gr diabase 93C 10 m 93D 20 m 93E 30 m 93F 40 m 93G 50 m 93H 60 m 93I 70 m coarse 93J 80 m very coarse 93K 100 m granogabbro 93L 120 m granogabbro Sill exposed at Escape Rapids on Coppermine River, cutting Rae Group Units 19-20. Distal view across Coppermine River (Photo roll 7 #38) looks like composite sill with basal 1/3 massive, middle 1/3 layered (finely jointed parallel to dip), upper 1/3 massive. South side is faulted, north side down, fault plane dips about 55ø north. Strata and layering in sill dip 10ø northerly. Section sampled on east side of river, in rain and fog. 94A medium gr diabase - at water's edge; must be at least 20 m above chill. 94B 10 m up; granular - check is this olivine cumulate? 94C 20 m; top of massive - just below apparently layered part of sill 94D 30 m; in layered part - layering textural in coarse gabbro 94E 40 m; two pieces; coarse gabbro 94F 50 m; fine grained diabase - from glacially polished top of outcrop, south end. 94G 55? m; top chill with argillite - walked down-dip, north along sill to upper contact; - note thin sill splay above. Ten-metre dyke exposed on east side of river, trends northerly, second 3-m dyke joins on east to form T; curves away to south making J shape. The two dykes are continuous with each other, but seem to cut sill. Rubble obscures contact relationships. Sandstone at exposed dyke contact overlies argillite which forms upper contact of sill 95A B chill 95B centre. Sill\sheet obliquely cutting units 18, 19 (Coppermine River Group, basement of Rae Group). Diabase-gabbro sheet dips ~20ø N at river. Section sampled on east side of river. Poorly exposed, not possible to get base or top chill due to steep slopes. Best place to sample would be by boat on west side, but could not land helicopter there and sill is exposed in vertical cliff into rapids. 96A close to basal chill in block - cpy and malachite (therefore altered) 96B estimated 2 m - med-fine gr 96C ~10 m 96D ~20 m granular, cumulate? 96E ~30 m 96F ~40 m - had to lean over cliff, so not very fresh. 96G est. 60-70 m med-fine gr. - from glaciated smooth outcrop upslope to east. Shaler Group in Brock Inlier Searched long for well exposed sill in Hornaday River; discovered that there is only one sill, located well above canyon in broad upper part, hosted by quartzarenites of Nelson Head Formation (P3/Hq). The sill is subhorizontal, poorly exposed, typically rubbly tops and bottoms. Sample site chosen is shown on overlay to air photo A13782-24. Top of sill (97DEFG) exposed in small cliff by fluvioglacial outwash channel. Base of sill (97ABC) exposed about 300 m to south in low sloping rubbly outcrop - but reasonably fresh! Sill is estimated to be 45 m thick but could not get continuous section. Vertical distance between C & D could be as little as 0 or more than 15 m. 97A Basal chill - from rubbly outcrop 97B 3 m medium diabase - 2 m level is a rubbly bench 97C 10 m fresh medium diabase 97D base of section at little cliff above pond 97E 10 m above D 97F - 20 m above D coarse, weath. - Sample is core of weathered block 97G 25 m above D, top chill Sill at Halcro Point 045ø\15; in P1\Hp = Burns Lake Fm. Note all gabbros in this area are sills, no dykes. 98A1 basal chill - very hackly, fractured, therfore sampled in 2 spots 98A2 basal chill 98B 2 m 98C 10 m 98D 20 m 98E 28 m glacially rounded, fine-grained. Must be close to top chill. Sill at point west of Cape Lyon, in Burns Lake Fm. Just top of sill exposed. 99 top chill. Sill just south of Pearce Point, dips 7ø NE, cutting lower P2/Hct = Mikkelson Islands Formation cherty dolostone. Much thinner (~4 m), pinches to west in next hill; extends to south in to Quaternary cover; may be continuous with the sill at same stratigraphic level exposed in Brock River canyon. Photo P8#12 shows this secion; P8#13 shows next hill to W. 100A basal chill - 100B base of better section to sample (100 m N of 100A), est 2 m above chill. 100C 10 m above chill, med gr - Granular - cumulate? 100D 20 m above chill, coarse - Very crumbly weathered 100E1 30 m above chill, very coarse Corestone from large block 100E2 ?30 - Chip from fresher block nearby - uncert position 100F 40 m medium grained - from continuous section, but appears to intertongue at this level with dolostone to NW. 100G 45 m fine grained - glacialy smoothed approx top of sill exposure here. Northerly trending dyke cutting basinal facies of Orange Stromatolite (Gelenelg Aok) on seacoast. Dyke is about 30 m thick, highly altered especially on west margin (P8#17). 101A B chill on east side 101B core of dyke, coarse gabbro - from large fresh blocks just above surf zone 101C core of dyke, granogabbro - " Sills in top of Jago Bay Fm. of Reynolds Point Group (P4d/Hcu), just below Minto Inlet Formation (P5/Hce); exposed fairly well in abandoned fluvioglacially washed channel on north side of Little Hornaday River. Lower sill is 2 m thick, separated by about 6 m of cherty dolostone from upper sill. 102 upper 1/3 of thin lower sill, freshest possible because base and top all green. 103A basal chill of thicker upper sill; fresh with regard to modern weathering but moderately altered - oxidation state changed, very reddish hematitic appearance. 103B ~30 cm above base, a bit fresher than 103A but still altered because easily broken. Sample preserves part of hematitic weathering rind. 103C 2 m above base 103D 10 m - coarse; big pyx oikocrysts 103E 20 m - coarse 103F 30 m - medium gr 103G 40 m - long horizontal distance from F, using 3ø dip. Sulphidic - Po? 103H ??50 m?? near top chill, sampled across fault so distance uncertain. Top chill of same sill taken at 105. Best exposure in the area of this sill in Minto Inlet Fm. Still very crumbly poorly exposed sill apparently bracketted by beds of lower carbonate unit, Minto Inlet Formation (with reference to section 93RAT??? just to south), although the only exposure at section sampled is sill, and it is essentially within the sulphate evaporite sequence. The tremendous alteration (the entire exposure is greenish tinged) and vesiculation at both top and bottom of this section [P8#24] is reminiscent of but exceeds that of the climbing sill in NE Minto Inlier at station 93JP64 located on west side of Kilian Lake. This station (104) is exposed in paleo-upstream continuation of fluvioglacial channel NE of 103, air photo A12846-104 104A central piece of block from basal fine-grained spheroidal-altered zone - not very fresh!. Assume 2 m above base. 104B 8 m from basal exposure (10 m from basal chill), just above spheroidal zone, but still polyhedral jointed and heterotextural - aphanitic dykelets cut medium-fine grained diabase [P8#25]. Sampled in two pieces as: 104B1 Medium grained part marked for cutting to analyse separately. Sulphides! 104B2 Aphanitic part, porphyritic, marked for cutting to analyse separately. Sulphides! 104C 18 m above basal exposure (20 m from basal chill), abrupt change to this coarse pyroxene oikocryst texture at 1 m above B. Still sulphides, including cpy; still network of hematite veinlets crossing the coarse gabbro. Sample is core of large spheroidally weathering block - nothing really fresh here. 104D 28 m from basal exposure (30 m from basal chill), same as C but even coarser spheroidal pyx oikocrysts .5-.8 cm diameter, in plagioclase giving net texture. 104E 38 m from basal exposure (40 m from basal chill), same as C & D but slightly browner, freshest sample from this section, but still polyhedral jointed and transected by veins. Sample is core of large weathered polyhedral block. 104F 48 m from basal exposure (50 m from basal chill), from just above E to top exposure the sill is again speroidally structured, fine grained to aphanitic, vesicular(?check sample), complexely transected by veins and highly altered. Sample is from basal talus taken on way up - must be from this zone because talus is developed at site where basal chill zone is not exposed; taken because fresher than anything near top of outcrop. P8#26 shows top of sill; view looks easterly; can see Cck unconformity cutting off sill in background (at this section sill is below unconformity) with red carbonate of Minto Inlet Formation above sill on north side, dipping north. 68ø 34' 03.3" / 121ø 04' 35.6". Plotted on air-photo A12916-149. Top of same sill as 103 is exposed in base of stream and upstream tributaries for very large area; extends E, W & N. This section (93RATB7) is one of best exposures of Minto Inlet Formation, but have about 5 m of dolostone of Jago Bay Fm. between sill and sulphate evaporites. 105 fresh top chill Big dyke (>50 m wide); mapped by Cook & Aitken as cutting P5 but actually draped by Cambrian Mount Clark red and tan sandstones. Location marked on 1:250k geochem-geology map. 109A sample close to but not at chill (Chill not exposed because rounded eroded dyke is draped by Cck) - fine diabase. 109B centre of dyke- granogabbro or syenite - check sample. Sill low in P2 (Mikkelson Islands Fm.) near the mouth of Brock River Canyon; at crest of faulted anticline, on north side of Brock River, east side of fault. Base of sill not exposed; dip ~8ø E. Rocks above sill are carbonaceous dolostone (about 5 m) succeeded by tan cherty dolostone. This sill is inferred to be in the lower-middle of P2; re-sampled at 111. P8#28, 29, 30 show this site looking N. Note extensive alteration of sill next to fault; minor gossan developed. Fault and anticline are Phanerozoic. Offset of fault about 30 m; W side down. Same station as 93RATB11. 110A at water level, lowest point; somewhat altered due to proximity to fault 110B 12 m above A, fairly fresh 110C top chill, 22 m above A. Top of sill here comprises about 0.5 m of chill separated by 20 cm carbonate (vein or screen) then more chill beneath grading to fine diabase. Sample taken from chill above screen. Same sill as 110 comes up again in Brock River Canyon several km to east, complete here. Location on air photo A13635-29. Note textural layering, clear in distance but not up close. 111A basal chill - good one! 111B 2m fine diabase 111C 10 m 111D 20 m 111E 30 m 111F 40 m 111G 43 m top chill - abrupt. Only sill found in Boot Inlet Formation in Brock Inlier (none east of Hornaday Lake). Sill tapers to less than 1 m to south; very gradually increasing in thickness toward northeast; terminated buy erosion together with Boot Inlet on north edge of south-plunging broad syncline. This site is at 68ø 57' 29.2" N / 121ø 40' 40.4" W. 112A basal chill 112B 2 m 112C 5 m 112D 10 m - top chill. possible samples from Rob Johnstone - note at Gela Lake Franklin sills offset 50 m E side down across Bathurst Fault.