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Department of Natural Resources, Geoscience and Mines Branch REFERENCES PURPOSE N Open File Illustration ME 2017-002 A detailed (1:10 000 scale) bedrock-mapping project was initiated in 2008 by Bouyx, E., Blaise, J., Brice, D., Degardin, J.M., Goujet, D., Gourvennec, R., Le the Nova Scotia Department of Natural Resources to (1) produce a series of Pre-Carboniferous stratigraphy and structure in the Menn, J., Lardeux, H., Morzadec, P., and Paris, F., 1997. Biostratigraphie et North Grand Pré 1:50 000 scale geological bedrock maps of pre-Carboniferous stratified units in paleobiogeographie du Siluro-Devonien de la zone de Meguma (Nouvelle-Ecosse, Lawrencetown- area, 12 0 5 the (Annapolis and Kings counties), (2) describe and interpret ); Canadian Journal of Earth Sciences, v. 34, p. 1295-1309. C. E. White, D. A. Swanton, and K-L. Scallion the sedimentary, igneous, metamorphic and deformational history, and (3) Keppie, J.D. and Krogh, T.E., 2000. 440 Ma igneous activity in the Meguma Terrane, kilometres comment on the economic potential of the area. This mapping, together with Nova Scotia, Canada: part of the Appalachian overstep sequence; American Journal Starrs Point 12 previous mapping projects (Fig. 2), have resulted in a major revision of the Horton Landing Avonport of Science, v. 300, p. 528-538. Station stratigraphy and tectonic setting of the Meguma terrane (White, 2010a, b). White, C.E., 2010a. Stratigraphy of the Lower Paleozoic Goldenville and Halifax Hortonville Natural Resources 12 groups in the western part of southern Nova Scotia; Atlantic Geology, v. 46, p. We report here results from field mapping completed during the summers of 136-154. Grand Pré Halifax, Nova Scotia Aldershot 2008 and 2009 (White, 2010b) and subsequent follow-up work in 2010 to 2012 White, C.E., 2010b. Pre-Carboniferous bedrock geology of the Annapolis Valley area Port Williams 2017 Avonport (White et al., 2012), and present a preliminary bedrock geology map and a (NTS 21A/14, 15, and 16; 21H/01 and 02), southern Nova Scotia; in Mineral Belcher Street Wolfville proposed stratigraphy for the Annapolis Valley area, southern Nova Scotia Resources Branch, Report of Activities 2009, (ed.) D.R. MacDonald; Nova Scotia Lower Wolfville Brooklyn Street (Figs. 2-4). Department of Natural Resources, Report ME 2010-1, p. 137-155. Brooklyn Corner West Brooklyn 40 White, C.E., Palacios, T., Jensen, S., and Barr, S.M., 2012. Pre-Carboniferous 20 Greenwich 25 x 11 12 x x INTRODUCTION x x x stratigraphy of the Meguma terrane, Nova Scotia, Canada: newCornwallis constraints Square from Kentville 63 Wallbrook x x x 23 x LEGEND micro and trace fossils; Geological Society of America Bulletin, v. 124, p. 1773- x The Meguma terrane is the most outboard and largest tectonic element in the N x x TRIASSIC TO JURASSIC x x x Wolfville Ridge x Melanson sedimentary and volcanic rocks 1792. x x northern Appalachian orogen (Fig. 1). It forms a distinct tectonostratigraphic belt x x 32 40 Coldbrook x x x 41 CCF LATE DEVONIAN TO CARBONIFEROUS x 0 50 x x 7 20 5 70 in southern mainland Nova Scotia and is characterized by a thick sequence of sedimentary rocks x x CCF x x 84 x x x x x km Wolfville LATE CARBONIFEROUS x x x Gaspereau Early Cambrian to Early Ordovician metasandstone and slate of the Goldenville x x x x 65 x 2008/09 granitoid rocks 20 Waterville Cambridge 61 x Benjamin Bridge 14 30 x x xx 11 x x x 6 x x x and Halifax groups. These units are unconformably overlain by slate, quartzite, LATE DEVONIAN 20 x x x x 65 x x x x 20 x x x x x x 10 x x x granitoid rocks 57 x x x x x x 29 x x x x x and volcanic rocks of the Silurian to Early Devonian Rockville Notch Group. Digby 62 x x x ATHOLITH x Highbury x x x x 38 x x 80 x 65 N B x 35 x x x 71 x x AI SILURIAN - EARLY DEVONIAN x 45 x x 69 x x NT Cambridge Station 60 x x x 6 x x 70 78 x x x 18 U x x x x x White Rock x x x x x 1998 O Rockville Notch Group x x x x x x 46 M North Altonx x x x 6 x x Halifax x x x 35 7 x H x x x SILURIAN x x 7 x The Goldenville, Halifax and Rockville Notch groups were deformed and T Gaspereau U 56 x x 7 x x Robinsonx Corner P.E.I. Brenton Pluton 60 x x 48 x O New x x 10 1999 2007 x x S x x x Mountain regionally metamorphosed during the ca. 400-380 Ma Neoacadian Orogeny, and Brunswick x xxx x x x x x 43 68 CAMBRIAN TO x x Forest Hill xx x 60 45 EARLY ORDOVICIAN 3 x were intruded by late syntectonic to post-tectonic ca. 380-373 Ma granitoid rocks x x 20 x x x AVALON TERRANE Halifax Group 45 x x 4 2000 2006 x x 2005 Aylesford South Berwick x of the South Mountain Batholith and related plutons. Unconformably overlying MEGUMA TERRANE Selfridge Corner x 75 x x Stronach Mountain Goldenville Group xx x Berwick West x 59 x 7 x x 20 Scotia 12 x x Yarmouth x 4 x x x 75 the older units are Carboniferous clastic nonmarine and marine carbonate and CCF = Cobequid-Chedabucto Fault x x Halifax x Newtonville x x x Nova x x 28 N 45 Canaan x Prospect 33 x x x x 12 3 evaporite rocks of the Horton and Windsor groups. 0 100 x 5 x Shelburne 2004 Aylesford East x x x 59 x 2001 x x 2 5 8 x km 60 80 x x x Figure 2 x x x Lumsden Damx x 65 South Waterville x x x x x Bishopville 2002 2003 84 x x x x x 5 55 x x 42 88 2 x Windermere x x x The northwestern margin of the Meguma terrane is unconformably overlain by x x 21 61 x x x x 8 x Davison60 Street x North Kingston 60 Casey Corner x x x Auburn x 12 40 x x x 1 x Early Mesozoic sedimentary and volcanic rocks (Fig. 2, 3). x Lloyds x x x x x x x x x x x 1 x x x x x x x 85 x 70 x 11 x x x 80 7 x o 48 65 W o x x x 86 x 50 x x Laurentia and peri-Laurentian elements N 80 x x 85 75 x 60 W x x x x x x x Peck Meadow Corner Greenfield x Rockland x x x 61 x x Exploits/Gander composite terrane Green Acres x x x x South Alton 45 x x x x x x x x x x x x x x x x 68 74 x 36 Kingston terrane x x 80 4 Black River x x 10 NEWFOUNDLAND 18 9 6 1 x x x xx 74 x x x x x x x 77 Brookville/Bras d’Or terrane x x x Sunken x x x x x x 85 x x x 5 70 75 x x Avalon terrane sensu stricto 76 0 100 Factorydale 5 x Lake 59 5 x 3 4 x x x 66 o x 80 Meguma terrane Millville x x x 81 x x xx 48 N xx x x 45°00’ km x 75 x x x 12 60 x Drill holes that intersect Meguma terrane rock types x x 80 x x 88 x x 2 x x x PRINCE x x 10 Ocean floor outcrops of Avalon terrane rock types Melvern Square Kingston 75 x x x x EDWARD St. John’s 80 x x x x 69 11 ISLAND ATLANTIC x 70 x x x Welton Landing 80 10 x 82 x NEW OCEAN x x USA x x CANADA BRUNSWICK x 65 x 7 88 79 x x x x UNITED STATES Cape Breton Morristown 18 x x x x x o x 50 Island 46 N x 3 LEGEND 8 x x Nicholsville x 25 x x 89 x x South Greenwood x x x x x x x TRIASSIC TO xJURASSIC x x x x x x x x x x x x x NOVA x x x x undivided sedimentary and volcanic rocks SCOTIA x x x x x 12 Greenwood 25 x x x x x x x Halifax x x 72 x 3 x x x x x x x x 54 10 x x 200km Wilmot x x x CARBONIFEROUSx x 80 x x x x x x x x 80 x x 10 x x x South Farmington x x 11 x undivided sedimentary rocks MESOZOIC x 89 Ma GENERALIZED STRATIGRAPHIC COLUMN x Boston x x x x Harmony x x x OCEANIC CRUST 80 x Annapolis Valley x 88 Upper Clarence East Tremont 79 2 Tremont x 80 400 LATE DEVONIAN x 79 x x x 54 Middleton x x x x x x xx x 85 x x SOUTH MOUNTAIN BATHOLITH Rockville Notch x 10 x 1 E lst x x black-grey-green slate New Canaan/Torbrook Figure 1 x 72 x 410 Brooklyn Meadowvale x x x 10 undivided granitoid rocks x x F formations x x 80 4 STRUCTURE 75 x x basalt East Arlington x x x Devonian x x Lower Middleton 76 x x x F x x EARLY SILURIAN TO EARLY DEVONIAN Nictaux East black slate Poles to bedding (S ) from the map area define a well developed girdle distribution x 420 0 South Tremont x L F 9 Kentville Formation ROCKVILLE NOTCH GROUP Nictaux x green slate F with a shallow, southwest-plunging fold axis (Fig. 5a), and poles to foliation (S1 ) Clarence East x x x 12 x x NEW CANAAN-TORBROOK FORMATIONS x F x GROUP indicate a near-vertical, northeast-striking axial planar foliation (Fig. 5b). Minor F 78 x 430 1 x x x x x 68 slate, siltstone, and sandstone; minor mafic volcanic rocks x 88 x 75 Lake black siltstone Torbrook Mines x x x x Torbrook East x x x E 9 and limestone; Late Silurian to Early Devonian fossils x White Rock folds are generally upright and typically plunge gently to the southwest (Fig. 5a) 85 68 George

x x Silurian x x 45 x 80 Formation x 7 x 2 qtzite with axial planes parallel to foliation (cf. Fig. 5a, b). The average intersection x x x 62 x 440 ROCKVILLE NOTCH KENTVILLE FORMATION x x 75 x 5 x x green-grey to red-brown slate and siltstone; minor limestone; x x x x lineation (L ) (bedding/foliation) also plunges gently to the southwest (Fig. 5b) sub- x dolostone 1 x x x 73 rhyolite conglomerate 8 locally capped by black slate and siltstone; rare trace fossils; Brickton 70 x x Torbrook x L 6 x x parallel to the minor fold axes. Two sets of kink band are evident. One set of fold Middle to Late Silurian microfossils Nictaux West x Torbrook x x x U-Pb age 442 ± 4 Ma 85 x 3 450 x x x x x 7 x x x x 8 x x 76 x 7 West x x (Keppie and Krogh, 2000) axes is steep with steep northwest-striking kink planes, whereas the other set is WHITE ROCK FORMATION x 73 x 60 x x x xx 78 x quartzite interbedded with conglomerate and siltstone (in the xx Nictaux x 75 x 8 x shallow plunging with near horizontal kink planes (Fig. 5c). 70 65 7 12 x x northeast); quartzite, siltstone, rhyolite, basalt, chert, and minor x x Falls x x M 460 x x 10 x xxx x dolostone and mafic tuff (in the southwest); trace fossils common; x x x x x x x rhyolite at base dated at ca. 442 Ma (U-Pb zircon) 72 x x 3 x x x 74 x 78 x x x x x x 8 x x x 5 x x North Willamston x x x x 85 x 470 x x x x x LATE CAMBRIAN TO EARLY ORDOVICIAN

x 9 x x x

76 Hellgate Falls x x x x

x 85 60 x black x x x 3 x

x x Ordovician HALIFAX GROUP x x

x x F x x x x

Lawrencetown Bloomington x x 10 slate Formation x x 82 x x

x x xx x x x x x x Contoured poles to foliation (n = 352) x 10 30 x 80 x x x HELLGATE FALLS FORMATION x 76 x x x x E x x x x x 480 x x x x x x 80 F Elderkin Bk Formation x x Intersection lineations (n = 98 = ) x x x x x x x dark grey slate and metasiltstone interbedded with meta- x x x x x x x x x x 6 x x x Contour intervals at 1, 3, 5, >7% x x x sandstone; trace fossils common; locally capped by black slate; x x x 10 50 x x black slate F 7 x x GROUP x x commonly bioturbated x x Lumsden Dam Lawrencetown x x x x x x x x 490 x South Williamston x x x x Formation b

x average ELDERKIN BROOK FORMATION

x

x x x

71 x x x x 5 x x L fold axis x

x grey to red-brown slate and metasiltstone; trace fossils

x x

x x x x 3 x

Nictauxx Southx 7 x black slate F Cunard Formation x x locally present; locally bioturbated 7 x x 8 x 81 500 5 East xInglisville x grey slate Tupper Lk Bk Formation x x x F x x LUMSDEN DAM FORMATION

x 78 x M xx x 4

x xxxxx x x x x x x grey metasiltstone and metasandstone interbedded with slate; Inglisville 78 Lumsden Dam Formation x x x xx x 9 x x Church Point xx x x x x x x x tops of metasandstone beds locally contain graptolite fossils x One of the many specimens of the Lake Paul 510 x x x x 68 x Formation West Inglisville x x x x x metasandstone a c x x x Early Ordovician graptolite x Hellgate Falls Formation 8 x x CUNARD FORMATION x x Rhabdinopora flabelliformis x 88 x x A variety of trace fossil average 3 black slate to metasiltstone interbedded with cross-laminated x x x Contoured poles to bedding (n = 568) 68 x x 520 intersection x x x flabelliformis from the top of a fine- assemblages are common in Kink band fold axes (n = 50 = ) metasandstone; locally contains abundant sulphide minerals x x x x lineation x Minor fold axes (n = 60 = ) xxxx Kink planes (n = 50 = X ) x grained metasandstone bed in the this formation including a Cambrian Axial planes (n = 52 = X ) x 61 Type 2 mafic sills (Sil - Dev) x Lumsden Dam Formation. Acritarch possible Cruziana trackway. E GROUP Contour intervals at 1, 3, 5, >7% LATE NEOPROTEROZOIC TO MIDDLE CAMBRIAN x x x Type 1 mafic sills (pre-Sil) x biostratigraphy from this formation Acritarch biostratigraphy has 530 x 71 Figure 5

GOLDENVILLE GOLDENVILLE GROUP (i.e. Veryhachium lairdi, Cymatio- confirmed an Early Ordovician F Fossil with age control after x (Bouyx et al., 1997 and White et al., 2012) x galea deunfii, and a great diversity of age for this formation (White TUPPER LAKE BROOK FORMATION 8 x 7 Cymatiogalea species) indicate a et al., 2012). 540 2 green to grey-green to purple metasiltstone and slate; Middle-Upper Tremadoc age for this Figure 4 minor metasandstone; locally Mn-rich and coticule-bearing 10 formation (White et al., 2012). 5 cm Alpena CHURCH POINT FORMATION 10 1 mainly thickly bedded metasandstone; minor metasiltstone Figure 3 and slate

65°00’

64°30’