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...

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LA THESE A ETE MICROFIL MEE TELLE QUE

NOUS L'AVONS REQUE

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THE STRATIGRAPHY ~D DEPOSITIONAL ENVIRONMENT OF THE LOWER ORDOVICIAN BELL ISLAND AND WABANA GROUPS,

CONCEPTION BAY, NEWFOUNDLAND.

by

Michael Joseph Ranger, ESc. ~

A Thesis submitted in partial fulfillment of the requirements for the d~gree of

Master of Science

Department of Geology

Memoria~ University of Newfoundland September 1978

·st.

^John's ·Newi"oundland

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ABSTRACT

The stratigraphy·of the Lower Ordovician Bell Island and Wabana Groups was studied in order to determine their

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deposi.t.ional environments. A proposed depositional model was then used to study the environment of fo~tion of ~he

Wabana .ironstones.

Accessible stratigraphic sections were measure~ in detail and the data compared to documented ex·amples of

modern and ancient environments of a generally similar na(ure.

On the ~asis of this study a modified geological subdivision is proposed. The division of~he succession into two groups is retained and their subdivision into nine formations is suggested.

It appears that sedimentation in the .Bell Island and Wabana Groups was controlled by tidal processes. Two major .environments are represented in the stratas interbedded

sandstones, siltstones and shales interpreted to be a tidal

'flat complex, and massive sandstones interpreted to be an

~·,.}

offshore barrier or tidal bar. Three subenvironments of the tidal flat complex were recogni~ed1 the subtidal ,

intertidal and supratidal.

Coarsening- and ·shoaling-upwards sequences at two locations may be prograding delta cycles, suggesting that the over all environmental control may have been that of a high-destructive, tide-dominated delta system. Paleocurrent

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directions support these interp~etations.

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Provenance studies indicate that the source _terrain was Precambri9n volcanic, plutonic and probably sedimentary rockG that are exposed nearby on the Avalon_Peninsula.

Detrital garnet ^I .muscovite and met amorphic r?ck fragments. may have been deriv~d fr6m a pr~senily:unexposed crystalline

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basement.

The chamosite ooli~es apparently formed as primary precipitates in shallow lagoons and accumulated on tidal bars and tidal flats where th~ were oxidized, possibly to goethite, forming hematite on ~~agenesis. The periodic

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occurrence of ironstones in the str.ata may be . the result of migrating delta ?~tributaries.

A general correlation of the ~/abana iron ores with similar Lower Ordovician deposits of Nova Scotia, North Africa and Europe is known. The sedimentology of the host rocks, where stud~ed, appears to be strikingly similar to that of the Bell. Island and Wabana Groups. I

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. · \ ACKNOWLEDGEMENTS

The writer wishes to express his ~incere gratitude to all thq_se who assisted in the preparation of' this ~he sis.·

Br. R. M. Slatt suggested the thesis project and p~t

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of' the field work was carried out under his .supervision.

The writer is particularly indebted to Dr. N. P. James and Dr. R. K. Ste~ns under whose supervision th"is thesis

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was wri tteri. ·Their encouragement and valuable discussion are gratef~lly acknowledged. The assistance of' the Faculty ·of the Memorial University Geology Department, especially Dr.

A.

F. King, is also grate:fully acknowledged •.

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For their patience and co-operation, thanks are due r to the technical and photographic staff of the Memorial

University Geology Department and the. Calgary office of Gulf Canada Limited.

Field expense support was provided by National Research Council Grants A-9159 to N. P. James and A-839.5 to R •. K., Slatt. A University Fell~wship provided the writer with financial support during this.study.

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TABLE OF CONTENTS CHAPTER

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ACKNOWLEDGEMENTS

.

I I I t t e I t t t t f t t t t t t t " t t t • t t t t t t t I t t t

• f(l .

LIST OF FIGURES ... , ... .

. . . . . . . . . . . . . . . . . . . .

LIST ·oF TABUs •.•..•••••••.• • . • • . • • . . . ·~· . . . . 1 • INTRODUCTION •.• , .•.• , . . . . Purpose of Study .· ... : ... . ' ( ' ...•... , •...

Regional Geology . • . . • . . • . ,• ... • • . . . • . . . • . . • . . • Paleozoic Rocks of the Av·alon Zone •.... , ...

History and Previous Work

...

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2. METHODS t t t t t • t I I I t I t I I t I I I t t t I t t I I t • I t I t t t t I I I t t I t I t t

Field Methods t I I I I I t t I I t I I I t t t I I t I I t I I I I I I t t t t t I

Laboratory Methods

...

3. Sll'RATIGRAPHY I t I I I I t I I t I I t I I t I I t t t t I I t I t I t t I I t I t I I I t

Introduction . . . ( . ...•.. , , •.• , .. . Description of Formations ...••.•.•..

Kellys Island Fot1nation •.••..••••..•.••.•.•..

Beach Foi1Uation ••••••••••• _ . . . • • . • . . . . • • . . . • . . Redmond Formation I t I t I I t t I a I I I t I t I t t I t t '!" t t t t t

Ochre Cove Formation Dominion Formatiqr .•

t I I I I I I I • I I I • • I I I f' • • I • I I I

...

Powers Steps Formation Scotia Formation ...•.•

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... . ...

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Grebes Nest Point Formation _I _I _• _• _' _• _I _I _I _I _I _I _• _• _I _I _I _• Gravel Head· Formation ••.•.•

... ...

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1 1 i 4 6 8

16 16

17

19

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19 22 22

26

27 29

30 ^~

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32 35 37 J9

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CHAPTER ' PAGE

Age of the Strata· , , . . . ; ... , .... . 4. DEPbSITIONAL ENVIRONMENTS . 0., o • • o • • o . o o . o • • • o·· • • • • •

Introduction . . . , . . . · . . . • · .. · ..•.. ·, , ... . Tidal Flat Complex ⁰ ^{• • • 0} 0 • • • • • • • • • • • • • • • • • • • • • • • o

Subtidal Facies ⁰ ^• ⁰ ^{o ; ,} ^{, ,} ^{, • ,}^,o.⁰ ^{• •}

('f: . - ...

^o^o

Intertidal Facies ... ·. ^{o • • •}⁰ ^{• • ,} ^• ^• ^• ^{·, .}^{· / ·}^{• • •}^o

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Lower Sand Flats ... ⁰ • • • • • 0 • • • ~--'• 1 • • • • • • •

.,...,._.. . I

Middle Mixed Flats . , . ·. , ... , . ~...--;---:--:. .· ... . Upper Mud Flat,s , , , , ..• ⁰ • • • • • • • 0 • 0 • • • • • • • • • •

Supratid~l Facies~., ..•... . ~ ..

o••···.

Offshore T{dal Bar Complex , . o• ••• , •••• ••••• : ••••

Offshore to Shoreface Facies ..• •• •••••o•••••;

Foreshore-Beach Facies •.. • • • o • •

,

••o•o•••~o•••.

Supratidal Facies

.. ... ...

Regional Enviro~ent - Evidence for a

40 41 41 . 42 44 45 45 49 57

59 64 66 71 73

De 1 ta . . . . . . ^{o o}^{·• • •} ^•^• ^{• • •}^•^{• • •} ^{• •} ^•^, ^{o •}^' ^{• •}• • o .- • • • o ~ • • • 7 5 Field Evidence ... , . ^o^.^{• ,}• o • • • • o o • • o . o o o • • • ·o 76 Depositional Environment of Little Bell.

Island and Kellys Island Formations •... • o o o • o • 81 Paleocurrent Analysis

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PETROLOGY AND PROVENANCE '

I I t t I 1 I t I I t I I I t I I t I I I I I I I I I

I I I I I I I I I I I I I I I I I t I I I I I I 1 1 1

85

88

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Sandstone Petrology ^{o . o}• • • • • o • • • • • • • • • ,· • • · • • • • • , • o 88

Prodelta Sil;ty Sandstone ^{o •} o o • • • • • • o o • o o . - . o • • • 88 ~--.

Subtidal-Lower Intertidal Sandstone . ^o^o^{o • • o}~ ^• 90

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CHAPTER PAGE

Intertidal· Sandstoneo ... ~.: . . . • _... ~··;·,: ..

-··· 91

Tidal Channel Sandstone . •. :"'· ;··: -~ -~ .. : .. ·. ·:·: ... r .. 94.

~- ~

Offshore Tidal Bar Environment Sandstone .- ...

l 95

Provenance . . . .• . . . ... .. 96 Quartz . . . . • . . . . ,• . . . ·'·· .... ... . ... . 96 Rock Fragments .... , . . . ... , ... _. 97 Metamorphic Rock Fragments . . . • . . . • . . 101 Plutonic Rock Fragments . . • . . . .... 1 01 Sedimentary Rock Fragments . . . ... . .... .. 103

Heavy Minerals 106

~ummary and Interpretation Gf

~r.ovenanc e , , , . , .• , •. , , . . . . • . , ..•.. , .. ...• 106 6. DEPOSITIONAL ENVIRONMENT OF THE IRON ORES · •.•....•.. 111

Facies Relationships . . . • . . . • . . . • • . . . 111 ·1

Environment .of' Formation .. , . . . . • . . . • . . . · .... 116 Phosphatic

Glauconite

Pebble Beds •.•. - .··~·~ • . • • . . . · · • · . ··~···

...

Oolitic Pyri ~e. Beds . . . . Îll ^{• • Ill} ^{• •} ^• Îll^{• • •}Îll^{• • I} ^{• •} • • • • I . , . _

7. DISCUSSION ¹ Î ¹ ¹ ¹ ¹ ¹ Î ¹ ¹ ¹ ¹¹¹ Î ^• Î Î Î Î Î Î Îll¹ Î ¹ Î Î Î Î Î Î ÎllÎ Îll Î Î ¹Î Î¹ ^j,¹ Comparison of' the Bell Island-Wabana.

119 120 123 126

Sediments to Other Tidal Flat Environments . .... 126·

Iron Ores

... ... ..

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Source of the Iron· .•...•.•••..•...••.... 1 JJ Regional Correlation .. With. Other Lower

Ordovician Ironstone Deposits 137

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CHAPTER

8. CONCLUSIONS

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I I I I I I I I I I I

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~FERENCES ... .

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APPENDIX I I I I I I • I I I I I I I f I I

I I I I I I I I I I I I I I I I

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PAGE 14J 146 .156

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LIST OF FIGURES FIGURE

PAGE 1. Index Map '

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A ₂

2. ~YJ>ical coastal cliff expc)sure of the Bell

Island and Wabana Groups . . . , . . . . . . . . . . • • . . . . 3

J.

Stratigraphic section of the Bell Island Group and Wabana Group

I I I I I I " e I I I I I I I I I I I I I I • I I

4a. Septarian nodule horizon

I I I I I I I I I I I I I I I I I I I I I I I I •

4b. Septarian nodules surr.ounded by cone-in-cone

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s~ructure . . . , . . • . . . : . . . , }4

5. Depositional model and idealized stratigraphic

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sequence for·the Bell Isl~d and ~abana

~

^Groups . . . , , • , . . . . . . . . . . 4J 6. Lenticular sandstones with scoured bases . . . 46 7. Current ripples indicating water flow around

the slip face of a megaripple

...

46 8. A sec~ion through the intertidal facies . . . . .. . . 47 9. Herringbone crossbedding in the lower sand

- " flat subfacies • . . . . . . . . . . . . . . . . . . . . . . . . 50 10. Rippled _sa~dstonelenses in_siltstone of the

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'middle mixed, flat subfacies .•.. , . . . . . . . . . • • . . • . 50 11. Flaser,· wavy and lenticular bedding .... ··~ .. . . ~1 12. Mud-draped flaser-bedded sandstone overlain

by starved ripples ... , . • . . . . • . . . · . . . • ~... 51 13. Runzel marks displaying wide variation ~n

size

I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 53

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FIGURE

14. .> ... ~

Fossfl raindrop impt~ssions

PAGE

e • • • ' I ' • I • t I I I I • I I I I I I t 53

15. Runzel marks sup~rimp9sed on ~scoured

interference-rippled surface . . . -... . . . . . 55 16. Rill marks superimposed on an interference-

rippled surface .. , , , . . . • . . . · .. · 55·

56 0

56 17. Inter:f~;rence -rippled surfac,e truncated by scour ..

18. Flattened, double-crested ripples .: . . ~-.. ~·: .• ..•..

Flat bottomed, sand-filled tidal channel

... 58

20, ·Scour-and-fill in the middle mixed flat ^~~

subfacies . . . -. . . , . 58

21. Intense bioturbation in silty shales of the .

upp~r mud :flat subfacies . . . • . . . ₎ ; .. ,,, . . . 60

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22. Mudcracks .. , • . . . ~ .. :· . . . • , ..• , . ,·.... . . 60 2), Banded black shales of the Supratidal facies .. ... 62

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24a. Graded bedding . . . , , . . . · . . . . , . . . . , ~2

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24b.

Mudcracks, in section . . . .. · . : . . . ·· .. ,

j ....

~ 62 Sand-filled major tidal channel .. .... ...•

j...

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25.

26a. Herringbone prossbedding in sand-filled

tidal ch~el . , . . . • . . . ..• . . . • • . . . • . , . . . .... ·

65

26b. Large shale chips forming lag ~eposits

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~ong bedding pl~es

I I I I I I I I I I t I I I I I I I I I I I t I I I I

27. Mega:ippled sandstones of the offshore to

shoreface . facies . . . .. . . . ·· .... . . , . . . , 68

2"8. Trough crossbedding . . . . . . • . . • . . . . . . . . . . . . • . • . . . . . 68 29a. nscribbli~g" grazing traces _·• • • • • • • • • · h •• ~ I' • • • • • . • • 6 9·

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FIGURE PAGE

29b. Ichnofossil of unknown affinity

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JO. Large stylolite surface forming a parting

plane in massive sandstone . . . . . • • . • . . • • . • . . . . 70

31 a. Swash marks . . . ~. . . . . . . . . . . . . . . . . . . . . . . . . 72 J2b. Current crescent . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 J2a. Meandering rill marks on a bedding surface

in the Redmond Formation 74

J2b. Conical rill marks superimposed on swash marks . . . 7u JJ. Shoaling-upwards del ta~c sequence . . . . . . . . . . . . . . . . 78 Ju. Sand-filled channel . . . . . . • . . . . . . . . . . • . . 78

J5. Section at Powers Steps . . . . . . . . . . . . . . . . . . . • • • . . 80

;:r-·-·- - f

J6 • Paleocurrent cro~sbedding direction in the

lower part of the Beach Fornation . . . . . . . . . • . . . . 86 J6b. Paleocurrent crossbedding direction in the

Wabana Group and the upper part of the

Bell Island Gro~ Î Î Î Î ^t ê Î Î Î Î Î ^t Î Î Î ^t Î Î Î Î Î Î Î Î Î Î Î ^t ^t Î 86 37. Fine-grained quartz arenite from the subtidal

zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 ·· 38. Detrital volcanic quartz fragment . . . • . . • . . • . , . , 9J 39a. Detrital acid '\Olcanic fragment

J9b. Detrital acid volcanic fragment

I I I I I I I I I I I I I I I I I I

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99 99 40. Detrital porphyritic volcanic fragment . . . 100

41. Spheruli tic rhyolite fragment

...

100 42. Stretched metamorphic (gneissic) rock

fragment

... .

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ix

FIGURE PAGE

4Ja. Micrographic texture in :plutonic rock ^~) fragment . . . . .. . . ... . . 104 4Jb. Granophyric texture in pl ut onic r ock

fragment . . . .... . . • . . . , . . . . . . 104 44. Detrit al rnetaquartzi te fragment . . . . . . . . . . . . 105 45. Fining-upwards intertidal sequences . . . . . . . . 112 46. Large -scale, f aint crossbedding in the Scotia

Ore Bed . • . . . . . . . . • . • . . . . . . . . . . . . . . . • • 114 47. Glaucon i te forming as an alterat ion of biotite

between cllfb.vage planes Î ^t Î ^t Î Î Î Î Î ^t Î Î Î Î Î Î ⁰ Î Î Î Î Î Î ¹ 122

48. ^Pyritê ^Memb^{er th}ⁱ^{n s}êc^tîon

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49. Pyrite coated shale pebble in the Pyrite Member 124 SO. Rippled washout structure in an apparently

heavily grazed sandstone surface ... .. . . 1 JS

51. Suggested mechanism for the fonnation and accu-

mulation of the Wabana-Be l l Island ironstones 1 J6

52. Distribut ion map of the Lowe~ Ordovj cian

ironstone environments . . . . 1 J9

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LIST OF TABLES

TABLE PAGE

1. Table of Forma-tions Î ^• Î Î ^t Î Î Î ô Î Î Î Î Î ^t Î ^1,.,^t Î Î Î Î ÎÎ ^t Î Î Î Î Î Î Î 20 2. Depositional Environments of the Bell Island

and Wabana Groups , • . • . . . • . . . • . . . . . 84

J. Sandstone Thin Section Petrology . . . . . . . . . . 89 4. Rock Fragments

5. Heavy Mineral Grain Mounts . . . . , . . . , ... , . . . . ' .

6. Comparison of sedimentary structures in the Lower Ordovician Bell Island and Wabana Groups with' other documented intertidal sediments of

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Paleozoic age . . . . . . . . . . . . . • . . . . . . . . • . 127 .

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1

CHAPTER 1

INTRODUCTION

A sequence of sedimentary rocks and iron ores ' of

Lower Ordovician age are exposed on three islands in

Conception Bay, southeast Newfoundland (Fig. 1). The lower part of this sequehce, the Bell Island Group (Rose, 1952), crops out on Kellys Island, Little Bell Island and Bell

Island; the upper part of the sequence crops out only on Bell Island. Bell Island is approximately 4J square kilometres in area anQ ,is the largest and only inhabited island of the ' three. F:lve ironstone beds are exposed on Bell Island and

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threehave been economically exploited, supportihg a

mining industry for over 70 years. Operations ceased in 1966.

The stratigraphic sequence is well exposed along

narrow gravel beaches at the base of high coastal cliffs. (Fig.

2). On Bell Island, the majority of these exposures are Within reasonable walking distance from a road. Other isolated

coves, as well as Kellys Island and Little Bell Island-, are accessible only by boat. Apart from the coastal cliffs, surface outcrops are of limited extent and are not well exposed·.

Purpose of Study

This study has a threefold objective1 (a) because no formal subdivision of the entire Lower Ordovician stratigraphic section of Conception Bay exists, the first objective will be to describe and subdivide the stratigraphy in a

-- manner that conforms to formal rules of stratigraphic

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CONCEPTION

BAY

Little Bell Island~

Kellys/!9 Island

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FIGURE 1 INDEX MAP

f)

^Baccalieu

i.)

^Island

Ordovician

Cambrian 0 2 4 mi

I ^{1 '}¹t' 1 'a •'

0 2 4 6 km

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3 FIGURE 2. Typical coastal c l i f f exposure of the Bell Island and Wabana Groups at "The Bell", Bell Island. Note trees for scale;

cliff is approximately 65 metres high.

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nomenclature: (b) to expand the interpretation of the depooi tional.

environment of the Bell Island and Wabana Groups and..attempt to relate this environment to ree;ional geology; (c) to recognize which aspects of the depositional enviromnent favoured the formation of the iron ore beds.

Regional Geology

The Island of Newfoundl9nd constitutes the northeast- ern limit of the Appalachian Mountain System and, on a first order scale, has three principal stratigraphic-tectonic belts which trend in a northeasterly direction (Williams, 1964: Kay, 1967). The middle unit. the central moo·ile belt, comJlr.ises deformed Paleozoic geosynclinal sediments and volcanics. It is bounded on the northwest and southeast by Precambrian terrains that were gently subsiding stable

elements during the Lower Paleozoic, upon which shelf deposits were accumulating (Williams, Kennedy and Neale, 1972).

The northwestern Precambrian belt consists of

gneisses, schists and granites of the Long Range Mountains in western Newfoundland. The lithology and structure indicate that these rocks are Grenvillian inliers o:f the Canadian Shield (Clifford and Baird, 1962). The overlying shallow- water shelf sediments, dominantly carbonates of Cambrian to Lower Ordovician age, are typical of the lower Paleozoic continental margin whose development is recognized along the

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entire western margin of the Appalachians. The southeastern Precambrian belt or "Avalon Zone" (Williams, Kennedy and

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Neale, 1972), on the other hand, co~sists of Precarr.brian rocks that are well exposed in Newfoundland, but poorly

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represe~ted in the eastern part Jf the Un1ted tates

Appalachia~ system. The l ithologies consist of little- defonned Late Precambrian s,ediments, volcanics and plutonic r ocks.

On the Avalon Peninsula, the Pre cam brian rocks can be 1

placed into three broad divi sions. These are reviewed by McCartney (1967) and consist of (a) acid to mafic volcanics of the Harbour Main Group, (b) marine volcanic sediments and tuffs of the Conception Group and (c) marine and alluvisl volcanic sediments of.the Cabot and Hodgewater Groups. The geology has been interpreted by Hughes and Bruckner (1971) as the late Precambrian development of a volcanic island complex (Harbour Main and Conception Groups) and the post-vol canic phase of erosion and sedimentation

(Cabot and Hodgewater Groups). The Holyrood Plutonic Series, consisting mainly of quartz monzonite and grani t·e, intrudes the Harbour Main volcanics. I t is considered by Hughes and Bruckner (1971) to be penecontemporaneous with the Harbour Main and Conception Groups.

Papezik (1972) has suggested that the geology could be interpreted instead as alkalic continental volcanism related to block faulting of a late Precambrian continental platfonn.

Overlying the Hodgewater Group either conformably or unconformably at a slight angle (McCartney, 1967) ^{is from}

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6 to 150 metres of white unfossiliferous quartzite of the Random Formation, either latest Hadrynian or earliest Cambrian in age. McCartney (1967) considers the Random quartzite to be reworked conti~ental sediments along the shoreline of an advancing Cambrian sea. The Random quartzite does not occur around Conception Bay and Cc;mbrian beds here lie with angular unconfonni ty directly upon the Harbour Main volcanics and the Holyrood Plutonic Series. At Manuels, near the Conception Bay coast just south of Bell Island (Fig~ 1), the

basal Cambrian is a conglomerate, six metres thick, consisting of coarse angular to subrounded clasts (Rose, 1952).

Paleozoic R@cks of the Avalon Zone

The Cambrian rocks of the Avalon Zone occur in widely scattered outcrops, but their lithological sequences are readily correl~table between outcrops (Hutchinson, 1962).

Hutchinson (1962) estimated the maximum thickness of the Cambrian deposits to be up to 1300 metres. They consist mostly of shale with some shaly limestone and siltstone.

There are a number of thin limestone beds near the base of the Lower Cambrian, and thin subeconomic manganiferous beds in the Middle Cambrian. The Upper Cambrian becomes gradually sandier towards the top (Hutchinson, 1962).

Three major periods of deposition during the Lower, Middle and Upper Cambrian Epochs are recognized and i t is apparent from isopach maps that southeastern Newfoundland

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was a broad, in"'cerni ttently subsiding basin whose axis trended just eas"'c of n~orth during tf1e Cambrian times, with probable shorelines to the east and west (Hutchinsor., 1962).

Good fossil control is provided by trilobites which be long to the North Atla.'"ltic province (Walcott, 1888;

Howell, 1925; Hutchinson, 1956: Fletcher, 1972).

The Lower Ordovician Bell Island and Wabana Groups consist of at least 1500 metresJof interbedded micaceous sandstones, siltstones and shales. The Cambro-Ordovician contact probably occurs somewhere under the waters of

Conception Bay between Kellys Island and the coast (Fig. 1).

Both sequences dip gently 8 to 10° to the north-northwest suggesting a conformable contact (Rose, 1952). Thus, as Hutchinson (1962) points out, the depositional basin

controlling sedimentation in earliest Cambrian times _II

apparently persisted into the Lower Or.dovician.

The only other Ordovician rocks of the Avalon Zone are exposed west of TTinity Bay, partly on Random Island

(Christie, 1950). These sediments are mostly grey and black shales of the Clarenville Group believed to be of lowermost Ordovician (Jenness, 196); Dean, 1970). They are possibly correlative with unexposed rocks below Conception Bay between Manuels and Kellys Island (McCartney, 1967).

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History and Previous Work

The native people of Newfoundland, the Beothuck Indians, were tradi tiorially lrnown as the "Red Indians" due

to

the practice of staining themselves with red ochre. This

.was obtained from naturally occurring ferric hydroxide .

(Howley, 1915), for which the ironstones on Bell Island could have provided a ready source. Tnere is no conclusive evidence of native visits to Bell Island, however Mr. Arthur Parsons of Parsonville, Bel l Island, has shown the author a fragment

of a ground, red slate spearhead which had been plowed up.

This implement was subsequently shown to Dr. J. Tuck of the Anthropology Department, Memorial University, who maintains that i t is of prehistoric origin, probably of a type used t o hunt seal<>.

I t appears that earl y white settlers knew of the ironstones probably as far back as the 18th century. Rev.

L. A. Anspach, author of "A History of the Island of New- foundland" (1819), citest

" ... traditionary reports which are repeated with confidence by the oldest inhab- itants (of Newfoundland) ... that there is an iron mine at Back Cove, on the northern side of Bell Isle near Portugal Cove," (pp. )67-368).

These reports we~ither not generally known or were

forgotten, because the commer~ ial "discovery" of the deposits came only in the 1890's.

The first mention of the Bell Island st~ata in the

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\ 9

geological literature was that of Jukes (1842 ), who made a general sc.:.rve·y of Newfoundland geology as part of his

"Ex:::ursions ir. and around Newfoundland during the Years 1839 3.nd 1840". fie refers to the ":Oelle Isle shale and gri tstone"

?.JJd gives a brief but accurate lithological description. · Jukes did not rec~gnize the · ironstones, but he did note "a reddish stone" and "red marl" (p. 250) and, elsewhere in his report, the presence of a "bright red sandstone, 8 feet thick, in the upper beds of Belle Isle" (p. 276). Of what is now k.""!own to be a rich ichnofaunal assemblage, Jukes wrote 1

'"On the firm pieces (of 'slate •) occur singular markings in relief which sometimes assume the shape of leaves, branches or other organic bodies, but which are, I believe, entirely concretionary" (p. 250).

AlexG.nder Murray (1881) published a stratigraphic cross-section through the Avalon Peninsula includin& a short lithological description of Kellys Island, Little Bell and Bell Island. The uppermost strata that he described were th~

white quartzites in the middle of the Bell Island sequence, thus missing the thick ironstone deposits in the upper beds.

The eventual discdvery of the iron ores is recounted by Rev. Moses Harvey (1902)•

"A fisherman picked up what he supposed to be a heavy stone as ballast for his boat.

Upon arrival in St. John's it was discovered by a mining prospector who investigated it and became satisfied of its value".

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•

10

The rights to the property were acquired by the Nova Scotia Steel and Coal Co. in 1894 and quarrying began in 1895.

During 1912, 1913 and 1914 Van Ingen of Princeton University led field parties to examine the Cambro-

Ordovic~an rocks of Conception and Trinity Bays, resulting in a series of contributions to the geology of Newfoundland by the Princeton University Department of Geology. Van

I:~gen (1914) p:r;oduced a "table of geological formations of the Cambrian and Ordovician Systems about Conception and Trinity Bays" from his field work. He divided the Lower Ordovician of Conception Bay into· the Bell Island Series and the Wabana Series, and named twelve formations based on paleontology and the appearance of the ore beds in the sequence. One of his students, A. 0. Hayes, undertook a field study of the· ore deposits during the summer of 1912, subsequently writing his doctoral thesis on the Wabana • iron

ores, The thesis was published as a memoir of the Geological Survey df Canada (Hayes, 1915).

Hayes concluded that the oolitic iron ores were of primary origin deposited under shallow water conditions and he discussed the chemistry of precipitation making the following poiritss

-"p~netration of the oolites by boring algae indicate the probable close association of algae with ore deposition.

-"the alternating concentric layers of hematite and chamosite in the spherules suggest that most of the hematite was formed contemp-

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11

<;>raneously with the . chamosLte. (p. 70).

-"it seems probable ^tha~the iron· wa$

derived by long continued weathering of earlier crystalline and sedimentary rocks, the solution·

of their iron content by mineral and vegetable acids an~ subsequent transportation of .the iron salts into the sea. (p. 71 ).

-"Cayeux' s theory ... that an original limestone has been transformed into ·an oolitic iron ore is absolutely untenable for the Wabana ore . " ( p . 7 2 ) •

In 1926, B. F. Howell summarized the Cambro-Ordovician ) stratigraphic column of southeastern Newfoundland, compiling much of his information from the Princeton expedi~ions.

Hayes (1929) published an article on "Further Studies of the origin of the Wabana Iron Ores of Newfoundland". His observations indicated that the Wabana iron ore, during the process of formation, was exposed

,

to oxidizing conditions in a very shallow marine basin that was exposed to air over wide areas at low tide.

E.· R. Rose 0952) produced a map and ge olog.ical report of the Torbay map area, Newfoundland. Included in this report is the Lower qrdovician sequence of Conception Bay. In his report Rose changed Van Ingen•s Bell Island Series and Wabana Series to group status, but otherwise the

scope of Ro~e·s work did not allow a more detail~d description of the strata. His observations on the depositional environment were the following•

"Exclusive of the hematite beds, the r6cks

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