Northeastern Section of the Geological Society of America

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Edited by

David C. Roy Department of Geology and Geophysics Boston College Chestnut Hill, Massachusetts 02167

1987

Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3731364/9780813754116_frontmatter.pdf by guest on 25 September 2021 Acknowledgment

Publication of this volume, one of the Centennial Field Guide Volumes of The Decade of North American Geology Project series, has been made possible by members and friends of the Geological Society of America, corporations, and government agencies through contributions to the Decade of North American Geology fund of the Geological Society of America Foundation. Following is a list of individuals, corporations, and government agencies giving and/or pledging more than $50,000 in support of the DNAG Project: ARCO-Exploration Company -- Phillips Petroleum Company Chevron Corporation Shell Oil Company Cities Service Company Caswell Silver Conoco, Inc. Sohio Petroleum Corporation Diamond Shamrock Exploration Standard Oil Company of Indiana Corporation Sun Exploration and Production Company Exxon Production Research Company Superior Oil Company Getty Oil Company Tenneco Oil Company Gulf Oil Exploration and Production Texaco, Inc. Company Union Oil Company of California Paul V. Hoovler Union Pacific Corporation and Kennecott Minerals Company its operating companies: Kerr McGee Corporation Champlin Petroleum Company Marathon Oil Company Missouri Pacific Railroad Companies Rocky Mountain Energy Company McMoRan Oil and Gas Company Union Pacific Railroad Companies Mobil Oil Corporation Upland Industries Corporation Pennzoil Exploration and Production U.S. Department of Energy Company

Centennial field guide All materials subject to this copyright and included in this volume may be photocopied for the noncommercial “Prepared under the auspices of the regional Sections purpose of scientific or educational advancement. of the Geological Society of America as a part of the Decade of North American Geology (DNAG) Project”— Copyright is not claimed on any material prepared Vol. 6, pref. by government employees within the scope of their vol. : maps on lining papers. employment. Includes bibliographies and indexes. Contents —v. 5. Northeastern Section of the Published by the Geological Society of America, Inc. Geological Society of America/ edited by David C. Roy. 3300 Penrose Place, P.O. Box 9140, Boulder, Colorado 80301 —v. 6. Southeastern Section of the Geological Society of America / edited by Thornton L. Neathery. Printed in U.S.A. 1. Geology—United States-Guide-books. 2. Geology— Canada-Guide-books. 3. United States-Description and travel—1981- —Guide-books. 4. Canada—Description and travel—1981 – —Guide-books. I. Title Geological Society of America. QE77.C46 86-11986 ISBN 0-8137-5405-4 (V. 5)

Front Cover: Fall color highlights the banks of South Branch Ponds Brook where it flows over exposures of the Black Cat Member of the Traveler Rhyolite in Baxter State Park, Maine (Site 64). Here gently dipping surfaces on the right bank of the stream are roughly parallel to a compaction foliation (eutaxitic texture) in the ash-flow tuff. Crude columnar joints are perpendicular to the foliation. (Photo by D. C. Roy) . . . viii

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Preface ...... xix

Foreword ...... xx

1. Active and abandoned incised meanders of the Potomac River, south of Little Orleans, Maryland ...... 1 Michael F. Fitzpatrick

2. The Silurian section at Roundtop Hill near Hancock Maryland ...... 5 John D. Glaser

3. Maryland's Cliffs of Calvert: A fossiliferous record of mid-Miocene inner shelf and coastal environments ...... 9 Peter R. Vogt and Ralph Eshelman

4. Baltimore gneiss and the Glenarm Supergroup, northeast of Baltimore, Maryland . . . . . 15 Jonathan Edwards, Jr.

5. Cape Henlopen spit: A late Holocene sand accretion complex at the mouth of Delaware Bay, Delaware ...... 19 John C. Kraft and Anne V. Hiller

6. Upper Cretaceus and Quaternary stratigraphy of the Chesapeake and Delaware Canal ...... 23 Thomas E. Pickett

7. Banded gneiss and Bringhurst gabbro of the Wilmington Complex in Bringhurst Woods Park, northern Delaware ...... 25 Mary Emma Wagner, Lee Ann Srogi, and Elayne Brick

8, 9. Upper Paleozoic stratigraphy along the Allegheny topographic front at the Horseshoe Curve, west-central Pennsylvania ...... 29 Jon D. Inners

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10. The Birmingham window; Alleghanian décollement tectonics in the Cambrian-Ordovician succession of the Appalachian Valley and Ridge Province, Birmingham, Pennsylvania ...... 37 Rodger T. Fain

11. Mississippian-Pennsylvanian boundary and variability of coal-bearing facies at Curwensville Reservoir, Clearfield County, Pennsylvania ...... 43 Thomas M. Berg

12. The Susquehanna River Water Gaps near Harrisburg, Pennsylvania ...... 47 Donald M. Hoskins

13. Rheems quarry; The underside of a Taconian nappe in Lancaster County, Pennsylvania ...... 51 Rodger T. Fain and Alan R. Geyer

14. Sequence of structural stages of the Alleghany orogeny at the Bear Valley Strip Mine, Shamokin, Pennsylvania ...... 55 Richard P. Nickelsen

15. Upper Mississippian to Middle Pennsylvanian stratigraphic section, Potts vine, Pennsylvania ...... 59 Jeffrey Ross Levine and Rudy Slingerland

16. Structural and sedimentologic characteristics of the Greenwich slice of the Hamburg klippe: An ancient subduction complex in eastern Pennsylvania ...... 65 Gary G. Lash

17. Ordovician through Mississippian rocks, Lehigh River, Carbon County, Pennsylvania ...... 71 W. D. Seven

18. The Hickory Run boulder field, a periglacial relict, Carbon County, Pennsylvania ...... 75 W. D. Seven

19. The Wissahickon Schist type section, Wissahickon Creek, Philadelphia, Pennsylvania ...... 77 Maria Luisa Crawford

20. Late Triassic cyclic sedimentation: Upper Lockatong and lower Passaic Formations (Newark Supergroup), Delaware Valley, west-central New Jersey ...... 81 Franklyn B. Van Houten

21. Cretaceous stratigraphy of the Atlantic Coastal Plain, Atlantic Highlands of New Jersey...... 87 Richard K. Olsson

22. The Palisades Sill and Watchung basalt flows, northern New Jersey ...... 91 John H. Puffer

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23, 24. Niagara Falls and Gorge, New York-Ontario ...... 97 Carlton E. Brett and Parker E. Calkin

25. The Gowanda Hospital late Pleistocene site, western New York ...... 107 Parker E. Calkin

26. Alleghanian deformation within shales and siltstones of the Upper Devonian Appalachian Basin, Finger Lakes District, New York ...... 113 Terry Engelder, Peter Geiser, and Dov Bahat

27. Lower Devonian limestones, Helderberg Escarpment, New York ...... 119 Donald W. Fisher

28. Exposures of the Hudson Valley Fold-Thrust Belt, west of Catskill, New York ...... 123 Stephen Marshak and Terry Engelder

29. Strand-line facies of the Catskill Tectonic Delta Complex (Middle and Upper Devonian) in eastern New York State ...... 129 Kenneth G. Johnson

30. Igneous and contact metamorphic rocks of the Cortlandt Complex, Westchester County, New York ...... 133 Robert J. Tracy, Nicholas M. Ratcliffe, and John F. Bender

31. Geology of Manhattan Island and the Bronx, New York City, New York ...... 137 Charles Merguerian and Charles A. Baskerville

32. The Taconic Allochthon Frontal Thrust: Bald Mountain and Schaghticoke Gorge, eastern New York ...... 141 William Bosworth and Steven Chisick

33. The mid-Ordovician section at Crown Point, New York ...... 147 Brewster Baldwin

34. Geology of the Adirondack-Champlain Valley boundary at the Craig Harbor faultline scarp, Port Henry, New York ...... 151 J. Gregory McHone

35. Leucogranitic gneiss bodies and associated metasedimentary rocks, Adirondack lowlands, near Canton, New York ...... 155 William D. Romey, William T. Elberty, Jr., and Russell S. Jacoby

36. The geology of Cameron’s Line, West Torrington, Connecticut ...... 159 Charles Merguerian

37. Mesozoic sedimentary and volcanic rocks in the Farmington River Gorge, Tariffville, Connecticut ...... 165 Norman H. Gray

38. The Willimantic fault and other ductile faults, eastern Connecticut ...... 169 R. P. Wintsch

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39. Ledyard recessional moraine, Glacial Park, Connecticut ...... 175 Richard Goldsmith

40. Geologic relationships of Permian Narragansett Pier and Westerly Granites and Jurassic lamprophyric dike rocks, Westerly, Rhode Island ...... 181 O. Don Hermes

41. The Alleghanian Orogeny in the Narragansett Basin area, southern Rhode Island ...... 187 Daniel P. Murray

42. Alleghanian deformation in the southern Narragansett Basin, Rhode Island ...... 191 S. Mosher, R. J. Burks, and B. H. Reck

43. Cambrian stratigraphy and structural geology of southern Narragansett Bay, Rhode Island ...... 195 James W. Skehan, Michael J. Webster, and Daniel F. Logue

44. The Rowe Schist and associated ultramafic rocks along the Taconian suture in western Massachusetts ...... 201 Norman L. Hatch, Jr., and Rolfe S. Stanley

45. The Bloody Bluff fault zone near Lexington, Massachusetts ...... 205 A. E. Nelson

46. Stratigraphy of the Boston Bay Group, Boston area, Massachusetts ...... 209 Richard H. Bailey

47,48. Glacial and coastal geology, Cape Cod National Seashore, Massachusetts ...... 213 John J. Fisher and Stephen P. Weatherman

49. Wisconsinan and pre-Wisconsinan drift and Sangamonian marine deposits, Sankaty Head, Nantucket, Massachusetts ...... 221 Robert N. Oldale

50. The Champlain thrust fault, Lone Rock Point, Burlington, Vermont ...... 225 Rolfe S. Stanley

51. Stratigraphy of the Cambrian platform in northwestern Vermont ...... 229 Charlotte J. Mehrtens

52. Taconic sedimentary rocks near Fair Haven, Vermont ...... 233 Brewster Baldwin and Andrew V. Raiford

53. Barre granite quarries, Barre, Vermont ...... 239 Dorothy A. Richter

54. Mascoma Dome, New Hampshire: An Oliverian gneiss dome ...... 243 Richard S. Naylor

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55, 56. Metamorphic stratigraphy of the classic Littleton area, New Hampshire ...... 247 Robert H. Moench, Katrin Hafner-Douglass, Christian. Jahrling II, and Anne R. Pyke

57. Mount Washington-Crawford Notch area, New Hampshire ...... 257 Richard P. Goldthwait, Marland P. Billings, and John W. Creasy

58. Geology of the Belknap Mountains Complex, White Mountain Series, central New Hampshire ...... 263 Wallace A. Bothner and Marc C. Loiselle

59. The Massabesic Gneiss Complex and Permian granite near Milford, south-central New Hampshire ...... 269 John N. Aleinikoff and Julian W. Green

60. Stratigraphy of the Rangeley area, western Maine ...... 273 Robert H. Moench and Eugene L. Boudette

61. Structure and stratigraphy of the Central Maine Turbidity Belt in the Skowhegan-Waterville region ...... 279 Allan Ludman and Philip H. Osberg

62. Casco Bay group, South Portland and Cape Elizabeth, Maine ...... 285 Arthur M. Hussey II

63. Silurian-Lower Devonian volcanism and the Acadian orogeny, the Eastport area, Maine ...... 289 Olcott Gates

64, 65. Traveler Rhyolite and overlying Trout Valley Formation and the Katahdin Pluton; A record of basin sedimentation and Acadian magmatism, north-central Maine ...... 293 Douglas W. Rankin and Rudolph Hon

66. Geomorphology and glacial geology of the Mount Katahdin region, north-central Maine ...... 303 D. W. Caldwell and Lindley S. Hanson

67. Type section of the Early Ordovician Shin Brook Formation and evidence of the Penobscot orogeny, northern Penobscot County, Maine ...... 307 Robert B. Neuman

68. The Mapleton Formation: A post-Acadian basin sequence, Presque Isle, Maine ...... 311 David C. Roy and Kenneth J. White

69. Komatiites in Munro Township, Ontario ...... 317 N. T. Arndt and A. J. Naldrett

70. The Sudbury Structure, Sudbury, Ontario ...... 323 P. E. Giblin

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71. Transect along the Central Metasedimentary Belt/Central Gneiss Belt Boundary Zone, Grenville Province, Ontario Highway 35, Minden Area, 0ntario ...... 327 R. M. Easton

72. Supracrustal rocks of the Central Metasedimentary Belt of the Grenville Province, Madoc-Marmora-Havelock area, Ontario ...... 333 R. M. Easton, T. R. Carter, and J. R. Bartlett

73. Paleozoic-Precambrian unconformity near Burleigh Falls, 0ntario Highway 36, 0ntario ...... 337 R. M. Easton

74. Quaternary geology of Toronto area, Ontario ...... 339 David R. Sharpe

75. The Port Talbot interstadial site, southwestern Ontario ...... 345 Aleksis Dreimanis

76. Structure and Ordovician stratigraphy of the Ottawa area, southern Ontario ...... 349 D. A. Williams and P. G. Telford

77. Glacial stratigraphy of the central St. Lawrence Lowland near Lac St. Pierre, Quebec ...... 353 Nelson R. Gadd

78. The late mid-Ordovician transgressive sequence and the Montmorency Fault at the Montmorency Falls, Quebec ...... 357 John Riva and R. K. Pickerill

79. The Oak Hill Group, Richmond, Québec: Termination of the Green Mountains-Sutton Mountains Anticlinorium ...... 363 Robert Marquis, Jacques Bé1and, and Walter E. Trzcienski, Jr.

80. Thetford Mines ophiolite, Quebec ...... 369 Roger Laurent and Brewster Baldwin

81. The Ordovician-Silurian boundary succession at Cap Henri, Anticosti Island, Québec ...... 373 Allen Alexander Petryk

82. Silurian stratigraphy and facies, Port-Daniel/Gascons and Black-Cape areas, southern Gaspé Peninsula, Québec ...... 379 Pierre-André Bourque

83. Late Ordovician sedimentary rocks and trace fossils of the Aroostook-Matapedia Carbonate Belt at Runnymede, Restigouche River, northern New Brunswick ...... 385 R. K. Pickerill

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84. Stratigraphy and tectonics of Miramichi and Elmtree terranes in the Bathurst area, northeastern New Brunswick ...... 389 L. R. Fyffe

85. Oil shales of the Albert Formation at Frederick Brook in southeastern New Brunswick ...... 395 C. St. Peter

86. Cambrian stratigraphy in the Hanford Brook area, southern New Brunswick, Canada ...... 399 S. R. McCutcheon

87. The Avalonian terrane around Saint John, New Brunswick, and its deformed Carboniferous cover ...... 403 K. L. Currie

88. A classic Carboniferous section; Joggins, Nova Scotia ...... 409 Martin R. Gibling

89. Jurassic basalts of northern Bay of Fundy region, Nova Scotia ...... 415 George R. Stevens

90. The Late Precambrian Antigonish Terrane (a periarc basin) unconformably overlain by Paleozoic overstep rocks typical of the Avalon Composite Terrane, near Antigonish, Nova Scotia ...... 421 J. B. Murphy and J. D. Keppie

91. Glacial advances and sea-level changes, southwestern Nova Scotia, Canada ...... 427 D. R. Grant

92,93. Sedimentology, structure, and metallogeny of the Goldenville Formation, Meguma Terrane, Isaacs Harbour, Nova Scotia ...... 433 J. D. Keppie

94. The Annieopsquotch Complex, southwest Newfoundland; An Early Ordovician ophiolite and its unconformable Silurian cover ...... 441 G. R. Dunning

95. Late Quaternary glaciation and sea-level change, southwest Newfoundland, Canada ...... 445 I. A. Brookes

96. The Bay of Islands ophiolite; A cross section through Paleozoic crust and mantle in western Newfoundland ...... 451 J. Malpas

97. Ophiolitic mélange along the Baie Verte Line, Coachman’s Harbour, Newfoundland ...... 457 James Hibbard

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98. Silurian stratigraphy and mélanges, New World Island, north central Newfoundland ...... 463 Douglas Reusch

99. Stratigraphy of Cambrian rocks at Bacon Cove, Duffs, and Manuels River, Conception Bay, Avalon Peninsula, eastern Newfoundland ...... 467 M. M. Anderson

100. Late Precambrian glaciomarine sequence, Conception Group, Double Road Point, St. Mary’s Bay, southeast Newfoundland ...... 473 M. M. Anderson

Index ...... 477

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TOPICAL AND GEOGRAPHIC CROSS-REFERENCES (CONTINUED)

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This volume is one of a six-volume set of Centennial Field Guides prepared under the auspices of the regional Sections of the Geological Society of America as a part of the Decade of North American Geology (DNAG) Project. The intent of this volume is to highlight the best and most accessible geologic localities of the northeastern United States and eastern Canada for the geologic traveler and for students and professional geologists interested in major geologic features of regional significance. The leadership provided by the editor, David C. Roy, and the support provided to him by the Northeastern Section of the Geological Society of America and by the Department of Geology and Geophysics of Boston College are greatly appreciated. Drafting services were offered by the DNAG Project to those authors of field guide texts who did not have access to drafting facilities. Particular thanks are given here to Ms. Karen Canfield of Louisville, Colorado, who prepared final drafted copy of many figures from copy provided by the authors. In addition to Centennial Field Guides, the DNAG Project includes a 29-volume set of syntheses that constitute The Geology of North America, and 8 wall maps at a scale of 1:5,000,000 that summarize the geology, tectonics, magnetic and gravity anomaly patterns, regional stress fields, thermal aspects, seismicity, and neotectonics of North America and its surroundings. Together, the synthesis volumes and maps are the first coordinated effort to integrate all available knowledge about the geology and geophysics of a crustal plate on a regional scale. They are supplemented, as a part of the DNAG project, by 23 Continent– Ocean Transects providing strip maps and both geologic and tectonic cross-sections strategi- cally sited around the margins of the continent, and by several related topical volumes. The products of the DNAG Project have been prepared as a part of the celebration of the Centennial of the Geological Society of America. They present the state of knowledge of the geology and geophysics of North America in the 1980s, and they point the way toward work to be done in the decades ahead.

Allison R. Palmer Centennial Science Program Coordinator

xix

The region of the Northeastern Section of the Geological Society of America includes the northeastern states of the United States and the eastern provinces of Canada, including most of Ontario. In many ways the science of geology in North America was born and nurtured in this region with the pioneer work of such people as James Hall, in the United States, and Sir William Logan, in Canada, just a decade or so after publication of Charles Lyell’s Principles of Geology Lyell himself visited the region in the early 1840s and visited some of the sites described in this volume. With approximately 200 colleges and universities offering programs in the geological sciences and the very active work of the United States Geological Survey, the Geological Survey of Canada, and the several state and provincial surveys, it is understandable why the region of the Northeastern Section is one of the most studied and restudied terranes on the continent. Despite this long history of intense study the region is still the source of new information, new ideas, and new problems. This field guide project began with selection of the editor by the Management Board of the Section in the spring of 1982. The commission given the editor was to produce a field guide to the Northeastern Section, containing a hundred “classic” field sites, to be a part of a Decade of North American Geology (DNAG) field guide series. This sort of field guide had never been attempted by the Society before but it seemed like a good idea since no other DNAG volumes were planned that would document the field evidence on which the regional syntheses are necessarily based. Although there is a rich library of guidebooks by local and regional societies, associations, and conferences, most of those guidebooks are not generally available. The Management Board suggested that everyone who has, or is, working in the region be given an opportunity to nominate sites and that selection be made by a panel of geologists familiar with the region. This was accomplished by mailing nomination materials to all members of the Section, as well as by promotions at Section meetings and notices by the Society to all members. Individuals familiar with the geology of each state/province reviewed the nominations and made recommendations both as to which nominated sites should be included and which other sites should be sought. The Management Board also considered it important that the guide be regionally and topically “balanced” insofar as possible with the limited number of sites. Although the “sites” were originally thought of as single outcrops, it early became clear that individual exposures rarely provide sufficient evidence to establish major conclusions about the geologic history of a region. It is the integration of observations from several, sometimes many, outcrops that usually convince us of the extent and importance of geologic events. In much of this wooded region, one cannot usually describe a stratigraphic section, delineate a major structure, or explore a moraine without using information from numerous

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exposures. Therefore most of the sites described in this volume are small areas containing diverse geologic information of regional importance. Individual exposures are designated as numbered “stops” (sometimes with “stations” within them), but the descriptions are written so that users can examine the stops in any order. Although collecting of fossils, minerals, and rocks is possible and encouraged at many of the sites described here, sites that are important primarily as collecting localities were not included because of the limited audience to which they would appeal and also to prevent excess “people pressure” on them. Localities featuring archetypical examples of geologic features without also providing information of widespread significance to our understanding of the geologic history of the region were also not given priority. In some cases, authors have requested that visitors to the site, or to some stops, not collect or mar the outcrop with hammers or other tools. Please respect these cautions so that future visitors can see all of the things that make the site important, The limitation on the number of sites makes it, of course, impossible to include all important sites in such a large region, This field guide, and the others in the series, can however provide a foundation upon which to build field trips or study particular aspects of the geology for geologists unfamiliar with the geology of the region. Many of the sites have been described, at least in part, in guidebooks produced by regional organizations. These previous guidebook descriptions have been cited in the site articles to aid further investigation. The value of this field guide lies, to no small extent, in its availability to a wide audience and its presence in libraries across the continent, A special attempt was made to ensure that most major urban areas in the region have sites in or near them so that visitors with short stays can explore at least some aspect of the local geology. Topically, 15 of the sites deal with Quaternary Geology (glacial geology, geomorphology, and coastal geology) with the remainder treating bedrock. Most of the bedrock sites illustrate some aspect of the Precambrian-through-Mesozoic history of the region; three bedrock sites are significant in large part for their economic geology. As shown in the index maps at the front of this volume, the areal distribution of sites is good. They are arranged by state and province, from south to north, with ordering within each state or province from west to east. This arrangement should assist users coming from the rest of the continent to locate sites as they travel by automobile into the Northeastern Section. One effect of this arrangement is the separation of the United States portion of the guide from that for eastern Canada, which should not be interpreted as suggesting that the geology of the two countries is somehow divided. The New England states are also together in the middle of the book. Those interested in tracing some geologic feature (such as the ophiolitic suture within the Appalachi- an Mountains) or examining sites dealing with a particular general topic (e.g. igneous rocks, glacial geology, etc.) will find the Topical Cross-references for Field Guide Sites in the Contents useful. Unfortunately, some bedrock domains, such as the allochthonous Pre- cambrian massifs along the western margin of the Appalachian orogen in the Hudson Highlands, the Berkshire and Green Mountains in New England, and the Long Range of Newfoundland, are not represented or are under-represented in the guide. In most cases the absence of sites within certain terranes is usually the result of a lack of volunteers despite considerable effort; in a few cases, it results from the failure of an author to produce an article on a site that was accepted for the book. In addition to obvious contributions by the 120 authors and coauthors, many people have helped to make this field guide come together before the end of the Decade of North American Geology. The following were particularly helpful in selection of the sites from the almost 200 nominations: Gail M. Ashley, Michael Bell, Harold W. Borns, Leslie R. Fyffe, Richard Goldsmith, Douglas R. Grant, David Harper, O. Donald Hermes, Donald M. Hoskins, Yngvar Isachsen, Robert R. Jordan, Paul F. Karrow, J. Duncan Keppie, John B. Lyons, Allan Ludman, Rolfe S, Stanley, Walter E. Trzcienski, Kenneth N, Weaver, and Harold Williams. The work of Robert D. Collins was essential in the processing of manu- scripts that soon began overwhelming the editor. The Department of Geology and Geophysics of Boston College provided important support without which the work of the editor would

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have been impossible. The Management Board of the Section provided funds to support the Field Guide Project. A special acknowledgment is here made to the many individuals who nominated sites that were not selected. The support of the Section’s DNAG effort indicated by the efforts put into these nominations is greatly appreciated. A final word of caution. Most of the sites contain stops that are on private property. Publication of a description of the stop in this field guide in no way constitutes approval by owners for access by visitors. Users must obtain permission on their own for each visit. In addition, the stops of each site present certain levels of risk that are borne by the visitor and not by land owners, authors, or the Society. Visit the sites with care and enjoy!

David C. Roy Chestnut Hill, Massachusetts December 29, 1986

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