Atlantic Continental Shelf and Slope 

of the United States 

Heavy Minerals of the Continental Margin From 

Southern Nova Scotia to Northern New Jersey 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 529-G 

Atlantic Continental Shelf and 

Slope of the United StatesHeavy Minerals of the 

Continental Margin from 

Southern Nova Scotia to 

Northern New Jersey 

By DAVID A. ROSS 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 529-G 

A study of the source and recent geologic history 

of the heavy minerals on the Atlantic continental 

margzn 

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON: 1970 
UNITED STATES DEPARTMENT OF THE INTERIOR 

WALTER J. HICKEL, Secretary 

GEOLOGICAL SURVEY 

William T. Pecora, Director 

For sale by the Superintendent of Documents, U.S. Government Printing Office 

Washington, D.C. 20420 - Price 50 cents (paper cover) 
Abstract------------------------------------------- Introduction ______________________________________ _ 

General description of the area __________________ _ Previous work _________________________________ _ 

Field work _____________________________________ _ 

Methods of study ______________________________ _ 

Acknowledgments _____________ ----- __ ------ ____ _ 

Mineral components and their areal distribution _______ _ Heavy minerals ________________________________ _ 

Nonopaque heavy minerals ____ -------------- Opaque heavy minerals _____________________ _ 

Altered heavy minerals _____________________ _ 

Effects of grain size ____________________________ _ 

Light minerals _____________________________ ----_ 

Terrigenous materiaL __________ ----- _______ _ Glauconite ________________________________ _ 

Biogenous materiaL ______________ --- __ -- ___ _ 

CONTENTS 

Page 

G1 

1 

1 

2 

2 

2 

2 

4 

4 

4 

4 

4 

5 

16 

16 

16 

16 

Source areas and supply of sediments------------------

General geology of the shelf and adjacent land area __ Effects of glaciation ____________________________ _ 

Supply of sediments ____________________________ _ 

Heavy.,.mineral associations _________________________ _ 

Variability in mineral composition _______________ _ 

Source and dispersal of sediments _________ --- ________ _ 

Gulf of Maine-Georges Bank area _________ -_- ___ _ 

The Long Island margin area ____________________ _ 

Classification of sediments _________ --------------- __ _ 

Recent sediments ________ -----------------------

Relict sediments ______ -- ___ ---------------------

Dispersal and modification of sediments ______ ---------

Conclusions __________________ - - _____ - __ - -----------

References cited _______________________ ----- ______ -_ 

ILLUSTRATIONS 

Page 

G20 

20 

20 

23 

23 

23 

24 

24 

33 

34 

34 

34 

36 

38 

38 

Page 

FIGURE 1. Map showing general bathymetry of area between southern Nova Scotia and northern New Jersey_________ G3 

2-6. Mineral distribution maps: 

2. Garnet and amphiboles-------------------------------------------------------------------- 7 

3. Augite and epidote ______________________________ ---_--- ________ --------------------------- 9 

4. Tourmaline and staurolite _____________________________________________ -_---- ____ ----------- 11 

5. Hypersthene and andalusite ______________________________________________________________ -- 13 

6. Opaque heavy minerals and altered heavy minerals-------------------------------------------- 15 

7-10. Maps showing: 

7. Distribution of median grain sizes of material finer than 2 mm ________________________________ -- 17 

8. Distribution of quartz and feldspar and iron-stained quartz and feldspar-_--------------------.. --· 19 

9. Generalized geology of the land area--------------------------------------------------------· 21 

10. Glacial moraines, outwash sediments, and postglacial marine sediments on land_------------------ 22 

11. Diagram showing heavy-mineral composition of sediments from major rivers ___________________________ . 24 

12. Map showing heavy-mineral provinces _______________________________________________________ --- 25 

13. Diagrams showing heavy-mineral composition of sediments collected from the Gulf of Maine region_------- 27 

14. Graphs showing percentages of common nonopaque heavy minerals in some of the heavy-mineral provinces___ 28 

15. Map showing garnet-staurolite ratio contours _______________________________________ ----- _________ --- 31 

16. Graph showing relation of percentages of common heavy minerals to media~ grain size of the sand fraction 

in the Georges Bank garnet province------------------------------------------------------------ 32 

17. Map showing classification of bottom sediments on the continental margin______________________________ 35 

18. Map showing dispersal pattern of sediments _______________________________________ ------------------ 37 

m 
IV 

TABLE 

CONTENTS 

TABLES 

1. Nonopaque heavy minerals in sediments of the continental margin between southern Nova Scotia and northern 

NewJerseY---------------------------------------------------------------------------------

2. Mineral frequency of the common nonopaque heavy minerals in the sediments of the continental margin 

between southern Nova Scotia and northern New JerseY------------------------------------------

3. Description of the common nonopaque heavy minerals in the sediments of the continental margin between 

southern Nova Scotia and northern New Jersey _________ --_------------------------------------- 4. Relations between heavy-mineral percentage and median size of the sand fraction _______________________ _ 

5. Discharge and drainage area for the major rivers of the northern part of the east coast of the United States __ _ 

6. Heavy-mineral associations of the Gulf of Maine-Georges Bank area and of the Long Island margin area ____ --

7. Relation between heavy-mineral percentage and median grain size of the sand fraction of heavy-mineral associations in the Gulf of Maine-Georges Bank area and in the Long Island margin area ________________ - -

8. Relation of garnet and staurolite to the median diameter of the sand fraction of all samples ______________ _ 

9. Common heavy minerals in the Georges Bank garnet and "complex" provinces--------------------------

10. Common heavy minerals in the Georges Bank garnet and mixed amphibole-garnet provinces _____________ _ 

11. Classification of the sediments on the continental margin between southern Nova Scotia and northern New 

JerseY--------------------------------------------------------------------------------------

Page 

G4 

4 

5 

16 

23 

26 

27 

30 

32 

33 

34 
ATLANTIC CONTINENTAL SHELF AND SLOPE OF THE UNITED 

STATES-HEAVY MINERALS OF THE CONTINENTAL MARGIN 

FROM SOUTHERN NOVA SCOTIA TO NORTHERN NEW JERSEY1 

By DAVID A. Ross, Woods Hole Oceanographic Institution 

ABSTRACT 

A study of heavy minerals and light minerals from the sand 

fraction of 229 surface sediment samples collected on the continental margin between southern Nova Scotia and northern 

New Jersey shows 15 different heavy-mineral provinces. The 

percentages of several heavy-mineral species over the entire 

area are dependent on grain size: garnet, staurolite, andalusite, 

titanite, and opaque grains are more prevalent in the coarser 

sized sediments, whereas amphiboles, epidote, augite, and altered grains are more common in the finer sized sediments. 

However, the size effects generally do not account for the differences between the heavy-mineral provinces. These differences are more closely related to source and other geologic 

factors. 

The sediments can be classified into two major groups: recent sediments and relict sediments. Recent sedimentation 

is represented by three heavy-mineral provinces whose sediments were supplied by rivers that flow into the Gulf of Maine: 

the Penobscot amphibole, Kennebec amphibole, and Merrimack 

garnet. Two other provinces, located off Narragansett Bay 

and in Long Island Sound, may also be, in part, of recent origin. 

The remaining provinces are composed mainly of relict sediments. Five of these provinces are glacial in origin; they include, 

in the Gulf of Maine, an augite and an amphibole province, 

both of which have low-stability mineral assemblages typical 

of their source regions in New England. The material in the 

Gulf of Maine has had minimal reworking, probably due in 

part to the sheltering effect of Georges Bank. The other glacial 

provinces, the Cape Cod garnet, Long Island garnet, and Long 

Island garnet-staurolite, have stable mineral assemblages that 

reflect their high degree of reworking by waves and currents. 

Some glacial material is found on the continental slope and rise 

off Northeast Channel and Georges Bank. 

Georges Bank is underlain by the offshore extension of the 

Coastal Plain formations. These formations have been reworked 

by waves and currents to give rise to a coarse-grained "lag 

deposit" having a stable heavy-mineral assemblage. Some 

Coastal Plain material removed by glaciers from the Gulf of 

Maine may also have been deposited on Georges Bank. Finegrained sediments have been winnowed from Georges Bank and 

transported both landward into the Gulf of Maine and seaward 

off the bank. These fine-grained sediments have been mixed 

with glacial material from the Gulf of Maine on the landward 

side and with glacial material from the Long Island shelf and 

deep-sea pelagic '3ediments on the seaward side. 

1 Contribution 1983 of the Woods Hole Oceanographic Institution, based on work 

done under a program conducted jointly by the U.S. Geological Survey and the 

Woods Hole Oceanographic Institution and financed by the U.S. Geological Survey. 

Mineral composition is primarily a function of source, although 

it has been modified by selective sorting, weathering, and 

diagenetic processes. Modification is most pronounced in the 

high-energy areas of Georges Bank, on Nantucket Shoals, and 

on the Long Island shelf. Clean quartzose sand is found where 

the modification of the heavy minerals is most pronounced; 

stained grains are more typical in the Gulf of Maine, where 

reworking is minor. The sediments of the high-energy areas 

are considered mature on the basis of their stable mineral composition and good sorting. Sediments in the Gulf of Maine are 

judged immature on the basis of their low-stability heavymineral suites and poor sorting. The sediments of much of the 

continental slope and rise are fine grained and have abundant 

biogenous material and a heavy-mineral suite of intermediate 

stability. 

Dispersal of sediments is mainly offshore. Some sediment, 

however, is probably moving along the continental shelf and 

slope off Long Island, and some sediment moves off Georges 

Bank into the Gulf of Maine. 

INTRODUCTION 

Sand-sized (2-0.062 mm) light and heavy minerals 

have traditionally been used to determine the source 

and depositional history of sediments. The heavy minerals have been emphasized because their greater 

mineralogic variety facilitates making fine distinctions 

between source areas. 

The purpose of this report is: ( 1) to describe the 

heavy-mineral composition of the sand-sized fraction 

of the sediments on the continental margin between 

Nova Scotia and New Jersey, (2) to delineate heavymineral provinces and determine their source and dispersal patterns, and (3) to determine the effects of 

environment on mineral composition. Light-mineral 

analyses, although not a major part of this study, also 

helped achieve these purposes. 

GENERAL DESCRIPTION OF THE AREA 

The topography of the continental shelf in the study 

area is complex (see U chupi, 1965a). There are numerous small basins on the inner shelf and a series of 

large banks on the outer shelf (fig. 1) off Nova Scotia. 

Between Nova Scotia and the Canadian mainland is the 

Bay of Fundy, which occupies a broad synclinal Triassic 

Gl 
G2 ATLANTIC CONT~ENTAL SHELF AND SLOPE OF THE ~TED STATES 

basin (Tagg and Uchupi, 1966). Seaward of northern 

New England is the Gulf of Maine, a glacially sculptured depression that has at least 21 shallow irregular 

basins separated by low swells or areas of hummocky 

topography (Uchupi, 1965b; Murray, 1947). The Gulf 

of Maine is flanked on the south by Georges Bank, 

which is probably a northeasterly extension of the 

continental shelf of southern New England (Emery.and 

Uchupi, 1965). Northeast and Great South Channels 

border Georges Bank and connect the Gulf of ~Iaine 

with the deeper waters of the continental slope. West 

of Great South Channel is Nantucket Shoals, a shallow 

area of parallel ridges and troughs similar to those on 

Georges Bank (Uchupi, 1965c). Most of the continental 

shelf west of Nantucket Shoals is smooth and has a low 

seaward gradient. 

The continental slope east of Northeast Channel 

has a smooth gentle slope. South of Georges Bank 

the continental slope is steeper and is cut by many 

submarine canyons. The continental slope grades seaward into the gentler sloping continental rise, which 

leads into the deeper abyssal plains. 

PREVIOUS WORK 

Bailey (1851) and Pourtales (1870, '1872) described 

samples from shallow sections of the Altantic coast; 

these samples were collected from the lead weight 

used for making soundings. Shepard and Cohee (1936) 

·concluded that the shelf sediments are mainly relict 

between Delaware Bay and Martha's Vineyard. The 

sediments of the Gulf of Maine were studied by Burbank (1929) and Shepard (1939), and Shepard recognized the glacial origin of these generally coarsegrained sediments. Detailed studies of the sediments 

of Georges Bank were made by Shepard, Trefethen, 

and Cohee (1934), Wigley (1961), and Rvachev (1965). 

Shepard and his coworkers believed that the bank 

owed much of its present form to glaciation. McMaster 

and Garrison (1966) described the mineral composition of some shelf sediments off southern New England. Neal (1964) examined the mineral content of 

some shelf and deep-sea sands (mostly deep-sea) off 

the east coast of the United States. Other papers 

which describe the local structure, sediment texture, 

and stratigraphy were summarized by Uchupi (1963). 

FIELDWORK 

Two sets of surface samples were used to study the 

mineral composition of the sediments. One set, collected by the U.S. Bureau of Commercial Fisheries 

Biological Laboratory at Woods Hole, Mass., was 

obtained with a Smith-Mcintyre grab (Smith and 

Mcintyre, 1954); this sampler recovers sediment from 

a 0.1 square-meter area. The second set of samples, 

collected by the Woods Hole Oceanographic Institution, was obtained with a Campbell grab,' a device 

which samples a 0.6 sq-m area. A camera and a strobe 

light were mounted inside the Campbell grab to photograph the bottom when the sampler was 1 m above 

it (Emery, Merrill, and Trumbull, 1965). 

METHODS OF STUDY 

Approximately 1,000 bottom samples have been 

collected from the continental margin between southern Nova Scotia and northern New Jersey. For this 

study 229 samples were chosen and assumed to be 

representative of the area. 

The sediments were sieved to obtain the sand fraction. 

Bromoform (specific gravity= 2.89) was used to separate the sand into light and heavy components. A binocular microscope was used to identify 100 grains of the 

light fraction from each sample. The heavy fraction was 

then mounted in Aroclor (refractive index= 1.66) and 

identified with a petrographic microscope. Mineral 

frequency was obtained by a line-counting method. 

Grains larger than 0.5 mm were not included in the 

mineral mount; the percentage of grains thus excluded 

rarely amounted to more than a few percent. Micaceous 

minerals were not counted because their flaky shape 

caused an incomplete separation from light mineral 

grains. The heavy minerals were divided into three, 

groups: (1) nonopaque minerals, (2) opaque minerals, 

and (3) altered minerals 

Counts of heavy mineral grains were made until a 

total of 100 nonopaque grains was reached. Nonopaque 

grains ranged from 9.7 to 82 percent of the total heavy 

component, and, therefore, counts ranged from 120 to 

more than 1,000 grains. For most slides the count was 

about 200 grains. 

Replicate counts made on 30 slides showed good 

agreement. The first 10 replicates were tested for independence by a rank-correlation test (Tate and Clelland, 

1957), and the hypothesis of independence between the 

replicates was rejected at the 0.10 level of significance. 

ACKNOWLEDGMENTS 

Throughout this report considerable use has been 

made of data collected by other workers. Special thanks 

are due: J. S. Schlee, U.S. Geological Survey, for 

textural data; James V. A. Trumbull, U.S. Geological 

Survey, for coarse-fraction data; and Elazar Uchupi, 

Woods Hole Oceanographic Institution, for topographic 

and structural information. Many of the ideas presented 

in this paper have been shaped in discussion with the 

following colleagues on the marine geology program: 

Elazar Uchupi, R. M. Pratt, K. 0. Emery, and P. McFarlin, Woods Hole Oceanographic Institution; and 

J. S. Schlee, J. C. Hathaway, James V. A. Trumbull, 
170o 

1()." 

11-

al9o 

1($ 

CJC"'~" 

(oq;. al9o 

Nantucket 

Island 

c~~# ~~ ~0 

~ " 170o 

25 0 25 50 75 100 KILOMETERS ~4>~/ 

DEPTH CONTOURS, IN METERS 

(o ~ 

:O'Dco\ 

pe11-o 

River 

Roseway 

Bank 

~~;?( ~~/~~'1;-

A~"-.~/~~'1;-"" 

i!'-~" u ... q, 

q,4. ~ .. 

oiS 

v~o 

FIGURE !.-General bathymetry of area between southern Nova Scotia and northern New Jersey. Contours, in meters below sea level. 

~~0 

rori 

~ 

~ 

:s: 

~ !:0 

E: 

... r:Jl 

c 

~ 

~ 

~ 

~ 

~~ 

~ 

~ 

UJ. 

c 

0 

t-3 

> 

~ 

~ ~ 

l;j 

!:0 

~ ~ 

~ 
G4 ATLANTIC CONTINENTAL SHELF AND SLOPE OF THE UNITED STATES 

and R. H. Meade, U.S. Geological Survey. R. H. 

Meade, K. 0. Emery, and J. S. Schlee reviewed the 

manuscript. J. R. Frothingham, Jr., Woods Hole 

Oceanographic Institution, helped with data reduction. 

·Jean English of the Computer Center, Woods Hole 

Oceanographic Institution, aided in electronic data 

processing. 

MINERAL COMPONENTS AND THEIR AREAL 

DISTRIBUTION 

HEAVY MINERALS 

Heavy minerals generally constitute a small part 

of the sand fraction. Their weight percentages range 

from 0.05 to 19.9 percent; most values are between 

1 and 4 percent. Areas with more than 6 percent 

heavy minerals include the inner shelf adjacent to 

northwestern Maine off southwestern Nova Scotia., 

the outer continental shelf off Long Island, and Long 

Island Sound. Areas with less than 2 percent heavy 

minerals include Georges Bank, Nantucket Shoals, 

and parts of the continental slope. 

NONOPAQUE HEAVY MINERALS 

Table 1 gives the 27 nonopaque heavy minerals 

that have been identified; this is a minimum number 

because several species are possible within a single 

mineral class. For example, garnets occurred as clear 

grains, orange-red grains (possibly almandite), and 

grains with various degrees of pink coloring (possibly 

spessartite). Likewise, the general category of amphiboles includes tremolite, actinolite, and hornblende. 

TABLE 1.-N onopaque heavy minerals in sediments of the continental margin between southern Nova Scotia and northern New 

Jersey 

Aegirite 

Aegirine-augite 

Amphiboles 

Anatase 

Andalusite 

Apatite 

Augite 

Bronzite 

Brookite 

Cassiterite 

Clinozoisite 

Corundum 

Dumortierite 

Epidote 

Garnet 

Hypersthene 

Kyanite 

Monazite 

Olivine 

Rutile 

Sillimanite 

Staurolite 

Spinel 

Titanite 

Tourmaline 

Zircon 

Zoisite 

Five minerals-garnet, amphiboles, augite, epidote, 

and staurolite-constitute more than 75 percent of 

the nonopaque heavy minerals (table 2). The general 

description of the common nonopaque heavy minerals 

is given in table 3, and the areal distribution of some 

of the minerals is shown in figures 2-5. 

Among the less common heavy minerals are zoisite, 

rutile, and apatite. These minerals rarely constitute 

more than 3 percent of the nonopaque heavy-mineral 

component and generally do not have any regional 

concentrations. Foraminiferal tests, filled with pyrite, 

accumulated in the heavy fraction. These tests are 

found mainly on the continental rise south of Long 

Island. 

TABLE 2.-Mineral frequency (number percent) of the common nonopaque heavy minerals in the sediments of the continental 

margin between southern Nova Scotia and northern New Jersey 

Mineral Percentage oc- currence in 

samples 

Garnet. ___________________________ _ Amphiboles. ______________________ _ Augite _____________________________ _ 

Epidote.---- ___________________ ---_ Tourmaline ________________________ _ Staurolite __________________________ _ Hypersthene. _____________________ _ Andalusite. ____________ --- _____ --- _ Titanite. __________________________ _ Zircon. ____________________________ _ Kyanite. __________________________ _ Slllimanite. _______________________ _ 

100 

100 

97.3 

97 

95 

94.6 

89.1 

85 

82.8 

79.6 

72.3 

69.1 

Mean percent- Range of perage of heavy- centage mineral fraction 

26.9 

24.0 

9. 9 8. 0 

5.4 

9. 0 4.0 

3. 2 2.1 

3. 2 

1.5 

1. 9 

2-72 

2-63 

0-48 

0-31 

0-29 

0-30 

0-30 

0-16 

0-15 

0-17 

·o-u 

0-8 

OPAQUE HEAVY MINERALS 

In many samples, opaque heavy minerals are the 

dominant constituent of the heavy separate. Thick 

grains such as hornblende sometimes can be confused 

with opaque minerals, but the cleavage form and ·the 

translucent edges of the grains can aid in their identification as nonopaque grains. 

Opaque minerals are abundant on Georges Bank, 

parts of Northeast Channel, and Nantucket Shoals 

(fig. 6A). This concentration extends from the Georges 

Bank area to parts of the continental slope and rise. 

Other areas of abundance include parts of the Gulf of 

Maine, the inner shelf off Rhode Island and Cape Cod, 

and off New York City. 

The individual minerals of the opaque class were not 

studied in detail. Examination of selected slides showed 

common opaque minerals such as leucoxene, magnetite, 

ilmenite, hematite, and limonite. 

ALTERED HEAVY MINERALS 

Many mineral grains could not be positively identified because they were highly altered. These minerals 

have been grouped together as "altered minerals." 

They have various shapes and commonly exhibit some 

degree of rounding; they also generally lack extinction. 

By using the criteria of color and shape, many of the 

altered minerals resemble amphiboles, pyroxenes, and 

epidotes. 

Altered minerals are abundant in the northern part 

of the Gulf of Maine and in individual samples from 

other parts of the gulf. Georges Bank and the Long 

Island shelf have relatively small amounts of altered 

minerals (fig. 6B). 

The distribution of altered minerals is similar to that 

of the more easily altered nonopaque heavy mineralsaugite, hypersthene, and amphiboles. This association 
HEAVY MINERALS, CONTINENTAL MARGIN, NOVA SCOTIA TO NEW JERSEY G5 

TABLE 3.-Description of the common nonopaque heavy minerals in the sediments of the continental margin between southern Nova Scotia 

and northern New Jersey 

Mineral Varieties Form Alteration Areas of abundance Other comments 

Garnet_ ____ __ -·_ Mainly colorless; some Commonz subrounded Little Indication of Georges Bank, outer shelf off Nova Some sharply angular fragpink, red, and orange or roun ed. weathering or etching. Scotia; Long Island shelf; orange ments with conchoidal 

varieties. garnet common off New Jersey fractures. 

(fig. 2A). 

Amphiboles ______ Mainly green hornblende, Generally elongated Usually unaltered a!- Inner shelf off Maine; off Boston; Some amp,hibole grains are some brown horn- prisms; some rounded though weathering isolated parts of the Gulf of Maine; so deep y colored that 

blende; rare tremolite; grains. effects are sometimes on parts of the outer shelf and they appear almost opaque. 

actinolite, and glauco- noticeable. slo)e; in Long Island Sound (fig. phane. 2B. 

Augite ___________ Mainly deep green or Commonly irregularly Some solution effects Northern part of the Gulf of Maine A colorless or pale-green 

brown augite. shaped anhedral grains; have produced needle- and the southern part of the Bay dlopside variety Is also some grains have pris- like ends to the grains. of Fundy (fig. 3A). present. matte cleavage. Weathered and cor- roded grains are com- mon. 

Epidote __________ Commonly yellow- Generally irregular grains Some grains show con- Near Cape Cod; on the Inner shelf Yellow-green grains have a green; some colorless. with some rounding. slderable weathering off Rhode Island; on the conti- distinct but weak pleoand alteration. nental slope and rise south and chroism. 

southwest of Georges Bank (fig. 3B). 

Tourmaline _____ _ Mainly brown; occasional Short prismatic grains; No indication of weather- Around Cape Cod and southern Pink tourmaline occurs pink or blue grains. some irregular or well- ing or alteration. Massachusetts; Nantucket Shoals; west of Nova Scotia and 

rounded oval grains. parts of Georges Bank (fig. 4A). off Rhode Island; blue occurs on Georges Bank 

and in parts of the Gulf of 

Maine. 

Staurolite ___ _____ Mainly yellow grains Irregular grains with Little indication of From Cape Cod across Nantucket Typical "Swiss-cheese" 

with distinct pleo- conchoidal or semi- weathering. Shoals and Georges Bank to the appearance, due to chroism. conchoidal fractures. southern and western r,arts of weathering out of incluNova Scotia; off Long Is and and sions, was common to 

New Jersey (fig. 4 B). many grains. 

Hypersthene _____ Pale ~nk to green with Generally as prismatic Weathering common in Along the northernmost coast of Many grains have thin 

stri ing pleochroism; grains. graini from Maine Maine and the southern part of platelike Inclusions some colorless enstatite. coast and Bay of Fun- the Bay of Fundy; off Northeast (schiller structure). 

~~[~~~J~~ ~~~th- Channel; on the outer shelf and 

slope off New Jersey (fig. 5A). 

east Channel. 

Andalusite _______ Colorless to pale pink _____ Rounded or Irregular Slight Indication of In the nearshore re~lon off eastern Inclusions are common. grains. weathering. Maine; off parts o Cape Cod; on parts of Georges Bank (fig. 5B). 

Titanite. ___ . ___ - Colorless. ____________ _____ Anhedral grains ______ _____ No indication of weather- Generally In very small quantities; Grains have extreme dislng. a local area of abundance on persion. 

Georges Bank. 

Zircon.------ ---- Colorless. _________________ Euhedral c~stals with Little Indication of Georges Bank and parts of the Gulf Some irregular and rounded 

prismatic abit. weathering. of Maine. grains. 

Kyanite_. ------ Colorless. ________________ . Elongate rectangular Little indication of Generally In very small quantities; Some grains are rounded. 

with conspicuous weathering. local areas of abundance along cleavage. south shore of Long Island and 

parts of the Gulf of Maine. 

Sillimanite ••..... Colorless __ ____ ____ ___ ----- Short irregular prisms ___ _ - Little indication of Generally In very small ~uantities; 

weathering. local areas of abun ance on Georges Bank, off Cape Cod, and 

in shallow areas of the Gulf of 

Maine. 

may suggest a partial removal of these nonopaque 

heavy minerals from the environment. 

amphiboles, epidote, augite, and altered grains are more 

prevalent in the finer sized sediments. 

EFFECTS OF GRAIN SIZE 

The possible relationship between median grain size 

of the sand fraction and the percentage occurrence of 

individual heavy minerals was tested using a linear 

regression procedure. For many heavy minerals, grain 

size and mineral composition seem to be related (table 

4). Garnet, staurolite, andalusite, titanite, and opaque 

grains are more common in the coarser sized sediments; 

377-278 0-70--2 

Several heavy minerals have an areal distribution 

pattern similar to that of the median grain size (fig. 7). 

The dependence of mineral composition on grain size 

shows the difficulty of using an individual mineral type 

as an indicator of source. A better procedure is to 

consider the entire mineral assemblage; however, even 

when one does this, variations in size may obscure 

differences between assemblages. This effect will be 

reintroduced in the section on heavy-mineral associations. 
a&. I 

"o- I 

A 

25 0 25· 50 75 100 KILOMETERS U......w.J.--L--'--_j__J 

DEPTH CONTOURS, IN METERS 

::::::::::::::::~::::::::::~::::::mstG1'K1tK:::u::::::~:::::n::::iff:::::mr:~:::~mrrr:::::m:::::r::::::~::::t~E±HKII~!i! llil'~m :m!' ~! 11 ;;::m:mm:m::;,,H:mm:::::H,::,:~::::::::::: ~~~ 

~~~w:yrw:::n:::::::n:::::::::::::::n::n::::::m '·'\· 

"'?) a&. b 10 

/ 

'ii"o. 

X 

10.;. 

EXPLANATION 

r:::;::=J~l~-

• 

Sample location 

"'..:>. 

0 

0') 

> >'3 

t"' 

..... 

~ c 

c 

0 

~ 

!2l 

l':1 

z 

>'3 

g:; 

~ ~ 

~ tl 

Ul 

t"' 

0 

'tl 

l':1 

0 

"!! 

I ~ 

'ii"'ii"o ~ .... 

>'3 

l':1 

tl 

I Ul 

J ".-c Ul 

~ 
25 0 25 50 75 100 KILOMETERS 

DEPTH CONTOURS, IN METERS 

"'o. 1·-~nLH~ "~ '4ill:: mm~ y "' ) ~<'- J~t~':r:. ~ I > 

'-\ ./ I 

::mm::: :m0·::,:~~ ~/ "\ Boston~:::::: :::: :::::: millnill1W K: i·.~t~ ,/ r!c ·~ \ r:;<"' 

" 

'\1\ ~:~~: :: ~: :::: ~:m ~: ~, :~ ~~~:~ ~::~~ -z~tt:I&Z~~ ~uzm~:: ~: ~\~=~=~=~ ~=~= =~=~=~=~=~=~=~=~= =~=~=~=~=~s ::::::~::: u:n::::: :: t:I~i~ n' :: ::~:: :: ::~ ~!~ ~: ~~ Zf % (S,~ I 

<9. I :::: ·:: :: ::::: ::: ::::~~'fmti~ ~~~vt~~~ f~~~~ ~~~~ w~~~ ~~~~r ~~~~~ r~~~t~ x~~uJ: ~~~~~~j ~~~~~~~~ t~ ~~~ ~r~~::::' ~~·~ 

"~I ""' ~u.::lzr~ :' ::~~~ ~~ :: :~ ~~ ~~n~ ~~ ~~~ n~ ~:: ~~~~~ ::~: H'' "\ / . """"' v"'' "' ~ 

X V1 "'" B 

r~vu~------- / ~ ~ 

/ 

ro<b ~<9. rO (jj '~~'o. ro.;. '~~'<?. 

FIGURE 2.-Distribution of garnet (A) and amphiboles (B). Included in the amphiboles are tremolite, actinolite, glaucophane, and, most commonly, green 

hornblendes. Mineral percentages are an approximation to area or volume percentage of the nonopaque part of the total heavy-mineral fraction. 

I ~ 

I ~ 

Is: 

z 

l".l 

l:C 

~ ~fll 

c 

0 

z 

t-3 

~ 

~ > t' 

I ~ l:C 

0 

~z 

z 

0 

I ~ 

rJl 

c 

0 

'll'll'o ~ 

;s 

~ 

\roi ~ 

~ 

l".l 

l:C 

~ ><l 

I 

e 
-YO>. 

c) "\ 

A 

ct ~ -YO>. 

• 

~ ~ 

• 

'11'o. 

25 0 25 50 75 100 KILOMETERS ~___J_ _ __j__j _ __l 

DEPTH CONTOURS, IN METERS 

r.i 

EXPLANATION 

Percent 

0-15 

6-30 

• 

Sample location 

"'~. 

~ 

> >'3 

t< 

~ >'3 

...... 

C".l 

C".l 

0 

z 

>'3 

z 

l"l 

z 

>'3 

~ 

~ ~ 

~ t:l 

1:/) 

t< 

0 

"d 

l"l 

0 

"'J 

>'3 

1:11 

l"l 

c 

z '11''11' • ...... 

>'3 

l"l 

t:l 

j ·' 1:/) 

l"l 

~ 1:/) 
~~'o, 

1 1>.0 

'\1 

J>O>o 

0 1 

B 

<b l(j J>O>, " ro ~~'o , 

25 0 25 50 75 100 Kl LOMETERS l.u...Lu____j______t_ _ ___L____l 

DEPTH CONTOURS, IN METERS 

,,;; 

EXPLANATION 

Percent 

• 

Sample location 

v<?o 

FIGURE 3.-Distribution of augite (A) and epidote (B). Mineral percentages are an approximation to area or volume percentage of the nonopaque part of 

the total heavy-mineral fraction. 

l1'l1'o 

ro1 

~ 

s 

~ ~ 

~ !fl 

0 

0 

~ 

~ 

Cl 

~ 

~z 

~ 

~ 

rFl 

0 

0 

j 

> 

::l 

~ 

::f1 

t;j 

~ 

~ ~ 

~ 
"'&. 

A 

<b 10 "'&. ~ 10 '11'o. 

25 0 25 50 75 100 Kl LOMETERS 

DEPTH CONTOURS, IN METERS 

10.;. 

0-5 

6-10 

11-15 

>15 

• Sample location 

'11'"'· 

'11''11'o 

ro1-

0 

.... 

0 

I 

C".l 

I 

~ 

! 

~ 

~ ~ 

~ l":J 

~ 

~ 

~ ~ 

; 

Ul 
1()." 

'\1 

.YO>. 

1<$ 

B 

<6 " ..;><9. ~ 10 '11'o. 

25 0 25 50 75 100 KILOMETERS 

~1·--'---'---'--' 

DEPTH CONTOURS, IN METERS 

!o.;. '11'..;>. 

FIGURE 4.-Distribution of tourmaline (A) and staurolite (B). Mineral percentages are an approximation to area or volume percentage of the nonopaque 

part of the total heavy-mineral fraction. 

,,_ 

rori-

~ 

$ 

~ 

j 

I 

~ 

~ 

-~ 

~ 

~ 

~ 

~ 

~ 

~ 

~ 

~ l:d 

~ ><l 

0 

...... 

...... 
G12 

(/) 

a:: 

w 

..... 

w 

:2: 

0 

_J 

"' (/) 

a:: 

~ w ~ 

"' :2: " z 

0 . 

"' 

0 

N "' 

ATLANTIC CONTINENTAL SHELF AND SLOPE OF THE UNITED STATES 

•o 

<"" 
.., 

.... 

.... 

~ 00 

1: 

I vo. 

'\c." 

'\1-

.;><9. 

<:;) 1 

B 

<b b .;><9. 

1/ ,)' 

,~ 

-~ . ~~ 

" 0 

1/-. 

ocP '"·"··" 

25 0 25 50 75 100 KI LOMETERS I 

DEPTH CONTOURS, IN METERS 

~4.>c,,' 

c,~;'ff IV'Y//'Y"tA~--,'~;/,;; ~~ ~ 

~ 

..... ,(; ... ~ ""'~ . 

REg__.~ 

p#/4 

\ ;..,""t 

-·--.......__-vooo.-......._ ___ ~. 

·--............ "·---........._, 

11'o • .,t> . 

FIGURE 5.-Distribution of hypersthene (A) and andalusite (B). Mineral percentages are an approximation to area or volume percentage of the nonopaque 

part of the total heavy-mineral fraction. 

11'11'o 

~ 

~ 

~ t>:J 

~ 

~ 5'J 

~ 

~ 

~ 

~ ~ 

0 

~ 

~ 

:; 

UJ 

0 

0 

~ 

~ 

0 ~ ro'~- ~ 

~ ~ 

~ 

>< 

0 

~ 

c..;! 
vO, 

'\1 

"'<~>, 

c) '\ 

A 

ro<b "'&, rorO ~<'o, 

25 0 25 50 75 100 KILOMETERS L.u...w..J. ___ _L_ ___ j __ J_ __ ___j 

DEPTH CONTOURS, IN METE RS 

ro.,; 

Percent 

1

0.0-15.0 

15.1-30.0 

~4~45.0 

• Sample location 

17._:>, 

li'li'o 

rei 

0 

...... 

~ 

~ 

0 

~ 0 

0 

~ t'J 

z 

~ 

~ ~ 

~ t:l 

~ 0 

"d 

t'J 

0 

l:j 

~ t'J 

d 

~ t-3 

t'J 

t:l 

w 

~ t'J 

w 
B 

ro<b "'<S>. 4) 

10 '"'o. 

25 0 25 50 75 100 KILOMETERS u_._._,_l_ _ ____j 

DEPTH CONTOURS, IN METER S 

t: (o '"'"'· FIGURE B.-Distribution of opaque heavy minerals (A) and altered heavy minerals (B), in percentage of total heavy minerals. 

~ 

~ 

::0 

~ ~ 511 

C) 

0 

~ ~ > t"' 

~ 

~ 

z 

~ rJl 

C) 

0 

8 

..... 

> ....... ~ 

~ 

~ 

rori. c.. 

tr.l 

::0 

~ ...: 

0 

.... 

~ 
G16 ATLANTIC CONTINENTAL SHELF . AND SLOPE OF THE UNITED STATES 

TABLE 4.-Relations between heavy-mineral percentage and median 

size of the sand fraction 

[Correlation coefficient: for 219 samples; a positive correlation indicates that the min- e~al species is more common in the finer grain sizes (higher phi values). Md.p: median 

dmmeter, !n p~i units; phi is the negative logarithm to the base 2 of the grain size, 

expressed m millimeters] 

Mineral 

Amphiboles. _______ ___ ...... ___ . __ . Epidote. _________ __ ________ . .... __ _ Augite ....... ______________________ _ 

Hypersthene._ .. _ ..... _._ ....... _. _ Titanite. ____ ...... __ ... ... ______ .. _ Tourmaline .......... ______ ........ _ Zircon. ___ ._ ... _____ ....... __ .... __ _ Garnet._ •......... _ .. ___ .. _ .. _._ .. . Staurolite ........ ______ ............ . Kyanite. __ ..... __ -------.......... . Andalusite •. .. _ ... __ ... _ .. __ ... __ _ _ Sillimanite. ___ ._ .. ____ .... ____ .. __ . Oflaque grains .. ___________________ _ 

A tered grains __ .......... ____ ...... 

C orrela tlon 

coefficient 

0. 507 

. 376 

. 237 

. 063 

-.148 

- . 102 

.023 

-.567 

-.398 

-.019 

- . 156 

. 117 -.268 

. 260 

Significant 

at 95 percent 

level 

Yes ......... .. Yes ......... .. Yes .......... . No ........... . Yes ......... .. No ___________ _ 

No .. ___ ...... _ Yes .......... _ Yes ......... .. No .......... .. Yes __________ _ 

No .......... .. Yes .. __ ...... . Yes ......... .. 

LIGHT MINERALS 

Regression 

function, 

in percent 

7. 85+6. 27 Md<t> 2. 73+ l. 84 Md.p 4. 27+2.17 Md<i> 3. 43+0. 27 Md<i> 

2. 89-0. 27 Md<l> 6. 38-0. 43 Md</> 27. 85+0. 69 Md</> 46. 18-7. 28 Md</> 15.07-2.34 Md<l> 

1. 62-0. 03 Md<l> 

4. 23-0. 41 Md<i> l. 29+0. 21 Md<i> 45. 32-3. 39 Md<l> 

8. 93+3. 60 Md<l> 

Light fractions were examined for percentage of 

terrigenous material, glauconite, and biogenous material. The terrigenous contribution includes quartz, 

feldspar, rock fragments, and mica. Biogenous material, 

in lesser quantities than terrigenous material, can be 

divided into foraminifers, radiolarians, diatoms, sponge 

spicules, other shell fragments, and fecal pellets. 

TERRIGENOUS MATERIAL 

Quartz and feldspar together are the major components of the light fraction. The relative distribution 

of these two minerals is being studied by J. C. Hathaway 

and P. F. McFarlin (oral commun., 1968), who are 

using X-ray determinations for a quantitative estimate 

of quartz and feldspar. 

Quartz and feldspar are abundant (greater than 75 

percent of the light fraction) over most of the area 

(fig. 8A). Small quantities of these minerals occur 

only on the outer continental slope and continental 

rise south of Georges Bank and Long Island, where 

biogenous material is more abundant. Intermediate 

amounts of quartz and feldspar occur in Long Island 

Sound, on parts of the inner continental shelf off New 

Jersey, Massachusetts, Maine, and Nova Scotia, and 

in the outer part of Northeast Channel. In these areas 

(except for Northeast Channel) are large quantities 

of rock fragments, mica, or glauconite. Biogenous 

material is present in the outer part of Northeast 

Channel. 

Many of the quartz and feldspar grains are stained 

red or orange, apparently by a coating of iron oxide. 

These stained grains are most common in the Gulf of 

Maine and Bay of Fundy (fig. 8B) and are relatively 

rare along most parts of the inner continental shelf, on 

the continental rise and slope, and on parts of Georges 

Bank. 

Rock fragments are relatively abundant in the northern parts of the Gulf of Maine, in the Bay of Fundy, 

in some of the river samples, in isolated parts of the 

continental shelf west of Georges Bank, and in Long 

Island Sound. 

The black rock fragments in many of the rivers and 

in Long Island Sound are apparently cinders or coal 

introduced into the area by ships or industry. Sawdust 

and wood fiber in some of the river sediments are 

probably from pulp mills that discharge wastes into the 

nvers. 

Some rock fragments in the Bay of Fundy are sandstones and may come from the Triassic red sandstones 

and siltstones of Nova Scotia. Rock fragments are not 

common on the southwestern part of Georges Bank and 

Nantucket Shoals; where found, they usually are green. 

Mica, mainly biotite, is abundant off the Kennebec 

River, in parts of Long Island Sound, and in one area 

on the continental slope off Long Island. 

GLAUCONITE 

Glauconite occurs in minor amounts on Georges 

Bank, the Long Island Shelf, in parts of Northeast 

Channel, and in the Gulf of Maine. Glauconite is abundant only off the New Jersey coast; this concentration 

probably represents local reworking of Tertiary or 

Cretaceous glauconite-rich deposits (J. V. A. Trumbull, 

oral commun., 1967). 

BIOGENOUS MATERIAL 

Biogenous material is abundant mainly on the 

continental slope and rise south of Georges Bank. The 

concentration of biogenous material abruptly decreases 

above the 2,000-m contour line (fig. 8A), a depth that 

marks the approximate base of the continental slope. 

This transition suggests that the decrease in biogenous 

material may be due to dilution by coarse terrigenous 

material rather than to any decrease in biological 

productivity in this area. 

Planktonic foraminifers and shell fragments dominate 

the biogenous fraction. The shell fragments are difficult 

to identify and were not separated into individual types. 

Radiolarians, diatoms, and sponge spicules are more 

abundant in the deeper water sediments from the 

continental rise. 

Shell fragments are concentrated locally near 

Northeast Channel. Other local concentrations of biogenous material are in the Gulf of Maine and on parts 

of the continental shelf. Fecal Pellets occur in two 

samples, one from the Scotian Shelf and the other from 

Georges Bank. 
25 0 25 50 75 100 KILOMETERS l..__.~l _ ___J___J_ ___ _L ____ j 

DEPTH CON TOURS, IN METERS 

1-- ~'</l \_, "o. I"··A::l::H~'o,.,~ ''\m~m:i!~ ~')' '\. ) C..'~- J ~::::::;~'"::r__ ~ // 

7 

\ \ 

1 r,• 1::~t;:;:;)l[H HHH~"'Q' ~\/4!).! <fi'~~/ ",. BoHton ___ ~ ('(1-

('00 l\ 

/ / ......... 

,11m: :~m::: :::m:: ,:::: ,,,:,; ,0 !W:ii!ii! !l il!:ii ~ltw::::::>'t(Ui!ii~uwm~:~::~~~::~~'l:::::: :: ~:::::: :::::::::::~:::: :\i:Jii~iii~i~iifrt: i:nY.t~~~ii!i!iii :i i:~mLlili ;L :::::::~:>C% (s~ I I 

a&. I ·:::: :m:: :mm~%18 :::::mmm::::: fl;;:ittnstrtNt&:t:::::~~::x:::::::x:::::~:::::::::::::::::::::: ::::~:: :::::::::::=:=:=:=:=:=:=:::::x :::~:: :::::M::: :::: :: ~l''''''''~''''''''~:~''' :'u'"'· --J~"l--~·~~""',._, 

11''57. 

1° I ~---------'--40 / / oo~- .o / 

2.0-4.0 o-2 ¢ <P rm~r025mm ··~~~~~~~;~; 

·· ·.·. 

0.25-0.062 mm / r 

4.0-6.0 <P (:i:)) 0.062- 0.015 mm 

>6.0 </> lliiil'lill - ---

• 

Sample location 

rc;cb "'&. rO ro '11'o. rot; '17"'· 

FIGURE 7.-Distribution of median grain sizes of material finer than 2 mm in the sediments. Data from J. S. Schlee. 

~ 

~ 

~ 

z 

l':l 

~ 

> t" 

~rp 

() 

0 

z 

1-:3 

...... 

~ z 

1-:3 

~ 

~ 

> 

~ 

0 

~z 

z 

0 

~ 

rp 

C".l 

0 

1-:3 

...... 

> 

~ 

z 

l':l 

~ 

~ 

l':l 

~ 

~ ~ 

0 

...... 

~ 
J><9o 

A 

<b "' J><9o 4j ~ ... o. 

25 0 25 50 75 100 KILOMETERS L...w....L._ __ _L__i _ __J ___ I 

DEPTH CONTOURS, IN METERS 

ro.;. 

EXPLANATION 

Percent 

-0-25 

26-50 

51-75 

• 

Sample location 

...,. 

0 

-

ao 

c 

~ c 

I 

~ 

! 

tj 

~ 

~ 

~ 

~ 

~ 

~ ....... t;j 

t::l 

ro1- l7l 

~ 
25 0 25 50 75 100 KILOMETERS 

u._._._..l _j_--.J 

DEPTH CONTOURS, IN METERS 

"i l:r~:~~~:~:r~:}~?r:~:~:~:~:~:~:r~:~:~f~~~~~::n&u~:~~u~~~~:~~~:~}:::::::::::::~::~::!:~:wnn:~~m~t¥w~;;;~ ~illwu :;:: ;:~mfuku:;:~~::::;:~~;:~;~;;:~;urm:z- c:::""~ I 

-Yo>. I ::::: ::::::r:::::ut:t:::::::: :: :: :~: :::i::::~:~:tt®tmi~Elli::::::m:::u~:::uf0:::::m::::::::w:~::nf:m~::l~J::::::::m::::::::::::::::::::::::t:~t::::::. ~('/~~ 

"~I 

B 

'~~~t}:0:{{{:::::::: :::::::{{{{:}~{:%{{{{:}}i:f{Y 

bqj -Y<l'o ~ !0 'ilo. 

···::;:;:;:::::::::::::::::····· 

~ b 

'"/ ."" ·"-., 

v.,. 

~ 

~ 

a:: 

z 

l".l 

::>::l 

ffi 

('") 

0 

z 

~ l".l 

z 

>-3 

> t' 

I ~ ::>::l 

0 

...... 

~z 

z 

0 

I < 

> 

'(fJ 

('") 

0 

>-3 

'T. ~ 'ito ~ 

~ 

14:>1: ~ 

c:.., 

l".l 

::>::l 

~ 

>< 

FIGURE 8.-A, Distribution of quartz and feldspar, in percentage of light-mineral fraction. Areas with values of 50 percent or less on the continental slope are 

areas of high quantities of biogenous material. B, Distribution of iron-stained quartz and feldspar, in percentage of total quartz and feldspar. 0 

...... 

c:o 
G20 ATLANTIC CONTINENTAL .SHELF AND SLOPE OF THE UNITED STATES 

SOURCE AREAS AND SUPPLY OF SEDIMENTS 

GENERAL GEOLOGY OF THE SHELF AND ADJACENT 

LAND AREA 

Paleozoic, Mesozoic, and Cenozoic rocks occur along 

the eastern seaboard of the United States. The Coastal 

~lain (fig. 9) , a region of a relatively low relief, consists of undeformed or gently folded Cretaceous and 

:rerti~ry rocks. The Coastal Plain north of Cape Cod 

IS entirely submerged, and the coastal area is mainly 

Paleozoic metamorphic and intrusive igneous rocks. 

The position of the northern edge of the Coastal 

Plain has not been agreed on by geologists. Cape 

Cod, Martha's Vineyard, Nantucket, Long Island, 

and Block Island all consist primarily of glacial material underlain by Coastal Plain sediments (Thornbury, 

1965). The general difference in topography and geology 

of the islands and Cape Cod from the neighboring 

generally crystalline provinces of the adjacent mainland suggests that these areas mark the northern edge 

of the Coastal Plain; to the east the Coastal Plain 

rocks continue submerged beneath the continental 

shelf (Emery and Uchupi, 1965; Uchupi and Emery 

1967). ' 

Seismic refraction studies have shown a thick sequence of sediments, presumably Mesozoic and Cenozoic Coastal Plain material, off the northeastern 

coast of the United States (Drake and others, 1959). 

~oa~tal Plain sediments, however, are generally lackmg m the Gulf of Maine (Drake and others 1954 · 

Uchupi, 1966). ' ' 

Long Island Sound lies along an inner lowland behind a cuesta whose scarp is expressed by Long Island, Block Island, Martha's Vineyard, and Nantucket (Thornbury, 1965). Georges Bank is a submarine extension of the cuesta (Johnson 1925 · Emery 

and Uchupi, 1965). The submerged boundar; of the 

Coastal Plain has been traced into the Gulf of Maine 

(Uchupi, 1966). 

N orthea~t of New York, crystalline rocks mainly 

of Paleozmc age extend to the shoreline. These rocks 

are ~x~e~sively. folded, faulted, and metamorphosed. 

Gramtic mtrusives and volcanic rocks are common in 

the New England area. The proportion of volcanic 

rocks i~ relatively. higher in northern New England. 

Carbomferous sedimentary and volcanic rocks are 

present near Boston and Narragansett Bay and in 

the n?rt~ern ~art of New Brunswick. Fault troughs 

of TnassiC sedimentary and mafic intrusive rocks occur in the Connecticut River valley, south of New 

York, and on the northwest side of Nova Scotia. 

EFFECTS OF GLACIATION 

The effects of glaciation are apparent throughout 

New England, the Gulf of Maine, in most of New york 

including Long Island, and on parts of the Continental 

Shelf. Details of the glacial history of the New England 

region are incompletely understood. One reason is that 

most of the outer border of the glaciated area is now 

submerged; another reason is the general lack of chronology for interglacial and glacial events. It does seem, 

however, that all New England was glaciated. Drift in 

New England averages about 5 min thickness; probably 

several times as much drift, in part derived from the 

land, is offshore below sea level (Schafer and Hartshorn, 

1965). Glacial striations trend generally between south 

and east with local variations caused by topography 

(National Research Council, Division of Earth Sciences, 

1959). Most tills observed in New England are Wisconsin in age. Probably the most complete Pleistocene 

section is that on Martha's Vineyard where Kaye (1964) 

observed at least six different glacial drifts; these drifts 

are discontinuous and generally deformed by ice thrust. 

The exposed parts of Nantucket, Martha's Vineyard, 

Cape Cod, and Long Island consist of glacial moraines 

and outwash mainly of Wisconsin age (fig. 10). Some 

earlier Pleistocene formations are known from Long 

Island (Donner, 1964; Muller, 1965) and Martha's 

Vineyard (Kaye, 1964). 

In view of the considerable glacial material in New 

England and Long Island and the trend of ice transport towards areas of open ocean, it seems reasonable 

to expect glacial material in the submerged areas also. 

Within the Gulf of Maine are numerous basins and 

irregular ridges (Murray, 1947; Uchupi, 1965b), many 

of which are of glacial origin. Between some basins of 

the gulf, till-like deposits of gravel, sand, and silt have 

been found. Gravel, presumably of glacial origin, is 

found on parts of the Gulf of Maine, Georges Bank, 

and the Scotian Shelf (R. M. Pratt, oral commun., 

1966). There is little topographic or sedimentologic evidence that glaciers covered much of Georges Bank 

(Emery and Uchupi, 1965). The ice probably terminated on the nearshore slope of Georges Bank and 

deposited an outwash plain of sediments on the northern 

part of the bank. Rising sea level and exposure to 

waves and tides have reworked the sediments of 

Georges Bank and the other shallow areas (Stewart 

and Jordan, 1964). Reworking, erosion, and slumping 

have resulted in some exposures of older rocks. Tertiary 

deposits are thought to lie near the surface of Georges 

Bank (Emery and Uchupi, 1965, p. 357). Eocene, 

Miocene, and Cretaceous rocks are exposed in canyons 

and on slopes off Georges Bank (Stetson, 1949, p. 11; 

Gibson, 1965, p. 975). 

The known limit of southern glaciation seems to 

extend along Long Island as two well-defined moraines, the more northern Harbor Hill moraine and 

the Ronkonkoma moraine (fig. 10). The southern extent 
HEAVY MINERALS, CONTINENTAL MARGIN, NOVA SCOTIA TO NEW JERSEY G21 

Cretaceous-Quaternary 

~ 

Coastal Plain sediments 

Triassic sedimentary 

-

rocks containing 

some diabasic intrusive rocks and 

basaltic flows 

Paleozoic 

-

volcanic rocks 

Mesozoic, 

-

Paleozoic, and 

older intrusive rocks 

Paleozoic and older sedimentary 

and metamorphic rocks 

errimack River 

0 50 100 150 200 Kl LOM ETERS 

FIGURE 9.-Generalized geology of the land area. Data mainly from North American Geologic Map Committee (1965). 
G22 ATLANTIC CONTINENTAL SHELF AND SLOPE OF THE UNITED STATES 

LANATION 

~ Postglacial marine sediments 

Outwash sediments 

End 

-

moraine of 

Wisconsin Glaciation 

74° 

I 

I 

( 

72° 

68° 66° 

,-, 

,' \ - I -/ 

/ r.~ } 

' 

100 150 KILOMETERS I 

70° 

46° 

44° 

42° 

40° 

FIGURE 10.-Moraines, outwash sediments, and postglacial marine sediments of the land areas. Data 

from National Research Council, Division of Earth Sciences, 1959. 
HEAVY MINERALS, CONTINENTAL MARGIN, NOVA SCOTIA TO NEW JERSEY G23 

of these glacial deposits is not known. However, the 

lack of any till-like deposits or other glacial features on 

the continental shelf off Long Island suggests that either 

the glaciers probably did not reach far seaward of the 

present Long Island coastline or that subsequent reworking has removed or covered the glacial material. 

Recent investigations suggest that sea level has been 

moderately stable for the last 3,000 years in the New 

England area (Kaye and Barghoorn, 1964) and for the 

last 3,000-5,000 years for the world in general (Ourray, 

1965). 

SUPPLY OF SEDIMENTS 

The major sources of sediments on the continental 

margin are the volcanic and metamorphic rocks of 

New England and the rocks exposed on the continental 

margin itself. This material has been transported by 

several media. Glaciers have removed much material 

from the hinterland and deposited it as moraines and 

outwashes both in the emerged coastal regions (fig.10) 

and on most of the continental shelf. Glaciers have 

also removed and transported material seaward from 

the Gulf of Maine and the continental shelf. The glacial material deposited in what is now the marine 

environment has been reworked by waves and tides. 

This reworking is especially intensive and active at 

present on the shallow areas such as the Long Island 

Shelf, Georges Bank, Nantucket Shoals, and the shelf 

off southern Nova Scotia. Sediments in deeper areas 

such as the Gulf of Maine have not been reworked. 

The heavy minerals of a glacial deposit should be 

typical of the rocks and soils that the glacier has passed 

over. The mineral assemblage can be modified during 

subsequent transportation and by reworking at the 

site of deposition. 

Many rivers drain the continental areas and discharge onto the continental margin (table 5). However, 

TABLE 5.-Discharge and drainage area for the major rivers of the 

northern part of the east coast of the United States 

[Average discharge: for the decade 1951-;60, data from river mouth (C.D. Bue u.s. 

Geol. Survey, written commun., 1967)] ' 

River Average 

discharge (cum per sec) 

1691 

176 

474 

522 

114 

260 

84 

606 

108 

2 695 

46 

618 

Drainage area 

(sq mi) 

38,850 

3,419 

22,196 

24,450 

4, 481 12,976 

3,815 

29,137 

5,048 

34,618 

2,862 

33,294 

! Data from farthest downstream gaging station. 

Y Iknc0

1J!des 50 cum per sec of water diverted from upper Delaware drainage by New or tty and wasted near mouth of Hudson. 3 At mouth of Delaware Bay. 

most of these rivers do not contribute much sediment 

to the continental shelf and slope because they are 

small and also because they now enter into estuaries 

formed during the recent rise in sea level. During times 

of lowered sea level, these rivers emptied on the outer 

parts of the continental shelf. 

Heavy-mineral suites from samples from different 

rivers differ considerably (fig. 11). The differences between mineral suites are representative of small variations in source rock. For example, the volcanic minerals, 

hypersthene and augite, are more abundant in the 

northern rivers, the Kennebec and Penobscot, owing to 

the greater abundance of volcanic rocks. Metamorphic 

or intrusive source rocks are typical in the drainage 

basins of the remaining rivers. Sediment supply by 

other means, such as erosion of sea cliffs or transport by 

wind, is apparently only of local importance. 

HEAVY -MINERAL ASSOCIATIONS 

Examination of the distribution of individual heavy 

minerals (figs. 2-6) suggested several mineral associations. :rvfineral associations were established initially on 

a trial-and-error basis, depending on the dominance of 

a mineral or minerals in a particular area. 'l'he mean and 

standard deviations of percentages of the minerals 

within an association were calculated. When individual 

samples had statistics considerably different from those 

of their original association and were more similar both 

in composition and areal distribution to other samples, 

new associations were established (table 6). Grouping 

by this technique has resulted in 15 heavy-mineral 

associations that are mappable (fig. 12) and seem to 

have geologic importance. The use of 229 samples for 

such a large area (area covered by this report is 346,000 

sq km) is not adequate to define all possible associations 

accurately. However, the use of additional samples 

probably would only refine the association boundaries 

or perhaps delineate smaller groupings based on more 

subtle differences in mineral composition. 

VARIABILITY IN MINERAL COMPOSITION 

The variability within individual associations can be 

considerable, as indicated by relatively large values of 

the standard deviation around the mean (table 6). 

Van Andel (1964) discussed some causes of inhomogeneity within heavy-mineral associations. The lack of 

rigorous criteria in establishing assemblages can result 

in inadequate distinction between associations, and the 

resulting incorrect groupings would increase the variability. The small number of samples, added to. the 

errors inherent in the laboratory and sampling techniques, can also contribute to the variability. 
G24 ATLANTIC CONTINENTAL SHELF AND SLOPE OF THE UNITED STATES 

... >. Q) «< > Ill ii: ... ... ... Q) ::: Q) Q) +J > Q) > > ::l ii: en ii: ii: (.) c: :;::; en «< c: c: (.) Q) bD 0 Q) «< en c: E ~ +J 

·.: "'C c: «< «< ::l 0 ..c: «< 0:: J: (.) 1- z 0 

... ... Q) Q) > > ii: ii: c: en B Q) 

c: -.: 

«< ::l 

«< ..c: 1- (.) 

... 

Q) 

> 

ii: 

~ 

(.) 

«< 

E 

"E 

Q) 

:?! 

... 

Q) 

> 

ii: 

(.) 

Q) 

..c 

Q) 

c: 

c: 

Q) 

:::.:::: 

... 

Q) 

> 

ii: 

"5 

(.) 

en 

..c 

0 

c: 

&. 

LLI 

::::> 

0 Amphiboles 

~ 0 

z 

0 

z 

20 

~en 

~~ 40 c:~ffi 

~~ z~ 

LLI>- (.) > 60 

0:::<( 

LLILLJ 

a.. :I: 

LLI 

> 

~ 

~ ::::> 

~ 

::::> 

(.) 

80 

DISTANCE BETWEEN MOUTH OF RIVERS 

FIGURE 11.-Heavy-mineral composition of sediments from major rivers between northern New Jersey and northern Maine. 

Variations in the composition of sediment supplied 

to the area is a cause of variability both between and 

within associations. Mineral composition varies significantly from one river to the next (fig. 11). 

Removal of unstable minerals by reworking and 

mineral abrasion can change mineral proportions. 

Weathering may also be an important process since most 

of the shelf area was above sea level during parts of 

the last ice age. The occurrence of large percentages 

of altered grains (fig. 6B) in the sheltered Gulf of Maine 

area suggests some stage of selective removal of unstable minerals. An alternative hypothesis is that the 

distribution of altered minerals is an effect of source 

rock type. However, in the shallow areas exposed to 

waves and currents, such as Georges Bank and the Long 

Island Shelf, altered minerals are relatively rare. This 

seems to indicate that the processes causing removal 

of unstable components are more complete in these areas. 

Another cause of variability within the associations 

may be differences in grain size. The effects of grain 

size on the mineral percentages of all the samples 

have been previously discussed (table 4). The relation 

of median grain size of the sand fraction to the percentage 

occurrence of individual minerals within the different 

associations has been tested with a linear regression 

procedure (table 7). The common heavy minerals 

in each association generally do not have a significant 

correlation with grain size, and only in a few situations 

can variations in grain size account for differences 

between associations. One example of this size effect 

is the possible similarity between fine-grained sediment 

from the Georges Bank garnet province and sediment 

from the mixed amphibole-garnet association or Gulf 

of Maine-Georges Bank complex. In most instances, 

however, size effects do not account for differences 

between the associations. Thus the influence of grain 

size on the mineral composition of an assemblage 

is minor, and other factors such as source and transportational and depositional history control the composition of the assemblage. 

SOURCE AND DISPERSAL OF SEDIMENTS 

GULF OF MAINE-GEORGES BANK AREA 

Three nearshore provinces (Penobscot amphibole, 

Kennebec amphibole, and Merrimack garnet) near 

river mouths in the Gulf of Maine (fig. 12) have heavymineral compositions similar to those of the corresponding rivers (fig. 13). The mineral composition of the 

river sediments generally reflects the composition of 

their drainage areas. An igneous intrusive source is 

indicated for the Kennebec and Penobscot River sediments. The relatively large quantity of the volcanic 

minerals, augite and hypersthene, in the Penobscot (fig. 

14) apparently come from the volcanic rocks in the 

upper parts of the valley of this river (fig. 9). A meta-

• 
'\1 

,Y&o 

'\0 

,--::;·>--,_- "-, /" ·<t'<~/ /' f -. F.i-t'er ' ----~j ~;_./ / /'\ "' / 1

r-../ 

/--- _/;,c ' ~ }, / /f ,,, <>'1-'11~-~-/'-.. / '- :-;,. / 

_., ( ~'!Jo.\' "" ;-:::./ '- &/ 

• 

• 

(\\0 ' - / '' ~ .. ~/ I v,\' / "' ~'} / 

,I ~~~~/"\ , ' ~/ __ ) (\Ofo.j'..-· '\ '\ /_.,. ,. 

-,\ . \~~~>//" .c,_ -~~;(\'~---

c~-::::::;, 

• 

Mixed Amphibole- _ _.-

garnet-epidote _/' 

//~/ 

• 

,./· 

/,/'/ 

• 

• 

• 

• Georges Bank 

• garnet 

• 

• 

• '• -,_ 

• 

• 

25 0 25 50 75 100 KILOMETERS 

DEPTH CONTOURS, IN METERS ~1f;/ ~""'~) ~&~,-

'------,,• '\ 

• 

• 

_! 

--\/ 

/ ... ~­ /: /,. ( 

) 

\.,,_ 

/ 

-~~6~/~/ "S- / Ri!!er f 

col.-./~-------

pe'l\o~~y 1-- / __ _ ,.---:""'"~ { 

/~" \ 

7 '--\ 

\) l __ ) 

.-(~~\5- (" ~~ \ '-· 111:.' 

- 'o ~~ lj.--... ~''::" 

~~ ___ J~. ?. "2~ < 

4 /\_~ 

/(' 

/ 

~-// • 

• • 

• 

• • 

.. ,:.::~:~,~.:: j ~~:--~'--" ~ 

• 

lOeb ._))&o 

_________ _,/( __ 

-,, 

··--... 

• 

~------------:-

~ <0 

• 

'~~'oo 

FIGURE 12.-Heavy-mineral provinces. 

~ 10 

"·-... .......... _ 

'11'-.?o 

'l?'l?o 

(ori, 

~ 

~ 

~ ~ 

~ ~rp 

8 

~ 

~ 

~ 

~ 

0 

~ 

~z 

z 

0 

~ 

[fJ 

() 

0 

1-3 

> 

~ 

~ 

~ 

c:... 

t>:l 

~ 

00 

t>:l 

t-<1 

0 

~ 
~ Q) 

TABLE 6.-Heavy-mineral a88ociation8 of the Gulf of Maine-GeorgeB Bank area and of the Long !Bland margin area 

[Individual heavy minerals are expressed as percentage of the nonopaque minerals. The opaque and 

standard 

altered 

deviation] grains are expressed as their percentage of the total heavy-mineral fraction. Upper value, mean; lower value; ~ 

Association; number of samples, in parentheses Amp hi- Epidote Augite Hyper- Titanite Tour- Zircon Garnet Stauro- Kyanite Anda- Silli- Opaque Altered ~ 1-1 

boles sthene maline lite lusite manite grains grains c 

c 

Gulf of Maine-Georges Bank area 0 

~ Penobscot amphibole (7).----------------------- 39.0 5.6 13.4 20.0 1.4 1.4 0. 7 6.4 2.7 1.0 6.4 1.3 20.8 43.0 !Z 

6.1 2.2 4.9 7.8 1.5 1.0 .5 4.1 5.2 1.0 2.6 1.4 8.3 13.5 t:rJ 

Kennebec amphibole (4) ____ ------------------- 55.0 3.5 9.5 7.2 1. 7 2.2 .2 11.0 4.2 .2 1.2 3.0 11.0 34.8 

~ 13.7 1. 9 2.9 5.1 1.3 1.9 .5 3.2 3.0 .5 1. 5 2.8 4.9 17.6 

Merrimack garnet (4>---------------------------- 20.2 3. 7 16.5 1.5 1.2 3. 7 .5 36.2 8.2 1.5 2.2 2.5 18.8 34.2 

4.5 2.1 9.5 1.0 1.0 3.3 .6 9.7 5.2 1.3 1. 7 2.9 6.4 13.5 

Gulf of Maine augite (32)------------------------ 28.5 6.5 29.2 4.9 1.5 2.8 2.0 15.7 3.2 1.9 2.1 .8 28.5 40. 3. 

~ 11.0 3.2 10.4 4.3 1.4 1. 9 3.0 9. 7 2. 7 1.8 2.2 1.3 11.0 10.5 

Gulf of Maine amphibole (14) ___ --------------- 36.9 9.6 9.1 3.6 1.9 5.9 1.5 17.1 5.4 .5 3.9 3.4 26.7 25.1 

10.4 5.1 4.6 2.2 1.6 2.8 3.1 8. 7 3.2 .6 3.1 1.8 11.7 12.6 

Gulf of Maine-Georges Bank complex (15) ----- __ 20.7 9. 7 13.8 3.2 2.3 5. 7 4.9 23.8 7.1 1.5 3. 7 1. 7 40.0 18.9 

8.1 2.7 4.5 1.9 1.9 2.9 4.0 3.9 3.6 1.5 2.6 1.6 9.8 13.3 ~ Georges Bank garnet (44) ___ ------------------- 10.7 4.1 5.1 3.3 2.9 5.2 5.2 40.7 14.4 1.1 4. 7 1.2 47.7 11.3 

Cape Cod garnet (20>--------------------------- 11.9 

6.7 

6.8 

2.7 3. 

2.8 

7 3.6 

1.3 

3.0 

2.3 16.1 

4.1 4.6 

4.1 27.8 

9.1 

16.5 

5.6 1.1 

.9 5.0 

3.5 

3.3 

1.2 

42.1 

12.3 

10.5 

7. 4 ~ 9.4 3.5 2.5 1.1 1.8 4.8 2.6 13.3 6.5 .7 3.4 2.3 12.9 8.4 '=' Scotian amphibole (5) _____________ ...,. ____________ 36.0 6.6 6.0 6.8 1.2 4.4 3.0 21.6 10.0 1.0 1.6 .2 30.6 19.2 rJl 4.9 4.7 2.5 2.3 .8 1. 9 1.2 5.2 3.5 .7 1.3 .4 5.9 12.9 t'4 

0 

'"d 

Long Island IIUU"Iin area t:rJ 

0 

Rhode Island amphibole (4>--------------------- 36.0 24.8 2.0 0.7 3.5 3.2 2.2 15.5 6.0 1.5 1. 7 2.2 33.5 20.8 I:J 

11.6 11.3 1.1 1.0 3.7 2.1 1. 7 5.3 3.9 .6 2.9 2.1 4.4 14.5 

~ Long Island Sound amphibole (5)--------------- 45.8 6.8 5.4 3.4 1.8 1.2 1.6 24.2 6.0 1.8 .8 0 22.6 15.4 

10.8 2.4 3.1 6.0 1.6 .4 1.3 11.1 2.0 1.1 .8 0 13.8 7. 9 Long Island garnet-staurolite (12) ••• _________ • _. 20.6 5.6 3.8 1. 7 1.8 4.3 1. 7 34.6 18.4 3.4 1. 7 1.1 32.3 5.2 

12.7 4.7 2.4 1.5 1.4 2.8 1.9 9.8 9.0 3.1 1.2 1.3 12.8 4.3 

Long Island garnet (7) ••• ----------------------- 14.6 7.0 6.9 2.3 1. 7 1.3 .6 57.3 5.3 1.1 .6 .9 32.7 6.6 

~ 5.6 4.3 7.2 2.1 1.0 .8 .5 11.9 2.7 1.5 .8 .9 10.4 4.8 

Mixed amphibole-garnet (41) -------------------- 26.0 9.0 6.9 3.8 2.3 6.0 4.4 24.4 8.0 1.8 3.2 3.0 41.0 9.8 

10.2 4.6 4.1 2.9 1. 7 3.3 3.5 7.6 3.1 1.4 2.6 2.1 9. 7 6.6 Mixed amphibole-garnet-epidote (15) ____________ 28.4 15.3 5.6 3.6 1.6 5.6 3.0 24.0 5.7 1. 7 2.3 2.8 41.3 12.5 t:rJ 

10.1 5.1 2.4 3.1 1.2 3.6 2.7 8.6 2.6 1. 7 1.6 1.9 12.2 4.6 '=' 

rJl 

~ 

~ rJl 
HEAVY MINERALS, CONTINENTAL MARGIN, NOVA SCOTIA TO NEW JERSEY G27 

TABLE 7.-Relation between heavy-mineral percentage and median 

grain Bize of the Band fraction of heavy-mineral aBBociationB in 

the Gulf of M aine-GeorgeB Bank area and in the Long I Bland 

margin area 

[Mdq,: median diameter, in phi units; phi is the negative logarithm to the base 2 or the grain size, expressed in millimeter] 

Association; number of 

samples, in parentheses 

Mean Correlamineral tion co- percent- efficient 

age 

Significant at 95 

percent 

level 

Gull of Maine-Georges Bank area 

Penobscot amphibole (7): Amphiboles ________________ 39.0 0.36 No __________ 

Hypersthene. _______ -- _____ 20.0 -.90 Yes _________ 

Augite _____ ----------------- 13.4 . 70 No __________ 

Ke~~~~!~~~~-~~~ ------ _ 55.0 .68 No __________ 

Garnet ____ ----------------- 11.0 -.83 No __________ 

Merrimack garnet (4): 

Garnet ____ --------------- __ 36.2 -.85 No __________ 

Gulf~£f~~~tigiii)(32): _______ 20.2 -.14 No __________ 

Augite _________ ------------- 29.2 .18 No __________ 

Amphiboles. __________ -- __ - 28.5 .25 No __________ 

Gamet. _____ --------------- 15.7 -.40 Yes _________ 

Gulf of Maine amphibole (14): Amphiboles ________________ 36.9 .05 No __________ 

Garnet ________ ------------- 17.1 -.54 Yes _________ 

Gulf of Maine-Georges Bank 

complex (15): Garnet ____ ---- ______ .------ 23.8 .42 No __________ 

Amphiboles ____ --------- ___ 20.7 -.11 No __________ 

Augite ____ ------------------ 13.8 -.36 No __________ 

Georges Bank garnet (44): Garnet ____ ------ __ ---.----- 40.7 -0.28 No __________ 

Staurolite ______ ------ __ ----- 14.4 -.38 Yes _________ 

Amphiboles. ____ - ___ ------- 10.7 .53 Yes _________ 

Cape Cod garnet (20): Garnet ____ -_-_._-_-_------- 27.8 -.22 No __________ 

Staurolite _____ -------------- 16.5 -.09 No __________ 

Tourmaline ______ -_-_-_-_-_- 16.1 -.12 No __________ 

Scotian amphibole (5): 

Amphiboles ____ ------------ 36.0 -.10 No __________ 

Garnet ______________ ------- 21.6 -.11 No __________ 

Long Island margin area 

Rhode Island amphibole (4): 

Amphiboles.-- __ ----------_ 36.0 -o.n No __________ 

Epidote _____ -------- ______ - 24.8 .72 No __________ 

Long Island Sound amphibole (5): Amphiboles. ____ ---- _______ 45.8 .87 Yes _________ Garnet _____________________ 24.2 -.90 Yes _________ 

Long Island garnet-staurolite (12): 

Garnet ____ ---_------ __ ----- 34.6 -.34 No _______ --- Amphiboles _______ • ________ 20.6 .54 No __________ 

Staurolite _________ • __ ------_ 18.4 -.36 NO---~------ Long Island garnet (7): 

Garnet. ___ ---_-----_-----_- 57.3 -.62 No __________ 

Amphiboles ________________ 14.6 .29 No __________ 

Mixed amphibole-garnet (41): Amphiboles. ______________ - 26.0 .21 No __________ 

Gamet ____ ---- ____ --------- 24.4 -.33 Yes.--------

Epidote ____ ---------------- 9.0 .42 Yes _________ 

Mixed amphibole-garnet- ~pidote (15): Amphiboles ________________ 28.4 .40 No __________ 

Garnet ____ ---- __ ------ __ --- 24.0 -.31 No __________ 

Epidote. __________ -------_- 15.3 -.15 No __________ 

Regression 

function, 

in percent 

32.7+1.9 Mdq, 40.7-6.1 Mdq, 

8.2+3.0Mdq, 

34.3+7.4 Mdq, 16.8-2.1 Mdq, 

49.8-5.4 Mdq, 21.3-4.1 Mdq, 

22.9+2.0 Mdq, 19.2+3.0 Mdq, 28.8-4.3 Mdq, 

35.1+5.7 Mdq, 33.6-5.0 Mdq, 

15.1+3.1 Mdq, 25.3-1.7 Mdq, 22.4-3.1 Mdq, 

44.4-2.2 Mdq, 17.6-1.9 Mdq, 5.5+3.1Mdq, 

34.3-3.2 Mdq, 17.7-0.6 Mdq, 17.4-0.6 Mdq, 

39.6-1.0 Mdq, 25.6-1.1 Mdq, 

75.7-11.5 Mdq, 

14.8+11.5 Mdq, 

13.9+10.0 Mdq, 58.1-10.7 Mdq, 

44.8-5.5 Mdq, 0.5H1.3Mdq, 

28.1-5.2 Mdq, 

79.0-14.8 Mdq, 9.7+3.3 Mdq, 

19.4+2.2 Mdq, 32.1-2.6 Mdq, 

3.2+1.9Mdq, 

7.5+5.4 Mdq, 37.9-3.6 Mdq, 19.5-1.1 Mdq, 

morphic source is indicated by the minerals (mainly 

garnets) in the Merrimack River. Wood fibers and coallike grains in the light fraction of the river sediments 

suggest that the river material is recent in origin (Ross, 

1967). Hence, these nearshore provinces may also be 

relatively young in age, in that sediment is being 

deposited at present or has been since the retreat of 

glaciers from the Gulf of Maine. 

The direction of dispersion of the river sediments is 

offshore; however, the number of samples examined is 

insufficient to define the dispersal pattern accurately. 

Surface currents in the Gulf of Maine (as measured by 

~ en ':S Q. 

LLI ~ lU ...J 

a.. "' 

:::!: 

<( 

en 

LLI 

a:: 

0 

:c 

en 

a:: 

<( 

LLI 1 z 

FIGURE 13.-Heavy-mineral composition of sediments collected 

from the Gulf of Maine region. Ep, epidote; Am, amphiboles; 

Ag, augite; Hy, hypersthene; G, garnet; St, staurolite; An, 

andalusite; Si, sillimanite; others, include, zircon, tourmaline, 

and titanite. The number in parentheses refers to the number 

of samples. From Ross (1967). 

drift bottles and other current-measuring devices) 

usually flow slowly (10 em per sec) from east to west. 

Off the Penobscot River (fig. 12) the dispersion of sediment is west to east, and here local sources of sediment, 

bottom topography, or local west-to-east transport by 

currents may be affecting sediment dispersion. 

The Gulf of Maine augite province differs from the 

nearshore provinces (table 6; fig. 13) in that augite, 

amphiboles, and garnet are the common heavy minerals; 

these minerals suggest a mixed source composed of volcanic, intrusive, and metamorphic rocks. Altered heavy 

minerals are very abundant in this province. The light 

fraction has large quantities of iron-stained quartz and 

feldspar (fig. 8B) and contains rock fragments, many of 

which are red sandstones. The sediments in this province are fine to coarse grained (fig. 7) and poorly sorted. 

Gravels are common off Nova Scotia and in parts of the 

central section of the Gulf. Much of the sediment of this 

area, except for the silt and clay in the basins, is thought 

to be glacial till and outwash (Hathaway and others, 

1965). These basin sediments may be a mixture of 

winnowed glacial sediment and fine-grained stream 

sediment. 
G28 ATLANTIC CONTINENTAL SHELF AND SLOPE OF THE UNITED STATES 

60 

40 

20 

0 

1- 40 

z 

LLJ 

(.) 

c:: 

~ 20 

z 

en 

~ 0 c:: 

LLJ 

z 

~ 

>-

~ 40 LLJ 

J: 

LLJ 

5 20 

0: 

0 

z 

~ 0 

60 

40 

20 

0 

Merrimack garnet 

• Cape Cod garnet 

LL 

Mixed amphibole-garnet 

Long Island garnetstaurolite 

(/) 

LL.J 

...JLLJ 

01-

mo 

-o :::c- c..C.. 

~LLJ 

<( 

LLJ 

z LLJLL.J 

1-J: _)-

(,!)(/) 

=>0::: 

<(LLJ c.. 

>-

:::c 

L 

Kennebec amphibole 

Gulf of Maine amphibole 

L 

Georges Bank garnet 

I 

L 

Long Island garnet 

(/) 

LL.J 

...JLLJ 

OlmO 

-o J:- c..C.. 

~LLJ 

<( 

LL.J 

z LL.JLL.J 1-:::c -1-

(,!)(/) 

::>0::: 

<(LL.J c.. 

>-

:::c 

l 

Penobscot amphibole 

Gulf of Maine augite 

Gulf of Maine-Georges 

Bank complex 

Mixed amphibole 

garnet-epidote 

(/) 

LLJ 

...JLLJ 

01-

mo 

-o J:- c..C.. 

~LL.J 

<( 

LL.J 

I-!:: 

LL.J...J 

zo 

c::C:: 

<(::> 

(.!)~ (/) 

LLJ 

z LLJLL.J 

1-J: _)-

(,!)(/) 

::>0::: 

<(LL.J a.. 

>-

:::c 

FIGURE 14.-Percentages of common nonopaque heavy minerals in some of the 

heavy-mineral provinces. 
HEAVY MINERALS, CONTINENTAL MARGIN, NOVA SCOTIA TO NEW JERSEY G29 

The mixed source indicated by the heavy minerals 

in the augite province is compatible with a glacial 

origin for these sediments. Considerable quantities of 

intrusive, volcanic, and metamorphic rocks occur in 

the areas that the glaciers presumably passed over; 

these rocks presumably were picked up and eventually 

deposited in the gulf. Glacial striations indicate that the 

ice moved across New England in a direction between 

south and east (Flint, 1957). The distribution of the 

mineral augite (fig. 3A), which is not influenced by grain 

size in this assemblage (table 7), suggests that sediments 

were picked up near the Bay of Fundy and transported 

southwest across part of the Gulf of Maine. There is 

also an indication of southeasterly transport toward 

Northeast Channel. The source for the augite may be 

the Fundy coast of Nova Scotia where a Triassic basalt 

and diabase sequence crops out and contains considerable quantities of augite (Nolan, 1963). Triassic red 

sandstones and siltstones are also common along the 

northern part of Nova Scotia, and these could be the 

source of the red sandstone fragments in the light 

fraction. Deeply eroded Triassic rocks occupy the floor 

of the Bay of Fundy and extend about 120 km into 

the Gulf of Maine (Tagg and Uchupi, 1966). These 

rocks could be the source for the abundant altered 

heavy minerals in this area. The presence of augite and 

the red sandstone fragments in the Gulf of Maine augite 

province apparently is due to glacial dispersion of 

Triassic material. Dispersion proceeded in a southerly 

direction to about lat 43° N. where either the quantity 

of augite became diluted or, less likely, the ice ceased 

its advance. 

The Gulf of Maine amphibole province, in the western 

and southern parts of the Gulf, has a:rri.phiboles and 

smaller quantities of garnet as the ,common heavy 

minerals (table 6). Altered minerals 'Me present in 

moderate amounts. The light fraction is mainly quartz 

and feldspar; stained grains of quartz and feldspar 

are less common here than in the Gulf of Maine augite 

province. Sediments are coarser grained and better 

sorted than in the augite province (fig. 7). Gravels 

are present in some of the samples. 

The sediments of the Gulf of Maine amphibole 

province are also apparently glacial in origin. Their 

mineral composition suggests a source from the intrusive and metamorphic rocks of southern New 

England or the Gulf of Maine. Dispersion seems to 

have been toward the southeast in a direction similar 

to striation directions and streamline features (such 

as drumlin orientations) of southern New England 

(National Research Council, Division of Earth Sciences, 

1959). 

A third glacial province is the Cape Cod garnet 

province; it extends off southeastern Massachusetts 

and includes areas of known end moraines and outwash 

sediments (fig. 10). Garnet, staurolite, and tourmaline 

typify the association, and altered minerals are relatively rare. The light fraction is dominantly quartz 

and feldspar. Sediments, mainly sand and gravel, 

are common off Cape Cod. The average grain size 

is coarser and the sorting better than in sediment~ 

of the other two glacial provinces. 

The heavy minerals suggest a mainly metamorphic 

source. However, the bedrock adjacent to this region 

is composed of relatively equal quantities of metamorphic and intrusive igneous rocks (fig. 9). The 

absence of intrusive igneous heavy minerals in this 

province is therefore surprising. This province includes very shallow areas, such as Nantucket Shoals, 

which are sites of extensive reworking by waves and 

tidal currents. Reworking may be indicated by the 

coarser grain size and better sorting of these sediments 

as compared with the other glacial marine deposits. 

It is possible that heavy minerals such as amphiboles, which are characteristic of intrusive source 

rocks and have moderately low resistance to abrasion, 

could have been removed from the assemblage by reworking or weathering. The mineral composition of 

this assemblage could also be influenced by pleistocene sediment eroded from Martha's Vineyard and 

Nantucket. 

The distribution of individual heavy minerals 

(tourmaline and staurolite, fig. 4) suggests that the 

sediments in the Cape Cod garnet province were 

transported offshore toward the south and east. End 

moraines and other glacial features also indicate 

southerly movements of glaciers in southeastern 

Massachusetts (National Research Council, Division 

of Earth Sciences, 1959). 

The sediments of the Cape Cod garnet province 

have been mixed with sediments from the Georges 

Bank garnet province. This is indicated by four samples 

from the Cape Cod garnet province that have mineral compositions so similar to the Georges Bank garnet province that the samples have been included 

in both provinces. These samples are from Nantucket 

Shoals, an area of strong tidal and current mixing. 

The Georges Bank garnet province extends from 

Nantucket Island across Georges Bank to the Scotian 

Shelf. Garnets and lesser amounts of staurolite and 

amphiboles are the common heavy minerals. Amphiboles, which occur in all the heavy-mineral provinces, 

are present in their lowest concentration in the Georges 

Bank garnet province (fig. 2B; table 6). Opaque minerals are very abundant, and altered minerals are 

rare. Sediments are well-sorted sand and gravelly sand. 

The origin of the sediments on Georges Bank is not 

known. If the glaciers covered or nearly reached the 
ATLANTIC CONTINENTAL SHELF AND SLOPE OF THE UNITED STATES 

top of Georges Bank, the sediments on the Bank 

could be glacial outwash. Alternatively, if the glaciers 

did not carry sediment to the Bank, one would expect 

the sediments on Georges Bank to be reworked Coastal 

Plain material. The available evidence indicates that 

a Coastal Plain origin for the sediment of Georges Bank 

is more probable. The uniformity of mineral composition over the extensive Georges Bank garnet province, 

as compared with the variability between the several 

heavy-mineral assemblages of glacial origin found in 

the Gulf of Maine, argues for one large and relatively 

homogenous source for the Georges Bank area. If 

glacial material similar to that deposited in the Gulf 

of Maine was carried to Georges Bank, more variations 

in mineral composition would be expected. It can be 

argued that glacial material similar to that in the 

Gulf of Maine was deposited on Georges Bank as outwash and that subsequent reworking and preferential 

sorting have modified the sediments to the assemblage 

presently observed. 

This idea can be tested by examining the relationship of the heavy minerals garnet and staurolite. The 

percentages of garnet and staurolite are grain-size dependent (table 4); both minerals are more abundant 

in coarser grained sediments. Comparison of the 

regression function for garnet and staurolite to median 

grain size of the sand fraction shows that the garnetstaurolite (G:S) ratio stays relatively constant with 

changes in grain size (table 8). Garnet and staurolite 

also have similar resistance to abrasion. Therefore, 

changes in the G: S ratio should reflect differences in 

source material and not grain size, reworking, or 

weathering. 

TABLE 8.-Relation of garnet and staurolite to the median diameter 

of the sand fraction of all samples 

Mediandiameter 

phi (Md<;) 

-1 

0 

1 

2 

3 

4 

Regression function 

Garnet Staurolite 

Percent =46.18 -7.28Md <; Percent=15.07-2.34Md <; 

53.5 

46.2 

38.9 

31.6 

24.3 

17.0 

17.4 

15.1 

12.7 

10.4 

8.1 

5. 7 

Garnetstaurolite 

ratio (G:S) 

3.17 

3.06 

3.06 

3.04 

3.00 

2.98 

The G :S ratio distribution (fig. 15) shows patterns 

similar to that of the heavy-mineral provinces (fig. 12). 

A band of low G: S values extends from Nova Scotia 

across Georges Bank and the inner part of the Long 

Island shelf. High G:S values occur mainly in the areas 

of glacially derived sediments from New England that 

were deposited in the Gulf of Maine and on parts of 

Georges Bank and the outer continental shelf and slope. 

The large differences in the G:S ratio between the Gulf 

of Maine and most of the Georges Bank area clearly 

indicate a different source for the two areas. The source 

for the Georges Bank sediments evidently is Coastal 

Plain material, either the sediments and rocks underlying the bank or Coastal Plain material removed from 

the Gulf by glaciers an~ deposited on Georges Bank.2 

On parts of Georges Bank the presence of sediments 

with high G: S ratios, similar to those of the glacial 

sediments in the Gulf of Maine, indicates that some of 

this glacial material may have reached the Great South 

Channel area of Georges Bank. R. M. Pratt (oral 

commun., 1966) observed gravel in this area, and its 

presence also indicates that glacial material was carried 

this far south. 

The low G:S ratios in Northeast Channel, an area 

of probable glaciation, indicate source material similar 

to that of Georges Bank; other aspects of mineral 

composition in the two areas are also similar. The 

presence of sediments with high G:S ratios on the 

continental slope off Georges Bank and Northeast 

Channel suggests that glacial material. like that in 

the inner parts of the Gulf of Maine has been transported to the deep sea. Torphy and Zeigler (1957) 

and Zeigler, Tuttle, Tasha, and Giese (1964) suggested 

that ice was present in Northeast and Great South 

Channels. During the glacial retreat, these channels 

could have served as drainage valleys and carried 

glacial material to the deeper parts of the continental 

slope and rise. If the sediments having high G: S 

ratios in this area of the deep sea represent glacial 

material a low rate of sedimentation is indicated 

because the material remains at the surface, and the 

Gulf of Maine was supposedly clear of ice 11,000 

years ago (Emery, Wigley, and Rubin, 1965). Additional 

samples from the continental rise area are needed to 

define the extent of glacial sediments. 

The G: S ratios for the Georges Bank garnet province 

are similar to the ratios in the sediments on the inner 

Long Island shelf. The Long Island shelf sediments 

probably are glacial outwash derived from Coastal 

Plain sediments; this is suggested by the incorporation 

of large quantities of Coastal Plain sediments into 

the Long Island moraines (Muller, 1965). 

Other arguments also indicate that the surface sedi .. 

ments of the Georges Bank garnet province were derived 

from the Coastal Plain. The heavy-mineral suite sug .. 

gests a metamorphic source; however, only in the Cape 

Cod garnet province are large quantities of metamorphic 

minerals found. It seems unreasonable to expect that 

2 The term "glacially derived" as used here applies to sediments transported by 

glaciers and deposited in an area where, because of grain size, mineral content, or the 

general bathymetry of the area, their glacial origin 1s obvious. It 1s difficult to apply 

the term "glacially derived'' to these sediments even if they were derived from Coastal 

Plain material removed from the Gulf of Maine by glaciers because the applicable 

criteria, if ever present, have been modified by reworking. The important point is 

that a ditferent source exists for the sediments of the Gulf of Maine than for Georges 

Bank. 
vo. 

1 !>.. 

'\<{; 

..;>6'. 

0 '\ 

b ~ 

25 0 25 50 75 100 KILOMETERS 

.YO>. ~ ro ~ro. 

G.....w..L _ _L__L__jl I 

DEPTH CONTOURS, IN METERS 

~ 10 

FIGURE 15.-Garnet-staurolite ratio contoUI'8. Note that the contour interval is exponential. 

Garnet-staurolite 

ratio 

- 0-2 

• 

Sample location 

~. 

~r~r. 

lOri-

~ 

~ 

~ 

~~ 

I 

~ 

~ 

~ 

~ 

[15 

0 

~ 

~ 

~ 

~ 

~ ~ 

~ 

>< 

ii 

..... 
G32 ATLANTIC CONTINENTAL SHELF AND SLOPE OF THE UNITED STATES 

the source of the sediment in the Cape Cod province 

also s~pplied sediment to cover Georges Bank and the 

Scotian Shelf. In addition, the sediments of the 

Georges Bank garnet province generally lack the significant amounts of tourmaline typical of the Cape Cod 

garnet province. A more probable explanation is reworking of the Coastal Plain sediments. This reworking 

has produced a "lag" deposit where the finer sized sediments have been removed while the coarser material, 

which contains relatively higher quantities of metamorphic minerals, remains. The original Coastal Plain 

material, therefore, did not have to be composed of only 

metamorphic minerals. Evidence presented in subsequent paragraphs suggests that the finer sized sediments 

removed from Georges Bank have been incorporated 

into the sediments on both the landward and seaward 

parts of the bank. 

An interesting aspect of the G: S ratios (fig. 15) 

is the band of sediments with moderately low G : S 

ratios that lies both landward and seaward of Georges 

Bank. These sediments, on the basis of their G:S 

ratios, are similar to those of Georges Bank. The heavymineral province on the Gulf of Maine side of the bank 

(Gulf of Maine-Georges Bank Complex) is composed 

mainly of equal quantities of garnet and amphiboles, 

with lesser quantities of augite. The median grain size 

is that of fine sand. Both the grain size and mineral 

composition of this province are intermediate between 

those of the Gulf of Maine augite province to the north 

and the Georges Bank garnet province to the south. It 

is proposed that the Gulf of Maine-Georges Bank 

Complex, referred to as the "complex" province, is the 

product of mixing fine-grained sediments from Georges 

Bank with the sediments of the Gulf of Maine. Sedimentation from Georges Bank into the Gulf of Maine is 

also suggested by continuous seismic profiles from the 

area. Uchupi (1966, p. 3025) found relatively thick 

sequences (greater than 80 m) of Recent and Pleistocene 

sediments immediately north of Georges Bank; the 

other parts of the gulf and Georges Bank have Recent 

and Pleistocene sediment thicknesses of about 20 m. 

The influence of the fine-grained sediments of 

Georges Bank on the heavy-mineral composition of 

the "complex" assemblage can be observed from 

figure 16 and table 9. The figure shows the best fit 3 

relationship of many of the heavy minerals in the 

Georges Bank garnet assemblage to the median 

grain size of the sand fraction. The average median 

grain size in the Georges Bank province is coarser 

than that in the "complex" province. The argument 

used is as follows: If one extrapolates the relation3 The best-fit line has been calculated using a .linear regression technique. In all 

cases the hypothesis of independence of mineral percentage to median grain size is 

rejected at the 0.10 level of significance. 

ship of a mineral percentage to grain size for the 

coarse-grained Georges Bank garnet province into 

the finer grain sizes the resulting mineral percentage should approach that of the finer-grained "complex" assemblage if the fine-grained material from 

Georges Bank constitutes part of the "complex" 

assemblage. For the more abundant minerals (table 

9), the compositions of these two assemblages become 

similar in the finer grain sizes, and the composition 

of a fine-grained Georges Bank garnet assemblage 

approaches the composition of the "complex" assemblage. 

TABLE 9.-Common heavy mineral.s in the Georges Bank garnet 

and "complex" provinces 

[Individual he.avy minerals are expressed as percentage of nonopaque fraction. Opaque 

and altered minerals are reported in percentage of total heavy-mineral fraction] 

Mineral 

Augite ______ . ___ ._ 

Epidote _____ ._._ - Amphiboles _____ _ 

Garnet ____ ·-· --· _ Staurolite __ , _____ _ 

~ft:~~--:~~:: ~: :: 

Georges Bank 

garnet 1 (median 

grain size 1.83 p hi 

=0.281mm) 

5.1 

4. 1 

10. 7 40.7 

14.4 

47. 7 11.3 

"complex" t 

(median grain size 

2.76 phi =0.147 

mm) 

13.8 

9. 7 20.7 

23.8 

7.1 

40. 0 

18.9 

Georges Bank 

garnet 2 (extrap(). 

lated to a median 

grain size of 2. 76 

phi =0.147 mm) 

6. 3 

4.8 

14.0 

38.5 

12.4 

44.1 

13. 1 

1 Data from table 6. 2 Data from fig. 16. 

Glaciers probably extended into the Gulf of Maine 

at least as far as the landward flank of Georges Bank. 

When the ice retreated, reworking removed the finer 

sized material from the sediments of Georges Bank and 

some sediment was carried landward and mixed with 

the glacial sediments of the Gulf of Maine to produce 

this "complex" assemblage. In the southwestern secz 

u) 

_J 

<Ia:::z 

ww 

zu 

-a::: 

:2:w 

>-CL 

> 

< 

w 

I 

50 -

- 40 -

30 -

20 -

-10 F=" 

0 

1.0 

I 

-=-

-

Opaques R=-0.31 

Garnet R=-0.28 

--===== 

Amphiboles R= 0.52 

Altered R=0.27 

Staurolite R=-0.38 

Augite R=0.35 

Epidote R=0.28 I 

2.0 3.0 

MEDIAN GRAIN SIZE OF 

SAND FRACTION (<!>) 

4.0 

FIGURE 16.- Best-fit lines of relation of percentages of common heavy minerals to median grain size of the sand fraction in the Georges Bank garnet province. Percentage 

for augite, epidote, staurolite, amphiboles, and garnet is 

percentage of the nonopaque fraction; percentage for opaques 

and altered minerals is percentage of total heavy-mineral 

fraction . R is the correlation coefficient. Data are for 40 samples from this province. 
HEAVY MINERALS, CONTINENTAL MARGIN, NOVA SCOTIA TO NEW JERSEY G33 

tion of this "complex" province (fig. 12), mixing of the 

Gulf of Maine amphibole and Cape Cod garnet assemblages with the Georges Bank garnet assemblage is 

probable. 

The Scotian amphibole province, on the continental 

shelf off Nova Scotia, is composed mainly of amphiboles and garnet. The median grain size is that of fine 

silt, and sorting is poor. This assemblage probably 

represents a fine-grained component of the Georges 

Bank garnet assemblage; the main difference between 

the two assemblages is the proportion of amphiboles to 

garnet. The median grain size of the Scotian assemblage is 82 microns and of the Georges Bank garnet 

assemblage, 287 microns. Amphiboles are more abundant in fine-grained sediments, and garnet is more 

abundant in coarser grained sediments in this region 

(table 4). Amphibole may have been winnowed from 

the sediments of Browns Bank. The similarity of the 

G: S ratios for these two assemblages suggests a similar 

source. The slight decrease in the G: S ratio off the 

southwestern tip of Nova Scotia may be due to the influence of a local supply of sediments. 

Although there is considerable evidence, such as 

poorly sorted sediments and irregular topography, 

that the Scotian Shelf was glaciated, no indication of 

this glaciation was discernible from the mineral 

composition of the small number of samples examined 

from this area. 

THE LONG ISLAND MARGIN AREA 

A mixed amphibole-garnet province extends seaward 

of Georges Bank and southwestward across parts of the 

continental shelf and slope off Long Island. This province is similar in heavy-mineral composition to the 

"complex" assemblage (fig. 14) on the landward side 

of Georges Bank. The major difference is the lesser 

quantity of augite on the continental slope. The augite 

in the "complex" assemblage apparently was derived 

by mixing with the Gulf of Maine augite assemblage. 

I propose that the mixed amphibole-garnet assemblage 

on the seaward side of Georges Bank is mainly derived 

from the fine-grained sediments reworked from the 

Georges Bank garnet province. The remaining sediments are the result of normal pelagic sedimentation 

and fine-grained materials winnowed from sediments 

on the Long Island shelf. Some detritus from the Gulf 

of Maine may have been carried across Georges Bank 

and dumped on the upper continental slope during 

lower stands of sea level. Arguments similar to those 

presented for the "complex" assemblage indicate the 

similarity of the fine-grained Georges Bank material to 

the mixed amphibole-garnet province (table 10). If 

the source of the mixed amphibole-garnet province is 

Georges Bank, sediment is dispersed in a southern or 

southwestern direction from the bank. 

TABLE 10.-Common heavy minerals in the Georges Bank garnet 

and mixed amphibole-garnet provinces 

[Individual heavy minerals are exp1 essed as percentuge of nonopaque fraction.Opaque 

and altered minerals are reported in percentage of total heavy-mineral fraction] 

Mineral 

Augite __________ _ 

Epidote_--------- Amphiboles _____ _ Gamet_ _________ _ 

Staurolite ________ _ Opaque __________ _ 

Altered _________ --

Georges Bank 

garnet 1 (median 

grain size 1.83 

phi=0.281 mm) 

5.1 

4.1 

10.7 

40.7 

14.4 

47.7 

11.3 

l Data from table 6. 2 Data from fig. 16. 

Mixed amphibolegarnet province 1 

(median grain size 

2.90 phi=0.134 mm) 

6.9 

9. 0 

26.0 

24.4 

8.0 

41.0 

9.8 

Georges Bank 

garnet 2 (extrapolated to a median 

grain size of 2.90 

phi=0.134 mm) 

6.4 

4.9 

14.4 

38.0 

12.1 

43.7 

13.4 

Seaward of the mixed amphibole-garnet province, 

along the lower continental slope and rise is a similar 

assemblage (mixed amphibole-garnet-epidote) that differs from the amphibole-garnet province only in having slightly higher contents of epidote and being of 

a finer grain size. Aside from the higher quantities 

of epidote, the source of this assemblage is probably 

similar to that of the slope assemblag.e: Georges Bank 

and the Long Island shelf. The source of the epidote 

is not obvious; however, some areas of epidote concentration are on the continental shelf south of New 

Jersey. This suggests transport of material from the 

south to the north and northeast. 

The G:S ratio increases (fig. 15) on the outer parts 

of the continental shelf, slope, and rise off New Jersey 

and Long Island. The pattern is suggestive of a southerly source of material with relatively higher quantities of garnet as compared to staurolite. The shelves 

of southern New Jersey, Delaware, Virginia, and the 

northern part of North Carolina are areas with high 

G:S values (D. A. Ross, unpub. data, 1969). Presumably sediments either at a lower stand of sea 

level or at present are being transported northeastward along the outer parts of the con tin en tal margin. 

This direction of transport is opposite to that proposed by Heezen, Hollister, and Ruddiman (1966), 

who suggested that much of the sediments of the 

continental rise were transported from the north by 

geostrophic contour currents. 

Two heavy-mineral provinces characterize the shelf 

off Long Island and northern New Jersey-the inner 

shelf has a garnet-staurolite assemblage, the outer shelf 

a garnet assemblage. The median grain size in both 

provinces is in the sand-size range; the garnet assemblage is coarser grained than the garnet-staurolite 

assemblage. The increase in garnet concentration 

seaward off Long Island may in part be due to an 
G34 ATLANTIC CONTINENTAL S'HELF AND SLOPE OF T'HE UNITED STATES 

increase in grain size in this area (fig. 7). These two 

provinces contain large quantities of Coastal Plain 

sediments, most of which probably were supplied to the 

area by the glaciers that covered much of Long Island. 

The moraines on Long Island contain large quantities of 

Coastal Plain material. The postglacial transgression 

has reworked these shelf sediments and removed much 

of the fine sediments, some of which probably have 

been incorporated into the finer grained sediments of 

the more seaward provinces. 

An amphibole-rich assemblage is present in Long 

Island Sound. Texture and mineral composition as 

determined from five samples in the Sound vary considerably. The distribution of amphiboles and garnet 

within this assemblage is controlled by grain size (table 

7). The three main rivers that empty into Long Island 

Sound (Connecticut, Housatonic, and Thames) drain 

areas of somewhat different lithology. Examination of 

additional samples from the Sound area should reveal 

the presence of additional provinces. 

An amphibole-epidote assemblage off Rhode Island is 

defined by four samples. It is at the juncture of several 

other provinces (fig. 12) and is similar to an amphibole 

assemblage McMaster (1962) observed in upper 

Narragansett Bay. 

CLASSIFICATION OF SEDIMENTS 

The surface sediments of the continental margin can 

be classified into two major groups-recent sediments 

and relict sediments (table 11). This classification is 

based on the depositional history of the sediments 

interpreted from light- and heavy-mineral distribution 

and other geologic characteristics. Further subdivisions 

are possible on the basis of sediment source and degree 

of reworking. Because this classification is made on the 

sand fraction of the sediments, it may have limited 

application to the silt and clay portions of the sediment. 

The distribution of the different sediment types is shown 

in figure 17. 

TABLE H.-Classification of the sediments on the continental 

margin between southern Nova Scotia and northern New Jersey 

I. Recent sediments: 

A. Sediments supplied by rivers. 

B. Deep-sea pelagic sediments (mixed with relict 

sediments). 

II. Relict sediments: 

A. Glacial sediments. 

1. Reworked. 

2. Relatively unreworked. 

B. Reworked Coastal Plain sediments (some glacial 

transport). 

C. Mixtures of glacial and nonglacial sediments. 

RECENT SEDIMENTS 

Recent sediments are represented by the three 

nearshore provinces off rivers that enter the Gulf of 

Maine-the Penobscot amphibole, Kennebec amphibole, and Merrimack garnet. The Rhode Island amphibole province off Narragansett Bay may be due 

to recent deposition from rivers. Much of the sediment 

carried by present-day rivers is trapped in their estuaries and does not reach the open basin. Other areas 

of recent sedimentation off rivers are undoubtedly 

present but were too small to be detected by the 

sampling pattern used in this study. 

River sediments in many localities overlie earlier 

deposited glacial sediments, and river and glacial 

sediments certainly have become mixed. The sediments found in Long Island Sound may be a mixture 

of these two types. 

Other recent sediments include beach and deep-sea 

pelagic deposits. Beach deposits have not been examined in this study. Deep-sea deposits are found on 

the continental slope and rise; these sediments are 

interpreted as a mixture of fine-grained relict sediments from Georges Bank and the Long Island shelf 

with normal pelagic sediments. 

RELICT SEDIMENTS 

Most of the sediments of the continental margin 

are relict sediments. Glacial sediments are found in 

the Gulf of Maine, off Cape Cod, and on the Long 

Island shelf; less extensive deposits are found on parts 

of Georges Bank and the deeper continental slope and 

rise. The glacial sediments usually are poorly sorted 

and variable in texture; gravels are common. Glacial 

sediments are of two .types: sediments that have been 

reworked and have had their unstable mineral components removed and sediments that have undergone 

little, if any, reworking. 

Five provinces, as defined by their heavy-mineral 

suites, are of glacial origin. Three of these, the Cape 

Cod garnet, Long Island garnet, and Long Island 

garnet-staurolite provinces have been extensively 

reworked by waves and tides. This reworking has 

removed much of the finer grained sediments and 

redeposited them in more seaward areas of the continental margin. Reworking has also resulted in 

the removal of unstable minerals; the heavy-mineral 

composition of these three provinces is dominated 

by stable heavy minerals resistant to abrasion such 

as garnet and staurolite. These glacial sediments 

are generally coarser grained and better sorted than 

the sediments of the other glacial provinces. 

The two heavy-mineral provinces in the Gulf of 

Maine, an augite and an amphibole province, have 

mineral compositions similar to those anticipated from 
VOo 

1D-" 

..YOlo 

1c) 

• • 

EXPLANATION 

Areas of more than one pattern 

indicate mixed sources of 

sediment 

', 

~ ~ 

~ . 

Rivwoediments / 

~ 

Reworked glacial 

sediments 

ffii]] 

Relatively unreworked 

glacial sediments • 

~-4000----..J\ 

~ "'" Reworked Coastal "" 

Plain sediments "" 

• Sample location 

ro~ 

' 

\))cfo 

,'\ ~./ ~~~i\Y 

/ l'.pY '\ ~/ ~ '. .ll '\ ~, ... ; ' ~'<· ''\! ::::-..~, -.... \ .... .;:: ..,.... - ... II 

25 0 25 50 75 100 KILOMETERS U.....W..L _ _L_j_ __ J_ ____ J ~9:> / ~/-- DEPTH CONTOURS, IN METERS 

Ri~_J 

~'be~- 4 

~~/ / 

/ / 

/ 

/' 

~·<;.}; {/ 

:\.<\.~~-~~) ....... ~/~~ .._, 

7~ 

;}j: ... ~ u\~ 

\ {_(.~(~ ~ 

q l 

)f __ _i.~~ 

":> 

', // ':<' ~,.-~-d..-'"' ~ cv•/:~x >---., 

// / ._...v,.__,X, 

,'/ ~ .,.-1./~ ( 

/ 1- ( J _ _) ,!T--r-200-(" 

''-'-'---'----..,__,Y.J-

····-,,, ·-...,_____ '-/'\ 

''-, ~- . I / 

. / .;>.;,::~ ~-----------4ooo-~---~/ // ~ ' - }4# '" . ----, 

'""' -L--., '·-,)<.<' "" '?. ___ ,__ // -,,,_ 

' ', "' --- ',,, // -------'---- /- ..... _ _,.\ ..... 

b (() ,o. .; b 

FIGURE 17 .-Classification of bottom sediments on the continental margin. 

y~o 

,,... 

ro'i· 

~ 

~ 

~ ~ 

~ 

I 

~ 

~ 

--~ 

~ 

~ 

f!5 

0 

~ 

~ 

~ 

~ 

~ ~ 

~ to<l 

~ 01 
G36 ATLANTIC CONTINENTAL .SHELF AND SLOPE OF THE UNITED STATES 

the outwash of glaciers that had crossed the potential 

source areas of these provinces. Some sediment, however, may be derived from rocks within the Gulf of 

Maine. Reworking of these sediments seems to have 

been minimal (discussed in more detail in the following 

section) and moderately unstable mineral species are 

common. 

The sediments of Georges Bank are reworked, relict 

Coastal Plain sediments. The source of these sediments 

is either the Gulf of Maine, where glaciers removed the 

material and transported it to the bank, or the underlying material of Georges Bank. The extent of the 

glaciers onto Georges Bank is unknown; however, 

there is evidence of glaciation on the bank. 

The sediments of Georges Bank have been extensively reworked; the heavy-mineral suite is composed 

of minerals resistant to abrasion. Sediments are coarse 

sand with little fine-grained material. I postulate that 

the finer sediments of Georges Bank, which contained 

relatively large quantities of minerals such as amphiboles and augite, have been removed by currents and 

waves and deposited both landward and seaward of 

the bank. In the landward direction, this has resulted 

in an assemblage that is a mixture of glacial and nonglacial Georges Bank material (the "complex" province). Seaward and to the south of Georges Bank are 

two fine-grained provinces, the mixed amphibolegarnet, and the mixed amphibole-garnet-epidote. These 

sediments are derived from the finer sediments of 

Georges Bank and the glacial material on Long Island 

shelf. 

DISPERSAL AND MODIFICATION OF SEDIMENTS 

The direction of dispersion of sediments is mainly 

offshore (fig. 18). An exception is Georges Bank, where 

some sediment is carried landward into the Gulf of 

Maine. Georges Bank isolated the Gulf of Maine from 

the deep sea except by way of Great South and Northeast Channels. These channels allowed some glacial 

material to reach the deep sea; photographs and samples 

from the channels show that they are floored with a 

coarse gravelly till-like sediment. However, most of 

the glacial material deposited in the Gulf of Maine 

probably still remains there. Off Long Island, some 

dispersion is suggested along the shelf and slope. The 

use of only surface sediments restricts the discussion 

of sediment dispersion to present or near-present conditions. During times of lowered sea level, dispersal 

patterns were probably more restricted. 

Rising sea level subjected the Long Island shelf and 

Georges Bank to the reworking effects of waves and 

tidal currents. Longshore currents undoubtedly transported material along the existing shoreline. Finer material was winnowed from the sediments and carried 

out to sea. Georges Bank, during most ot the recent 

rise of sea level, acted as a barrier or breakwater to 

the Gulf of Maine, protecting the area from much of 

the reworking effects or waves and permitting the 

deposition of fine-grained sediments. 

That the Gulf of Maine is a low-energy environment is shown by the large quantity of relatively 

unstable and altered minerals in the gulf and the poor 

sorting of the sediment. Chemically unstable and 

weathered minerals should be anticipated in glacial 

sediments because extensive weathering would be 

retarded and mechanical abrasion and transport 

would prevail in the glaciers. This effect is also noted 

from areas having high relief or strong diastrophism 

(for example, the Gulf of California, van Andel, 1964). 

In the Gulf of Maine, unstable material is apparently 

preserved because of the relative deepness of the 

present gulf and the limited reworking of sediment 

during the Holocene rise in sea level. 

Reworking, either by selectively sorting or by mechanically breaking the easily altered grains, has 

modified the glacial sediments off Cape Cod and Long 

Island. These glacial sediments have been sufficiently 

reworked to produce mineral suites considered stable 

according to abrasion criteria. 

Sediments from the Jordan and Wilkinson-Murray 

Basins and the adjacent ridge areas were examined 

to seek any difference that could be attributed to 

sediment reworking or differences in source material 

supplied to the ridge and basin areas (Ross, 1970). 

In the Jordan Basin, the mineral composition and 

texture of the basin and ridge sediments were not 

statistically different. 

In the Wilkinson-Murray Basin, the ridge and 

basin sediments were also similar, although the removal of one basin sample of an anomalous grain size 

would establish a significant difference in grain size 

between the two areas. The basin sediments did 

differ in having a finer grain size and a higher occurrence of altered minerals when compared to values 

from the Gulf of Maine amphibole province, which 

includes the basin area. Causes of the above observations may be that some fine material has been 

winnowed from the shallower water sediments and 

deposited in the deeper basins. The larger quantities 

of altered minerals may in part be due to the finer 

grain size; altered minerals tend to be more common 

in the finer grain sizes (table 4). 

The submarine canyons off Georges Bank and the 

Long Island shelf do not seem to transport material 

to the deep sea at present. Except for Hudson Canyon, these canyons generally start on the continental 

slope. The Hudson Canyon intersects the shelf and 

may have intercepted sediments that are moving or 
'll"Oo 

1().0 

"1. 

a6'o 

1c) 

', ---~/ .. ;;,~// ( ·''v-. 25 0 25 50 75 100 KILOMETERS "I ~~/ 'B-~1)~~\..,/\ lr-/ 

,./" '\, »'// ·,\ .,~:::>"(f .. :"' 

~-/ ,, __ \ DEP~~O-NT~-R~-~~-M-E;E R s 

<.t-( -~7 ,/-<i;.';;' o~I'J"'/ ~ / '--, .r,ll'''~~~ ~i,\le,y 

ll/! c.,~/ ?' ~-9//'V~j 

~"'-/..~/.' <:J~./t"'~- .l 

• 

• 

• 

/ •. / 

/ / 

/"• 

/ ... , // // '·, / 

\., _/ 

~ ', // 1

1 ',, / II r1 ',, /. I// )<, 

~ / / ~---. . / 

/ / "'i.__ \. ___ "--·-~----- / 

', /' \., / 

'·,., /' 

g; 0 

...... \. / 

'\. // 

x 

/ "· // \."' ,/ \ 

a&., 

' J:,<§/ ' 'y/ 

\!' 

,,, l 

(~""-= 

;,_j 

_________ /t_ __ /-'\..._ 

• • 

~ co 

/ ~ ( 't'/ ~"' .-oeS---/ / i.:;-'1 ~{ ''!-.~"'..,. 

( c,cy/Portland I "fo_'-~7 . -' <. ~l?./R1ver 

• 

• 

• 

• 

~\ . .......... , 

·,,,. \ . '''··,,,, \/ 

)',,\ 

,/ {'-, / I 

)'~?;:::~ -;j 

River , 

-:osr,o~j~--- ---· 

pe.'11-o /r /----~-

-1--

/.( / 

• 

/ 

,,./' 

// 

/ 

/ / //.1' 

/ / 

/ 

/ 

/ -------4ooo-__ / 

.....____ _______ ::/---~-- --•, 

'S?o., ~ ~ 

/ 

:/. v/ ~ 

t,'~""'.. ( ( \_ \ "1 

(") !_ --<·~o"-s. --

L~ G I 

'S?._:>., 

"' \ 

).f r\o __ !. ..... 

"':' 

FIGURE 18.-Dispersal pattern of sediments. Question marks indicate areas where insufficient evidence is available to assign a positive direction. Probably all 

patterns, except those off rivers, are relict from the Pleistocene. Heavy-mineral province boundaries are from figure 12. 

'S?'S?o 

~rC 

~ 

~ 

t?;l 

~ ~ 

E: 

Jll 

g 

z 

~ t?;l 

~ 

Q 

~ 

~!2! 

~ U2 

0 

0 

~ 

> 

~ 

~ 

~ 

~ 

= 

~ to<! 

~ '-1 
G38 ATLANTIC CONTINENTAL SHELF AND SLOPE OF THE UNITED STATES 

have moved recently toward the northeast across the 

shelf. 

The preceding discussion has shown that the heavymineral composition of the sediments is mainly a 

function of source, although in some instances after 

deposition the composition has been modified. These 

modifications are the result of selective sorting, weathering of unstable minerals, and possibly some diagenetic processes. Areas of shallow water that are 

exposed to strong wave and tidal forces are the sites 

of the most pronounced modification. 

Some evidence concerning the modification of the 

light fraction was observed. Clean, mainly quartz, 

sand is found in areas where the modification of the 

heavy minerals has been most pronounced: Georges 

Bank, off Cape Cod, and on the Long Island shelf. 

Stained grains with a higher proportion of feldspar 

are more common in the Gulf of Maine. The low 

feldspar-quartz ratios of Georges Bank as compared 

with the relatively high ratios in the Gulf of Maine 

may indicate the difference in reworking between these 

two areas; however, this difference in ratios may 

only reflect initial differences in mineral composition 

between the areas. 

Sediment texture is controlled mainly by Pleistocene 

relict processes and by later modification by marine 

currents. The coarse well-sorted sands of Georges 

Bank and the Long Island shelf are evidence of the 

effect of the marine environment on texture. Coarse 

till-like sediments in the Gulf of Maine apparently 

have been little affected in their present environment. 

Two distinct sediment types dominate the area: 

(1) mature sands with abrasionally stable heavymineral suites, which occur on the Georges Bank, 

Cape Cod area, and off Long Island, and (2) relatively 

immature mixtures of sand, silt, and clay having a 

heavy-mineral suite of low stability. This second type 

occurs mainly in the Gulf of Maine. A third sediment 

type on the slope and rise is a silt-clay mixture with 

small amounts of sand that has a mineral suite of 

intermediate stability. 

CONCLUSIONS 

The study of the heavy-mineral fraction of the sand 

fraction, and to a lesser degree the light-mineral fraction, 

has indicated 15 heavy-mineral provinces within the 

area of study. Mineral composition is controlled mainly 

by source, although mineral assemblages have been 

modified by selective sorting, weathering, or diagenetic 

processes. Modification is most pronounced in the 

high-energy areas of Georges Bank, off Cape Cod, and 

on the Long Island shelf. Over the entire area of 

study the percentages of several heavy minerals have 

a significant correlation with grain size. However, 

within the heavy-mineral provinces, differences in 

grain size generally cannot account for differences 

between the provinces. 

The sediments of the continental margin can be 

divided into recent and relict sediments. Recent sediment is represented by three heavy-mineral provinces 

off rivers that enter the Gulf of Maine. Two other 

provinces, one off Narragansett Bay and the other in 

Long Island Sound, may also have recent sediments. 

The remaining provinces are composed of relict 

sediment. Glacial sediment occurs in the Gulf of Maine, 

off Cape Cod, and on the Long Island shelf. Reworking 

by waves and tides has modified the mineral assemblage 

and texture of the sediments of the Cape Cod and Long 

Island areas. Georges Bank has protected the sediments 

of the Gulf of Maine from extensive marine reworking. 

Glaciers probably did not completely cover Georges 

Bank during the last glaciation. The sediments on 

Georges Bank are coarse-grained reworked Coastal 

Plain sediments. The fine-grained sediments of the 

bank have been winnowed out by waves and currents 

and deposited both landward and seaward of the bank. 

The winnowed sediments are presently mixed with 

sediments of glacial origin. 

Sediments have been deposited mainly offshore. 

Exceptions are the landward dispersion of sediment 

from Georges Bank and possibly some dispersion 

along the coast of Long Island. Some glacial material 

has been deposited on the continental slope and rise 

off Northe,ast Channel and Georges Bank. 

REFERENCES CITED 

Bailey, J. W., 1851, Microscopical examination of soundings, 

made off the coast of the United States by the Coast Survey: 

Smithsonian Contr. Knowledge; v. 2, art. 2, 15 p. 

Burbank, W. S., 1929, The petrology of the sediment of the Gulf 

of Maine and Bay of Fundy: U.S. Geo. Survey open-file 

report, 74 p. 

Curray, Joseph R., 1965, Late Quaternary history, continental 

shelves of the United States in Wright, H. E., Jr., and Frey, 

D. G., eds., The Quaternary of the United States: Princeton, 

N.J., Princeton Univ. Press, p. 723-735. 

Donner, Joakim, 1964, Pleistocene geology of eastern Long 

Island, New York: Am. Jour. Sci., v. 262, no. 3, p. 355-376. 

Drake, C. L., Ewing, Maurice, and Sutton, G. H., 1959, Continental margins and geosynclines-The east coast of North 

America north of Cape Hatteras in Volume 3 of Ahrens, 

L. H., and others, eds., Physics and chemistry of the earth: 

New York, Pergamon Press, p. 110-198. 

Drake, C. L., Worzel, J. L., and Beckmann, W. C., 1954, Gulf of 

Maine, Part 9 of Geophysical investigations in the emerged 

and submerged Atlantic Coastal Plain: Geol. Soc. America 

Bull., v. 65, no. 10, p. 957-970. 

Emery, K. 0., Merrill, A. S., and Trumbull, J. V. A., 1965, 

Geology and biology of the sea floor as deduced from simultaneous photographs and samples: Limnology and Oceanography, v. 10, no. 1, p. 1-21. 
HEAVY MINERALS, CONTINENTAL MARGIN, NOVA SCOTIA TO NEW JERSEY G39 

Kaye, C. A., and Barghoorn, E. S., 1964, Late Quaternary 

sea-level change and crustal rise at Boston, Massachusetts, 

with notes on the autocompaction of peat: Geol. Soc. 

America Bull., v. 75, no. 2, p. 63-80. 

McMaster, R. L., 1962, Petrography and genesis of Recent 

sediments in Narragansett Bay and Rhode Island Sound, 

Rhode Island: Jour. Sed. Petrology, v. 32, no. 3, p. 484-501. 

McMaster, R. L., and Garrison, L. E., 1966, Mineralogy and 

origin of southern New England shelf sediments: Jour. Sed. 

Petrology, v. 36, no. 4, p. 1131-1142. 

Muller, E. H., 1965, Quaternary geology of New York, in 

Wright, H. E., Jr., and Frey, D. G., eds., The Quaternary 

of the United States: Princeton, N.J., Princeton Univ. Press, 

p. 99-112. 

Murray, H. W., 1947, Topography of the Gulf of Maine, field 

season of 1940: Geol. Soc. America Bull., v. 58, no. 2, 

p.153-196. 

National Research Council, Division of Earth Sciences, 1959, 

Glacial map of the United States east of the Rocky Mountains: New York, Geol. Soc. America, 2 sheets, scale 

1:1,750,000 (linch=about 28 miles). 

Neal, W. J., 1964, Heavy mineral petrology of Wisconsin and 

post-glacial deep-sea sands and silts, western North Atlantic: Columbia, Mo., Missouri Univ. M.S. thesis, 164 p. 

Nolan, F. J., 1963, Heavy mineral analysis of the beach sands 

of Nova Scotia: Halifax, Nova Scotia, Dalhousie Univ. 

M.S. thesis. 

Emery, K. 0., and Uchupi, Elazar, 1965, Structure of Georges 

Bank: Marine Geology, v. 3, no. 5, p. 349-358. 

Emery, K. 0., Wigley, R. L., and Rubin, Meyer, 1965, A 

submerged peat deposit off the Atlantic coast of the United 

States: Limnology and Oceanography (Alfred C. Redfield 75th Anniversary Volume), v. 10, supp., p. R92-R102. 

Flint, R. F., 1957, Glacial and Pleistocene geology: New York, 

John Wiley & Sons, Inc., 553 p. 

Gibson, T. G., 1965, Eocene and Miocene rocks off the northeastern 

coast of the United States: Deep-Sea Reseach, v. 12, 

no. 6, p. 975-981. 

Hathaway, J. C., Schlee, J. S., Trumbull, J. V. A., and Hulsemann, Jobst, 1965, Sediments of the Gulf of Maine [abs.]: 

Am. Assoc. Petroleum Geologists Bull., v. 49, no. 3, p. 

343-344. 

Heezen, B. C., Hollister, C. D., and Ruddiman, W. F., 1966, 

Shaping of the continental rise by deep geostrophic contour currents: Science, v. 152, p. 502-508. 

Johnson, D. W., 1925, The New England-Acadian shore line: 

New York, John Wiley & Sons, Inc., 608 p. 

Kaye, C. A., 1964, Outline of Pleistocene geology of Martha's 

Vineyard, Massachusetts in Geological Survey reseach 

1964: U.S. Geol. Survey Prof. Paper 501-C, p. C134-C139. 

North American Geologic Map Committee, 1965, Geologic 

map of North America: U.S. Geol. Survey, 2 sheets, scale 

1:5,000,000 (1 inch= about 80 miles). 

Pourtales, L. F. de, 1870, Der Boden des Golfstromes und der 

Atlantischen Kuste N ord-Amerika's: Petermann's Mitt. 

aus Justus Perthes' Geo. Ans. v. 16, p. 393-398. 

--- 1872, The Gulf Stream-Characteristics of the Atlantic 

sea-bottom off the coast of the United States: Report of 

the Superintendent, U.S. Coast Survey for 1869, App. 

11, p. 22Q-225. 

Ross, D. A., 1967, Heavy mineral assemblages in the nearshore 

surface sediments of the Gulf of Maine in Geological 

Survey research 1967: U.S. Geol. Survey Prof. Paper 

575-C, p. C77-C80. 

--- 1970, Source and dispersion of surface sediments in the 

Gulf of Maine-Georges Bank area: Jour. Sed. Petrology 

(in press). 

Rvachev, V. D., 1965, Topographic relief and bottom sediments 

of the Georges and Banquereau Banks [translated from 

1964 Russian pub. by E. R. Hope]: Canada Defence Research Board Directorate Sci. Inf. Services Rept. T 436 

R, 7p. 

Schafer, J. P., and Hartshorn, J. H., 1965, The Quaternary of 

New England, in Wright, H. E., Jr., and Frey, D. G., 

eds., The Quaternary of the United States: Princeton, N.J., 

Princeton Univ. Press, p. 113-128. 

Shepard, F. P., 1939, Continental shelf sediments, in Trask, 

P. D., ed., Recent marine sediments, a symposium: Tulsa, 

Okla., Am. Assoc. Petroleum Geologists, p. 219-229. 

Shepard, F. P., and Cohee, G. V., 1936, Continental shelf sediments of the mid-Atlantic States: Geol. Soc. America Bull., 

v.47,no.2,p.441-458. 

Shepard, F. P., Trefethen, J. M., and Cohee, G. V., 1934, Origin 

of Georges Bank: Geol. Soc. America Bull., v. 45, no. 2, 

p. 281-302. 

Smith, W., and Mcintyre, A. D., 1954, A spring-loaded bottom 

sampler: Marine Biol. Assoc. Jour., v. 33, p. 257-264. 

Stetson, H. C., 1949, The sediments and stratigraphy of the east 

coast continental margin, Georges Bank to Norfolk Canyon: 

Massachusetts Inst. Technology and Woods Hole Oceanog. 

Inst., Papers in Physical Oceanography and Meteorology, 

v. 11, no. 2, p. 1-60. 

Stewart, H. B., Jr., and Jordan, G. F., 1964, Underwater sand 

ridges on Georges Shoal in Miller, R. L., ed., Papers in 

marine geology-Shepard Commemorative Volume: New 

York, Macmillan Co., p. 102-114. 

Tagg, A. R., and Uchupi, Elazar, 1966, Distribution and geologic 

structure of Triassic rocks in the Bay of Fundy and the 

northeastern part of the Gulf of Maine in Geological Survey 

research 1966: U.S. Geol. Survey Prof. Paper 55Q-B, p. 

B95-B98. 

Tate, M. W., and Clelland, R. C., 1957, Nonparametric and 

shortcut statistics: Danville, Ill., Interstate Printers and 

Publishers, Inc., 171 p. 

Thornbury, W. D., 1965, Regional geomorphology of the United 

States: New York, John Wiley & Sons, Inc., 609 p. 

Torphy, S. R., and Zeigler, J. M., 1957, Submarine topography 

of Eastern Channel, Gulf of Maine: Jour. Geology, v. 65, 

no. 4, p. 433-441. 

Uchupi, Elazar, 1963, Sediments on the continental margin off 

Eastern United States in Short papers in the geologic and 

hydrologic sciences: U.S. Geol. Survey Prof. Paper 475-C, 

p. C132-C137. 

---1965a, Map showing relation of land and submarine 

topography, Nova Scotia to Florida: U.S. Geol. Survey 

Misc. Geol. Inv. Map I-451, 3 sheets, scale 1:1,000,000. 

---1965b, Basins of the Gulf of Maine in Geological Survey 

research 1965: U.S. Geol. Survey Prof. Paper 525-D, 

p. D175-D177. 

---1965c, Topography and structure of the shelf and slope: 

Woods Hole Oceano g. Inst. Ref. 65-13, p. 84-87. 

---1966, Structural framework of the Gulf of Maine: Jour. 

Geophys. Research, v. 71, no. 12, p. 3013-3028. 

Uchupi, Elazar, and Emery, K. 0., 1967, Structure of continental margin off Atlantic Coast of United States: Am. 

Assoc. Petroleum Geologists Bull., v. 51, no. 2, p. 223-234. 

van Andel, Tj. H., 1964, Recent marine sediments of Gulf of 

California, in van Andel, Tj. H., and Shor, G. G., Jr., eds., 
G40 ATLANTIC CONTINENTAL SHELF AND SLOPE OF THE UNITED STATES 

Marine geology of the Gulf of California: Am. Assoc. 

Petroleum Geologists Mem. 3, p. 216-310. 

Wigley, R. L., 1961, Bottom sediments of Georges Bank: Jour. 

Sed. Petrology, v. 31, no. 2, p. 165-188. 

0 

Zeigler, J. M., Tuttle, S.D., Tasha, H. J., and Giese, G. S., 1964, 

Pleistocene geology of outer Cape Cod, Massachusetts: 

Geol. Soc. America Bull., v. 75, no. 8, p. 705-714.