ILLUSTRATIONS

PLATES

PLATEFOLLOWING PAGE
1.Physiographic diagram: Atlantic Ocean, Sheet 1 (In separate tube)
2.Preliminary chart of Hudson Submarine Canyon[20]
3.Representative PDR records from continental rise of northeastern United States[32]
4.PDR records from continental slope and Blake Plateau[32]
5.PDR records from outer ridge east of the Blake Plateau and from the Blake-Bahama Abyssal Plain[32]
6.PDR record of outer ridge showing sub-bottom horizon[32]
7.Tracings of PDR records across continental slope and part of the Blake Plateau[36]
8.PDR records European continental rise and Biscay Abyssal Plain[38]
9.Representative PDR records of continental margin and abyssal floor southwest of Canary Islands[38]
10.PDR record of abyssal hills, southeast of Bermuda Rise[38]
11.Ocean bottom photographs of the continental margin and ocean basin floor[38]
12.PDR record of Biscay Abyssal Plain[52]
13.PDR records of Madeira Abyssal Plain and the Madeira Rise[52]
14.PDR records of Mid-Ocean Canyon No. 2 and canyons at Vema Gap[58]
15.Ocean-bottom photographs of seamounts[58]
16.Representative PDR records from Bermuda Rise[78]
17.PDR record, Bermuda Scarp Zone[78]
18.PDR record, Upper Step Mid-Atlantic Ridge[78]
19.Ocean-bottom photographs; Mid-Atlantic Ridge[78]
20.Physiographic provinces, Atlantic Ocean[122]
21.Control chart[122]
22.Six trans-Atlantic topographic profiles[122]
23.Index chart showing locations of profiles of Plates 24, 25, 26 and Figure 45[122]
24.Thirty-four profiles of the continental margin: western North Atlantic[122]
25.Twenty-three profiles of the continental margin of Europe and Africa[122]
26.Crustal structure and continental-margin provinces[122]
27.Five topographic profiles, western North Atlantic[122]
28.Distribution of deep-sea sands in relation to physiographic provinces[122]
29.Earthquake epicenters, North Atlantic[122]
30.Location of PDR records and bottom photographs reproduced as illustrations.[122]

FIGURES

FIGUREPAGE
1.Method of preparation of physiographic diagram[4]
2.Precision depth recorder (PDR) sounding lines obtained by research vessels[6]
3.Good, but nonprecision sounding lines obtained by research vessels[7]
4.Major basins of the North Atlantic, after Wüst (1940)[12]
5.Sound-velocity corrections for echo soundings[13]
6.Conversion diagram for degrees, per cent grade, feet per statute mile, and gradient[14]
7.Gradients from 1:5 to 1:8000 shown at 40:1 vertical exaggeration[15]
8.Outline of submarine topography[15]
9.Major morphologic divisions: North Atlantic Ocean[16]
10.Three categories of continental-margin provinces[17]
11.Two east-west profiles of Southeast Newfoundland Ridge[22]
12.Laurentian Channel[23]
13.Eastern Channel, Gulf of Maine[23]
14.Submarine canyons off the Scotian Shelf[24]
15.Continental-margin provinces: Type profile off northeastern United States[26]
16.Tracings of PDR records of continental and insular slopes[28]
17.Cross sections of Hudson Submarine Canyon[32]
18.Tracing of PDR record of Blake Escarpment[34]
19.Continental-margin provinces: Type profiles off northwest Africa[40]
20.Georges Bank canyons[44]
21.Two projected profiles of Georges Bank canyons[45]
22.Geologic section at Cape Hatteras, Virginia[46]
23.Correlation of structural benches off northeast United States[48]
24.Geologic section: Western Europe based on refraction measurements[49]
25.Index chart, location of abyssal hill profiles illustrated in Figures 26 and 27[62]
26.Eleven profiles, Abyssal Hills Province, western Atlantic[62]
27.Eight profiles, Abyssal Hills Province, eastern Atlantic[63]
28.Tracing of PDR record, abyssal hills, southeast of Bermuda Rise[64]
29.Northwest Atlantic Mid-Ocean Canyon[67]
30.Eight east-west profiles showing Northwest Atlantic Mid-Ocean Canyon[68]
31.Forty-eight cross sections of Northwest Atlantic Mid-Ocean Canyon[69]
32.Long profile of Northwest Atlantic Mid-Ocean Canyon[70]
33.Tracing of PDR record across Theta Gap[73]
34.Natural scale profile, Kelvin Seamounts[77]
35.Crustal sections in various physiographic provinces, determined by seismic-refraction measurements[81]
36.Index to natural-scale Mid-Atlantic Ridge profiles reproduced in Figures 37-41[84]
37.Natural-scale Mid-Atlantic Ridge profile 1A[85]
38.Natural-scale Mid-Atlantic Ridge profile 1B[86]
39.Natural-scale Mid-Atlantic Ridge profile 1C[87]
40.Natural-scale Mid-Atlantic Ridge profile 2A[88]
41.Natural-scale Mid-Atlantic Ridge profile 2B[89]
42.Type profile, provinces of the Mid-Atlantic Ridge[90]
43.Tracing of PDR record, Rift Valley, Rift Mountains, High Fractured Plateau, and Upper Step[91]
44.Tracing of PDR record, Western Rift Mountains[92]
45.Twenty-six rift valley profiles, Mid-Atlantic Ridge[93]
46.Five representative profiles, crest and western flank of Mid-Atlantic Ridge[94]
47.Axial profile of the Mid-Atlantic Ridge[96]
48.Profile of total magnetic intensity and topography, Mid-Atlantic Ridge[101]
49.Physiographic provinces and trans-Atlantic structure[102]

TABLES

TABLEPAGE
1.Characteristics of continental rise, northeastern United States[27]
2.Characteristics of continental rise, northwest Africa[41]
3.Depths of prominent continental-shelf terraces[42]