PHYSIC‘S OFTHE EARTH

AYDPLAKETARY IYTERIORS

Physics of the Earth and Planetary Interiors 96 (1996) 223-297

The Flinn-Engdahl Regionalisation Scheme: the 1995 revision

J.B. Young a. * , B.W. Presgrave ‘, H. Aichele ‘, D.A. Wiens d, E.A. Flinn et’ a A WE Bluckne.\t. Brinyron. Reudin~ KG7 4R.S. UK

b r htrtioncrl Eurthyucrkr I@rmutron Centre. USGS Suroey. P.O. Box 25046. Stop 967. Denoer Federul Center.

Drnurr. CO 80225. USA

’ Srrsmo/o~t.vchrs Zrntralohsrruutorium. Krunkrnhau.t.strcrJ.te 1-3. D-91054 Eriurpw. Grrmuq

d Dqxutment oJ’Eorth ctnd Plunetury Sciences. Washington Unioersuy. P.O. Box 1169. Saint Louis. MO 63130. 1JSA ’ NASA, Wo.\hrngton, DC, USA

Received 27 November 1995: accepted 9 January I996

Abstract

The Flinn-Engdahl Regionalisation Scheme, also known as the F-E Code, has been used by seismologists for many years to identify and specify regions of the Earth. The Working Group on Regionalisation of the International Association of Seismology and Physics of the Earth’s Interior (IASPEI) Commission on Practice has the task of defining a new standard for the regionalisation of the Earth. In the meantime, it was agreed that a revision of the F-E Code would be appropriate. This paper presents the 1995 revision and supersedes the F-E Code standard published in 1974.

1. Introduction

The Flinn-Engdahl Regionalisation Scheme is the standard list of names and boundary definitions used by seismologists to specify and identify regions of the Earth. The Scheme was first proposed by Flinn and Engdahl (I 965) who described the criteria for defining and naming regions. The standard known as the F-E Code was published by Flinn et al. (1974)

’ Corresponding author. Dedication: Ted Flinn’s influence was not only Earth-wide but also reached the outer-most planets of our Solar System. This paper tlluminates one small part of Ted’s work and is dedicated to his memory.

’ Deceased.

with a minor revision of region names published by Young and Pooley (1986).

The original regionalisation of the Earth was done by Gutenberg and Richter (1954). They studied more than 4000 large earthquakes recorded over a period of nearly 50 years and plotted the epicentres on a world map. On this map they drew 5 1 regions, which were numbered l-51, and allocated descriptive names; the regions of high seismicity, being, in general, smaller in area than those of low seismicity. One consequence of this is that oceanic regions having sparse seismicity cover a larger area than most continental regions.

The regionalisation proposed by Flinn and Eng- dahl (1965) is a subdivision of 50 of the Gutenberg and Richter regions (regions 5 1 and 30 being merged) so forming a mosaic within the larger region. Ini- tially, there was a total of 729 subdivisions. Some adjustment of the large region boundaries also had to

003 I-9201 /96/S15.00 Copyright 0 1996 Elsrvter Science B.V. All rights reserved. P/I SOO~1-9~Ol(96~O~l~l-X

224 J.B. Youn,q et ul./PItyi~~.~ oft/w Eurth und Planetury Interiors 96 (1996) 223-297

be made. Flinn and Engdahl called the large regions “seismic regions” and the subdivisions forming the mosaic “geographical regions”.

When the F-E Code was published by Flinn et al. (1974) most seismological agencies such as the In- ternational Seismological Centre (ISC) and the US Coast and Geodetic Survey (USCGS) had adopted the regionalisation and were using it routinely in their publications. The F-E Code contained 728 geographical regions (numbered l-729, region 172 no longer in use> with names, and 50 seismic regions (numbered l-50) also with names. With the increas- ing accuracy of hypocentres it became apparent that in some areas of the Earth the F-E Code was inadequate for regionalising epicentres. For example, Chandra (19751, Aichele and Peterschmitt (1977), and Young and Pooley (1986) published criticisms of the F-E Code. So in 1985, the Commission on Practice (COP> of the International Association of Seismology and Physics of the Earth’s Interior (IASPEI) established a Working Group on Regional- isation at the IASPEI Assembly in Tokyo. The COP asked Dr E.A. Flinn to be the Group’s Chairman with the task of defining the new standard for the regionalisation of the Earth. In 2 years Dr Flinn appointed members of the Group and the first meet- ings were held at the International Union for Geodesy and Geophysics (IUGG) Assembly in Vancouver in 1987. At its meetings in 1987 and 1988 the Working Group decided that the new standard would be a seismo-geographical regionalisation based on poly- gons defining ‘local’ regions of seismic, tectonic, geographic, and other features. It was also agreed at that time that the new standard would include some minor corrections to the F-E Code.

This work was started but by the time of the meeting of the Working Group at the IASPEI As- sembly in Istanbul in 1989 Ted Flinn had died. The first author (Young) was appointed as Chairman by the COP in succession to Dr Flinn. Three short papers by Young (19881, Young and Wiens (19901, and Young and Presgrave (1995) have been pub- lished describing the changes made to the F-E Code. The purpose of this paper is to bring together all this work and present a revised F-E Code. This paper supersedes the special issue of the Bulletin of the Seismological Society of America (BSSA) describ- ing the F-E Code published by Flinn et al. (19741

and is the current standard definition of the F-E Code.

2. The revised F-E Code

The region boundaries in the F-E Code follow integer values of latitude and longitude. The smallest region is one degree square, for example, Region 271, Buru, Indonesia, and the largest is Region 611, North Pacific Ocean, covering thousands of square degrees. There are 754 geographical regions (num- bered l-757, regions 172, 299, and 550 no longer in use) which form a mosaic within the seismic regions (numbered l-50). The seismic regions have re- mained unchanged since Flinn and Engdahl (1965) proposed the regionalisation and for completeness are illustrated in Fig. 1. (Note that this map has been adapted from Flinn et al., 1974; Young and Pooley, 1986 and the ISC Regional Catalogue of Earth- quakes, e.g. International Seismological Centre, 1995.) The seismic regions are called the first level regions. or Level 1; being a coarse regionalisation of the Earth. For this revision, 28 new geographical regions have been added; with two, Region 299, Southeast Asia, and Region 550, Northwest Affica, being completely replaced by new regions. All other new geographical regions reduce the size of existing regions. Geographical regions are called second level regions, or Level 2; being a finer regionalisation of the Earth. (The third level regions, or Level 3, are for ‘local’ regionalisation but the description of this system is beyond the scope of this paper.) Note that the boundary definitions of the regions in the F-E Code remain fixed.

All the region names in the F-E Code have been reviewed, see Young et al. (1993), and the list of both seismic and geographical region names pre- sented in Appendix A is the best current description. However, use of the names is not mandatory and the list is only our recommendation. For example, both the ISC and the NEIC (National Earthquake Informa- tion Centre, successor to the USCGS) tend to use names that are shorter than those in Appendix A.

3. The 28 new geographical regions

The 28 new geographical regions have been in- cluded after consultation with users of the F-E

225

1 I I

226 J.B. Young er ul. /Physics oj’the Earth und Plonerory Interrors 96 (19961223-297

tl I

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464 468 9o”w

463 465'-

1 467

.

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104

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Fig. 2. Regions centred on 20”N 94”W illustrating new regions 730, 731 and 757.

J.B. Youq et (11. /Physic\ ofthe Eurth cod Plunctury Interiors 96 (19961 223-297 227

729 t

3o"w 20% 10% I ~'l,',,1,,,~l/,,_~,/,,l,,,,i/

Fig. 3. Regions centred on 65”s IS’W illustrating new region 732.

,

228 J.B. Young rf d./Phy.w.~ ofrhr Earth urul Plmetury Interiors 96 (1996) 223-297

12O'E 1.' * 658 . . .

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Fig. 4. Regions centred on 20% IOYE illustratmg new regions 733-737.

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Fig. 5. Regions centred on 65”N 29”W illustrating new region 738.

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FIX. 6. Regions centred on 20”N 4’W illustrating new regions 739, 743-755.

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,- 60°E

Fig. 7. Repmns centred on 2O”N 65”E illustrating new region 710.

232 J.B. Young et uI./Physics of’rhr Eurth und Plonrtury 1nrrr1or.s 96 (1996) 223-297

I I 1 1 / ! I 1 L

Fig. 8. Regons centred on 203 70”E illusuatmg new region 741.

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Fig. 9. Regions centred on 65’S I26”E illustrating new region 742.

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Fig. IO. Regions centred on 203 99”W illustratmg new rqyons 756, part 757.

J.B. Youn~q et ul. / Ptry.sic\ of r/w Earth trnd Plummry Inrrrror.\ 96 1/9Y6) 223-297 235

Code. The accepted regions are necessarily a com- promise between conflicting interests and is probably the minimum amount of change required to produce an acceptable new standard. The new regions have been defined in three separate published papers (Young, 1988; Young and Wiens, 1990; Young and Presgrave, 1995) on the assumption that the number- ing of the regions would be consecutive. However, at the IUGG Assembly in Vienna in 1991 the Working Group decided that the regions should be put into seismic region number order so the numbering of the regions has been changed from that in the first two papers. (Note the region boundary definitions are unchanged so are not being repeated here.) The region numbers allocated are 730-757 following on from the l-729 in the 1974 F-E Code standard. The regions are shown by shading in Figs. 2-10 with the seismicity included to demonstrate the reasons for defining the region. The 28 new geographical re- gions are described below and shown on one or more of Figs. 2-10.

Region 730 Northern East Paci$c Rise Region 757 Galapagos Triple Junction region

These two regions enclose the area of seismicity stretching from the Galapagos Triple Junction west of the Galapagos Islands, northwards towards the southwest coast of Mexico. The reason for the two regions is that the two existing geographical regions which are split, are in different seismic regions. Region 730 is in seismic region 5 and divides Re- gion 63. Off coast of Mexico, into two parts. Region 757 is in seismic region 44 and divides Region 693, Eastcentral Pacific Ocean, with the smaller part in the east, lying north of Region 696, Galapagos islands region and Region 695, West of Galapagos Islands, and the larger part to the west. The geo- graphical regions 63 and 693 are now classed as aseismic. Both regions 730 and 757 are illustrated in Fig. 2 and the southern part of 757 is also shown in Fig. 10.

Region 73 1 North qf Hondurus

The region is based on a proposal for a new geographical region for the Cayman Islands (M. Isaacs, personal communication. 1986) but is a com-

promise as the proposed region involved changing existing boundaries. The region encloses the seismic- ity in the northwest comer of Region 94. Caribbean Sea, between Region 85, Cuba region, and Region 72, Honduras, and west of Region 86, Jamaica region. The reduced region 94 is now classed as aseismic. Note that adjacent Region 93, Belize, now appears to be wrongly placed but both regions 731 and 93 remain as part of seismic region 7. The area is illustrated in Fig. 2.

Region 732 East of South Sandwich Islands

This region encloses the area of seismicity from the South Sandwich Islands Trench eastwards to- wards the triple junction of the Atlantic-Antarctic Ridge and Region 410, Southern Mid-Atlantic Ridge. Region 156, Southwestern Atluntic Ocean, is split in two with the larger portion stretching west to Region 155, Antarctic Peninsula, and the smaller part to the northwest of Region 153, South Sandwich Islands region; the revised region being classed as aseismic. Flinn and Engdahl (1965) thought the seismicity of the Mid-Atlantic Ridge and South Sandwich Islands followed Region 152, South Georgia Rise; this geo- graphical region is in fact aseismic. Region 732 is illustrated in Fig. 3 and shown as part of seismic region 10.

Region 733 Thailund Region 734 Laos Region 735 Kampuchea Region 736 Vietnam Region 737 Gulf of Tongking

Regions 733-736 are from one of two groups of political subdivisions of geographical regions; region 737 being an oceanic region. These five regions subdivide Region 299, Southeast Asia, which is no longer in use. Because region 299 is in seismic region 25, regions 733-737 remain the same and constitute about a third of the area of the seismic region. This is illustrated in Fig. 4.

Region 738 Reykjanes Ridge

Flinn and Engdahl (1965) ‘forgot’ about the area of seismicity joining the Mid-Atlantic Ridge to Ice-

land. Region 738 links Region 403, Northern Mid- Atlantic Ridge, to Region 637, Iceland region, which includes the northern end of the Reykjanes Ridge. Region 402, North Atlantic Ocean, then has only sparse intraplate seismicity and is classed correctly as aseismic in seismic region 32. Fig. 5 shows the necessity for region 738.

Region 739 Azores-Cape St. Vincent Ridge

The seismicity in this region between the Western Mediterranean area and Region 404, Azores Islands and north of Region 393, Madeira Islands, Portu- gal, region is relatively low with the earthquakes only being located with any accuracy since Flinn and Engdahl’s proposal (Flinn and Engdahl, 1965). This region was the easiest to define requiring only one east-west line to create it from Region 402, North Atlantic Ocean. As with region 738. region 402 is slightly reduced in size with region 739 remaining in seismic region 32. The region is shown in the north- west comer in Fig. 6.

Region 740 O\rsen Fracture Zone region

Even though Region 417, Arabian Sea, is a rela- tively small oceanic region the tectonic features are well known. Region 740 encloses practically all the seismicity in region 417 to the northeast of Region 416. Socotra region, leaving the remainder of the region aseismic. The seismic region is unchanged as 33 and the whole area is illustrated in Fig. 7.

Region 741 Indian Ocean Triple Junction

The region encloses the seismicity associated with the Indian Ocean Triple Junction and separates it from Region 425, South Indian Ocean. Region 429. Mid-Indian Ridge, is reasonably well defined except for part being in Region 427, Mauritius-Reunion region, which was also considered for subdivision but it was felt that it is not large enough to justify defining a new geographical region. Region 428, Southbrlest Indian Ridge, is extended by this region to join up with region 429. The seismic region stays as 33. The Southern Indian Ocean seismicity is well illustrated in Fig. 8.

Region 742 Western Indian-Antarctic Ridge

The seismicity of the ridges south of Australia is sparse with the geographical regions coarsely de- fined. Region 437, Sourh of Australia, is split into two roughly equal parts by this region to enclose the seismicity along the Indian Rise as far as the Antarc- tic Ridge. Neighbouring Region 435, Southeast Kn- dian Ridge, and Region 701, West of Macquarie Island, were considered for new regions but are not so large as to warrant subdivision. Therefore only region 437 has been changed becoming classed as aseismic and the seismic region number stays as 33. Fig. 9 shows the extent of the region but has little detail as to global position.

Region 743 Western Sahara Region 744 Mauritania Region 745 Mali Region 746 Senegal-Gambiu region Region 747 Guinea region Region 748 Sierra Leone Region 749 Liberia region Region 750 Cote d’lvoire Region 751 Burkina Faso Region 752 Ghana Region 753 Benin-Togo region Region 754 Niger Region 755 Nigeria

Regions 743-755 are the second group of wholly political subdivision of geographical regions. These 13 regions subdivide Region 550, Northwest Africa, leaving this region no longer in use. As region 550 is in seismic region 37 all the new regions lie in this seismic region. Fig. 6 shows the regions.

Region 756 Southeast of Easter Island

This region is another example of how Flinn and Engdahl (1965) failed to accurately define a known tectonic feature. The feature is the West Chile Rise partly defined by Region 686, West Chile Rise, but some of the seismicity occurs to the south in Region 692, Southern Pacific Ocean. The region is in two parts and removes the earthquakes associated with the tectonic activity from region 692 which remains classed as aseismic. The seismic region remains as 43. Fig. 10 illustrates the reason for this region.

J.B. Youn,~ et d./Phy.ws ofrhr Earth und Plunrtury Inrrriors 96 (1996) 223-297 237

I’ I I I j ‘1’ I I 1 i I I ’ I

_180°W 1 7o"w 16O'W 150°w 9&v<

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675 675

6761,

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16 ~

17

t c 611 _ 180°W 170°w

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Fig. I I. Regions centred on 65”N 163”W.

238

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1 I’ ” 90°N

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+

MAP 12

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239 J.B. Your~g rr u/./ Pt~y.w:~ o/ r/w Eorrh und Plunrwy Inrenm 96 (19961 223-297

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Fig. 14. Regions centred on 65”N 75”W.

J.B. Youn,q rr ~1. / Phy.\w.s of the Eurth untl Planrrury Intrrrors 96 (1996) 223-297 241

7-v--.- I 1 I I ’ 1 ’ 9O”Yj

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Fig. 15. Regions centred on 65”N 45”W.

242 J.H. Young rr d.,‘Phjw.\ ofrhe Eorrh unrl Planrrury 1nrrnor.s 96 (1996) 223-297

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Fig. 16. Regions centred on 65”N 15”W.

1 3o”w

J.B. Ymnfi ct ul./Phy.uc~s oj’the Earth uml Plmrtury /rut+-ton 96 (1996) 223-297 243

t- 639 [_70”N

641 MAP 17

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FIN. 17. Regions centred on 6YN 15”E

244

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Fig. 18. Regions centred on 6S”N 45”E.

J.B. Young et ul./Phy.\m oj’thr Earth crnd Plunetury Interiors 96 (1996) 223-297 245

1 MAP 19 r 644

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Fig. 19. Regions centred on 65”N 75”E.

246 J.B. Youn,q et d./Phy.w.\ of the Eurth urul Plonrtory Intrriors 96 (1996) 223-297

I -’ 1 1 90°Nl , I 90°E 1OO’E 633 1lO’E 120”E ] r i -- - 7

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Fig. 20. Regions centred on 6S’N 105”E

J.B. Young rt ul./Physic~.\ ofthe Eurth wtd Plunetury Intrrror.\ 96 (1996) 223-297 241

I” I I”’ / 1 ; ( I / ( ’ ) I I , 9o”sj

1 120°E 130'E 140'E 150% i

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654 80’N’

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655 IA F---h - 668i

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Fig. 2 I. Regions centred on 65”N I WE.

248 J.B. Your~,q e: ul./Physic.s ofthe Eurrh and Plunetury Interiors 96 (1996) 223-297

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Fig. 22. Repons centred on 65W 163%.

j 18'O'W

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FIN. 23. Regions centred on 2O”N 163’W.

249

250 J.B. Young el aI./ Physics of the Eurth und Planetary Interiors 96 (1996) 223-297

/ I 1 I I I

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14o”w 13o”w

; 611 611 3o

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38

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Fig. 24. Regions centred on ZO”N 135”W.

J.B. Young et d./Phyks ofthe Earth und Planefury Interiors 96 (1996) 223-297 251

t .-- , ;- , -- I ,. /

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Fig. 25. Regions centred on 2O”N 105”W.

I I

252 J.B. Youn,g rr ul./ Physics ofrhe Earth md Plunetury 1ntrrior.s 96 (19Y61 223-297

t-

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Fig. 26. Regions centred on 20”N 75”W.

J.B. Youtq et ul. / Phytict oj thr Eurtlr orul Plonrtcrry Interior.\ 96 f 1996) 223-297 253

t

t

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Fig. 27. Regions centred on 20”s 45”W.

40°N

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254 J.B. Young et d./Physic.s oft/w Earth und Planrtury lntrrkm 96 (1996) 223-297

I MAP 28 20’N

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Fig. 28. Regions centred on 20”N I SOW.

J.B. Young rr ul./Phy.w.s ofshe Eorrh ud Planetury lnrerior.s 96 (19961223-297 255

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Fig. 29. Regions centred on 20”N 15”E.

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Fig. 30. Regions centred on 20”N 45”E.

J.B. Young et ul. /Physics oj thr Eurttt und Plmwtury Intmors 96 (i996) 223-297 257

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Fig. 32. Regions centred on 20”N IOYE.

J.B. Youtrg et ul. /Physics oj’thr Earth clnd Plunctury Interiors 96 (19961223-297 259

r

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Fig. 33. Regions centred on 20”N 135”E.

260 J.B. Young et crl./Phy.sic.\ oj’rhe Eurrh md Plorwtury Inrrriors 96 (19961223-297

611

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Fig. 34. Regions centred on 20°K 163”E.

261 J.B. Youq et ul./Physics of the Earth und Plonrrury Irttrriors 96 119961 223-297

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262 J.B. Youn,g et ul./ Physics ofthe Earth ud Plunctary Intrriors 96 (1996) 223-297

611 611

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Fig. 36. Regions centred on 203 I35”W.

J.B. Young er al. / Physrcs of the Earth md Planetary Inreriors 96 f 1996) 223-297

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264 J.R. Youtt,e et ul./Phy.sic.\ ofrhc Earth und Plunrtq Interiors 96 (1996) 223-297

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J.B. Young et al. /Physics ofthe Eurrh uml Planemy Itrtrriors 96 (19961223-297 271

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274 J.B. Young er ol./Physics of the Earth und Planetary Inreriors 96 (1996) 223-297

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278 J.B. Young rt ol./Physics of‘ the Earth crd Plunetury Interiors 96 (1996) 223-297

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J.B. Yourr,q rt ul./Phy.,ics of’rhe Eortll und Plonetury Interior.\ 96 (1996) 223-297 285

Region 757 Galapagos Triple Junction Region

See description of region 730 and Fig. 2.

4. Pictorial presentation of the F-E Code

The whole of the F-E Code including the 28 new regions is presented in a series of 48 maps. These maps are upgrades of those presented by Young et al. (1988) but without the seismicity and with an improved database of coastlines. Every effort has been made to identify clearly each geographical re- gion with its number, taking into account its posi- tion, size, and coastlines. Each map covers an area of 45” of latitude and 30” of longitude, with a few degrees of overlap except at the Poles and the Inter- national Dateline. The 48 maps are split into four sets of 12 with each set being in a band of latitude from 18O”W to 180”E at 65”N, 20”N, 20%. and 65”s. One further map is included showing the position of the 48 maps on the same world projection as Fig. 1.

Note that there are many exceptions to the above as readability is the overriding criterion.

Each map has a large banner indicating its num- ber usually in the centre near the top, but on a number of maps the banner is placed in a suitable clear space. They also all have an outside grid marked in degrees with each 10 degrees marked N (north) or S (south), E (east) or W (west). Hence each region is displayed as a rectilinear box unless it is large when it will spread over several maps. The North and South Polar regions spread right across 24 maps!

All maps include coastlines to show the area of the Earth covered. Every attempt has been made to print the region number away from coastlines but in some areas like the Philippine Islands the numbers have had to be over-printed.

The first band of mdpS is numbered 1 l-22 (Figs. 1 l-22) the second 23-34 (Figs. 23-34), the third 35-46 (Figs. 35-46), and the fourth 47-58 (Figs. 47-58). A cylindrical projection is employed as in Flinn and Engdahl (1965) so that the first and fourth band of maps are more distorted with the North and South Poles stretching across the top and bottom of the maps respectively. The map of maps is numbered 59 (Fig. 59). Hence, all regions are illustrated as rectilinear; the geographical regions being enclosed by normal straight lines and the seismic regions by thickened lines. Coastlines are included and are from the World Data Bank II (WDBII) database but only the first level of detail has been used and any errors in the database have not been corrected. Every geo- graphical region has its number printed at least once within it, with its position chosen largely to give legibility. Four sizes of printing for the numbers are used; small, medium, large, and extra large with the size usually being chosen on the following criteria:

On each map the numbers have usually been positioned so that the they do not result in ‘over- crowdin g’, yet provide the required information. The symbols used by Flinn and Engdahl (1965) and Young and Pooley (1986) to identify small regions have thus been avoided.

5. Using the F-E Code

small medium

regions usually only one degree wide; border and coastal regions, regions at the edges of maps. ‘busy’ regions:

Flinn and Engdahl (1965) say of their regionalisa- tion that it is “intended to provide uniformity of geographical description. speed up the regular publi- cation of epicentre information, and aid in seismicity studies.” When the F-E Code was published 9 years later by Flinn et al. (1974) little had changed from the original proposal. Now this new standard, whilst appearing to make major changes to the F-E Code in fact changes less than 1% of the geographical region numbers in, say, a world earthquake database. For example, about I in 200 earthquakes reported to the ISC has a region number change. Obviously, there will be no change in seismic region numbers. The region name changes have improved the geo- graphical description of a substantial number of regions though some names have had to remain political. The main effect of the new regions should be observed in seismicity studies with seismic areas being better defined.

large normal indicator for most regions: This paper. we hope. maintains the ethos of the extra large ocean regions and the two polar regions. original F-E Code but obviously with modem com-

J.B. Young et uI./Physic.s ofthe Earth and Plunetury Interior.\ 96 (1996) 223-297

J.B. Young rr ul./Physic.s oflhc Eurrh urul Planerory lnreriors 96 (1996) 223-297 287

puters the way the F-E Code is used in seismologi- cal processing has greatly changed. However, it is the authors’ intention to provide users with the method of looking up a region number and name in the way in which they are accustomed. Maps like those published by Flinn and Engdahl (1965) are provided but we hope with far greater clarity. In keeping with modem publications a CD-ROM is provided with original data, look-up tables similar to those published by Flinn et al. (19741, and computer programs written in both Fortran and C. However, the maps of Figs. 11-58 can easily be used to quickly look up a region number using Fig. 59 to identify the individual map.

The work on the revised F-E Code was largely completed for the IUGG Assembly in Vienna in 1991. The Working Group on Regionalisation was requested to consult seismological agencies and other users to try out the revised code and report any problems. This task was completed for the IUGG Assembly in Boulder in 1995 when final approval of the revised standard of the F-E Code was given by IASPEI; hence the 1995 revision. It was hoped that the NEIC would be the first seismological agency to formally adopt this revision of the F-E Code to be followed by other agencies that use its publications. However, circumstances have delayed its implemen- tation. At the time of going to press, the ISC, which has a 2-year lag in its publications, is also not able to commit to adopting the revised code immediately, that is for the next Bulletin year (19951, but only to do so in the near future. When the ISC does adopt this revision of the F-E Code it is likely to continue to use it for some time.

Acknowledgements

We acknowledge the support of many colleagues in the international community of IASPEI. In partic- ular, we thank Dr E.R. Engdahl as the co-author of the F-E Code firstly as Chairman of the Commis- sion on Practice and then as Secretary-General of IASPEI. The first author thanks his colleagues at Blacknest, in particular, Professor A. Douglas, with- out whose support there would probably have not been a revision of the F-E Code. The input from other members of the Working Group on Regionali-

sation is also acknowledged. The contribution made by seismological agencies, in particular the ISC and the NEIC, and by companies, in particular Bradford University Software Services (BUSS) for SIMPLE- PLOT and Elsevier Science for publishing this re- port, is also recognised.

Appendix A. Seismic Region Names with Geo- graphical Region Identification

1 ALASKA - ALEUTIAN ISLANDS ARC

I Central Alaska, United States 2 Southern Alaska, United States 3 Bering Sea 4 Komandorsky Islands, Russia, region 5 Near Islands, Aleutian Islands, United

States 6 Rat Islands, Aleutian Islands, United

States 7 Andreanof Islands, Aleutian Islands,

United States 8 Pribilof Islands, Alaska, United States 9 Fox Islands, Aleutian Islands, United

States 10 Unimak Island. Alaska, United States,

region 11 Bristol Bay, Alaska, United States 12 Alaska Peninsula, United States 13 Kodiak Island, Alaska, United States,

region 14 Kenai Peninsula, Alaska, United States I5 Gulf of Alaska 16 South of Aleutian Islands 17 South of Alaska

2 EASTERN ALASKA TO VANCOUVER ISLAND

18 Southern Yukon Territory, Canada 19 Southeastern Alaska, United States 20 Off coast of southeastern Alaska, United

States 21 West of Vancouver Island 22 Queen Charlotte Islands, Canada, region 23 British Columbia, Canada 24 Alberta, Canada

288

2.5 Vancouver Island, Canada. region 26 Off coast of Washington. United States 27 Near coast of Washington, United States 28 Washington-Oregon border region 29 Washington, United States

3 CALIFORNIA - NEVADA AREA 30 Off coast of Oregon, United States 31 Near coast of Oregon. United States 32 Oregon. United States 33 Western Idaho. United States 34 Off coast of northern California. United

States 35 Near coast of northern California, United

States 36 Northern California, United States 37 Nevada, United States 3X Off coast of California, United States 39 Central California, United States 40 California-Nevada border region 41 Southern Nevada, United States 42 Western Arizona. United States 43 Southern California, United States 44 California-Arizona border region 45 California-Baja California border region 46 Western Arizona-Sonora border region

4 BAJA CALlFORNIA AND GULF OF CALIFORNIA

47 Off west coast of Baja California, Mexico 4X Baja California. Mexico 49 Gulf of California, Mexico SO Sonora, Mexico 51 Off coast of central Mexico 52 Near coast of central Mexico

5 MEXICO - GUATEMALA AREA 53 Revilla Gigedo Islands, Mexico, region 54 Off coast of Jalisco, Mexico 55 Near coast of Jalisco. Mexico 56 Near coast of Michoacan, Mexico 57 Michoacan, Mexico 58 Near coast of Guerrero, Mexico 59 Guerrero. Mexico 60 Oaxaca, Mexico 61 Chiapas, Mexico 62 Mexico-Guatemala border region

$ 63 Off coast of Mexico

64 Off coast of Michoacan, Mexico 65 Off coast of Guerrero, Mexico 66 Near coast of Oaxaca, Mexico 67 Off coast of Oaxaca, Mexico 6X Off coast of Chiapas, Mexico 69 Near coast of Chiapas, Mexico 70 Guatamala 71 Near coast of Guatemala

I 730 Northern East Pacific Rise

6 CENTRAL AMERICA 72 Honduras 73 El Salvador 74 Near coast of Nicaragua 75 Nicaragua 76 Off coast of central America 77 Off coast of Costa Rica 7X Costa Rica 79 North of Panama X0 Panama-Costa Rica border region 81 Panama X2 Panama-Colombia border region X3 South of Panama

7 CARIBBEAN LOOP X4 Yucatan Peninsula, Mexico 85 Cuba region 86 Jamaica region X7 Haiti region 8X Dominican Republic region 89 Mona Passaga 90 Puerto Rico region 9 1 Virgin Islands 92 Leeward Islands 93 Belize

$ 94 Caribbean Sea 9.5 Windward Islands 96 Near north coast of Colombia 97 Near coast of Venezuela 98 Trinidad 99 Northern Colombia

100 Lake Maracaibo, Venezuela 10 1 Venezuela

I 731 North of Honduras

8 ANDEAN SOUTH AMERICA 102 Near west coast of Colombia 103 Colombia

289

104 Off coast of Ecuador 105 Near coast of Ecuador I 06 Colombia-Ecuador border region 107 Ecuador 108 Off coast of northern Peru 109 Near coast of northern Peru 110 Peru-Ecuador border region 111 Northern Peru 112 Peru-Brazil border region 113 Western Brazil 114 Off coast of Peru 115 Near coast of Peru 1 16 Central Peru 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142

Southern Peru Peru-Bolivia border region Northern Bolivia Central Bolivia Off coast of northern Chile Near coast of northern Chile Northern Chile Chile-Bolivia border region Southern Bolivia Paraguay Chile-Argentina border region Jujuy Province, Argentina Salta Province, Argentina Catamarca Province. Argentina Tucuman Province. Argentina Santiago del Ester0 Province, Argentina Northeastern Argentina Off coast of central Chile Near coast of central Chile Central Chile San Juan Province, Argentina La Rioja Province. Argentina Mendoza Province. Argentina San Luis Province. Argentina Cordoba Province. Argentina Uruguay

9 EXTREME SOUTH AMERICA I 43 Off coast of southern Chile 144 Southern Chile 145 Southern Chile-Argentina border region I46 Southern Argentina

10 SOUTHERN ANTILLES 147 Tierra de1 Fuego 14X Falkland Islands region

149 150 151 152 153 154 15s

S 156 157

I 732

11 15x

Drake Passage Scotia Sea South Georgia lsland region South Georgia Rise South Sandwich Islands region South Shetland Islands Antarctic Peninsula Southwestern Atlantic Ocean Weddell Sea East of South Sandwich Islands

NEW ZEALAND AREA Off west coast of North Island, New Zealand

159 160

North Island. New Zealand Off east coast of North Island, New Zealand

161 Off west coast of South Island, New Zealand

162 163 164

South Island, New Zealand Cook Strait. New Zealand Off east coast of South Island, New Zealand

165 North of Macquarie Island 166 Auckland Islands. New Zealand, region 167 Macquarie Island. Australia. region 16X South of New Zealand

12

169 170 171

* 172

173 174 175

KERMADEC - TONGA - SAMOA BASIN AREA Samoa Islands region Samoa Islands South of Fiji Islands West of Tonga Islands (REGION NOT IN USE) Tonga Islands Tonga Islands region South of Tonga Islands

176 North of New Zealand 177 Kermadec islands region 17X Kermadec Islands. New Zealand 179 South of Kermadec Islands

13 FIJI ISLANDS AREA 1X0 North of Fiji Islands IX1 Fiji Islands region 1X2 Fiji Islands

290 J.B. Young et ul./Physi~~ oj’the Earth md Planetury Interiors 96 (1996) 223-297

14 VANUATU ISLANDS 183 Santa Cruz Islands region 184 Santa Cruz Islands 185 Vanuatu Islands region 186 Vanuatu Islands 187 New Caledonia 188 Loyalty Islands 189 Southeast of Loyalty Islands

15 BISMARCK AND SOLOMON ISLANDS

190 New Ireland, Papua New Guinea, region 191 North of Solomon Islands 192 New Britain, Papua New Guinea, region 193 Bougainville - Solomon Islands region 194 D’Entrecasteaux Islands, Papua New

Guinea, region 195 South of Solomon Islands

16 NEW GUINEA AREA 196 Irian Jaya, Indonesia, region 197 Near north coast of Irian Jaya, Indonesia 198 Ninigo Islands, Papua New Guinea,

region 199 Admiralty Islands, Papua New Guinea,

region 200 Near north coast of New Guinea, Papua

New Guinea 201 Irian Jaya, Indonesia 202 New Guinea, Papua New Guinea 203 Bismarck Sea 204 Am Islands, Indonesia, region 205 Near south coast of Irian Jaya, Indonesia 206 Near south coast of New Guinea, Papua

New Guinea 207 Eastern New Guinea, Papua New Guinea,

region 208 Arafura Sea

17 CAROLINE ISLANDS TO GUAM 209 Western Caroline Islands, Micronesia 210 South of Mariana Islands

18 GUAM TO JAPAN 211 Southeast of Honshu, Japan 212 Bonin Islands, Japan, region 2 13 Volcano Islands, Japan, region 214 West of Mariana Islands

2 15 Mariana Islands region 2 16 Mariana Islands

19 JAPAN - KURIL ISLANDS - KAMCHATKA PENINSULA

2 17 Kamchatka Peninsula, Russia 218 Near east coast of Kamchatka Peninsula,

Russia 219 Off east coast of Kamchatka Peninsula,

Russia 220 Northwest of Kuril Islands, Russia 221 Kuril Islands, Russia 222 East of Kuril Islands, Russia 223 Eastern Sea of Japan 224 Hokkaido, Japan, region 225 Off southeast coast of Hokkaido, Japan 226 Near west coast of eastern Honshu, Japan 227 Eastern Honshu, Japan 228 Near east coast of eastern Honshu, Japan 229 Off east coast of Honshu, Japan 230 Near south coast of eastern Honshu, Japan

20 SOUTHWESTERN JAPAN AND RYUKYU ISLANDS

231 South Korea 232 Western Honshu, Japan 233 Near south coast of western Honshu,

Japan 234 Northwest of Ryukyu Islands, Japan 235 Kyushu, Japan 236 Shikoku, Japan 237 Southeast of Shikoku, Japan 238 Ryukyu Islands, Japan 239 Southeast of Ryukyu Islands, Japan 240 West of Bonin Islands, Japan 241 Philippine Sea

21 TAIWAN 242 Near coast of southeastern China 243 Taiwan region 244 Taiwan 245 Northeast of Taiwan 246 Southwestern Ryukyu Islands, Japan 247 Southeast of Taiwan

22 THE PHILIPPINES 248 Philippine Islands region 249 Luzon, Philippine Islands

J.B. Young et al./ Phy.ws of the Earth und Plunettrry Interiors 96 (1996) 223-297 291

250 Mindoro, Philippine Islands 251 Samar, Philippine Islands 252 Palawan, Philippine Islands 253 Sulu Sea 254 Panay, Philippine Islands 255 Cebu, Philippine Islands 256 Leyte, Philippine Islands 257 Negros, Philippine Islands 258 Sula Archipelago, Philippine Islands 259 Mindanao, Philippine Islands 260 East of Philippine Islands

23 BORNEO - SULAWESI 261 Borneo 262 Celebes Sea 263 Talaud Islands, Indonesia 264 North of Halmahera, Indonesia 265 Minahassa Peninsula, Sulawesi, Indonesia 266 Northern Molucca Sea 267 Halmahera, Indonesia 268 Sulawesi, Indonesia 269 Southern Molucca Sea 270 Ceram Sea 271 Bunt, Indonesia 272 Seram, Indonesia

24 SUNDA ARC 273 Southwest of Sumatera, Indonesia 274 Southern Sumatera, Indonesia 275 Java Sea 276 Sunda Strait, Indonesia 277 Jawa, Indonesia 278 Bali Sea 279 Flores Sea 280 Banda Sea 281 Tanimbar Islands, Indonesia, region 282 South of Jawa, Indonesia 283 Bali, Indonesia, region 284 South of Bali, Indonesia 28.5 Sunbawa, Indonesia, region 286 Flares, Indonesia, region 287 Sumba, Indonesia, region 288 Savu Sea 289 Timor, Indonesia, region 290 Timor Sea 291 South of Sumbawa, Indonesia 292 South of Sumba, Indonesia 293 South of Timor, Indonesia

25 MYANMAR AND SOUTHEAST ASIA 294 Myanmar-India border region 295 Myanmar-Bangladesh border region 296 Myanmar 297 Myanmar-China border region 298 Near south coast of Myanmar

* 299 Southeast Asia (REGION NOT IN USE) 300 Hainan Island, China 301 South China Sea

I 733 Thailand I 734 Laos I 735 Kampuchea I 736 Vietnam I 737 Gulf of Tongking

26 INDIA - XIZANG - SICHUAN - YUNNAN

302 Eastern Kashimir 303 Kashmir-India border region 304 Kashmir-Xizang border region 305 Western Xizang-India border region 306 Xizang 307 Sichuan, China 308 Northern India 309 Nepal-India border region 310 Nepal 311 Sikkim, India 312 Bhutan 3 13 Eastern Xizang-India border region 3 14 Southern India 3 15 India-Bangladesh border region 3 16 Bangladesh 3 17 Northeastern India 3 18 Yunnan, China 319 Bay of Bengal

27 SOUTHERN XINJIANG TO GANSU 320 Kyrgyzstan-Xinjiang border region 321 Southern Xinjiang, China 322 Gansu, China 323 Western Nei Mongol, China 324 Kashmir-Xinjiang border region 325 Qinghai, China

28 LAKE ISSYK-KUL TO LAKE BAYKAL

326 Southwestern Siberia, Russia 327 Lake Baykal, Russia, region

328 East of Lake Baykal. Russia 329 Eastern Kazakhstan 330 Lake Issyk-Kul, Kyrgyzstan, region 33 I Kazakhstan-Xinjiang border region 332 Northern Xinjiang, China 333 Tuva-Buryatia-Mongolia border region 334 Mongolia

29 WESTERN ASIA 335 Ural Mountains, Russia, region 336 Western Kazakhstan 337 Eastern Caucasus 338 Caspian Sea 339 Northwestern Uzbekistan 340 Turkmenistan 341 Iran-Turkmenistan border region 342 Turkmenistan-Afghanistan border region 343 Turkey-Iran border region 344 Iran-Armenia-Azerbaijan border region 345 Northwestern Iran 346 Iran-Iraq border region 347 Western Iran 348 Northern and central Iran 349 Northwestern Afghanistan 350 Southwestern Afghanistan 351 Eastern Arabian Peninsula 352 Persian Gulf 353 Southern Iran 354 Southwestern Pakistan 35.5 Gulf of Oman 356 Off coast of Pakistan

30 MIDDLE EAST - CRIMEA - EASTERN BALKANS

357 Ukraine - Moldova - Southwestern Russia region

358 Romania 359 Bulgaria 360 Black Sea 361 Crimea, Ukraine, region 362 Western Caucasus 363 Greece-Bulgaria border region 364 Greece 365 Aegean Sea 366 Turkey 367 Turkey-Georgia-Armenia border region 368 Southern Greece 369 Dodecanese Islands. Greece

370 Crete, Greece 371 Eastern Mediterranean Sea 372 Cyprus region 373 Dead Sea region 374 Jordan - Syria region 375 Iraq

31 WESTERN MEDITERRANEAN SEA AREA

376 Portugal 377 Spain 378 Pyrenees 379 Near south coast of France 380 Corsica, France 381 Central Italy 382 Adriatic Sea 383 Northwestern Balkan Peninsula 384 West of Gibraltar 385 Strait of Gibraltar 386 Balearic Islands, Spain 387 Western Mediterranean Sea 388 Sardinia, Italy 389 Tyrrhenian Sea 390 Southern Italy 39 1 Albania 392 Greece-Albania border region 393 Madeira Islands, Portugal, region 394 Canary Islands, Spain, region 395 Morocco 396 Northern Algeria 397 Tunisia 398 Sicily, Italy 399 Ionian Sea 400 Central Mediterranean Sea 401 Near coast of Libya

32 ATLANTIC OCEAN $ 402 North Atlantic Ocean

403 Northern Mid-Atlantic Ridge 404 Azores Islands region 405 Azores Islands. Portugal 406 Central Mid-Atlantic Ridge 407 North of Ascension Island 408 Ascension Island region 409 South Atlantic Ocean 410 Southern Mid-Atlantic Ridge 41 1 Tristan da Cunha region 412 Bouvet Island region

293

413 Southwest of Africa 414 Southeastern Atlantic Ocean

I 73X Reykjanes Ridge I 739 Azores-Cape St. Vincent Ridge

33 INDIAN OCEAN 4 I5 Eastern Gulf of Aden 4 I6 Socotra region

$ 4 I7 Arabian Sea 4 1X Lakshadweep. India. region 419 Northeastern Somalia 420 North Indian Ocean 421 Carlsberg Ridge 422 Maldive Islands region 423 Laccadive Sea 424 Sri Lanka

s 425 South Indian Ocean 426 Chagos Archipelago region 427 Mauritius - Reunion region 42X Southwest Indian Ridge 429 Mid-Indian Ridge 430 South of Africa 43 1 Prince Edward Islands. South Africa.

region 432 Crozet Islands region 433 Kerguelen Islands region 434 Broken Ridge 435 Southeast Indian Ridge 436 Southern Kerguelen Plateau

;” 437 South of Australia 740 Owen Fracture Zone region

I 741 Indian Ocean Triple Junction I 742 Western Indian-Antarctic Ridge

34 EASTERN NORTH AMERICA 43X Saskatchewan, Canada 439 Manitoba, Canada 440 Hudson Bay 441 Ontario. Canada 442 Hudson Strait, Canada, region 443 Northern Quebec. Canada 444 Davis Strait 445 Labrador, Canada 446 Labrador Sea 447 Southern Quebec, Canada 44X Gaspe Peninsula. Canada 449 Eastern Quebec. Canada 450 Anticosti Island, Canada

451 New Brunswick, Canada 452 Nova Scotia. Canada 453 Prince Edward Island, Canada 454 Gulf of St. Lawrence, Canada 45.5 Newfoundland, Canada 456 Montana, United States 457 Eastern Idaho. United States 458 Hebgen Lake, Montana, United States,

region 459 Yellowstone, United States. region 460 Wyoming, United States 461 North Dakota, United States 462 South Dakota, United States 463 Nebraska, United States 464 Minnesota, United States 465 Iowa. United States 466 Wisconsin, United States 467 Illinois. United States 468 Michigan, United States 469 Indiana, United States 470 Southern Ontario, Canada 471 Ohio, United States 472 New York, United States 473 Pennsylvania, United States 474 Vermont - New Hampshire, United

States, region 475 Maine. United States 476 Southern New England, United States 477 Gulf of Maine, United States 47X Utah, United States 479 Colorado, United States 4X0 Kansas, United States 48 I Iowa-Missouri border region 4X2 Missouri-Kansas border region 4X3 Missouri. United States 484 Missouri-Arkansas border region 485 Missouri-Illinois border region 4X6 New Madrid. Missouri, United States,

region 4X7 Cape Girardeau, Missouri, United States,

region 488 Southern Illinois, United States 4X9 Southern Indiana, United States 490 Kentucky, United States 491 West Virginia. United States 492 Virginia. United States 493 Chesapeake Bay, United States, region 494 New Jersey, United States

294 J.B. Young et ul./Phy.sics of‘rhe Earth und Planetury Interiors 96 (1996) 223-297

495 Eastern Arizona, United States 496 New Mexico, United States 497 Northwestern Texas-Oklahoma border

region 498 Western Texas, United States 499 Oklahoma, United States 500 Central Texas, United States 501 Arkansas-Oklahoma border region 502 Arkansas, United States 503 Louisiana-Texas border region 504 Louisiana, United States 505 Mississippi, United States 506 Tennessee, United States 507 Alabama, United States 508 Western Florida, United States 509 Georgia, United States 5 10 Florida-Georgia border region 511 South Carolina, United States 512 North Carolina, United States 5 13 Off east coast of United States 5 14 Florida Peninsula, United States 5 15 Bahama Islands 5 16 Eastern Arizona-Sonora border region 517 New Mexico-Chihuahua border region 5 18 Texas-Mexico border region 5 19 Southern Texas, United States 520 Near coast of Texas, United States 521 Chihuahua, Mexico 522 Northern Mexico 523 Central Mexico 524 Jalisco, Mexico 525 Veracruz, Mexico 526 Gulf of Mexico 527 Bay of Campeche

35 EASTERN SOUTH AMERICA 528 Brazil 529 Guyana 530 Suriname 531 French Guiana

36 NORTHWESTERN EUROPE 532 Eire 533 United Kingdom 534 North Sea 535 Southern Norway 536 Sweden 537 Baltic Sea

538 France 539 Bay of Biscay 540 The Netherlands 541 Belgium 542 Denmark 543 Germany 544 Switzerland 545 Northern Italy 546 Austria 547 Czech and Slovak Republics 548 Poland 549 Hungary

37 AFRICA * 550 Northwest Africa (REGION NOT IN

USE) 55 1 Southern Algeria 552 Libya 553 Egypt 554 Red Sea 555 Western Arabian Peninsula 556 Chad region 557 Sudan 558 Ethiopia 559 Western Gulf of Aden 560 Northwestern Somalia 561 Off south coast of northwest Africa 562 Cameroon 563 Equatorial Guinea 564 Central African Republic 565 Gabon 566 Congo 567 Zaire 568 Uganda 569 Lake Victoria region 570 Kenya 571 Southern Somalia 572 Lake Tanganyika region 573 Tanzania 574 Northwest of Madagascar 575 Angola 576 Zambia 577 Malawi 578 Namibia 579 Botswana 580 Zimbabwe 58 1 Mozambique 582 Mozambique Channel

J.B. Young et d/Physics of’the Earth und Plunetury Interiors 96 (1996) 223-297 295

583 Madagascar 584 South Africa 585 Lesotho 586 Swaziland 587 Off coast of South Africa 743 Western Sahara 744 Mauritania 745 Mali 746 Senegal - Gambia region 747 Guinea region 748 Sierra Leone 749 Liberia region 750 Cote d’Ivoire 75 1 Burkina Faso 752 Ghana 753 Benin - Togo region 754 Niger 755 Nigeria

38 AUSTRALIA 588 Northwest of Australia 589 West of Australia 590 Western Australia 591 Northern Territory, Australia 592 South Australia 593 Gulf of Carpentaria, Australia 594 Queensland, Australia 595 Coral Sea 596 Northwest of New Caledonia 597 New Caledonia region 598 Southwest of Australia 599 Off south coast of Australia 600 Near coast of South Australia 601 New South Wales, Australia 602 Victoria, Australia 603 Near southeast coast of Australia 604 Near east coast of Australia 605 East of Australia 606 Norfolk Island, Australia, region 607 Northwest of New Zealand 608 Bass Strait, Australia 609 Tasmania, Australia, region 610 Southeast of Australia

39 PACIFIC BASIN 41 ASIA SEA 611 North Pacific Ocean 656 Southeastern Siberia, Russia 612 Hawaiian Islands region 657 Priamurye-Northeastern China border 613 Hawaiian Islands, United States region 6 14 Eastern Caroline Islands, Microne 658 Northeastern China

region 615 Marshall Islands region 616 Enewetak Atoll, Marshall Islands, region 617 Bikini Atoll, Marshall Islands, region 618 Gilberg Islands, Kiribati, region 619 Johnston Island region 620 Line Islands, Kiribati, region 621 Palmyra Island, Kiribati, region 622 Kiritimati, Kiribati, region 623 Tuvalu region 624 Phoenix Islands, Kiribati, region 625 Tokelau Islands region 626 Northern Cook Islands 627 Cook Islands region 628 Society Islands region 629 Tubuai Islands region 630 Marquesas Islands region 631 Tuamotu Archipelago region 632 South Pacific Ocean

40 ARCTIC ZONE 633 Lomonosov Ridge 634 Arctic Ocean 635 Near north coast of Kalaallit Nunaat 637 Iceland region 638 Iceland 639 Jan Mayen Island region 640 Greenland Sea 641 North of Svalbard 642 Norwegian Sea 643 Svalbard, Norway, region 644 North of Franz Josef Land 645 Franz Josef Land, Russia 646 Northern Norway 647 Barents Sea 648 Novaya Zemlya, Russia 649 Kara Sea 650 Near coast of northwestern Siberia,

Russia 651 North of Sevemaya Zemlya 652 Sevemaya Zemlya, Russia 653 Near coast of northern Siberia, Russia 654 East of Sevemaya Zemlya 655 Laptev Sea

296

659 North Korea 660 Sea of Japan 661 Primorye. Russia 662 Sakhalin Island, Russia 663 Sea of Okhotsk 664 Southeastern China 665 Yellow Sea 666 Off east coast of southeastern China

42

667 668 669 670

671 672 673 674 675 676 677 678 679 680 681 682

NORTHEASTERN ASIA, NORTHERNALASKATO GREENLAND North of New Siberian Islands New Siberian Islands, Russia Eastern Siberian Sea Near north coast of eastern Siberia. Russia Eastern Siberia. Russia Chukchi Sea Bering Strait St. Lawrence Island. United States, region Beaufort Sea Northern Alaska, United States Northern Yukon Territory, Canada Queen Elizabeth Islands, Canada Northwest Territories. Canada Western Kalaallit Nunaat Baffin Bay Baffin Island, Canada, region

43

683 684 68.5 686 687 688 689 690 691

: 692 756

SOUTHEASTERN AND ANTARCTIC PACIFIC OCEAN Southeastcentral Pacific Ocean Southern East Pacific Rise Easter Island region West Chile Rise Juan Femandez Islands. Chile, region East of North Island, New Zealand Chatham Islands, New Zealand, region South of Chatham Islands Pacific-Antarctic Ridge Southern Pacific Ocean Southeast of Easter Island

44 GALAPAGOS AREA $ 693 Eastcentral Pacific Ocean

694 Central East Pacific Rise

695 West of Galapagos Islands 696 Galapagos Islands region 697 Galapagos Islands. Ecuador 698 Southwest of Galapagos Islands 699 Southeast of Galapagos Islands

I 757 Galapagos Triple Junction region

45 MACQUARIE LOOP 700 South of Tasmania 70 I West of Macquarie Island 702 Balleny Islands region

46

703 704 705

706 707 708

ANDAMAN ISLANDS TO SUMATERA Andaman Islands, India, region Nicobar Islands, India, region Off west coast of northern Sumatera, Indonesia Northern Sumatera, Indonesia Malay Peninsula Gulf of Thailand

47 BALUCHISTAN 709 Southeastern Afghanistan 710 Pakistan 711 Southwestern Kashmir 712 India-Pakistan border region

48 HINDU KUSH AND PAMIR 713 Central Kazakhstan 714 Southeastern Uzbekistan 715 Tajikistan 716 Kyrgyzstan 717 Afghanistan-Tajikistan border region 718 Hindu Kush, Afghanistan, region 719 Tajikistan-Xinjiang border region 720 Northwestern Kashmir

49 721 722 723 724

NORTHERN EURASIA Finland Norway-Murmansk border region Finland-Karelia border region Baltic States - Belarus - Northwestern Russia region

725 Northwestern Siberia, Russia 726 Northern and central Siberia, Russia

50 ANTARCTICA 727 Victoria Land. Antarctica 728 Ross Sea 729 Antarctica

5 I 730

7 I 731

10 I 732

2s I 733 I 734

735 736 737

MEXICO - GUATEMALA AREA Northern East Pacific Rise

CARIBBEAN LOOP North of Honduras

SOUTHERN ANTILLES East of South Sandwich Islands

MYANMAR AND SOUTHEAST ASIA Thailand Laos Kampuchea Vietnam Gulf of Tongking

32 I 738 I 739

ATLANTIC OCEAN Reykjanes Ridge Azores-Cape St. Vincent Ridge

33 INDIAN OCEAN 740 Owen Fracture Zone region 741 Indian Ocean Triple Junction 742 Western Indian-Antarctic Ridge

37 AFRICA 743 Western Sahara 744 Mauritania 745 Mali 746 Senegal - Gambia region 747 Guinea region 748 Sierra Leone 749 Liberia region 750 Cote d’Ivoire 751 Burkina Faso 752 Ghana 753 Benin - Togo region

I 754 Niger I 755 Nigeria

43 SOUTHEASTERN AND ANTARCTIC PACIFIC OCEAN

I 756 Southeast of Easter Island

44 GALAPAGOS AREA I 757 Galapagos Triple Junction region

Key I New Geographical region. $ Geographical Region Reduced in Size. * Geographical Region No Longer in Use.

References

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