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bY R aphael U nrug T he assem bly of G ondw analand Scientif c results of IG C P P rQject 288: G ondw analand sutures and m obile belts

(follellvallelland ;, · ‘,‘、elssellibled ill lhe 从1OP roterozoic IG C JI Project 288 (w nd lvem aland m au,一‘)、‘,,,‘//了,/‘/j,。/1八 P an A.11-ican-B rtisdiano orogem 介)How ilig breakup ‘,广 (199()一1995, extended in 1990 ) asscm N ed :、larl-e and di\ci-,,c IILIIII- he'- Of PM-ticilM lIts. Ik Ullk-d I-Cl2io)nal studies conducted ill }111 ex- 1/](夕/)1沼〔‘(,‘/ti,‘留R odinia supercontilicia. The hiller created G o nd -A m ialand SOU 山ern co n tinen ts }}e re s\ n the siscd in the G cot卜- ond 、‘1 1/1 illolioll。,iiew sYm em ‘夕'11tilospheric philes that nam ic m ap ()!( ;olldw allalalld 八、scm hk I)FOCILICCLI jOilltIN' h}r IG C P ir vithed ill Ilie,101-Inaltoti o)"N eop rolet-o-P ic m obile bell.% Pro,ject 288 W alahasc Icnel-aliojn), Ole C otincil fol- (W OSCIence, Pre- t0l-lil, SOLIth A frica (G IS and digital cartoyr}tph} ), and the B UI-CM I (IC slllllrinl} old crolotis ill G ondivanalm id. L ast G ontA valiti- R echcrches G cO1OI1M(jLleS Ct M illic[-C',, 0 1-1}Z111, FI-M ICC (pl'illtillO . III land w as a .11-op tient ol that survived the addition to the in}甲.W hich is 山C IW IJOI- OLIICOIIIC 01' I(A P 288. the /”,、akitp alid, du,一,it,, the N vop roiero -oi( 、、,‘,.、a/.} ec,c ted pro,ject achicved im portant rem ilt、川 1-c I'i川ng the Concept of ‘,,,/、,bY I'llta lcolitt.n e l lia八 eloritialion. Ill M }st G o,ntlw a- R odinia 一[he ';llj)Cl-COlItillCllt I)I-CCUI-Sol- to (iondw ana, datim-, ]hc crc- ation of 山C P}W ihC O CCM I, M Id CIC\Clol)ill,( h\j)OthCSeS Oll C}ILISCS Of lioloild, 1/1( ‘,/,‘nin"', ‘,/th,二。‘,(calls, I)-olll w hich Poll 山e %0 despread dccrat()川、atioll 。)!old continental crust fragm ents A lO call-B ra'siliallo orogeivs w ere bot-11, Is traced to a and postoroLcnic m aom ati,,m in the Pan 八frican- 131%i,,ih,m o period ol,crustal c.vicilsioll, ri/? illg, trallspi-cssioll. OR )gc 11y Plo "' Ie s " low ards solvim-,山。G ollkk}allalalld asscillbly puzzle jiltil(c aa activitv, ond (I八、,、docum ented lerralW ('0111- w as rapid. ReLional s} nthesc,, (T ionipcitc, 1994} S11-11111), 1995 ) siL- }iolls (/000 刃0 M a ), brockeled bY R othnia a,s,}em hlv nificall(k, }1(k zlllccd ulldelsiallding the evolution of' ituportalit parts tind breakup.八/八'raloll collisioll、illvolvilig clo wli-c (,/ of, G olidw allalaild. Flic Icadci I,., rcleri-cd to the transctipt ol'an open f'Ol-LIIII ClISCLISSIOll held :I t the 8th livernational G ond}}ana Syiupo- OCCOILS, (04()-590 M a ),postelate the Rodinia bi-cakup M UM ill11、)卜:Irt l:1、111:川1:1(1〕、)w o11. 1 9 93)LInd rc%ic A,s(U uI-U0, 1992二 A e Pail A /1-icai,-B rasiliavio orogeti1v (72()一-5-50 Ala) is R ogCI 'S , 以al,1995二、oshickt, I‘)95)101- }tCCOLIIHI, OF file C%ol、厂i ll9 ,、‘/‘·万lied to illclude otll\, the colli.sioll一,-clated ideas. T his paper prescnts the nlilill I)Oilll', 01 CLIITClu \ iCIA 1, Oil G oll- tion, }hcariii,} and tectoiiic escape, and synorogetuc & A ana land a,,se m b ly as ‘){ 19 96 . R c le re nccs are m adc to rece nt JXIPCI-S l)LIhli1,lICd (ILHAW-1 the file Of lG C P P1-OjCCt -188. inaginatisill pm Idatilig the R othilia breakup . livo m odels /,‘,、】‘乃。、,,p roposed 八,,posloro,}ellic ,,,‘,;,,1‘,It‘、,,1 a l lel liplili, w ith"Sp i-cad ill G oildw allaltilld: lithosplicric 171011- F rom R odinia to G ondw ana to P angea fl e d ela inina tio n ca used In co nlilienta 八'0 11i'v o ll ill W est (joildw allalaild alld itildcl-ploling of busallic intigilla ill G oildw allakuld ori-illated LlUI-iI1L the N copro(cro/oic Pan A trican- 111-}ISili,1110 OIOLIC]IiCS (FiLLII-C I)tlM l I-C}UhCd in occan Closure and Eo.st G ond waiialan(L Lvotopic studies suggest large- M ITTW I}-Icnlcllt, collision, alld 141ti-11-111I0 of oldcr continental crust scah, addi'11011 。,/S111)(Irgent, w ater to hot ‘rust in Ihe,se fi-}ILIIIICIIIS PI-OdLICCd hy hi-cakup ()!the piccurso,I . sUPCI-COntHieut post 0roge/lu el'Clits. 刀,‘,(vs,w inb/v ot'G ondtvaiialm id R o d in ia. T he d em ise o l' R od inia and 1'0 1-111}tliO ll 01 C o nd w ana land is convenicnily clesciihed ill term s of the st-II)CI-ColltilICIA cycle. A p rocet,dcd b-N, elockin,cl, of individuol。二,tolis aild Ihe,二is SUPCIVOlItille'll I,, (IC1111C(I hy its :I SSCHIM 11111 111oh',il OFOLIelly. -1he ,,(,evidem -e (,/one collisim i betw (‘,,,M e,vi w id Ea st 6 011- hi-cakLIP P}IRCI-ll Of file pI-CCLII-SOr SUI)CICOlItHICIlt reshapes for dwalialatid. Aft er die ossem b/Y of'G om ilw analand, te( the next cycle. III a cycle the breakup Of M l OldCl- SLI11CI-CO111111CIII illid LICCICtiO)) 01:、IIC\k supel-contillclit o%,Cl-l:tp ill tillic toiiic and m aginw ic activitY ‘v h}ft ed to the accretionar.N but [lot ill "Pace. Poc}fi - m argin, and (it the sam e litne rifi ng w id calving Rodinia w it s a s sem bled by late M CS()P]-()ICI()Z()IC (13M )一!()()() 0/ tel,·‘,,,。、‘,。·(elerated tit the opposite m ar,}m ‘,厂thc M il) ol-oL'Cllics that produced tile SvcC()一N orw e,gian, G renville, Sri,,- sup erco ii t ii i e i it. 、:、、、K ibaran, N am aqua -N iilal, M aLldheim , I'd ozanibiqUe, Eastern G hats, A lbany, Frascr, Paterson-M u,}gIra\c, noith-easl A LISO'ali}、一 Y angt/.e-C alhaysia and K irim ping m obile bells (I"i"Ure 2). T he brcakup 01'LaLlrelltia I'l-0111 F aSt A ntarctica and A L IS t ra lia to create tire Pacific O cean- the first m ajor eveni ill Rodinia disinte- In tro d u ctio n grati oil一 w its dated on palcom aIgnetic dirta ill }20 M 川 low ell et al., 1993, Pow ell, and LA, 1994h). floffirian (!99 1)proposed that the H istorically. G ondw analand lias been a 化I-tilC fiCld Ot'SILICly. E m ei- hreakUp 、)!LaUl-ClIlia from R odinia initiated the supercontinent octice ol'the ne\N paradigni ol' brought appreciation of l-CCOllh,('Uration that reA llted ill the lorm ation ol G ondw analand. J he the cal-1v syntheses of, Suess (1985), W c-ccncr (19 15), and IJU T oit breakUp ot R odinia w as preceded by (lie form ation of and sag (193 7 ). th at w ere ahc ad o t th eir linic . and rev ive d interest ill G o n- hiisins, illtlaco)litillcillid m obile hells, passive filarl"ills, itird m agm atic (1\} }111;lkfl d ICC0)IISIFUCtiOlI h}tsed on inarine geophysics. T he G colog- arcs that w ere later kivolved ill tire assem bly ol' G ondw analand ical M ap of Sector,, ofJ iondw ana (de W it, 1988 ) focused oil Cl-USM I 'f 111.11, tile bl-Cakup of Rodinia and a}scm bly ol G ondw analand " ere extension preceding the M esozoic breakup of G ondw analand and partly coeval (I"i"Llre 3). (;ondw analand assem bly w il'} com plete by Initiation ()‘sedim entary hasins alonIo (lie passi\c niargins()【present e;ji-liest Palcozoic little. 'I’h CrC COLIJO IKIVC bCCll::},Cojol-icajjy Ilect- e x 一(io n d \v a n a la n d c o u lu ie n ts - Ill'-' little }NhCll LaLlICII(M \&it, still joined w ith S iberia air(] B altica h"p i,w d,、.V o l. 11), nos. / & ) 1 2

F igure I G o n d w a n alan d cra to n s a n d 乃oterozoic m ohile C a d o m ia n b e lts .

A va lo n ian

P ac ific M argin

赢 摹摹摹 M esoproterozoic m o bile belts A rchean 一Paleoproterozoic c ra to n s

瓢馨 N eoproterozoic m obile belts _.i}瓢 N eoproterozoic

A rc h e a n a n d P r o te ro z o ic cr a to n s : N eoproterozoic m obile belts: 14 A raguaia 2 7 K a o k o A IVIZ A m azonian 1 M a u re ta n id e s 1 5 G o ia s 2 8 D a m a ra B D K B u ndelkhand 2 B a ssa rid es 1 6 B ra silia 2 9 L u fi lia n C NG Congo 3 R o c k e lid e s 17 Param irim 30 Kundelungu aulacogen EAG East A ntarctica-G awler 4 A n ti A tlas 1 8 A rac u a i 30aB u koban aulacogen E S N E ast Sahara- N ile 5 O ugata aulacogen 19 W est Congo 3 1 Z a m b e z i KG K alahari-Grunehogna 6 T ran s-S ah a ra n 20 Sangha aulacogen 32 G ariep M D M adagascar-Dharw ar 7 T ib e sti 2 1 T u c a va c a 3 3 S a ld an ia N A N orth A u stralian 8 G ourm a aulacogen 22 Paraguay-C ordoba 3 4 B e ard m o re R L P R io de la Plata 9 D ah o rn eid e s 23 Pam pean Ranges 35 Pinjarra S Salvador 10 N igeria 23aN orthern Patagonia 3 6 A d elaid e S F Sao Francisco 1 1 B o rb o re rn a 2 4 R ib e ira 37 Patterson- Peterm an R anges W A W est Australian 12 Sergipe-O ubanguide 2 5 R io D o c e W A F W est A frican 1 3 A N E K T 2 6 D o m F e lic ia n o

w as in contact w ith the A m azon ia a nd R io d e la P lata crato n s and th e rest of G ondw analand, to form a latest N eoproterozoic superconti- G eodynam ic provinces of G ondw analand nent (Pow ell, 1995). W hilst addition of N eoproterozoic juvenile continental crust w as im portant in several of G ond- Paleom agnetic data, and age of suturing by m obile belts, perm it the w ana, other regions w ere affected by intracontinental tectonic d istinc tion b etw een an E ast an d a W est G o nd w an alan d w ith con - events. A fter the N eoproterozoic ocean closures in the Pan A frican trasting N eoproterozoic histories. The form er, w hich com prised the and B rasiliano, , Palcozoic form ation of m arginal G ond- K alahari-G runehogna of A frica and East A ntarctica, M ada- w anide accretionary orogens along the paleo-Pacific m argin of G on- gascar, India, A ntarctica, and A ustralia, w as a surviving fragm ent of dw analand, brief collisions of G ondw analand and L aurentia in the O rdovician and D evonian (D alziel et aL, 1993; 1994) and the late the preceding M esoproterozoic R odinia supercontinent that escaped breakup and rem ained coherent until the M esozoic breakup of G on- Paleozoic collision w ith L aurussia to form Pangea, did not change significantly the internal structure of G ondw analand. C alving of ter- dw analand (U nrug, 1992; 1994). It consisted ofa num ber of A rcbean ranes from the paleo-T ethys m argin of G ondw analand and T riassic and Paleoproterozoic cratons sutured by M esoproterozoic m obile deform ation of the intracontinental V entana-C ape fold belt and its belts. W est G ondw analand included a num ber ofA rchean-Paleopro- extension as a foreland fold and thrust belt through A ntarctica and terozoic cratons sutured by late N eoproterozoic m obile belts. In the eastern A ustralia, heralded the onset of M iddle T riassic breakup of R odinia reconstruction the W est G ondw ana cratons: W est A frican, Pangea. T his interpretation, the best available presently, is condi- A m azom an and R io de la Plata w ere separated from the future East tioned by incom plete know ledge of M esoproterozoic and N eopro- G ondw ana craton assem blage by the L aurentian craton (H offm an, terozoic events, especially in A ntarctica. 1991). A valom an (N ance and M urphy, 1994), and C ado-

M a rch & Jun e 19 96 了3

A rch e a n a n d M esoproterozoic M E S O P R O T E R O Z O IC Paleoproterozoic cratons: m o b ile b e lts: M O B IL E B E LT S A M Z A m az o n ia n 1 Espinhaco-Pram inim 撞翻享狱李 r, t别om l oi}a ca etionary t e lts B D K B undelkhand la M ayom be 1 b A ra x a 髯桑翰鬓 ,n t怕 C O川 in en t创 b e 招 C N G Congo X 0i-7 D Dharw ar 1 C S a o R o c a 必E A E ast A ntarc tic a ld Tijucas G A Gaw ler 2 K ib ara n - lru m id e E S N E ast Sah ara- N ile 3 M ozam bique KG Kalahari-Grunehogna 4 N am aqua-Natal- L A U L a u ren tia F a lk la n d s/M alv ina s IVID M adagascar-Dharw ar 5 E G h ats- C en tra l NA N orth Australian India-M aghalaya N C N o rth C hina 6 A ra v a lli R R o c k all 7 A lbany-Frazer 协R LP Rio de la Plata 8 Paterson-M usgrove S S a lv ad o r 9 N E A u stra lia S C South C hina 10 Y angtze- S F Sao Francisco 1 1 G re n v ille S 旧 1 2 S u n sa s W A W est A ustralian W A F W est A frican 13 A guapei 14 Sveco-N orwegian- G re en lan d - S v a rlb a rd p o sitio n 以 R LP u nc e rtm n 15 K uanping

F igure 2 Th e R odinia sup ercontinent assem bled at c. 1000 M a.

m ian tef anes to the south-w est of the M argin of B altica- the T eis- w as coined (U nrug, 1992), is younger and belongs entirely to the seyre-T ornquist line of w ere part of the A valonian-C ado- G ondw analand cycle. T he M ozam bique belt w as probably prolong- m ian province ot G ondw analand (Figure 1). C entral and Eastern ing into the circum -E ast A ntarctica m obile belt, and Sri L anka w as A sia terranes w ere part of the C im m erian province of G ondw ana- located at the juncture of the tw o (Y oshida, 1994; 1995). land (K atz, 1993; M etcalfe, 1993; 1994). T he intracontinental K ibaran-Irum ide belts of easte r n equator- W est G ondw analand included the A r c hean-Paleoproterozoic ial A frica originated during an extensional event betw een 1350 and East Sahara-N ile, W est A frican, A m azonian, and R io de la Plata 1180 M a and w ere deform ed in a com pressional event ending at cratons, and possibly a separate cratonic block now in the basem ent 1100 M a (Klerkx, 1992). They are linked by transcontinental shear of the Parana basin ot S outh A m erica. T hese cratons are sutured by zones to the collisional m obile belts surrounding the K alahari craton, m obile belts form ed during the N eoproterozoic Pan A frican-B rasil- and are regarded as im pactogens created by continental collisions in iano orogem es. Som e m obile belts contain oceanic sequences and the N am aqua and M ozam bique belts. sutures m arked by ophiolites and gravity anom alies. A system of basins filled w ith se d i m entary and volcanic rocks of M esoproterozoic age (review in T rom pette, 1994), deform ed in the N eoproterozoic, is present on both sides of the southern A tlantic. R odinia configuration and breakup T he R ibeira m obile belt, and part of the D om Feliciano m obile belt of B razil and U ruguay, and the M ayom be unit of the W est C ongo belt of Equatorial A frica contain the m etam orphosed sedim entary fill The reconstruction of R odinia at the end of M esoproterozoic (Figure o f these b asins an d reactivated ba sem ent inliers. T h ese b asin s are 2) is based upon the SW E A T hypothesis (M oores, 199 1; D alziel, interpreted as M esoproterozoic aulacogens deform ed in the N eopro- 1991). Sadow ski and Bettencourt, (1996) have described details of terozoic. T heir original position in R odinia is uncertain, but they the of the Laurentian and A m azonia cratons lying in the appear to be linked to the C ongo craton. G renville-Sunsas orogen. In A ustralia A rchean-Paleoproterozoic cratons w ere first am algam ated into a configuration sim ilar to the present one in the interval 1300- 1000 M a (M yers et al., 1994; Shaw et al., 1994). The A lbany-Fraser orogen contains the m ajor A us- E arly events in the G ondw analand cycle tralia-A ntarctica suture, and the associated continental-scale shear zone extends into the B unger H ills of A ntarctica, and into M egha- N eoproterozoic events predating the breakup of R odinia (Figure 3) laya in India (H arlis, 1994; 1995). T he suture linking A ntarctica to are considered early events in the G ondw analand cycle. W idespread Ind ia lies in the E astern G h ats-c ircu rn E ast A ntarctic m ob ile b elt early N eoproterozoic extension, rifting and intracontinental and (Y oshida, 1995). T he Indian and A ustralian m obile belts have exten- oceanic basin form ation overlapped in tim e w ith post-tectonic m ag- sive foreland basins preserved (e. g. M yers, 1990; W etherley, et al., m atism dated at 850 M a (G roenew ald, 1993; Pinna, et al., 1993) 1994). L i et al. (1994) defined the position of N orth C hina and South shearing and tectonic escape events follow ing R odm ia assem bly . C h ina c rato ns in R o d m ia. In A ustralia the form ation of a rift and sag basin in the A delaid e T he N am aqua-N atal- M a udheim m obile belt borders the K ala- 'geosyncline' started at 830 M a or earlier (Pow ell et al., 1994, M yers hari-G runehogna craton of south A frica and eastern A ntarctica et al,1994). C orrelative sedim ents are present in the Savory-O fi cer (G roenew ald et al., 199 1; G roenew ald, 1993) and from D ronning and A m adeus-N galia basins (Pow ell et al., 1995). E arly events are M aud L and joins the circum -E ast A ntarctica belt. A suture zone is w idespread in the A N E K T orogen: bim odal m agm atism dated at 880 interpreted from geophysical data in the N am aqua-N atal belt at M a in th e A rabian sh ield an d 8 70 - 840 M a in the N ub ian sh ield is 1100- 1000 M a (G resse, in Pow ell, 1993). T he M ozam bique belt in interpreted as a rift ing event, and ophiolite em placem ent is dated at M ozam bique and southern Tanzania is a late orogen in the R odinia 880-690 M a (S tem , 1994). Farther south in K enya, the sedim entary assem bly in w hich dated at 950 M a (Pinna et phase of the m obile belt evolution is placed at 1200-820 M a and al., 1993) w as preceded by early m etam orphic events beginning at m igm atitisation, start of collision, and ophiolite em placem ent at 830 about 1200 M a (G roenew ald, et al., 1991; G roenew ald, 1993). T he M a (M osley, 1993). entirely N eoproterozoic belt farther north in E ast A frica, for w hich Several early nft in g events are know n in the deform ed corridor the acronym A N E K T (A rabia-N ubia-Ethiopia-K enya-T anzania) betw een the K alahari and the C ongo cratons of southern A frica. Sed-

肠,isodes, VoL 19, nos. I &2 1 4

Te rra n es In the 月阳 七rr 介 N u 七J舀n sh ield P , Tarra n es in th e 知 口门9

}ss?州a- 钦

犷一撇 气尧琴‘ 界 ‘ 、 an d E S N c ra ton s 、a nd of G oias a nd

--w 、 a re u nce rta in .T he p os itio ns o f 如W C口姗 助..Opm 抽m 盈。X n d A ra bia n -N ub ia n sn ie las a 旧 riot Sul那ow s quantitatively

BA SINS (opening age) M O B ILE B ELT S (deform atio n age) P R O C E S S E S A G E 咖 7 (成】V 日 瑕 东统 A ul ac cg 即 蛟 煞 熟 撼 Intramntinantal 荟夔葵兹 Dr"Wp 碉-枷 黔涣歌孤 咖 Passhe margin 111111川 M d . 习吕日 究 Cdblnal 琳丢端一 、‘, -,扒 I弧洲〕M 日 蒙笔蒸霎攀

A}'- 斤倒习。 奕奖1 B reakup fi n. C-Doo M g.-ft a n, AW IR Subdwrfion 峨 一一 ,仪幻 一翎 M 日

F igure 3 E arly N eop roterozoic events (1000-700 M a) events in R odinia.

itnentary basins of the G hanzi rift, and the R ufunsa and Fingoe B razil (V an Schm us, et al., 199 1; B rito N eves et al., 1994) C ontinu- basins fortned at c. 1100 M a, younging to the north-w est (U nrug, ity of structures across the A tlantic and data from N igeria and north- 1995). T he R ufunsa m etasedim entary succession is intruded by ern C am eroon w here rifting is dated at 800 M a suggest this rift ing granite and rhyolite dated at 944 M a. In the next rifting event, event w as extensive and long lasting. bim odal volcam sm m arked the opening of the sedim entary basin of Juvenile crust accretion in early e ve nts of the G ondw analand th e intracon tinen ta l Z am be zi b elt at 8 80 M a. T he Z am b ezi be lt w as cycle has been recognised in South A m erica. E arly N eoproterozoic transpressionally deform ed at 820 M a (B arton et a]., 1983; W ilson et age w as determ ined for the w estern part of the crystalline G oias m as- al., 1993). T he L utio belt in the M ozam bique orogen is believed to sif, previously regarded as A rchean. Protoliths of orthogneisses crys- be a prolongation of the Z am bezi belt (Pinna et al., 1993). Trans- tallised at 899 M a and m etavoleanic rocks yielded ages of 929-877 M a and 764 M a (Pim entel and Fuck, 1992). A t the eastern m argin of pression in the north-eastern part of the m obile belt betw een the K alahari and C ongo cratons had a rotational kinem atic com ponent, the R io de ]a Plata craton the polyphase m agm atic activity in the as at the sam e tim e the T sum is rift opened farther to the south-w est Pelotas com posite batholith started w ith a m agm atic arc at 850-830 in the future D am ara belt. T his rift ing event w as abortive, and the M a (T rom pette, 1994) .In the R ossorogen of East A ntarctica rifting ev olutio n o f the D am ara b asin d id no t start u n til the N o sib rift started at c. 750 M a (Stum p, 1995). The rift evolved into a passive form ed at 770 M a (U nrug, 1995). In southern A frica, a rifting event m argin sequence, in w hich shallow m arine carbonates and deeper- w ater turbidites w ere deposited. opened the basin of the Saldania belt at c. 900-800 M a (G resse, in Powell, 1993). T he basin o f t he K atangan Supergroup in the L ufilian fold belt P a n A frica n - B ra silia n o ev en ts opened probably in the latest M esoproterozoic. T he elastic and shal- low m arine carbonates of the low er part of the succession are over- lain by conglom erates and basalt lava flow s and intruded by basic T he Pan A frican-B rasiliano that shaped the G ondw analand stocks and sills of the L ow er K undelungu group (U nrug, 1994). T he supercontinent accretion is redefined here: it began at 750-730 M a Low er K undelungu m arks a second rift ing episode, w idespread in w ith the reorganisation of crustal plate m otions follow ing the breakup central A frica from sou th ern K asai to th e T an zan ia . B asalts of R o d im a. T he b etter kn ow n P an A frican- B rasiliano m ob ile belts o f are dated at several locations at 950-800 M a. This rifting event w estern G ondw analand contain m agm atic arcs and lithotectonic ter- form ed the K undelungu and B ukoban aulacogens and a num ber of ranes that originated during early N eoproterozoic events. H ow ever, sm aller ba sin s. the large cratons w ere individualised after R odinia breakup, and, w ith In South A m e rica, w idespread rift ing at c. 1000 M a has been the exception of an early collisional event in the A N EK T belt, all cra- recoRnised in the B orborem a tectonic province of north-eastern ton collisions postdate the breakup of R odinia (Figure 4)

M a rch & J une 1 996 1 5

F igure 4 The Pan A fi can- B rasiliano orogeny and the assem bly of G ondwanaland, 72 0 - 5 5 0 M a .

T err an es in the Tuareg and A N u b ia n sh ield s : 1 Egere-A 2 Isk el 3 In T eidii 4 A ouzegL 5 A sso d e- 6 Sero uen, 7 In O um 8 K idal 9 Tilernsi 11 M idyan 12 H ijaz-G 13 Bayuda 14 H aya 15 A sir 1 6 A fi f 17 Ar R ayn

SB Senegal block N B N igeria-Borborerna BASINS (opening age) M O B ILE B E LT S (deform ation ag e) P R P a ran a b lo ck

B AS IN S I 邻} Ift a ga) M O BIL E B ELT S I } - a ge )

肠 n 拔之共扮 划狱‘旧. zX1W - - 抉澎 P ..曲. ..叫n 澄N - IRPA I. 八‘加.n 曰 口n 黑 山 朋k 卯 助阅 灿,已., 脚 ,口旧咖.凡 蜜组鱿

P R O C E S S E S A G E

声G E

压“南叩 峨目渗 。月缺内明 峭《 黑嚣尝黑 岛山改.‘拍 闷 雀 与卜 9 . fo .. 一

T h e A N E K T b elt zone s an d con tin ental co llisio n w ith the W e st A frican crato n are dated at 640-580 M a (B lack et al., 1994). In the A nti A tlas in the In the A NEKT belt, the early Gondwanaland events pass into the north-eastem com er of the W est A frican craton the em placem ent of m ain structural and m etam orphic evolution in the 730-630 M a inter- the B ou A zzer is som ew hat older: the ophiolite dated at c. 790 M a val (M osley, 1993). G ranulite facies m etam orphism is dated at 715- and the m etam orphism related to the obduction w as dated at 685 M a. 630 M a in T anzania and 740-71 0 M a in Sudan. Final suturing of the A younger deform ation phase is placed at 620-615 M a (V illeneuve, com posite superterrane of the A rabian-N ubian shield w as com - et al., 1993). pleted at 680-640 M a. A num ber of ophiolite belts outline Tw o sh e a r ing events are distinguished: the older one at boundaries in the A N E K T belt. T he oldest ophiolites em placed prior 645-580 M a produced the dextral R aghane (8'30') shear zone; the to R odiniab reakup are know n in the A rabian shield. D evelopm ent of younger produced sinistral shear zones cutting all previous terranes. large shear zones lasted from 660 M a to 530 M a, indicating a long The age of the latter event is estim ated at 525 M a (Li6geois et al., period of convergence of East G ondw analand and the C ongo craton. 1994). T he T anganyika shield of the C ongo craton acted as a rigid indentor causing tectonic escape directed m ainly to the north (Stem , 1994). T h e D ah om eid e b elt Y ounger granulites in the A N E K T belt, dated at 545 M a, are sim ilar in age to granulites of M adagascar and southern India. The southern prolongation of the trans-Saharan belt- the D abom eide belt- is th ru st o ver the fo re lan d V o lta basin th at sits o n the eastern T h e tra n s-S a h a ra n b elt m argin of the W est A frican craton. The basin fill includes a passive m argin sequence developed during the 700-600 M a interval, facing T he trans-Saharan m obile belt exposed in the T uareg shield of w est- an ocean to the east. V arious interpretations of the D ahom eide belt ern A frica is interpreted as a collage of lithotectonic terranes w ith a have been proposed. C lassically regarded as m arking the w estern com plex polyphase deform ation history. B asem ent blocks, som e m argin of the W est A frican zone of m icrocontinent aggregation w ith passive m argin sedim entary sequences, m agm atic arcs, and (A ttoh et aL, 1991) and a suture (A ttoh and D allm eyer, 1992), it w as accretionary w edge terranes, som e w ith possible ophiolite rem nants, attributed recently to intracontinental rifting (C astaing et al., 1994 )· are distinguished (B lack et al., 1994). E arly collision of terranes w ith the w estern m argin oft he East Sahara craton, deform ation and w est- T h e M a u retan id es an d B assa rid es b elts dipping -related m agm atism recorded in the A ir and east- ern H oggar at 750-660 M a w as follow ed by deposition of the early O n the w estern side of the W est A frican crato n the M auretanide an d Pan A frican Proche T 6n6r6 m olasse (L i6geois et al., 1994). T errane B assaride belts are interpreted as having evolved from a narrow collisions in w estern H oggar and A drar des Iforas w ere associated- oceanic basin of R ed Sea type w hich opened at c. 700 M a and w ith late Pan A frican m agm atism related to east-dipping subduction deform ed at c. 650 M a (V illeneuve et al., 1993).

Ep isodes, VoL 19, nos. I & 2 1 6

T he B orborem a tectonic province 1990). A structurally higher unit is com posed of syntectonic m igm atites and gneissic granites intruded by syntectonic foliated In South A m erica, the prolongation of the 4'50' shear zone of the granites. Eclogite-grade m atic m etavolcanic rocks m ay represent a Tuareg shield is placed in the Sobral shear zone (C aby, 1990). In the narrow slice of oceanic crust, and associated gravim etric anom alies B orborem a tectonic province of B razil, east of the trans- are interpreted as m arking a suture at the south-eastern front of the Saharan-M edio C oreau belt (T rom pette, 1994) a netw ork of Pan- m igm atite and gneiss unit. The structure of the m obile belt is dom i- A frican shear zones and m obile belts separate sm all units of A rchean nated by sub-m eridional trends, attributed to east-west com pression and Paleoproterozoic basem ent and basins filled w ith M esoprotero- in a w ide zone along the northern m argin of the C ongo craton (C or- zoic m etasedim ents. N eoproterozoic m agm atism is w idespread. naccia et al., 1990 N A N C Y ). R ift-related volcano-sedim entary sequences in the m obile belts are Farther to the north-eas t in Tchad, m igm atite gneisses w ith dated at c. 1000 M a (V an Schm us, et al., 1991; B rito N eves et al., granite intrusions are tentatively assigned a N eoproterozoic age 1994). This is regarded as an agglom eration of terranes (K usnir, 1993). T he N N E trend off oliation in the m igm atites is sim - including older basem ent blocks, m agm atic arcs, oceanic sequences ilat to the m ain structural trends of the O ubanguide belt. C urrent and passive m argin basins in the north-east B razil-N igeria- interpretations consider the N igeria-O ubanguides as a collisional C am eroon province of the Pan A frican-B rasiliano orogen. The geo- orogen involving several lithotectonic terranes and the closure of a chronology rem ains insufficiently know n, and the interpretation of narrow ocean. T he Tchad region m ay belong here as w ell. older R b-Sr dates is difi cult. T he shear zone contained betw een the P ato s an d P ernam b uco lineam en t of n orth-ea st B razil can b e traced T h e B r asilia b elt into C am eroon (T rom pette, 1994). In the B rasilia belt, the early N eoproterozoic m agm atic arc produced T h e Sergipe-O ubanguide belt juvenile crust in the G oias m assif. O ceanic m etasedim entary sequences w ere deposited before c. 640 M a, and m etam orph ism and T he soutb-vergent, east-w est-trending O ubanguide-Serg ipano deform ation peaked in the 640-600 M a interval m arking collision of m obile belt correlated from South A m erica to A frica is thrust over the A m azo n ian and S ao F ra ncisco craton s. F orm ation of east-v er- the northern m argin of the C ongo-Salvador craton. In , in the gent thrust sheets and intrusion of rare syntectonic granites is dated Sergipano belt, a south-to-north transition from passive m argin car- at c . 60 0 M a. bonates to greyw acke-dom inated sedim entary protoliths is recog- nised. H igher-grade m etasedim ents in the central part of the belt T he w est C ongo-A ra}uai belts and th e M antiqu eira contain a m afic-ultram afic com plex. The age of m etam orphism and p rov in ce syntectonic grannoids is estim ated as 660 M a. In A frica, the O ubaD- guide belt evolved from several rift basins form ed during an early- T he W est C ongo and A raquai m obile belts, the Param irim aulaco- N eoproterozoic extensional event through a passive m argin in the gen, and the M antiqueira tectonic province of B razil m obile belt south to a turbidite dom inated sequence in the central part of the belt. form a vast region straddling the southern A tlantic, in w h ich pre- The m etam orphic grade increases to the north, aw ay from the m argin M esoproterozoic basem ent terranes, M esoproterozoic aulacogens of the C ongo craton. A granulite-grade m etam orphic event dated at and N eoproterozoic intracontinental basins w ere deform ed in the c. 650-640 M a w as follow ed by the m ain deform ation phase and Pan A frican-B rasiliano orogeny. Lithological correlations are pro- em placem ent of a regionally extensive basic to interm ediate plutonic vided by glaciogenic sedim ents. The M esoproterozoic m etasedi- suite at c. 630 M a. The plutonic suite has calc-alkaline afi nity and is m ents and associated m afic or bim odal igneous rocks include the believed to represent N eoproterozoic juvenile crust (T oteu et al., M ayom be group of the W est C ongo belt, the E spinhaqo group of the

C raton s 薰蘸黝 T1aconian-Famatinian collisional orogen 口 之 Earaguay-Cor5的a beft G ranites and Syenites; J 竺a m p ea n exu ll三te rra n几 4 v u n co viscan a-t asie rn r am pe ana s D en 困 P reco rd ille ra te rran e 万 Pegm atite fields 翼薰瓢、 ‘ 7 馨 龚琴然浦 扭fia te rran e B M esoproterozoic m obile belts Appalachians 鬓 瓣聋摹 瞬械 Neoproterozoic 然蜒 io b ile b e lts 纂 琪券建 犷掣糟犯一_N 搞 鬃 翼

-I\\eR}0\0 '\1 雍幸 馨 抓黯 沙墓雄i 探雌斌纂 红翼 笋灰梦尹吟葬 ,,}- 4 馋 瓢 麟 黔 狱 粤 卜PO S 不 A N D A N O R O G E N IC M A G M A T IS M IN G O N D W A N A LA N D }川 .}Lachlan-Thom son passive m argin P 崔 H im alaya m agm atic event

38882 Ross-Delam erian m agm atic arc X\ Il} N { A va lo n ia n te rra n e s o f N o rth A m e ric a and Cadom ian terranes of Europe

F igure 5 C am brian-O rdovician events in G ondw analand, 560-440 M a.

M a rch & J un e 19 96 /7

Sao Francisco craton and the A ra}Llai hell, and the Val-IOLIS M ills Of 1992), and dcl-orm alion in the north ol'the I-Lifilian bell is interpreted the M anticlucira prm incc. O thcr 山all tile clatollic CoNer Ullit', C.L. ts I'allin-1 in the 670 (,{)‘)M a inter%al the W est C onoo oroup hasin and tile San-lia atilacoi-'en oil the T he G aricp licit 01'COaSlal SOLI(h 一 }% , 'Icin A l'rica contaill",:、rill A trican side and the B anibui G rm lp ill South A nicrica, the only N co- sCCILIC11CC arld :。Com posite tcrrane ol-occanic ,一、)cLs holll thl-LIS1 on the proicrozoic hasin of tlic m obile belt is M aCaUbas group hasin inthe K a lah ari crato ll. 'I'lle S al(jariia m ob ile be ll alo m -, the w estern a nd A ra}Llai belt ill lil-a/il. It is fillcd w ith 111911一91:LoIc i ll etasCclillients SO LIthC H ) m ar,_,in o l'the K a laha ri cral(川 co ntain s a vo lca no-scd i川e ll- inici-picted to he orioIinall} som e 1.} kill thick (T rorripctte. 1994).The tary sequence delorm cd at 650 M a. It contains inalic volcanic lock- W est C oll-o arld 八ra}:Uai he II , ha% C a Cli\ Cl-I- 'e ll( laI I Stl-LICI UrC, t hC ,,tentatively interprew d as possible ophio litic rellinalits. Syn- to late- w est C ongo belt ha%ing been fit:一[ist castw a,一。I over tile C origocratoll tectollic ,"r anit川d、川trudcd the bell in the 6 10--520 M a interval (H ;il- ind the A ra}uai belt w cstvvard over the S ao Francisco cralon. M eta- hich. 1991 G rcssc, 1990 ) m orphism alld k-111COL11, aCliviiN, arc dated in the W est C on,-o-A ra}Llai belt at 63()一000 M a. In Current interpretations. the cast w est crustal I’h e younger generation of m obile belts in W est shortcnirw ill the W est C onto and A ra}riai bells term inating against G o nd w a na la n d COIllilILIO LIS CratO lliC hasC irie nt to the no rth , is acco m m odated I)v N eoprotero/oic deform ation in the Param irm l aulacopcli that scpa T he lic-irm ill" ol,cw hilion of all m obile belts of'w estern G ondw a- rate,, the Sao Fiancisco cralon seim i 、/,;(lo tioril the C om-,()-Sal- 11aland CicsCrilled ahove can be traced to the carly N coprotcio/oic \ad o r cralo n (U hic in , ct al., 199 0, C he iriale et a l., 19 93 ). period A CrIlstal extension pre(latinp, the hicak il) of' R odinia. File M alltICILICila 1CC10111C Pl-OVillCC COlltaillS tile C Uh a ( n -A lcm I rom pettc (1994) (11-c\v allentioll to :,,;econd _,ciicration ol' m obile bell,, in W est G ondw analand ():一:Lillatilw, from ril-ts Younger thall Paraiba m eoashear zone ill w hiCh VCl-liCNI trall,CL11-1-Cilt taUlt's PNSS. 10 0 50 M a and (jejo l-Illed at 之1 1)O LII 55 0 M a. T hese bells 川ClUde the tile n orth一w est, in to llat th l-L[St Shee t、 -1 Ile tratISCH I-re llt fal-IltS. M O StIV Rolkelidc belt of W estern A lticLt and the A ra,,Llaia-PaFa(,LlaV-(、O r- dexii-al, ,cpaiaw basem ent lior.}ts and M csoprolcrozoic hasins. W i山 d o ha hells O f'SO LIth A m e rica . 'I’l ie n atu re 、)}th e be lts is how ever clit- tile exception of sillall 111olasse hasins there are no N eoprotcro/oic lerent: the Rokelide belt is attributed to dextral shcarinL, betw een the rocks ill tile M aIlliCILICira proviricc. The defo rm ation is B rasiliallo. A m azonia and the W est A frican cralon (V il]CIICLIVC Cl al., 1993). T he w ith tw o pha,}cs at 7-50-660 M a and }50 M a ()ado" ,.ki ct al.1994 ) nature of the A ral-Ulaid belt is unclear but current interpretation leans A t it', SOL1111CI-11 crid, file, R iheira belt passes v\cst oftlic Louis A lvc,} to vvard s a B rasilian o he lt 川vo lvin,}i occa nic Cru st and ru ctascd im en - cratonic basem ent block that links pl-CSLim ably w ith the Rio de la tal-V SCqL]CIICCS. '['he l'al-aLILlay--C ordoba belt includes :、Craton Illar- I'lala cralon. A hunclant (,ranitoid iii(rL[SiOll, alO1W tile A ilaillic Lin hasin w ith polvphasc deform ation, ituruded by 550-50()一NIZI-old co)astal /onc o l' the R ihcira and D om Feliciano hells, accom panicd 1ale tectonic Lralli(es 0 rom pette, 1994). hy I,i ic i sscs and charnokilc}., CO1lStilUtC tile Rio D OCC Illiw-illatiC ::,。 'l’lic above -eneralised descriptio n o f W est G ondw analand cla tc d a t 5 5 ()-5 0 0 M a . m obile hells coniraclicts the concclpt of 'collision’ of W est G ondw a- I'lic D o m 1,c licia n o b e lt extend s its lar as 山c Castel it "ide of, tile na land w till F ast G o nd w an alan d . A n 川n he r of te rrancs a nd 川terve ll- R io dc la Plata Craton. The W estC1111110st Ullit, CHICI-I-1 11 1I1 1'10111 LIFICICI ing occall hasins tclcscopcd betw een the m ajor cratons dUrill(II the tile Co ve r o f, file P aralla h asill} is the V illa N o \ a h ell. It IFICILK IC S a Fill assem bly of \N est G ond\&analand but this process "IaS COInIFILIOUS to PaSSIVC 111al-111111 SC(ILICIICC 一the V acacai (also called H avalcia) and invok ed a M linbei of collisional c),cius during a long period of SLlpcroIr O Ll P,:1 11d tile C alllhai COlllPICX COIlSiStitIL-'(、!lilielssic 1I1,一“11111c Convel gence, I athel Illan one m ajor }:ollisioll betw een L ist and W est a nd m alic to ultrain atic rock s (F erriand c/ et a l., 199 21). I'lle k itte l (io lld w a lla la n d CO111ai11S _jL1%'C11ilC CrUst form cd at 750-700 M :曰11 a 111a"Illatic are. (Bahinski ci al.1996), Farthcr cast, M csop,一‘)tclozoic 111ctascdi- N eop roterozoic oceans m ents of、 the T i1jucas bell, scparate 山c V illa N ova bell front the 11clotas hatholith form ed in an early N eop;一()locro/oic polyphase T hree m ajoi N eop;一、)tcrozoic occalls Closcd durillI" t ile assclilhl}- of iliag111allc arc 日I w hiCh SUM LIC11011一relatcd 111agInatic activo hCoall G ondw analand. Firstl}, rocks 101-111C(I by aillahlaM atiOll OI'jL1VCnlIe at 850-830 M a. fo)llo),ked by anatectic oranitoids at 750 M a. Y OU11"Cl 111:19111:ltlc :、,℃、and ()山er tell-alies (Stocscrct al., 199 1)ill the A N E KT (,ranilOiCIS iIIII-LICIed at }50-500 M a are assioned to the R io D occ O ccall are exposed ill tile 八rahian-N Lihian shield. ]it 山e cast this m a,_,m atic arc. A L ate N coproterozoic m olasse hasin defo rm cd at ocean w as bordered by the Fast G ondw ana . Ill file w est。 550 -500 M a sits on top ol'the V illa N o vit bell. rellillailt()}、a passive m an,in to the Fast Sahara- N ile Cratoll is pre- 、。:ved (Stel it ct、d ., I 993),hLit the N ile cratori appears to be distinctly I、一:toritented (Scharidelm eici, 199 3). T he Pharusiari occan nam ed T he D am ara, G ariep , and Salclania m obile belts altertlic accretionary W CLI1'C C&,l of thc W cst A lt-ican Craton 山。see-

T h e C \,o lLl(iO t) O f th e D a m a ra m o b ile h e lls sta rte d \A, ill) th e lo rm a tio n ond large occ}jn ol- W est G Ondw ariaLlIld, NA as situated aloll"I tile cast- ci it m argins of' the W est A frican cratons. Its closure I-ClAilted Ill tile o fthe N osib volcan()一sedim entary, seL]UCnce deposited in a rill hasin fo rm a tion ()}、the T ran s-S ah aran m ob ile h ells o l'W est M ric a and the datcd at 770 M a. I lie post-rift m assive m argin of the C ongo cratoll M C(IiO C OI-CA l CI、一(m 1pet比 1994) m obile belts Of SOLIth A m erica. cle}一eloped in the 7 10-000 M a interval and w as lollow ed 1)), the foi T he P 11,1111SIall OCCall CO U ld e xtend farthei SO LIth in to the o cean fro m in ation of' a continental m ar9川 ITIZI9川:Itic arc w ith calc-alkal日。c w hich the B rasilia belt w as form ed M w een (he eastern m anIin of the inirusives. arnphiholitc pradc m cianiorphism and polyphase defor- A m azonian crat()门:ind the w estcrii m ar-in of the Sao Francisco cra- inaiion in the 66()一590 M a inict-val ended by continental collision. toll hLlt tile possible jL[11(:IiOll arca is concealed by the Phanerozoic Farthci to the south-east is all accretionary w edge com plex " ith Parnaiba. A d il'I'crence ol' opinion persists over tile question of' the hiIgh-pressure m etam orphism . Sedim entation 。);]the passive inarloni intcrvcnino N iLcria--H orhorem a province, \,\here continental rifting o f the K ala hari craton lasted till c. 57 0 M a. R em na nts ol a lo rela nd and shear /one developm ent is hclicvcd by som e aLlthors to have thrust and fold belt, cniplaced over the N arna forcland hasin in 山e played a dom inant role in the rencti%ation of older sirlActures' (Jardim K alahari Craton, f0l"Ill the SOLItherninost part of the D am ara belt. dc Sa et ill., 1990} B rito N eves 1994 } C astain,I ct at., 1994 ), w hile P o st-c o n tin e n ta l c o llis io n sh e a r / o n e s d iv id e d th e ru o h ile b e lt in to a others re}I,ard occan CIOSLll-C alld all1algalflatiOll tu ranes as prilicipal num ber a tcrrancs (G resse et al., 1994 ). C urrent interpretations based geodynarilic events (L iegeois ct al., 1994 ).『I ’hc 0 uham uidc belt is oil sedinientoloLical studies (H enry et al., 1990: Stanistrect et al., possibly tile SOL101CI-11 part of' 11harusian occan The third- thc 199 1; K ukla and Stanisti-cet, 199 1)view the D am ara belt as evolving A claniastor O ccan-- Ia} betw een the w estern Part of’ the C ongo cra- Ir()川all Occa川c ba%川.possibly ot'lim ited w idth. Ill this context it is to n , the K alaha ri crato n o f' E a st G o nd w an a and the R io d e la P lata possihle that the A ngola shield w as independent of the rest of the craton of sou山A m erica. T he D am ara and G ariep tiiohilc belts. and C onIoo c ralon, and the W est C onoIo belt links w ith the Lutilian belt the D om Feliciano m obile bell ol'B rasiliam id U I-LIgLI:Iy (f,crnandez et L11)(If tile YOLIII,I,cr covcr of' the Beret,, hasin. Peak m etairiorphi sill川 al一1992: Bahinski ct al一,199(1) Contain ophiolites and IllaI-m alic arcs the central part of the LAtIlliall belt is dafed at 700 M a (C ost ct al- fo rm e d in th is o cc a n

均 n so dc.}, V o l. 11),,,。,‘、.I & 2 1 8

Sh ea r zo n es R e f e re n c e s

A ll internal m obile belts suturing W est G ondw analand contain large A ttoh, K , H awkins, G , and Bow ring S A , 1991, U -Ph zircon al-es front the shear zones form ed during late stages of craton convergence Pan A frican D ahonreide orogen, W est A frica: Fos. T ransactions Arneri- Im proved intercontinental correlation of the shear zones (e.g. Sri- can G eophysical U nion. Spring M Cetiru SUPPIenicn( v. 72 (abstract). navasan, 1994) indicate tire im portance of tectonic escape processes A ttoh, K, and D allineyer R D , 1992, 4 1) Ar/3"Ai- A ge spectra of hotriblendes and adjustm ent of young hot crust betw een the coider rigid cratons fro rn th e P a n A fric an D a h o n rc id e su ture z o n e . W e st A fric a : 1}o s, T ra n s- (B lack and Li6geois, 1993). It is notew orthy that the C ongo craton is actions A m erican Gcophysical U nion, Spring M eetiuL} Supplem ent v. 73, p.366 (abstract) surrounded by shear zones produced by a generalised cast-w est B a b in sk i, M } C h e rn a le f% Jr. H artin a n n , L A , V an S c h in u s, W R . an d d a S ilva , com pression- and appears to forin the keystone of the W est G on- L C , 1966, Juvenile accretion at 750-700 M a in so uthern B razil: G col- dw analand assem bly. ogy, v. 24, pp.439-442 Barren, C, E} ans, J A , C arney, J N , Crow , M J. and Siniango, S. 1993, Geo- logical and structural frarriew orl, of、 the Zarribezi Belt, northeastein Zinr- L ate- to postorogenic events in babwe, M Tindla), R H, U nrug, R . B anks, M R , and Vecvers. J J cds., G ondw ana Fight: A ssernbly . evolution and dispersaL A A Balkerna. Rot- G o n d w a n a la n d terclarn, pp 55-68 B lack, R , and Li}geojs, j P, 1993, Cratons, m obile belts, alkaline rocks and W idespread late- and postorogenic inagm atisin, shearing and m ajor continental lithosphcric nrantle: the Pan A hican testurronyA ournal oft he G eological Societv, v. 150, pp.89-98. uplift leading to deep exhum ation of the m obile belts are salient fea- B lack, R, Latouclic, L, Lielgeois, J P, C aby, R , and Bertiand, J M , 1994, Pan- tures of G ondw analand assem bly. generally attributed to a m ajor A frican displaced terranes in the Tuareg shield (central }ahara). G eology therm al event lasling into the C anibrian-O rdovician. I’w o m odels }% 22, pp.64 卜044. have been proposed to account for this event: In the A ntarctic shield, Brito Ncves, B B, 1990, Proterozoic passive continental inargin ot w hich apparently w as stable from the M esoproterozoic consolida- Brazil-A frica: A bstracts l5th Colloque de Geologic A fiicainc, Syropo- tion of Rodinia, underplatimL-,1 by basaltic rnagm a derived from the siurn S-5: C ontinuity ofrna}jor structural features trorn A frica to adjacent asthenosphere, and resulting heat advection. has been postulated ex-G ondw ana , N ancy. France, p. 168 (StOve and Sandiford, 1993). In northern A frica, w here N eoprotero- C aby. R, 1990. Tile I一;ite Proterozoic South A tlantic tit: PCt1'OStR1CtL1ral cvi- zoic m obile belts reach great w idth in the T uareg and deuce troin southwest Nigeria and northeast B razil: A bstracts l5th C ol- loque de C eolopie A fricaine, Syrnposiurn S-5: COrniflUity 01 M ajor StrLIC- A rabian-N ubian shields and the intervening East Saharan-N de cra- tural features from A frica to adjacent ex-G ondw ana continents, Nancy ton w as partly dism em bered during the Pan A frican orogeny, the France p. 169. late-to postorogerfic effects are attributed to lithospheric m antle C hern ale, F Jr ,A lkinim , F F, and FInd o 1, 1993. Late P roterozo ic tccton ism delam ination and thinning or elim ination of the lithospheric m echan- in the interior ot the Sao Francisco craton, iii Findlay, R H, U ntug. R real boundary layer follow ing collision of lithosphcric plates, and Ranks, M R , and V ecvcrs. J J eds., G ondw ana Fighti A ssem bly, CVOILI- direct coinact 01' Crust w ith upw elling asthcno印here. T he rapid tion and dispersal: A A Balkerna, Rotterdam , pp.29-4-1 change of synorog enic calc-alkalm e inagnialism to postorogenic Cornaccia. M . G iorgi, I,Vicat, J P, B londin, P. Bahct一N . and M inot一J B, alkaline w ould be explained by change from a subdLiCtiOll-related 1990. D onn6s nouvelle.s sur ]a tcctogen6se parm tricanic en Republique m agina source to a less depleted asthenospheric source (B lack and Centrafricairic: A bstracts 1.5th C ollocille de G eologic Atricainc, N ancy, L i}geois, 1993). Isotopic studies indicate large-scale addition of France, p.254. C osi, M , D e B o njs, A , G osso, G , H unzjkcj-, J. M artino tti (〕,M olatto. S , supergene w ater as an im portant factor in Pan A frican radiornetric R obert, J 11, and R uhlm an, F , 1992 , I-ate Proterozo ic thrUSt tecton ics. rejuvenation of basernent rocks of G ondw analai记(L onginelli et a]. high-pressure m etam orphism and uranium m inerali/ation in the Dom es 199 4 ) atea, Lutilian A rc, northw estern Zam bia. Precarnhrian Research v. 58. pp. Y o u n g9 radiom etric ages. form ation of granulites. and m yloniti- 2 15 - 2 4 0 sation (550-450 M a) extending from the East A frican A N E K T belt Dalla Saida, f.Varcla, R. and C ingolani. C 一1993a, Sohrcla collision de Lau- into M adagascar, Southern India. Sri L anka and E ast A ntarctica rentia-Suclaincrica y el orogeno Farnatiniano: X II Congreso Geologico w ere interpreted as indicating a Possible SLOUre zone betw een E ast A rgentino y 11 C 011111-eSO de 1-.XPIOFacion de H idrocarbUrros, A ctas, t- 111, and W est G ondw anaiand extendin2 from East A frica into the Sor pp.358-366 T ondarre M ountains of cast A ntarctica (Ro(,ers et aL, 1994 ). This D alia Saida. L, V jrela. R, and C in}olani, C , 1993b, A pre-C arbonifel-OLIS teC- tonic m odel in the evolution ot southern South 八merica: Com ples Rcn- m a tter is u nreso lved , bu t othe r au th ors ha ve stre ssed that the struc- dus X11 International C ongress for C arboniferous-Pennian, Buenos tural influence of N coproterozoic to earliest Palcozoic events in Aires. v. I,pp.371一384. D ronning M aud L and is m inim al (M oyes, et al. 1993, Y oshida and- D alzic], J W D , 199J, Pacific m argins of Laurenlia and East A ntarclica-A us- V itanagCe (1993). C harnokitisation is southern India has been attrib- tralia as a conjugate Fift pair: evidence and im plications for an Eocarn- uted to a distensional regim e at 500 M a (Santosh, et al., 1994). brian supercontinent: G eology, v. 19, pp.598-601 Dalziel, I W 1), D alla Saida, 1, H, and Gahagan, L M , 1994, Palcozoic Lau- renti a-G ondw ana interactions and the origin ofthe A ndean-A ppalachian I he P acific m argin of G ondw analand m ountains systern, G eological Society of A m crica Bulletin, v. 106, pp. In Paleozoic tim e, the locus of geodynam ic activity shifted to the 24 3 - 2 5 2 . De W it, M , Jeffery, M , B ergh, H, and Nicolaysen, L, 1998, G eological m ap m argins of G ondw analand (Figure 5). W hilst accretionary processes of sectors of、C .ondwarra: A m erican A ssociation ofPctrolcum G cologi.sts, dom inated at the Pacific and Iapetus m argin. rift ing and calving of I ulsa, O klahom a and U niversity of the W itw atersrand. Johannesburg terranes proceeded in the A valonian-C adom ian and and C im m erian D u Ton, A L, 1937, O W andering Continents: O liver and Boyd, Edin- provinces of G ondw analand. T he R oss-D elam crian m agm atic arc burgh, 366 pp. w as active along eastern A ustralia and Last A ntarctica, and the Fernandes, L A D , T on-un asi, A , Porcher, C C , and V auchez, A , 1992. K inc- Lachlan T hom son active m argin w as situated offshore. W est ofthe M aliC e%'Oftnif)n ofD om Feliciano bell during the Byjsifiano cycle. 24th R io de la Plata craton there w as a com plex exchange of terranes Congress, G eological Society ot'SOUlh A frica, A bstracts. Blocrulotnein. betw een th e A m azo n ian c rato n and L a urcn fi a th at resu lted in the fo r- pp. 127- 129 . m ation of the Fam atinian collisional orogen and transfer of the Pre- G ressc. P G , 1990, Developm ents in Pan A fircan g1e o lo g-y1 in southw estern cordillera terrane from to G ondw ana (D alziel, 1992 A frica: Abstracts 15th C'0110(fle de G eologic A tricainc , N a ncy, France, p.254. D alziel et al., 1993; D alla Saida ct al., 1993a, b). T he Pam pean G rcsse, P G , H o ffm ann. K 11. Sadow ski, G R , C esar, R F. M achado. R , S ul- exotic terrane and the A requipa terrane w ere possibly detached from tan, M , and U nrug, R , 1994, Landsal interpro ation of N eoproterozoic the w estern m argin of the A m azonjan craton, follow ing the Late- c ru stal fea tu re s o n th e w e stc rn sc a b o ard o f N a fn ib ia a n d S O LO A frica : N eoproterozoic break up of Laurentia from A rnazonia (G R Sad- ProteFOZOIC crustai and nictallogenic evolution, Abstiacts. G eololgical ow ski, personal corn m u m c ation, 1995). SOCiCty W Id G eOlOglCal SUrvey of N ainihia.W indhock.

M a r c h 浅 lim e 1 9 9 6 G roenc,Aa id. P B, G rantham . G H , and W atkeys, M K } 191) 1, G eological c} i- M etcalfe, 1, 1994, G ondw analand dispersion. A sian accretion and evolution d c lic e Io r a P ro te ro z o ic to M eso z o ic lin k b etw e e n so u th ea ste rn A frica an d of Eastern Te(hys: A bstract' 12th A ustralian Geological Convention D ronnin,} M aud Land. A ntarctica: G COIO,iCaI Society JOUrnal %. 148, pp G eological Society ot A ustralia. Per山 W estern , p. 28. 1 1 15 --1 12 1. M oores. E M . 199 1 .South w est U S- E ast A ntarctica (SW E A T ) co nnectio n::、 G rocne}Nald, P B. 1993, Correlaiion o 'ciatonic and orogenic provinces in hypothesis: G eology v. 19, pp.425-428. sonth-castern A j'rica and D ronning, M aUd ].and, A ntarctica. in Findlay, R M osley, 11 N , 1993, Gcologicjl evolution of the late Proterozoic ‘M ozain- IL I-I;nt-H,(. R. Banks, M R. and V ce%crs. .1 .1 eds., G ondw ana Fight: hique Belt" ot'Kenya: Tectonophysics, v. 221.pp.223-250. A sscm hl}, evolution and dispersal: A A Balkcm a, Rotteidam , pp. M oyes, A B, Barlon, J M , and G rocnew ald, P B , 1993, Late Proterozoic to I I f一12 2 . Farly Paleozoic tectonism in D ronning M aud Land. A ntarctica: super- K ilhich, I W , 1992. A SaIdanian decollcm ent com pared to other late Pro- continental flagmentation and am algam ation: G eological Society Jour- tC1-O/OiC CRIStal (ICCOUP1111, Zone、川 、outhc阳 A lrica: 24th ('oti,,rcs,, nal, v. 150. pp.8 13- 842. Geolo,-,ical Society ()}South A frica, A bstracts, Ifloeint'ontein, pp M yers, .1 S, 1993一[Irecam brian historv of the W est A ustralian craton and 16 3 16 7 adjaccrnt orogcns: A nnual Review of and Planetary Sciences, v. 21. H arris, 1, 13, 1993 , ( orrelatio ns O f tectonotherm al c\ ents betw een the central pp.4 53--485 Indian tectonic zonc and tile A lbany m obile helt ot'W estern A ustralia, ill M yers, J S, Shaw , R D, and Tyler, I M , 1994, Proterozoic tectonic evolution Findlay, R 11, U 111-UL, R , B anks, M R, and Veevers, J J eds., G ondw ana ofA ustralia: A bstricts 12th A ustralian Geological Convention. G eologi- Fight: A ssernhIv. CVOiLnion and dispcisal: A A Balkeina, Rotterdam , pp. Cal Sociciv ofA ustralia, Perth, W estern A ustralia, p.3 12. 16 5 18 0 . M yers, J S, 1994, Proterozoic Sutures and fold belts in W estern A ustralia: Harris, L B , 1994. Gondwanan tectonic setting tor U pper Palcozoic and Abstracts, 9th international G ondw ana SylupoSiUrn, H yderabad, India M eso/oic deform ation in the Perth B asin and Y i1garn C raton, W estern pp. 14 2- 143 ALISAI-dlia: 9th Intei-national G ondw ana Sym posium . Hyderabad, It]山}t N ance. R 1), and M urphy, .1 13, 1994, Contrasting basem ent isotopic signa- Ahstracts, 1). 151 lures and the palinspaslic restoration of peripheral orogens: exam ple front H arris, 1, B , and B eeson. J, 191)4, C orrelatio n of L ow er Palco /oic deform a- the NeoproterozoicAvalonian -Cadornian belt: Geology, v. 22, pp. tion c%cins in the V indhVan SUpergroup. central India and the Stirling 6 1 7- 6 20 2 . Range [,orm aiion, W estern A Ustrafia: 9th International G ondw ana Syni Purientel, M M . and Fuck, R A , 1992, Ncoproterozoic crustal accretion in posium , Hydet ahad, India. A bstracts. p. 159 central Brazil: G eology, v. 20, pl).375-379. H am s, 1, B , 1995. C orrelation hetw een the A lbany. Fraser and D arlinL Pinna, 11, Jourde,(;,Calvez, J Y , M roz, .1 11, and M arques, J M , 1993, The m ohilc bch}()(W estern A ustralia and M irnyy to W indm ill Islands in the M o/m rihiciLle belt in northern M ozam bique: N eoproterozoic (1 100-850) cast A nlarctic shield: Im plications for Proterozoic 6 ondw analand recon- M a Crustal grow th and tcctogcilcsis and supetim posed Pan A frican S U LIC tiO n s. ill Y o s h id a, M a nd S a n to sh M . e d s ., In d ia a nd A n ta rc tic a d u r- (800--550 M al tectonism : Precam brian Research, v. 62, pp. 1-51). m g, the Prccam hrian: G eological Society of' India M em oir 34, lip.47 -7 1 Po"e ll C M cA ., 199-5, A re Neoproterozoic placial deposits preserved oil the Henry, 6 . C lendenin一C W , Stanktrcet, I G , and M aiden, K J, 19()()一M ultiple m aigin of U U-11-CIIIIJ related to) Itagnictitation of' tw o supci--continenis'l- dclachnicni m odcl Im 山c carly riftinL of the late Proterozoic D am ara G eology, v. 23, pp. 1053 1054 orogen in N annhia: G eology. v. 18. pp,67-71 Powell,(’M cA , Li, Z X, M cElhinny, M W , M cert, J G , and Park, J K , 1994 H o llm an , P F, 199 1‘D id the bicakOLn Of LaUl-ClItia tUrn ClOnd'A analand Palcom agnetic Constraints of) tuning of the N eoproterozoic breakup of' inside-out?: Science,、.251 pp. 1409一14 12 Rodinia and tile C am hrian form ation of(Jondw ana: G eology. v. 22, pp 8 8 9 - 8 9 2 . Jar山川‘Ic Sa. E F. Sa, J M , and M acedo, M IL 1990. M ono- and polycyclic P ro tejo z o ic b elts in N E B ya z d : c o rre la tio n s w ith th e P a n -A frica n b e lts in Powell 〔’M cA ‘1993, A ssem bly ()}一6ondwanaland- O ficri foram , in Find- W est A frica: A bstract} l5th Colloquc de Geologic A fricaine. 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