evolution of the southern margin of tethys (north ...searg.rhul.ac.uk/pubs/audley-charles_1988 n...

Evolution of the southern margin of Tethys (North Australian region) from early Permian to late Cretaceous

M. G. Audley-Charles

ABSTRACT: A mid-Permian rifting episode appears to have removed continental blocks (now forming parts of Asia) from Australian Gondwana, but the present continental margin of Northern Australia-central New Guinea was formed by a later episode of rifting during the Jurassic. With the exception of the north-west Australian offshore region west of the Scott Plateau, this rifted continental margin has been greatly modified during the Cainozoic by collisions with arc-trench systems. Collision resulted in fold and thrust mountains, locally with ophiolite emplacements, that now characterize most of northern New Guinea and the Banda Arc. The identification of the Australia-New Guinea rifted continental margin in what is now the fold and thrust mountain belt of New Guinea, islands of the Outer Banda Arc, East Sulawesi, and Buton, rests largely on stratigraphic correlation and the recognition of the pre-rift sequence, breakup unconformity, and the post-breakup marine transgression and prolonged subsidence in these now highly deformed rocks. One implication of the Jurassic continental rifting is that the pre-rift rocks of the region accumulated in an intracratonic basin of eastern Gondwana. Another important implication is that the continental blocks rifted from the Northern Australia-central New Guinea margin must have drifted northwards towards Asia as the Mesozoic Tethys ocean spread across the tropics and equatorial region. These continental fragments of Gondwana collided with parts of south-east Asia that had been derived from Gondwana in an earlier phase of rifting.

Introduction

Since the recognition of the late Jurassic magnetic ocean-floor spreading lineations in the north-east Indian Ocean adjacent to the con- tinerktal margin of north-western Australia (Veevers and Heirtzler, 1974), it has been obvious that a very large continental block (or several blocks) must have been rifted from Northern Australia and central New Guinea (Figure 1). Furthermore, the petroleum com- pany seismic-reflection surveys of the north-west Australian shelf revealed abundant indications of extensional tectonics during the Permian and Mesozoic, with a major breakup unconformity of late Jurassic-early Cretaceous age (Powell 1976; Falvey and Mutter 1981, and many others). Hamilton (1979) drew attention to the indications that a rifted continental margin must be present in central New Guinea, where its age appeared to fall within the range of late Triassic to mid-Jurassic. Pigram and Panggabean (1984), calling upon the available stratigraphic data in New Guinea and some of the islands of the Banda Arc, were able to recognize the breakup unconformity, and subsequent marine transgression with subsidence, in New Guinea and part of the Banda Arc. However, Pigram and Panggabean (1984) built their interpretation on

the concept of microcontinents, which they postulated wherever they recognized indications of distinct crustal blocks (Fig. 2). In doing this they were not concerned to demonstrate the evidence for oceanic crust being created or destroyed between their postulated microcontinents, and neither were they aiming to identify the usual diagnostic continental margin sequences and structures of shelf, slope, and rise. Some criti- cism of the details of their interpretation and methodology has already been made by Dow and Sukamto (1986). The stratigraphy and structure of the region seem to offer little support for these postulated microcontinents, and in some cases these data appear to conflict strongly with the concept. This applies particularly to the Banda Arc.

This paper presents a summary of the stratigraphic information available from the com- plexly deformed region of the Banda Arc and Sulawesi, and attempts a correlation with the data from the Australian shelf and New Guinea (Figs 3, 4, 5, 6, and 7). From this, the breakup unconformity and subsequent subsidence with marine transgression have been interpreted. The series of palaeogeographical maps (Figs 8, 9, 10, 11, 12) follow an interpretation of the

From AUDLEY-CHARLES, M. G. & HALLAM, A. (eds) Gondwana and Tethys Geological Society Special Publication No. 37, pp. 79-100.

80 M. G. Audley-Charles

10 ~

120 ~ I

FLORES

1 4 0 ~ I | i

-"-':"?-.-'~-":,;'-',-;'_'-;v'i':' Collisional fold and thrust mountain belt ~/~//~,~/. I •1 Or , " SI'-/L X/C/N, \" " " - - , 9 / - , , - / - , , " - - " Ac t i ve vo l can i c a r c �9 �9 �9 �9 ' ' - , ' - , - . ' ~ - ' f , / I - ~ : C - .

- ~ - ' , c c-, , - z J ' - , " , - ' , . . . . . . , , _ . . . . . - , , . O c e a n i c c r u s t S ' , ~ ; " -

HALMAHERA S , - . ' - O , , - < , c , , - / ' , . ~ - , . , , / _ . . _ . , _ . ' - ~ v ' ; , - - , _,> 7 , ' - L . " ~ _ , - " ' " . . . . " 7 7 " - ; - ~ 3 4 ) L ' Z " , x ' ) / ' x ' - i ' , ' i . ~. - - ' L ' 5 "1 "1 ~, ~" '- ' L " . ~ l ; -

. "' , -"Y-7/ \ f Z ( q . , ; , - -C ,j . . . . .,< . . . . ,_ . , . -

0 NEW "'r'~4

G U I N E

q:b

Gc~

A U S T R A L I A

k '-,'coi~Z.

SEA'

Jurassic rifted continental margin i i

Cenozoic rifted or strike-slip ,. ., continental margin

! i i

FIG. 1. Location of the Jurassic rifted continental margin of Australian Gondwana and its modification by Cainozoic tectonic collision.

evolution of this part of Gondwana put forward by Audley-Charles (1983b, 1984). This may be summarized as the development of a rifted continental margin in the middle Permian, as Iran, North Tibet and Indo-China were removed by the creation of the new ocean Tethys II, followed by another episode of continental rifting

in the Jurassic which, by spreading of Tethys ocean III, removed South Tibet, Burma, western Thailand, Malaya and Sumatra. It was this Jurassic rifting that produced the present continental margin of northern Australia- central New Guinea.

Evolution of Tethys southern margin 81

1120OE _0 1130~ " l

( ' / ~ [,-~..~ Western / - ~! c~ _ .Obi-/~k,\ ~ Irian Jaya 0--to

/ L d , ~ ,~, Banggai - ~ i ! ~ i ~ . ~

~' ~ L . . 3 " ~ ~ Buru- Seram " - (~ 5 ~ L _ ~ ~ ~ ~ ~ - .. ~A,~ , ~

0 ~ ~ a n a a ~ e a r,, j u Buton ~-JARU

/ ~ L o BABAR ~TANIMBAR

~ 1 ~ SERMATA

C " ~ MBA f ' k ~ 0 km 500 - ~ SAWU ~ , , , , , , ~0o~

I o ~ R O n I

FIG. 2. Concept of microcontinents, applied to breakup of Australian Gondwana by Pigram and Panggabean (1984). Their proposed microcontinents are ornamented.


SAVU ROTI TIMOR TIMOR LETI

reef alluvium ~ reef alluvium ~ reef alluvium ALLOCHTI-tON ~ reef sandy marl & tuff ~ Noele M a r l ~ Noele Marl Batu Put ih ~ Batu Putih ull Bobonaro Scaly Clay Limestone ~ Limestone [ ~ & thrust sheets

marl emplaced in Mid-Pliocene Bobonaro Scaly Clay / I ,~-,I with exotics of E]obonaro Bobonaro |~ ~ = ~ J shale Miocene Cabtac Limestone, dy Clay with Scaly Clay with | ~ .J_--_L [ Permian Maubisse Fro., otic blocks exotic blocks | J = serpentinites &

o , ts below: as below: ~ marl ~ Aileu Fm. & Lolotoi Complex,

shale ~, and para-autochthonous radiolarian ~ radiolarian ~ ~ | J...m_..~_~ =~ exotic blocks

..L I marls 8 ~ | I ..L ~ I marl -=. marls, .J_ _L J pelagic ~ P . / / pelagic muds J - I shales & ~ ~ | ~ marl ~, ~ marls

/ / ~ radiolarite i ._L chert ,I

storniosphera| 7 ~ radiolarite

'EAKUP U N C O N F O R M I T Y ~ in . . . . . . . . I . . . . . =. . . ~ radiol, shale ~ BREAKUP U N C O N F O R M I T Y - " -'---- ,=--- ~ m glaucnnite l ~" �9

marl sst. silt / shale shaarlle / ~ marls ammonites est. marl J

radiolar/a- ~ Aitutu Rhaetic "Is Mbr." Halobia Imsts. Limestone Aitutu Lms. Aitutu

quartz Babulu Fm. Babulu I Limestones Fm. ~. Babulu Fm ~'~ marls turbidites turbidites ! turbidites

radiolarite Niof Fro,

~ Cribas Fro. quartz turbidite sandstone Atahoc Fm.

turbidite

FIG. 3. Proposed correlation of sections in some Outer Banda Arc islands. Data from mapping in Savu, Roti, and Tirnor by Audley-Charles and others, for Leti from Van Bemmelen (1949). Stratigraphy of Timor partly after Cook (1987) and Bird (1987).


I , . ,,,MQU~,T. I ~ reef

5 ,,o, z

0

~ k 0

< red limestone Lu E ? shale

radiolarite

S E R M A T A

Leti, Moa, Sermata & Babar appear to expose thrust sheets comparable with those of Iimor and fields of exotic blocks derived from Bobonaro Scaly Clay. These exotic blocks are derived from "Asian" thrust sheets & para-autochthon Australian facies shown here. Some of the para-autochthon may be in situ.

L

M

E

BREAKUP

~ Babulu Fm. turbidite

B A B A R

reef

UNCONFORMITY ~ marly Imst.

ferruginous geodes

~ Bahulu Fm. with tufts

T A N I M B A R KAI

= L ~ l ~ reef alluvium . . . . . . . reef alluvium

~ pelagic emplacement calcarenite . . . . . . chalk" ~ j of blocks Tanjung ~ Complex ,- & pebbly = ~ Matot -q mudstone Complex i ~ Batimafudi Fm 1 thrust ~ Weduar

sheets femangol Fms or in situ

~ ] Tangustabun thrust ~ Elat Fro. sheets Yahitimur

~ F m . or in situ Member

Two different interpretations:-

1. These early Miocene & Eocene shallow water limestones may be similar to deposits unconformable on overthrust metamorphics in Timor & Seram. In contrast, the Australian margin facies of this age occur in Timor (Ofu- Wai Bua Fms.) and in Seram (Nief Beds) where they are very deep water Mites, suspected to be present at depth unexposed in Tanimbar & Kai.

2. These early Miocene & Eocene shallow water limestones are Australian shelf deposits. The deep water Australian continental rise and slope are not exposed.

F1G. 4. Proposed correlation of sections in some Outer Banda Arc islands, based on data from Van Bemmelen (1949), Sukardi and Sutrisno (1981), and Achdan and Turkandi (1982).


I, sf f I I , I . Bu BANGGA,- AGE A M R U T O N S U L A M I S O O L

QU~AT. I ~ ' : : 1 reef alluvium I I ' e m p l a c e m e n t ~ reef alluviuml-[--L-~....-- I reef alluvium ~ ~ reef alluvium uJ I eL IO I ~ f s ' a n ~ s t ~ of"Asian" I - ' . . - - - - - ' lner i t i c I~'_'._:-:::'| neritic ~ limestone I i ! i

r . . . . '"('" "~l ' , t thrust sheets __EE'TZL-'~'___ r--'- . . . . . 5 I I--~"'~ . . . . . H i and Salas ~ neritic I I ' I ' ] limestones L I j I i I I I i I limestones I_,_-'-..,_ I .,e, Begs I [ Block Clay I -~ - - -%1 sandstone [r=------r~-..-.~ & shales (.9 I , J r , I I ..q I MIO I ' / I . ~ :~ . . - . - I shale I "Tectonism" i , ,

I / I " " " - ' - " "-I volcanics I " " 1 " " ' T 1 " "l-L "-L I -- , -- I Nief B e d s I I: r' : ~ : ~ 1 . . . . nerltic "=- ; - ~ - " Kasim Marl

"' 'O,,G ; - ' / I~" -~ ' -~ ' - t hathyal i' ' ' i ~hmestone

5 I . / | ' neritic I i I I I - - . _L l i / I -J- -J- I I J- "J- I Tobelo Beds limestone I I

~ I E o c I "-'- II I I ._L Ibathyal I --L IPelagic I I Zaag I - L - - L I / . . . . . I I . -L- -J- . l l imestone I-J- ._Llbathyal I I i = Limestone

_~1 I --=- I t Nle[ Bees I I ~ -'-" I marl I J - I I I

~< I PAL I:E=~::~/ / I-~%-I che" L ' t:'-'::-:.'.:.:.':., Oaram =st. I- - € I I'Z-IKumaFm, TobeloBeds ~ Yah'Member Fafanlap Fm.

L / / I - - " I hathyal I -- -- I pe,agic red marl sandstone / I _L . I I -J- I & white

I : , 1 / I L : I I- - il c'e , ' ' , Nlef Beds limestone I i I I Facet Group

I , , I pelagic / I - L I I J - I limestone E bathyal I I

I - - - - I , % TM / ~ l } e l a g ic I - , "- I marl ~ ~ l 1 limestone

i--L ..L I . . . . . . / i ' 1 ' l ; limestone I -L-- ' - --L I B m - ~ - - ~ IL'~---'-----I L ~ / I~---_--~-I Meta Fm. ~ a u Beds shalemarly Lelinta Shale

M ~ ~ ~ R E A K " I'~'~'~------"~ b a t h Ya ' ~ Demu Lst. I . " . " / --1 Wakuku ~ ~.,~P I U N C O N F O R M I T Y BREAKUP hathyal I~--.. ~-I Beds / ~ , i , = . , . . . - ~ ~ ~ ~ ~ - = . . . . . ~ Yefbie Shale

F I'~-:---.1 turbidites / ~ p - - r - L T I O g e n a ~ \ - ' U N C O N F O R M I T Y 1 | ' , ~.-I I ~ ~ Beds rO L ~ - I Saman / ~ Ghegan Fm. I - [ - - ~ . - ; I . . . . ~ Bogal Lst. - - [ , . _7~ . ' § Saman / ~ Balan Fm. i~:~....~.z.i win[o BeClS VVV"~VV acid ~ Keskain Fm

M I-J--i~(.-~l Limestone | ~ turbidites L-'L-Jf.=_-7%-I ~ volcanics ~ turbidites < ~ I~.. '-: - :1 (radiolaria- I I . . . . . r ~ ~- E I~'~'--:-'-T--'I Hal~ I ~ I I - : - -~ i calcilutite) / ~

~ L ~ ~ Rana & ? metamorphosed I I ,_ ' I Wahl I ~ . ~. Ligu �9 . ua - me[amorpnics turbidites " I I ~ t . _ ~ I Com"lexes I ~ C~ metamorphics metamorphics

I / - F~G. 5. Proposed correlation in some Outer Banda Arc islands based on data from Van Bemmelen (1949), Audley-Charles (1978), Audley-Charles et al. (1979), Tjokrosapoetro and Budhitrisna (1982), Smith (1983), and Pigram and Panggabean (1984).


A(~E

0 k

~: E (.9

L (..) ~ M <

E

L oo < M 13:

E

MISOOL

sandstone ,, , , ,

~ ~ J ~ ~ Facet Group ~ ~ ~ j ~ bathyal

~ ~ limestone J I i I . . . . _ - - ~ - - Lelinta Shale

i i i DemuLimestone _

_ _ _ bathyal Yefbie Shale

_ _ _

UNCONFORMITY

Bogal Limestone Keskain Fm. turbidites

P E R M I A N ~._b~-~] Ligu metamorphics

CARBONIF.

~ Tipuma Fm.

~ Aifam Gp.

~ Kemum Fm.

BIRDS HEAD WEST CENTRAL RANGES CENTRAL 8- SOUTH IRIAN JAYA IRIAN JAYA PAPUA NEW GUINEA

�9 . . . .

~ . . . . . . . . , : : : . . . . '

" _ - " ~ ' . JassFm " ~ Undivided - - Mudstone Kembelangan ~ ~ ' u - - ~ . ~ - -

.~::":.~.,-,~,-,..,~. ~ broup - - ~ F ~

"~ . : ~ ' . " . . " " " " ~ - - ~ Maril Shale .~. "~: . m - - - -

P O S T B R E A K U P UNCONFORMITY " -'k~. Balim.bu Fro: : ' i

Volcanics ~ . ~ : , L p " ~ , . " - I NOONFORM, ara

~ v " Tipuma Fro. ".'---~..- " ~ ' ~ :':''vO'" " ~ " " "'[: ]'" "~' . " , v ' ~ _ _ - - ' ~ " ~ ~ v . : Jimi

"x~" . ".bl : : . . . . .o . . Kwatisore ~ Volcanics ~ ' ' 'v- ' r r '~ - ~,:-, ? c,4. ? . . ; : ~ ~ ' : : : " ' ~ " " ' " Graniteo ~

Kubor Kimil Diorite ~"..'.'-~-~..'.'... ~ . . ' . . ~ : ".'~'" Granodiorite

-..---.-- -/-- Omung & Bena Bena Meta. ~ ""

FIG. 6. Proposed correlation of Misool and New Guinea from Pigram and Panggabean (1984).


DSDP N.W. AUSTRALIAN SHELF TIMOR SITE 262

km ~r ~' ~, 0 ~ OUATERNARY

i , ' , ' , ' , ' , ' f r i ng i ng r ee f I _ i _ 1 . . . . . . . . . . . . . ~ , , , , , I PEIOOENE IL - - ' , . : - - ' . ; . - - ' L I I - - I - / I , , IU f f / I :MP I .R i ' I T ,~ " ~ = I I I I / NEOGENE

UPPER PLIOCENE F'-L-"--'" --.-'-:"J i /~TE~PLIO~CENE i' : ' : ' : ' : ' ~ PA~EOGENE 1:" "--" "-" ~lP~176176 enic ~ J ; ' , ' , ' , ' , ' ,I ' ' " ' . ; - " �9 ' ~ . s ' ' , , , , , l

~]'": .'.'_C.. ~'I fac'es ~. ~ . , ~ f MARINE I, ', ', ', ', '! CRETACEOUS LOWER QUATERNARY I:-- .-- ' ." .:_-I ~ % ~ " " ], ' , ' , ' , ' , '] . . . . . . . . . . . . . . . . . [':."!i!!ii~{'iiiiii!~i!{i-.'~. ~ " k " ~ SHELF FACIESL--------.-J UP JURASSIC

2" -uvvc, uu~.c,N/*,T . . . . . ,~,~":,..r I-- -- -- I 5 km THICK NAPP_.P~,~ c-,~ "~

~ . i - f ~ MID. JURASSIC

- ]_L N __LIContinental slope J ~ . ~ . ~ . f ' . " ~ " . ~ . . . . . PALAEOGENE ] ~ _1_ . ~ - ] " rise facies 0~s fluvial~i':~!i:.~ii~i] TRIAS

4- UPPER CRETACEOUS-]" :.j_ ~ I , j ~ - ' : ' : , ~ - ~ - I . _LI ~ ~ ~ PERMIAN

o ,c, ,c,ous 17--o 4 UPPER J U R A S S I C ~ f ~ shelf limestone

MIDDLE JURASSIC ~ very shallow "~ calcilutite with radiolarians ~ ' -~- - ' - -~- - I marine

6- - - LOWER JURASSIC--I ~ ~ " sandstone marl

].~ ~. ~. ~ high TRIAS ~ i organic _content

anoxic PERMIAN horizon

I NTRACRATONIC BASIN FACIES

TIMOR DSDP 262 o I~. ~.I _

km , 150 km

NW

lime mud

radiolarite F ~

chert

shale

siltstone

sandstone N.W.

AUSTRALIAN SHELF

1 SE

FIG. 7. Correlation of stratigraphic succession in Timor and north-west Australian shelf. (After Audley-Charles 1986b.) Note that both pre-breakup sections accumulated in an intracratonic basin. See Fig. 14 for pre-collision sections.


30 ~

~--~-~ T E T H Y S I

~oo~--- S.

INDIA \ x q \ kHigh \~ k '~Himalaya /

I N D I A " ) / / /

ii1,, TIMOR

"11./ ~/,,/,%

%,

W. BORNEO

30 ~ S.

Incipient Mid-Permian lithospheric rift

Subduction trench

Fluvio-deltaic sediments :";iiiiiiii!!i!!ii!i:):ili! !5i:

Turbidite intracratonic bas in 4111111111Ilia, Marine glacial diamictites

Ice sheets = ~,,,~,~, ~,~,,,.~- Mountain glaciers ~_

Possible further extent of mountain glaciers ~: ?

Volcanoes z~ z~

Sedimentary transport direction

FIG. 8. Palaeogeographical sketch map of Australian Gondwana during late Carboniferous to early Permian times (modified after Audley-Charles (1984)); Permian sediment transport directions from Bird (1987). Outlines are for reference only.


# / ...-.m...~. ....... .~-. �9 .-:r...-:v .......................... ~ - -k~ '~ l~" . . . . . .

/ # 0 o.

S. - . . . . .

_~-

ANTARCTICA ! . . . . . . . .

J ~ """ "" z Non-accumulation or erosion ~ Shallow marine limestone . ' , , : . :

Land areas undergoing erosion i:~o~i:oio:)i:.: Shallow marinesiliciclastics : : : : : : : : : : : : : : : �9 �9 �9 Acid-intermediate volcanics i!!!iiiiiiiiiii Marginal marine siliciclastics

C

FI6.9. Palaeogeographical sketch map of Australian Gondwana during late Permian to early Triassic times. The warm current was proposed by Robinson (1973). Outlines for reference only.

E v o l u t i o n o f T e t h y s s o u t h e r n m a r g i n 89

0 ~

3O ~ . S,

. . . . - - - - ~ - - - - - - - - - - - - - - - " - - - - - - - - - - - - ~ Z Z _ ~ Z - _ - - - - ~ - - . . . . . . . . . . . . - - - _ _ _ _ . . . . . . . - - . . . . . ~ - - - _ _ ~ . . . . . . . . . . . . . . . . . . . . . . .

- - - _ _ _ ~ _ - / - - . . . . . .

. . . . . t - - - - - - T E T H Y S 1-1 . . . . . . . . . . - _ _ - - . . . . .

. _ 2 ! - : - : r . . . . . . . . . . - - - . . . . . . ~ - ~ - : : - - - - -

_ _ _ - : \

t \ . . . . ~ _ _ _ - _ - - - _ - _ - _ - _ _ _ . . . . . . = o ~ - , ~

" ~ . " . . - ~ _ Z _ - _ - - Z - _ - - - - - - - - . . ' " ~ " %. " . o . . . . . . . . . . . - _ - - - _ - - ~ - . - " o ~ o ~ ) o,

+<.::: ............ ::i!i::::::::F: . . . . . ~ . . . . . ::i!:::?: I I ' " : : : : "

......... �9 Continental margin

Sedimentary transport direction

Calcalkaline volcanics

v v Subduction trench ~ Limestone with H a l o b i a

Marine silicictastics (including turbidites) !!~i:~i!:i!!

�9 �9 �9 Shallow marine siliciclastics ! ! ~ i ~ ] . . . . . . . . . . . . . . .

Land areas ( ~ Norian coral reefs

FIG. 10. Palaeogeographical sketch map of Australian Gondwana during late Triassic times. The warm current was proposed by Tollmann and Kristan-Tollmann (1985). Sediment transport directions from Cook (1986). Outlines for reference only. (Partly after Audley-Charles, Ballantyne and Hall (In press).)


W.BORNEO �9 ~ "'....~ T E T H Y S 11 . = ~ ' r ~ ; . ~ . ,

- ~-..~.~o..~o v (~W.SULAWESI

t "---"" ~o-~ ~ ~ ~-~:----" ~" ~~ ~ \ ~ "~A'LOCHTHOJ

so \ ~ :~ - ~ - - ' ~ ' . . ~ . : ~

,,,,~ ' ~ ~~"-!::-::-~--:--::::----:::-- -,,,.,).~ ,,~ ...-:::-:_::-::::::::_-

) ,," / ~ ~ ~ ~ '-:::::::::--

60"- S.

h

A N T A R C T I C A

~ ~ Land or areas of non-accumulation i!!!!iii!!i!~i~i Non-marine clastics

FIG. 11. Palaeogeographical sketch map of Australian Gondwana during late Jurassic times. Outlines for reference only. (Partly after Audley-Charles, Ballantyne, and Hall (In press).)

Evo lu t i on o f Tethys southern marg in 91

============================= / / ,.,o,,,o

"-C:;Z--:i--:i: : : : : : : :~::--:--:-- ~ ~ . LAYA'"~ ..... -~ '- ' ------ :- ' ---- ' - ' - ' - : - ' - ' -"-"- ' - ~ A L.A. YA~ a=;==~O~" . . . . . . . . ~E.BORNEO ============================================= -:-:-:-:--_ --:---7-:-:-:-:-:--:-:-:---:-:--J-. ~------.~URMA~ ~ ...... " - - ' - : - : -2 -_-_ ...... ~ r . ~----_-_~-::2------:-:-:--:-----/_-_ ....... :-- ~ .......... -_----_--_--_-----:-:-:-_-.-_ ....... ~ . . -~-_-- ~ Z-'-'-'-'---:---~~ -'~ ........... "~ _ _ --_-_---_----" --_--_----~-_--_----'-'-"-'-.'-.'~-Z BAN D A ~ : " ~ - ' - - > ' - : : : - ~ - - - - - - - " - ...... ------ gk ..-::::::.-.-..~L~oc..~_.?y~

s. ---------:-:+:-_---- --:+_--:-:-:-:-- . . . . . . . -::::::::::-:::: 3o ~_ ---~---------. - _ _ _ _ _ _ . . . . . . . . . . . . . . . . . . . __.__.._

""::.:--k-!:_::!:-4: 'K-:_:::--:!:!:!:!:!:

!iiiiiiiiiiiiiiiiiii iiiiik

................ Continent/Ocean margin

M Spreading anomaly . . . . . . . . . . . . . . . . . .

Land areas

Deep and bathyal marine sediments . . . . . . . . . . . . . . . .

: : : : : : : : : : : : : : : :

!i~iii~!!!~ Shallow marine sediment

Terrestrial deposits (Red Beds)

Fro. 12. Palaeogeographical sketch map of Australian Gondwana during early Cretaceous times. Outlines for reference only. (Partly after Audley-Charles, Ballantyne and Hall (In press).)

Identification of the northern Australia- New Guinea continental margin

The gravity survey data for the northern Australian shelf and Timor region of the Banda Arc indicate that the Australian continental crust continues below the 2-3-km deep Timor Trough to the north coast of Timor, where it ends abruptly (Chamalaun et al. 1976). Seismic refraction surveys in the Timor-Tanimbar Trough and over the north-east Australian shelf (Jacobson et al. 1978; Bowin et al. 1980) have shown that the Australian continental crust extends into the islands of the Outer Banda Arc (Timor via Tanimbar, Kai to Seram and Buru). Similarly, geophysical data have demonstrated

that the Australian continental basement continues from Cape York Peninsula below the Torres Strait into southern New Guinea (O'Brien et al. 1961; Vind and Harwood, 1965).

The lithofacies, faunas, and floras of the Permian and Triassic rocks in the Outer Banda Arc islands appear to be closely related to those of the northern Australian shelf (Fig. 14), as seen in seismic-reflection surveys (Powell 1976), and in the various wells on the shelf (Bird 1987 and Cook 1986). Similarly, the Cretaceous and pre-collision Cainozoic rocks of the Outer Banda Arc islands can be correlated with those of the north Australian shelf (Audley-Charles et al. 1979, Schluter and Fritsch, 1985). It has also been shown that the Mesozoic and Cainozoic deposits of the Carpentaria Basin (east of Cape

92 M. G. A u d l e y - C h a r l e s

York) can be traced from northern Australia into the southern part of Papua New Guinea (Smart and Senior 1980; Smart et al. 1980; and Veevers 1984, pp. 127-9). It has been argued by Pigram and Panggabean (1984) that the post- breakup unconformity can be traced from central and southern Papua New Guinea (PNG), where it is of early Jurassic or possibly even late Triassic age, to western PNG, where it is of Early Jurassic age, to the western central ranges of Irian Jaya, where it is early Mid- Jurassic in age. This transgressive unconformity reflects the marine waters flooding over the terrestrial sediments of the New Guinea hinter- land, as a consequence of subsidence of the cooling lithosphere. This subsidence followed the thermal uplift associated with lithospheric rifting and the initiation of spreading of new Tethys oceanic crust.

Hamilton (1979) and Pigram and Panggabean (1984) used stratigraphic and geophysical indications to draw the line, marking the edge of the rifted continental margin in New Guinea, as it formed in the Jurassic. Similarly, it is possible to draw this line in the region of the Outer Banda Arc although, as in New Guinea, the Australian continental margin deposits and the underlying pre-rift intracratonic basin deposits have been strongly deformed. They are now found in Seram, and in the southern Banda Arc islands such as Timor, strongly folded and thrust with a vergence towards the Australian continent. Although the present continental margin of Australia can be recognized on geophysical and geological criteria on the Banda Sea side of the Outer Banda Arc islands, it might be argued that the Jurassic rifted margin does not correspond closely with the present margin. This is because the late Cainozoic collision of the rifted Australian continental margin involved this margin underthrusting the forearc, so that the more distal part of the margin may have been subducted. However, the distal continental rise deposits of rifted margins accumulate on oceanic, not continental, crust. Thus, the posi- tion of the Jurassic rifted continental margin may correspond quite closely with the present margin, unless the continental crust has been subducted. The Chamalaun et al. (1976) view, based on the gravity data and supported by deep magnetic sounding (Chamalaun and White 1975)--that the present limit of the Australian continent corresponds to the northern edge of the southern Banda Arc, appears justified on the basis of the strata exposed in the Outer Banda Arc islands, for example in Timor, where Australian siliciclastic facies of Permian and Triassic age are exposed along the north coast.

Pigram and Panggabean (1984) interpreted the edge of the Australian continental rifted margin, in the Banda Arc region, as correspond- ing to the present axis of the Timor Trough. That view appears to be based on the interpretation of the earthquake data, i.e. that these data indicate Timor Trough marks the trace of the Benioff zone (McCaffrey et al. 1984; McCaffrey et al. 1985, and McCaffrey and Nabelek, 1986). This has been challenged by Chamalaun et al. (1981), Audley-Charles (1983a), and Price and Audley- Charles (1983). The Pigram and Panggabean (1984) interpretation ignores the gravity and deep magnetic sounding data, and takes no account of the exposed stratigraphy on the island of Timor.

The northern arm of the Outer Banda Arc, which includes the archipelago of small islands between Kai Ketjil and Seram, and also includes the island of Seram, is designated by Hamilton (1979) as part of the Australian continental block. Hamilton drew the continental margin at the inner (Asian) boundary of these islands. The geology and gravity field of Seram appear to be a mirror image of those of Timor, thus supporting the suggestion that the continental margin of Australia corresponds with the inner (Asian) margin of the islands of the Outer Banda Arc (Fig. 1). The reported presence of continental metamorphic basement exposed in Buru (Tjokrosapoetro and Budhitrisna, 1982), with only gently deformed Mesozoic and Cainozoic strata unconformable above it, suggests that Buru represents a detached continental block from Irian Jaya (Hamilton, 1979). The case for considering Buru as part of Mesozoic Australia is strongly supported by the stratigraphic sequence; its correlation (Fig. 5) has been discussed by Audley-Charles (1978), Pigram and Panggabean (1984), and others.

Hamilton (1979), and Pigram and Pang- gabean (1984), followed Klompe (1956) in regarding Buton and Sula-Banggai islands as detached parts of the Australia-New Guinea continent. The stratigraphic evidence (Figs 5, 6, and 13) for this has been discussed by Audley- Charles (1978), Smith (1983), and Pigram and Panggabean (1984).

The east and south-east arms of Sulawesi are usually regarded as integral parts of Sulawesi (Silver et al. 1978; Hamilton 1979; Pigram and Panggabean 1984). However, the presence of Australian-type shallow-marine facies of Trias- sic and Jurassic age, and the presence of deep- marine Cretaceous pelagic facies--imbricated with shallow-marine Eocene carbonates and fault slivers of ophiolite--in the east arm (Kundig, 1956) led Audley-Charles (1978) to

AGE

QU'AT. ~ PLIO

~ E_ 0 MIO LU Z L ~, OUG klA O EOC =,

~ PAL ~ k

8 <

~ E

~ k

~ M <

~ E

~ L if) ~ M <

~ E

Z k <

E v o l u t i o n of Tethys southern margin EAST SULAWESI BANGGAI-SULA

~ neritic limestones

overthrus Mid Mioc

r

r

BREAI'

olasse cies

lhrustin9 imbrication ~nd folding tallow atlorm facies it out by rusting? 1allow attorm cies Jt out b~ rusting. 'Jagic ~ep arlne =cies

Jt out by irusting?

t deep marine pelagic facies cut out by thrusting

auconite

UNCONFORMITY

intra cratonic basin sediments

~ neritic limestones

- -L _-L.j_ marl

_ _ shale

limestones

marl

~ conglomerates

acid volcanics

granites

metamorphics

,.~. FIG. 13. Proposed correlation of Sulawesi and Banggai-Sula from data in Westermann et al. (1978), Sukamto and Simandjuntak (1983), and Simandjuntak (1986). Note that the Mesozoic ophiolite may have first overthrust in the Palaeocene. The Miocene thrusting appears to be related to the collisional tectonics.

suggest that eastern Sulawesi was detached from Australia-New Guinea by rifting (Fig. 1). Recent work by Sukamto and Simandjuntak (1983), and by Simandjuntak (1986), suggests that the central Sulawesi province of blueschist and other metamorphic rocks represents a major tectonic suture. It separates the western Sulawesi Cainozoic carbonate platform and volcanic arc from the eastern province composed of Australian continental margin sediments and slices of ophiolitic ocean floor. If we look at the detail of this Australian continental margin, we see a 'basement' of Triassic and early Jurassic shallow-marine strata, which can be correlated with the intracratonic deposits of that age exposed in the other islands of the outer Banda Arc, such as Timor. These are overlain by late Jurassic and Cretaceous deep-marine, pelagic sediments deposited on the Australian continental slope and rise. All these sedimentary rocks are imbricated with Australian shelf carbonates and related deposits of Eocene to early Miocene age, and also with slices of ophiolite, probably representing part of the late Mesozoic ocean floor. Thus, eastern Sulawesi is interpreted here as an imbricate zone composed of

93

the Australian continental margin with slices of ocean floor and associated metamorphic rocks. This imbricate zone occurs between the bluesch- ists and other metamorphic rocks of the tectonic suture of central Sulawesi, and the relatively undeformed Australian platform deposits of Mesozoic and Cainozoic age that crop out in the Banggai-Sula islands--where they are unconformable upon eroded Permo-Triassic granites (Pigram and Panggabean, 1984).

One outstanding feature of the Sulawesi collision zone, is the apparent absence of the forearc accretionary wedge between the volcanic arc of western Sulawesi, and the collided fragment of Australia-New Guinea--represented in eastern Sulawesi. This absence of the forearc is remarkably similar to the Timor collision zone, where the forearc accretionary wedge is also missing between the volcanic arc and the Australian continental margin exposed in Timor. Accord- ing to Price and Audley-Charles (1983 and 1987), its absence from Timor can be explained by the overriding of the forearc by the ruptured Australian lithospheric plate; perhaps a similar mechanism has operated in the central Sulawesi collision zone.


CONTINENTAL EXMOUTH PLATEAU SE N W CONTINENTAL RISE SLOPE &

PROVINCE SHELF PROVINCE PROVINCE I TIMoRPROXIMALpRoVINcERISE I (PROJECTED EAST)

- - /

OI - - - - - / _ _ _ : '/- ------~ ."~-'-~..'~ ~ . . . . . . . . . . 7

__ _ - - __ :-_. f :,-----~ - , - ~ . . .,.. ,...,.._ , . /' - - ----- . . . . . j

Pa . . . . ? . . . . ? - - - - - - - -

K U - ABYSSAL TO BATHYAL ENVIRONMENTS

. . . . 1 0 0 M a - - - -- ~ SHELF-_----_----y

- _ _ _ _ _ _ .-_ ; ~ _ . . . . . . ,,

' . ~ ~ T H -_----_----_--- B A THY AL":--------------------~ ] KI -- : ~ __--- - - --~ : = :- :: - - ~ PLATEAU ~ - - ~ - - : - - : : - - - ~ / /

. .~ ,~- - - - . . . . - - - - - (SHELF?) .,we~-_---~MAJOR POST-BREAKUP-jb7~.'.7

Jm x ' , x \ . / N G ~ " X , , , ~ : . : _ c o . _ ~ _ : ~ . . . . . v . ~ " ~ , ~/AL[.E~ -- ~ ~ ~ ~ ~ ~N ~ "Nl: _'-~:. : T,MOR-- ~ . ? ~.. ' . " .~ : : . : . : . . ' - . . ' _~ , I 4: ;SEQOiCN(~E-J

.- ' : : C A R B O N A T E ~ ' ' . -" .- :: " . . " '" JI ~ ~ ~ N ~ ~ R A M r E ' j ~ ~.uv,:u.:..~..f.qE#;~C.......::}.~. E r o s , o n a l c y c l e

-- ~ ~ ~ ~ ?FAULT SCARP I ~ ~ : " ~ It Cann ing Bas in 2 0 0 M a TRu ~ ~ C O N G L O M E R A ? E - I ~ r O ~ Z ~ - ~ - - - - I ~

Pu _ i ? I ? LI ?. I ;" F luwo de l tmc a n d ' . ' ; . " " "" " "'- . .I .: . . . . - : " " "" " " " " : ' : " ' : : : : ' " :" ' " ' " "" """ t ~ ' " " : In t ra-cra ton ic . . - - ~ ~ i i c o n t i n e n t a l .- . : . . . . . . . . . . . ,.......... bas in

Pl , \ \ \ \ \ \ \ I : - : : : - t - ~ . - ~ t + - . - ' E ' : ' . ~ l ' . - = . ' . ' . ' : :.~:.'1" " . " . ' . " . ".1"-" ! : ' . ' : ' : : ~ i ' . ' l E " ' . t : J - ' : " . "

"~ INTRACRATONIC BASIN REMOVE l0 S,E. ASIA ~m d

IN JURASSIC - i

FzG. 14. Generalized time-stratigraphic cross-section of the northern Australian continental margin (after Falvey and Mutter 1981). Compare it with Fig. 7 to see the effect of collision of this rifted margin with the Sunda arc-trench system.

Stratigraphic correlation of Northern Australia, Banda Arc, Sulawesi, Buton,

and New Guinea

Summaries of the stratigraphic successions are presented in Figs 3-6, 13, and 14. These demonstrate that the characteristic pre- breakup, breakup, and post-breakup successions can be recognized and correlated throughout this huge region.

The basis for the stratigraphic classification of the rocks of the Outer Banda Arc, into allochthon, para-autochthon and autochthon has been discussed in detail in Audley-Charles (1968), and revised in Audley-Charles (1986a). Here we will just note that the para-autochthonous strata of the Outer Banda Arc and eastern Sulawesi are correlated with the successions encountered below the shelf of northern Australia and their outcrop onshore. The allochthonous rocks of the Outer Banda Arc were emplaced in the late

Cainozoic collision with the volcanic island arc, and hence do not concern us here. Similarly, the autochthonous rocks of the Outer Banda Arc which represent the late Cainozoic post- orogenic deposits are not considered in this paper.

Two outstanding features to emerge from these correlation tables is the predominance of siliciclastic facies in the pre-breakup sequences of the Banda Arc and Northern Australia, and the dramatic diminution in importance of siliciclastic deposits, particularly in the Banda Arc (and to a lesser extent in the outer part of the Australian shelf) after the breakup unconformity. The late Jurassic and early Cretaceous post- breakup transgression is characterized by muds, in which radiolarians and chert are important. They give way to carbonate mud with relatively little dilution by terrigenous mud, while silt and sand are extremely rare, particularly in the Banda Arc region, until the late Cainozoic, when the effects of collision with the Banda

Evolut ion o f Tethys southern margin 95

forearc result in the accumulation of siliciclastics.

In central and southern New Guinea, the proximity to a source of terrigenous detritus possibly led to the accumulation of siliciclastic deposits, including sand, after the post-breakup transgression. The more distal outer shelf and continental slope and rise deposits, comparable with those found in the islands of the Outer Banda Arc, probably occur at depth below the overthrusts in the mountain belt of the northern New Guinea province.

One notable feature of the pre-breakup sequence of the Outer Banda Arc is the palaeo- current evidence for the derivation of some of the siliciclastic sediment, from the northern 'Asian' side of what was to become the new rifted continental margin (Bird 1987). The high woody-fragment content of the Permian and Triassic sandstones in Timor (Bird 1987, and Cook 1986) and Seram (Audley-Charles et al. 1979) imply their derivation from large deltaic complexes. Such deltas have been postulated to characterize much of the region that now lies below the northern Australian shelf, which during the Permo-Triassic was part of the large intracratonic basin (Crostella and Barter 1980; Bhatia et al. 1984; Cook et al. 1985).

Rifting of the Northern Australian continental margin

Most of the late Carboniferous and Permian sediment under the present north-western shelf area is predominantly non-marine, with marine incursions (Powell 1976; Falvey and Mutter 1981). On both seismic reflection and well data, the late Carboniferous and Permian sediments amount to about 4 km thickness locally. There is also abundant evidence for tensional movements, block faulting, and considerable local subsidence to accommodate this thickness, much of which appears to be deltaic. These large-scale regional changes may be related to the major lithospheric rifting episode at the northern margin of this part of Gondwana, which has been postulated to explain the rifting of continental blocks tentatively identified as Iran, Indo-China, and northern Tibet (Audley- Charles 1983b, 1984). The presence (Metcalfe, this volume) of glacial-marine diamictites of late Carboniferous-early Permian age in northern Tibet (Changtang), Afghanistan, and Iran, indicates that northern Tibet remained part of Gondwana, at least until the end of the early

Permian. This further suggests a mid-late Permian rifting.

It may be important that, on the Outer Banda Arc island of Timor, Bird (1987) has identified sedimentological and faunal indications of sig- nificant changes in water depth in the intracratonic basin, which he suggests may result from Permian block faulting. This, together with the evidence of a major phase of Permian extensional faulting, from seismic reflection data of the northern Australian shelf (PoweU 1976), and the regional arguments put forward by Audley- Charles (1983b, 1984), appear to support the rifting of continental blocks from this part of Gondwana in mid-Permian times--with the spreading of a new Tethys ocean carrying these blocks to collide with Asia (Metcalfe, this volume). Metcalfe argued that because the Car- boniferous and Permian floras of Indo-China do not appear to be related to those of north-east Gondwana, we should therefore regard Indo- China as having rifted from Gondwana in the pre-Carboniferous. This apparent conflict might be resolved, if the warming influence of the Tethys ocean--at subtropical latitudes--adjacent to this part of north-east Gondwana, was sufficient to sustain a different flora along the seaboard of the continent. This is in contrast to the colder and much more severely continental climate of the vast interior of late Palaeozoic Gondwana. Robinson (1973) argued the case for a warm, equatorial, Tethys ocean current, turn- ing southward, and sweeping eastward, along the northern shores of Australian Gondwana during the Permian. Tollmann and Kristan-Toll- mann (1985) applied the same idea to the Triassic.

Seismic-reflection surveys over the northern Australian shelf have provided abundant indications of extensional faulting during the Triassic and Jurassic (Powell 1976; Veenstra 1985). Spreading of new oceanic floor, creating the north-east Indian Ocean adjacent to north-west Australia, occurred in the Callovian (Veevers and Heirtzler, 1974). It was the culmination of the extension tectonics that produced block faulting during the Triassic and Jurassic, and which resulted in the formation of the rifted continental margin of northern Australia during the Jurassic.

Seismic sections and drilling on the present shelf (Fig. 14) have found that some fault blocks moving in the late Triassic and early and middle Jurassic were strongly eroded, while elsewhere, half-grabens subsided (Laws and Kraus 1974; Veenstra 1985). The large-scale slumping and the slump folding in the Triassic and early Jur- assic rocks of Timor (Bird 1987, and Cook 1986)


Flo. 15. Breccio-conglomerate of clasts of Middle and Upper Triassic Aitutu Limestone, found at the margin of that formation, and interpreted as a late Triassic contemporaneous submarine fault-scarp breccia. Near Tilomar, east Timor. (See Fig. 14.)

may be regarded as the result of block faulting during the late Triassic and early to middle Jurassic. Indications of strong erosion in Timor during the Triassic are illustrated in Figs 15 and 16. Perhaps the most spectacular indication is that of the intraformational breccio-conglomerates (Fig. 15), interpreted as a fault-scarp deposit associated with the block faulting affect- ing the pelagic carbonate platforms (Aitutu For- mation). These platforms must have stood above the middle and late Triassic basin floor, where turbidites and siliciclastics of the Babulu Formation (Giani 1971) accumulated.

The principal indication of a regional structural event, that has a major influence on sedimentation and stratigraphy, may be seen in the exposed sections of Oxfordian-Callovian age in southern Timor. Whereas most of the Permo-Triassic and Lower Jurassic para-autochthonous deposits of Timor are siliciclastic sedi- m e n t s - m u c h of them turbidites deposited in deep basinal environments, the Middle Jurassic deposits exposed in southern Timor (e.g. in Kolbano and Aliambata) comprise glauconitic sandstones with belemnites and a thick-shelled coiled serpulid. At Aliambata a notable bed of lignite is exposed. Thus these Middle Jurassic deposits provide a striking indication of very

shallow-marine conditions, in contrast to the Permo-Triassic and early Jurassic deposits, and in even greater contrast to the late Jurassic- Pliocene deep-marine deposits above. These glauconitic sandstones, exposed at Kolbano and Aliambata, are overlain by pink, grey, and violet marls and calcilutites with Stomiosphaera, rare radiolaria, Cadosina and Inoceramus prisms. These sections appear to record the breakup unconformity marked by the glauconitic sandstones and ~he post-breakup transgression preserved in the fine-grained lutites rich in radiolaria and calcareous plankton, which represent deposits of the newly formed continental slope and proximal rise. Remarkably similar sequences are exposed in Seram (Audley-Charles et al. 1979). Furthermore, the manganese nodules in red clay, sharks' teeth, and radiolaria from the Niki Niki region of central West Timor (where they occur as exotic blocks within the Bobonaro Scaly Clay), represent deposits of the distal continental rise or even the bathyal floor of the spreading Cretaceous Tethys ocean (Margolis et al. 1978). These nodules are now located in central Timor, as a consequence of structural telescoping associated with the collision of this continental margin with the Banda volcanic arc in the middle Pliocene.

Evolution Of Tethys southern margin 97

FIG, 16. Intraformational conglomerate in the Middle and Upper Triassic Aitutu Limestone of West Timor. This indicates an important phase of relative uplift of the Aitutu carbonate platform during late Triassic times, resulting in the erosion of the lithified Aitutu Limestone. (See Fig. 14.)

Indication of Jurassic rifting in New Guinea

The evidence for a phase of lithospheric rifting, that had the effect of removing a continental block from the northern margin of what is now central New Guinea, has been discussed by Hamilton (1979), and Pigram and Panggabean (1984). The principal difference between the interpretation adopted in this paper and that of Pigram and Panggabean (1984) is that the latter take the view that western Irian Jaya (i.e. the Bird's Head and Neck including the Onin and Kumawa peninsulas), together with Misool, Buru and Seram, formed a separate microcontinent. In their view this microcontinent was

located far from the rest of New Guinea. This idea, and the stratigraphic arguments on which it based, have been challenged by Dow and Sukamto (1986). The very close similarity in stratigraphic succession throughout the Mesozoic and Cainozoic in Timor and Seram, and other islands of the Outer Banda Arc, argue strongly against Seram having been a microcontinent during that time.

Permian to Cretaceous palaeogeography

A series of palaeogeographical maps of the Northern Australian continental margin (Figures 8-12) have been based on my recent

98 M. G. Aud ley -Char l e s

interpretation of the rifting of this continental margin in the mid- to late Jurassic, and the identification of the continental blocks that were adjacent to Australian Gondwana until this mid- Mesozoic rifting event--as South Tibet, Burma, Western Thailand, Malaya, Sumatra, and the Banda allochthon. Aspects of this contentious interpretation have been discussed in detail elsewhere (Audley-Charles, 1983b, 1984, 1987, Audley-Charles et al., in press, and Metcalfe, this volume). One vital piece of evidence con- cerns the age of the major orogenic compres- sional event that strongly folded, thrust, and cleaved the Triassic rocks of the Malay Penin- sula. The general view (Metcalfe, this volume),

recently supported by ~eng6r (1986), regards this as a Triassic event. An expedition to investi- gate this problem in the field was undertaken in 1986. We found that the Carboniferous and older rocks of the Peninsula display multiphase penetrative deformation distinctly different from the Permian and Mesozoic rocks. We regard this as indicating a mid-late Cretaceous collision event. We found no evidence of a Triassic orogenic phase in Peninsula Malaya (paper in preparation by Harbury et al.).

ACKNOWLEDGEMENTS: I thank Janet Baker and Colin Stuart for the art work.

References

ACHDAN, A. and TURKANDI, T. (1982). Preliminary geologic map of the Kai (Tayandi and THai) quadrangle, Maluku (1:250,000). Geological Research and Development Centre, Indonesia.

AUDLEY-CHARLES, M. G. (1968). The Geology of Portuguese Timor. Mem. Geol. Soc. London 4, 1-76.

AUDLEY-CHARLES, M. G. (1978). Indonesian and Philippine Archipelagoes. In The Phanerozoic geology of the world II. The Mesozoic A. (ed. M. Moullade and A. E. M. Nairn), pp. 165-207, Elsevier, Amsterdam.

AUDLEY-CHARLES, M. G. (1983a). Comments on 'Analogous tectonic evolution of the Ordovician foredeeps, southern and central Appalachians'. Geology l l , 490-3.

AUDLEY-CHARLES, M. G. (1983b). Reconstruction of eastern Gondwanaland. Nature 306, 48-50.

AUDLEY-CHARLES, M. G. (1984). Cold Gondwana, warm Tethys and the Tibetan Lhasa block. Nature 310, 165-6.

AUDLEY-CHARLES, M. G. (1986a). Rates of Neogene and Quaternary tectonic movements in the southern Banda Arc based on micropalaeon- tology. J. Geol. Soc. London 143, 161-75.

AUDLEY-CHARLES, M. G. (1986b). Timor-Tanimbar Trough: the foreland basin of the evolving Banda orogen. In Foreland Basins. (ed. P. A. Allen and P. Homewood). Internat. Assoc. Sedimentolo- gists Spec. Pub. 8, 91-102.

AUDLEY-CHARLES, M. G. (1987). Dispersal of Gond- wanaland: relevance to the evolution of the angio- sperms. In Biogeography of the Malay Archi- pelago. (ed. T. C. Whitmore), Clarendon Press, Oxford, pp. 5-25.

AUDLEY-CHARLES, M. G., CARTER, D. J., BARBER, A. J., NORVICK, M. S., and TJOKROSAPOETRO, S. (1979). Reinterpretation of the geology of Seram: implications for the Banda Arcs and northern Australia. J. Geo. Soc. London 136,547-68.

AUDLEY-CHARLES, M. G., BALLANTYNE, P. D., and HALL, R. (1988). Mesozoic-Cenozoic rift-drift sequence of Asian fragments from Gondwana- land. Tectonophys. (In press).

BHATIA, M. R., THOMAS, M., and BOIRIE, J. M. (1984). Depositional framework and diagenesis of the Late Permian gas reservoirs of the Bonaparte basin. Austral. Petrol. Explor. Assoc. J. 24, 299-313.

BIRD, P. (1987). The Geology of the Permo-Triassic rocks of Kekneno, west Timor. Unpublished Ph.D. Thesis, University of London.

BowiN, C., et al. (1980). Arc-continent collision in Banda Sea region. Am. Assoc. Petrol. Geol. Bull. 64, 868-915.

CHAMALAUN, F. H. and WHITE, A. (1975). Electro- magnetic induction at Dili, Portuguese Timor. J. Geophy. 41,537-40.

CHAMALAUN, F. H., LOCKWOOD, K., and WHITE, A. (1976). The Bouguer gravity field and crustal structure of Timor. Tectonophys. 30, 241-59.

CHAMALAUN, F. H., GRADY, A. E., VON DER BORCIt, C. C., and HARTONO, H. M. S. (1981). The tectonic significance of Sumba. Bull. Geol. Res. & Dev. Centre, Bandung 5, 1-20.

COOK, S. (1986). Triassic sediments from east Kekneno, west Timor. Unpublished Ph.D. Thesis, University of London.

COOK, A. C., SMYTH, M., and Vos, R. G. (1985). Source potential of Upper Triassic fluvio-deltaic systems of the Exmouth Plateau. J. Austral. Petr. Explor. Assoc. 25,204-15.

CROSTELLA, A. and BARTER, T. (1980). Triassic-Jur- assic depositional history of the Dampier and Beagle sub-basins, northwest shelf of Australia. J. Austral. Petrol. Explor. Assoc. 20, 25-33.

Dow, D. B. and SUKAMTO, R. (1986). Western Irian Jaya: the end product of oblique plate con- vergence in the Late Tertiary--Reply. Tectono- phys. 121,348-50.

Evo lu t ion o f Tethys southern margin 99

FALVEY, D. A. and MUTTER, J. C. (1981). Regional plate tectonics and the evolution of Australia's passive continental margins. BMR J. Austral. Geol. Geophys. 6, 1-29.

GIANI, L. (1971). The geology of the Belu district of Indonesian Timor. Unpublished M.Phil. Thesis, University of London.

HAMILTON, W. (1979). Tectonics of the Indonesian region. US Geol. Surv. Prof. Pap. 1078, 345 pp.

JACOBSON, R. S., SHOR, G. G., KIECKHEFFER, R. M., and PURDY, G. M. (1978). Seismic refraction and reflection studies in the Timor-Aru Trough system and Australian continental shelf. Mere. Am. Assoc. Petrol. Geol. 29, 209-22.

KLOMPE, T. H. F. (1956). The structural importance of the Sula Spur (Indonesia). Pacific Science Con- gress, 8th Quezon City Philippines, 1955 Proceed- ings 2A, 869-89.

KUNDm, E. (1956). Geology and ophiolite problems of East Celebes. Koninkl. Nederlandsch Geol.- Mijnbouw Genoot Verh. Geol. 16,210-35.

LAWS, R. A. and KRAUS, G. P. (1974). The regional geology of the Bonaparte Gulf Timor Sea area. J. Austral. Petrol. Explor. Assoc. 14, 77-84.

MARGOLIS, S. V., KU, T. L., GLASBY, G. P., FEIN, C. D., and AUDLEY-CHARLES, M. G. (1978). Fossil manganese nodules from Timor: geochemical and radiochemical evidence for deep-sea origin. Chem. Geol. 21,185-98.

MCCAFFREY, R. and NABELEK, J. (1986). Seismological evidence for shallow thrusting north of the Timor Trough. Geophys. J. Roy. Astron. Soc. 85, 365-81.

MCCAFFREY, R., et al. (1984). Preliminary results of the 1982 microearthquake survey in Nusa Teng- gara, Timor, Indonesia. Bull. Geol. Res. & Dev. Centre, Indonesia 10, 1-9.

MCCAFFREY, R., MOLNAR, P., and ROECKER, S. (1985). Microearthquake seismicity and fault plane solu- tions related to arc-continent collision in the eastern Sunda Arc, Indonesia. J. Geophys. Res. 90, 4511-28.

METCALFE, I. (1988). Origin and assembly of south- east Asian continental terranes. This volume, p. 101.

O'BRIEN, C. A. E., GRAY, K. W., and GILLESPIE, I. (1961). The geological results of petroleum exploration in western Papua. Geol. Soc. Austral. J. 8, 1-133.

PmRAM, C. J. and PANGGABEAN, H. (1984). Rifting of the northern margin of the Australian continent and the origin of some microcontinents in eastern Indonesia. Tectonophys. 107,331-53.

POWELL, D. E. (1976). The geological evolution of the continental margin off northwest Australia. J. Austral. Petrol. Explor. Assoc. 16, 13-23.

PRICE, N. J. and AUDLEY-CHARLES, M. G. (1983). Plate rupture by hydraulic fracture resulting in overthrusting. Nature 306,572-5.

PRICE, N. J. and AUDLEY-CHARLES, M. G. (1987).

Tectonic collision processes after plate rupture. Tectonophys. 140, 121-9.

ROBINSON, P. L. (1973). Palaeoclimatology and continental drift. In Implications of continental drift to the Earth sciences. Vol. 1. (ed. D. H. Tarling, and S. K. Runcorn), pp. 451-76, Academic Press, London.

SCHLUTER, H. U. and FRITSCH, J. (1985). Geology and tectonics of the Banda Arc between Tanimbar island and Aru island. Geol. Jb. 30, 3-41.

~ENGOR, A. M. C. (1986). The dual nature of the Alpine-Himalayan system: progress, problems and prospects. Tectonophys. 127, 177-95.

SILVER, E. A., JOYODIWIRYO, Y., and MCCAFFREY, R. (1978). Gravity results and emplacement geometry of the Sulawesi ultramafic belt, Indonesia. Geology 6, 572-81.

SIMANDJUNTAK, T. W. (1986). Sedimentology and the tectonics of the collision complex of the east arm of Sulawesi, Indonesia. Unpublished Ph.D. Thesis, University of London.

SMART, J. and SENIOR, B. R. (1980). Jurassic-Creta- ceous basins of northern Australia. In The geology and geophysics of northeastern Australia. (ed. R. A. Henderson and P. J. Stephenson), pp. 3,15-28, Geological Society of Australia.

SMART, J., GRIMES, K. G., DOUTCH, H. F., and PIN CHIN, J. (1980). The Carpentaria and Karumba basins, north Queensland. Austr. BMR Geol. & Geophys. Bull. 202.

SMITH, R. B. (1983). Sedimentology and tectonics of a Miocene collision complex and overlying late orogenic clastic strata, Buton Island, eastern Indonesia. Unpublished Ph. D. Thesis, University of California, Santa Cruz.

SUKAMTO, R. and SIMANDJUNTAK, T. U. (1983). Tec- tonic relationship between geological provinces of western Sulawesi, eastern Sulawesi and Bang- gai-Sula in the light of sedimentological aspects. Bull. Geol. Res. & Dev. Centre, Indonesia 7, 1-12.

SUKARDI and SUTRISNO (1981). Preliminary geological map of the Tanimbar Islands quadrangle, Maluku (1:250,000). Geological Research and Develop- ment Centre, Indonesia.

TJOKROSAPOETRO, S. and BUDHITRISNA, T. (1982). Geology and tectonics of the northern Banda Arc. Bull. Geol. Res. & Dev. Centre, Indonesia 6, 1-17.

TOLLMANN, A. and KRISTAN-TOLLMANN, E. (1985). Paleogeography of the European Tethys from Paleozoic to Mesozoic and the Triassic relations of the eastern part of Tethys and Panthalassa. In The Tethys. (ed. K. Nakazawa and J. M. Dick- ins), pp. 3-22, Tokai University Press, Tokyo.

VAN BEMMELEN, R. W. (1949). The Geology of Indonesia. Government Printing Office, The Hague.

VEENSTRA, E. (1985). Rift and drift in the Dampier sub-basin, a seismic and structural interpretation. J. Austral. Petrol. Explor. Assoc. 25, 177-89.

100 M. G. A u d l e y - C h a r l e s

VEEVERS, J. J. (1984). Phanerozoic Earth history of Australia. Clarendon Press, Oxford. (418 pp.)

VEEVERS, J. J. and HEIRTZLER, J. R. (1974). Tectonic and palaeogeographic synthesis of Leg 27. In Initial Rep. DSDP 27, pp. 1049-54.

VIND, E. W. and HARWOOD, C. R. (1965). Geophysi-

cal exploration in Torres Strait. Austr. Petrol. Explor. Assoc. J. 5, 188-90.

WESTERMANN, G. E. G., SAXO, T., and SI<WARI~O, S. K. (1978). Brief report on the Jurassic biostratigra- phy of the Sula Islands, Indonesia. Newsl. Stratigr. 7 (2), 96-101.

M. G. AUDLEY-CHARLES, Department of Geological Sciences, University College London, Gower Street, London WC1E 6BT, UK.

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