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Late glacial episodes in Gondwanaland reflected in transgressive-regressive depositional sequences in Euramerica

J J VEEVERS 1 C McA POWELL 1 J^ustra^n ^esearc^ Group, School of Sciences, Macquarie University, New South Wales, 2109,

ABSTRACT INTRODUCTION which straddled the equator so that its wide- spread shallow-marine to paralic sequences The Late Paleozoic glaciation of Gondwan- New information concerning (a) the age and contain rich faunas, including those of the short- aland comprised two short episodes, in the extent of Late Paleozoic ice centers in Gond- ranging ammonoids, fusulinid foraminifera, and Famennian (I) and Visean (II) confined to wanaland (Hambrey and Harland, 1981; Caputo conodonts (Ross and Ross, 1985a). Except Brazil and adjacent northwest , and a and Crowell, 1985; Martinez Diaz, 1985) and along its Paleo-Tethyan and Paleo-Pacific ma- long episode that started in the Namurian (b) the age of depositional transgressive-regres- rine margins, the Gondwanaland sequences are (IIIA) of eastern Australia and Bolivia/ sive sequences in Euramerica (Johnson and nonmarine, and only the ubiquitous microflora Argentina, expanded to cover much of others, 1985; Ross and Ross, 1985a, 1985b; affords the means for regional correlation and a Gondwanaland in the Stephanian/Asselian Heckel, 1986; Saunders and Ramsbottom, less secure inter-regional correlation (Anderson, (IIIB), and collapsed in the early Sakmarian 1986) confirms Wanless and Shepard's (1936) 1981; Truswell, 1980). Nevertheless, the age of (IIIC). Dropstones in eastern Australia indi- hypothesis that Euramerican cyclothems were the microfloras can be linked to that of the Eur- cate that small ice centers lingered to the controlled largely by sea-level fluctuations re- american faunas by way of the rare Euramerican Kazanian. Across the belt of low latitudes lated to climatic variation during the Gondwana- taxa in the cold-water faunas of the Gondwana- north of Gondwanaland, short-ranging fossils land glaciation. Of the three episodes of the Late land margins, as, for example, by the occurrence in widespread shallow-marine and paralic Paleozoic glaciation, episode I (Famennian) was of the early Namurian ammonoid Cravenoceras deposits indicate synchronous deposition of localized to Brazil and adjacent northwest in the eastern Australian fauna of the Levipus- transgressive-regressive sequences in differ- Africa, and II (Visean) to Brazil; only episode III tula levis zone, dominated by the longer-ranging ent parts of Euramerica. These sequences (Namurian to Sakmarian) extended across brachiopods and bivalves. Correlation within correlate with glacial events in Gondwana- Gondwanaland. All three glacial episodes cor- Gondwanaland at the transition from the Car- land at three levels: (a) four major regressions relate with transgressive-regressive sea-level events boniferous to the is uncertain because in Euramerica, in the Famennian (1), Visean in Euramerica, and the extensive episode III of poor age-calibration between the marine fau- (2), Namurian (3), Stephanian (4), and the correlates with cyclothemic deposition in nas and nonmarine microfloras; here we follow Tastubian transgression that preceded the Euramerica. Wanless and Shepard (1936) indi- the palynostratigraphic scheme that places the Sterlitamakian regression (S), also recorded cated the possibility of a general correlation of -Permian boundary between Units in Gondwanaland, correlate with glacial epi- the interval of glaciation with that of cyclo- II and III of Western Australia and Stages 2 and sodes I, II, and IIIA, mB, and mC; (b) the themic deposition, and Crowell (1978) nar- 3 of eastern Australia (Kemp and others, 1977; time-interval of cyclothemic deposition in rowed the correlation by showing that glaciation Balme, 1980), rather than at the base of Unit II Euramerica (Brigantian or latest Visean to lasted from the Visean to the lowermost or Stage 2, as advocated by Archbold (1982) Sterlitamakian) correlates with that of glacial Kazanian. Here we (1) refine this correlation by and Dickins (1984). Radiometric dates are con- episode III; and (c) the dominant period of establishing the precise start of glaciation of nected to the biostratigraphic scale after Harland the Euramerican cyclothems, as estimated episode III from eastern Australia as earliest and others (1982), in which the error of the Late from the Middle and Late Pennsylvanian Namurian, (2) show that the main regressions Paleozoic tie-points ranges from ±6 to ±11 m.y. are dominated by glacio-eustatic drawdown of deposits of the mid- of North Amer- The second difficulty is due to the onset of the sea level and the terminal transgression to ica, and of the thickest known Gondwana- main glaciation (episode III) being represented, glacio-eustatic rise of sea level, and (3) that the land glacigenic sediment (the earliest Permian except in a few places, by a mid-Carboniferous cyclic period of cyclothemic and glacial deposi- Lyons Group of Western Australia) is 0.4 (Namurian) stratigraphic gap or lacuna so that tion is the same and that it corresponds to the Ma, equivalent in turn to the long orbital- the onset of this episode has been overshadowed long period of orbital eccentricity in the Quater- eccentricity period of the Quaternary , by the later maximum glaciation of episode IIIB. nary and Miocene. and the dominant period of fluctuation of the In the analysis that follows, we scrutinize this late Miocene Antarctic ice cap. That it has taken 50 yr to apply a rigorous test lacuna in each Gondwanan , and point The three levels of correlations confirm of Wanless and Shepard's (1936) hypothesis is out evidence of coeval deformation and uplift, Wanless and Shepard's (1936) hypothesis due to two difficulties. The first arises from the which may have triggered the mid-Carbon- that the Late Paleozoic cyclothems are con- biostratigTaphical time-resolution of the Pennsyl- iferous glacial episode (Powell and Veevers, trolled largely by sea-level fluctuations re- vanian and Permian sequences in Gondwana- 1987). Because the lacuna is more readily inter- lated to the Gondwanaland glaciation. land being greatly inferior to that in Euramerica, pretable in Australia, we start with this region.

Geological Society of America Bulletin, v. 98, p. 475-487,6 figs., 3 tables, April 1987.

475

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including the Macleay area, a coeval decrease in TABLE 1. SOURCE OF INFORMATION GIVEN IN FIGURE 2 Figure 1. Late Paleozoic paleogeography the diversity of brachiopods (Roberts, 1981) and Topic Author of Gondwanaland, showing distribution of the disappearance of warm-water oolite confirm glacigenic sediment and inferred and postu- a fall in temperature. An indirect indication of TASMAN FOLD BELT

lated ice in glacial episodes I-m, areas of glaciation is provided by the marine Kullatine Crowell and Frakes (1971) orogenic uplift, and carbonate sediment. Formation. Crowell and Frakes (1971) "found Sydney, Werrie, Hambrey and Harland (1981) Tamwonh, Leitch (1974) Gondwanaland reconstruction from Powell no evidence of glaciation within the depositional Macleay Basins Martinez Diaz (1985, p. 13-56) and others (1980); polar wander path and pa- environment; nonetheless, the presence of stri- McMinn (1982) leolatitudes from Schmidt and others (1986). ated stones indicates that glaciers contributed Transgression-regression Dickins (1984) McMinn (1982) Compiled from information given in Figures debris to the basin." The striated stones lie with- Roberts (1985) 2-4 with, in addition, information on glaci- in the Namurian-Westphalian Levipustula levis Veevers (1984) genic sediment in Ethiopia from Hambrey zone, a few hundred metres above an occurrence Diversity Microflora Balme (1980) and Harland (1981) and Davidson and of the short-ranging ammonoid Cravenoceras Kemp and others (1977) McGregor (1976), and in Arabia from Mc- kullatinense, which indicates the earliest Namuri- Brachiopods Roberts (1981) Clure (1980) and Braakman and others an E zone (Campbell, 1962). The Kullatine Temperature Oolite Campbell and McKellar (1969) (1982). The 400 Ma map shows also the loca- Formation is an accumulation of mass-move- Metamorphism Cas and others (1976) tion of 1-11 and of places marking ment deposits (Lindsay, 1966), probably depos- Shaw and others (1982) changes of latitude: Quito (QO) representing ited rapidly, so that it is likely that the first Wyborn and Owen (1983) Piutonism Powell (1983) westernmost Gondwanaland; Zomba (ZA), appearance of ice at sea level in eastern Austra- Bathurst Granite (B) S. E. Shaw (1986, persona) commun.)

the centre; and Brisbane (BE), the eastern- lia was early Namurian, as confirmed by the Deformation and uplift Powell (1984) most part; all of these are given in Figure S. coeval decrease in brachiopod diversity. Galilee Basin G. D. Powis in Purcell (1984) The 255 Ma map shows also the location of Some authors (for example, Frakes, 1979), Veevers (1984) E. M. Truswell (1986, personal commun.) the transects given in Figures 2 through 4, have interpreted the glaciation as an alpine Drummond Basin Day and others (1983) including the abbreviations of localities. In precursor of a later ice sheet. From evidence of INTERIOR the 350 Ma map, WG = Witteberg Group, PE coeval uplift in eastern Australia, which was a Cooper Basin Veeveis (1984) = Pensacola Mountains; in the 325 Ma map, source of the piedmont and glacigenic Spion Adavale Basin Day and others (1983) W = Werrie Trough. Pedirka Basin Veevers (1984) Kop Conglomerate, and in the interior Amadeus Amadeus Transverse Zone (ATZ) Transverse Zone, and in view of its mid- Armstrong and Stewart (1975) Black and Gulson (1978) latitudinal position, Powell and Veevers (1987) Stewart (1971) Amadeus Basin Playford and others (1976) argue that this glaciation was triggered by wide- Young(1984) spread uplift along this part of the Paleo-Pacific Ngalia Basin Wells and Moss (1983) GONDWANALAND margin. Similar evidence along the South NORTHWEST American end of the Paleo-Pacific margin sug- Canning Basin Martinez Diaz (1985, p. 91-97) gests the growth of ice centers bigger than the Purcell (1984) Australia Bonaparte Gulf Basin Martinez Diaz (1985, p, 98-104) previously interpreted alpine ice caps. That the Roberts (1985) The long lacuna across the interior of Aus- ice did not extend to the west and northwest tralia shortens toward the Paleo-Pacific margin parts of Australia is indicated by the filling of on the east and the Paleo-Tethyan margin on the part of the lacuna by nonglacigenic sediment, after the Tastubian is provided by dropstones west (Figs. 1, 2; Table 1). On the east, in the including carbonate in the Bonaparte Gulf basin, that extend to the Kazanian in eastern Australia Tamworth fore-arc basin, a volcanogenic suc- which occupied low latitudes at the time and (Frakes, 1979). Transgressive-regressive marine cession containing oolitic and diverse could have provided a refuge for the highly events, derived from data given by Roberts faunas of warm-water aspect is overlain at the diverse yberti palynological assemblage (E. M. (1985) and Veevers (1984), include regressions Visean-Namurian boundary by the Werrie Truswell, 1985, personal commun.). in the Famennian, early Visean, early Namurian, Trough succession of volcanogenic rocks that By the end of the Stephanian (Palynological and late Westphalian, and a transgression, de- lack carbonate and diverse faunas and contain Stage 1), glacigenic sediment spread across most noted by the Eurydesma fauna, in the early instead glacigenic sediment. Direct evidence of of Australia and disappeared in the early part of Sakmarian or Tastubian (Dickins, 1984). glaciation is found in the Spion Kop Conglom- the Sakmarian (or Tastubian) during a marine We infer that ice started to accumulate by the erate at Tareela Creek (Hambrey and Harland, transgression marked by the Eurydesma fauna early Namurian along the uplifted Paleo-Pacific 1981), a piedmont deposit derived from an up- (Dickins, 1984). The thickest column of glaci- margin of eastern Australia. By the mid- lifted volcanic area to the west, with striated genic sediment in Gondwanaland, the Lyons Namurian, after the deposition of the youngest stones, and dropstones in laminated layers, Group of the Carnarvon basin, was deposited in (and nonglacigenic) sediment in the Ngalia basin derived from a wider plutonic and metamorphic this terminal episode IIIC (Fig. 1,275 Ma). The and during major uplift of the Amadeus Trans- area to the west, all bracketed by late Visean Lyons Group comprises 2,500 m of coastal- verse Zone, the ice center possibly extended to (Brigantian) marine sediment below and a plain to marine-shelf sediment with tillitic and the interior. To account for the long mid- 319 m.y.-old (late Namurian) tuff above glaciomarine layers (Hambrey and Harland, Carboniferous lacuna, we (Powell and Veevers, (Roberts and Engel, 1980; Martinez Diaz, 1985, 1981), all deposited during the earliest Permian 1987) postulate that the ice was frozen to bed- p. 16, 17). In a marine succession to the east, (Asselian and Tastubian). The only trace of ice rock (cold-based) so that sediment entrained in

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Figure 2. Correlation diagram of Australia, from the T as man Fold Belt in the east through the interior to the northwest. Vlid-Carboniferous lacuna enclosed by heavy lines in strati graphical columns on either side of the Mississippian/Pennsylvanian boundary (320 Ma). Symbols given in Figure 3. Time scale (Harland and others, 1982) on left, with palynological stages (Kemp and others, 1977; Balme, 1980; G. D. Powis in Purcell, 1984; upper limit of yberti uncertain, E. Truswell, 1985, personal commun., on right. Sources of information given in Table 1.

the ice was not deposited except along the ice until the Kazanian indicate that small accumula- the and was longer edge on the Paleo-Pacific margin. By the tions of ice lingered past the Sakmarian. still in the Prince Charles Mountains (Truswell, Stephanian, the ice spread finally to the west, 1980). In northern Victoria Land, the lacuna is became wet-based, and deposited sediment in - represented by Mississippian uplift, as shown by the newly formijd basins of the Innamincka the unroofing of end- granites (Grind- regime (Veevers, 1984). Dropstones deposited In Antarctica (Fig. 3; Table 2), the lacuna ley and Oliver, 1983). This uplift is of age sim- in eastern Australia in shallow-marine sediments encompasses almost the entire Carboniferous in ilar to Chat in adjacent Australia. Crowell (1978)

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Figure 2. (Continued).

argued that in the Pensacola Mountains, glacia- Namurian, but, as in Australia, was cold-based metamorphic dates (Sinha and Bagdasarian, tion may have started in the Mississippian be- and did not deposit on the platform until the ice 1977; Mehta, 1977; Gansser, 1964). Any defor- cause presumed Devonian sediment was still became wet-based in the Stephanian. mation in this area must have been slight soft when grooved by the overriding ice. From In the Indian sub-continent, the lacuna en- because the strata that enclose the lacuna are the Namurian to the end of the Carboniferous, compasses most of the Paleozoic (Hambrey and paraconformable. Glacigenic sediment succeeds the pole migrated across the Transantarctic Harland, 1981) except on the northern margin the lacuna and extends into the early Sakmarian Mountains. We infer that ice covered the Trans- (Punjab Himalaya), where the lacuna is re- (Tastubian). In Afghanistan (A in Fig. 1, antarctic area, as shown directly by glacigenic stricted to the late Namurian and Westphalian 325 Ma), an apparently continuous marine sediment in the Stephanian, and possibly started (Gupta, 1973; Dickins, 1984; Martinez Diaz, succession is reported by Montenat and others to grow in northern Victoria Land in the 1985, p. 153), and correlates with igneous and (1978) as containing glacigenic sediment with a

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ANTARCTICA PRINCE LAT N PEN.INDIA LAT SALT PUNJAB T IME CHARLES i TAM °s VL DAMODAR °S RANGE HIMALAYA G SCALE 1GNEOUSMOUNTAINS 90 15 70 0 N -(PCM) (DA) — - (SR) — — {PH) — -250- TATARIAN E 253 X 0 KAZANI AN 258- — :~i—r U -260- S KUNGURIAN + 263- T I I AFtTINSKIAN I I 268- M 1-270- SAKMARlAN E T

V V V V A -280- ASSEUAN * * A M * * * /<* *\ / * * \ 0 286 * * ^ R f-290 ^ V STEPHANIAN * * P i ICE / ICE. H 296H I -300 nr / m .••' C WEST- PHALIAN -310 315- + TT -320- —320 + -324 NAMURIAN 1 -330 333- A

-340 AFGHANISTAN VISEAN

352 rOURNAISIAN -360 n_n FAMENNIAN V 367- 1 ^370 FRASNIAN 374- rzi GIVETIAN 380- EIFELIAN 387- EMSIAN 394- PRAG 400 SIEGEN 401 LOCKH GEOINN 408

Figure 3. Correlation diagram of Antarctica and the Indian Subcontinent, and key to Figures 2-4. Sources of information given in Table 2.

change from warm- to cold-water fossils in the Brazil and possibly also to the Agades and Accra zalez, 1983) and in the Tarija Formation of ad- earliest Namurian, of the same age as and of areas of Africa (Fig. 4; Table 3); episode II jacent Bolivia (Martinez Diaz, 1985). Marine similar paleolatii:ude to the oldest glacigenic (Visean) is restricted to Brazil (Caputo and fossils indicate that the Las Salinas Formation is rocks of Australia. Crowell, 1985). within the Namurian-Westphalian Levipustula The next youngest glacigenic sediment, rep- levis zone, and the Tarija Formation and the -Africa resenting the start of episode III, is in the Las striated boulder pavement of the Hoyada Verde Salinas Formation of the Central Patagonian Formation lie immediately beneath the L. levis Glacial episode I (Famennian) is restricted to Basin and the Hoyada Verde Formation of the zone. Ilie overlap of the Mississippian plant fos- the Solimoes, Amazonas, and Parnaiba Basins of Calingasta-Uspallata Basin of Argentina (Gon- sil Archaeosigillaria conferia in the L. levis zone

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KEY FOR FIGURES 2,3, AND 4 TABLE 1. SOURCE OF INFORMATION GIVEN IN FIGURE 2

Topic Author

ANTARCTICA

marine detrital Transantarctic Mountains Kemp and others (1977) (TAM) Truswell (1980) A Vee vers (1976) North Victoria Land Grindley and Oliver (1983) P (NVL) Vetter and others (1983) "T~l marine carbonate L Prince Charles Mountains Truswell (1980)

INDIAN SUBCONTINENT

F Peninsular India Anderson (1981) Damodar Basin Balme (1980) Eurydesma fauna T Dickins (1984) Truswell (1980)

Salt Range Hambrey and Harland (1981) Truswell (1980) Wadia (1966) piedmont non marine deposit Afghanistan (A) Montenat and others (1978)

Punjab Himalaya Dickins (1984) Gupta (1973) Martinez Diaz (1985, p. 147-159) glacigenic

to 75°S in South America; by the Stephanian (episode IIIB), ice extended from the tropic in dropstone /\ ° South America and Africa/ Arabia to the pole in / \ w 1 01 Antarctica until retreat in the Tastubian. The , Cr *, UJ little ice that lingered to the Kazanian in eastern I E I 2 Australia lay about the pole. Warm-water car- coal bonate deposition was restricted to the tropical margins except when it expanded to 60°S in the Late Permian.

volcanogenic O Glacigenic Sediment. The three glacial epi- ÜJ sodes are I (Famennian) in Brazil and northwest < Africa and II (Visean) in Brazil, both restricted : o to this part of Gondwanaland, and III, which ZJ volcanics I- started in the Namurian (IIIA) in eastern Austra- cn o lia and South America; extended by the a. Stephanian (B) to all parts of Gondwanaland except northwest Africa; and ended (C) in the Plutonic / metamorphic Tastubian in southern Brazil, southern Africa, India, and Australia. Eastern Australia retained some ice until the Kazanian. Transgressive-Regressive Events. Regres- megakinks folds sions 1 to 4 are registered in the almost continu- S ous successions of the Paleo-Tethyan margin in North Africa and northwestern Australia and of the Paleo-Pacific margin in eastern Australia. The regressions correlate with glacial episodes I, of the Las Salinas Formation (Azcuy and others, Pre- in the early Mississippian following II, and the start (A) and maximum (B) of epi- 1981) suggests that all of these glacigenic sedi- Famennian-Tournaisian deformation; the El sode III. The Tastubian transgression, marked in ments were deposited in the lower or Namurian Raton Formation indicates uplift in the late Mis- Argentina, southern Africa, India, and Australia part of the range of this zone, as shown in sissippian during deformation and plutonic ac- by the Eurydesma fauna, correlates with the end Figure 4. The youngest glacigenic sediment tivity in the Pre-Andean and Paganzo regions. of episode III (C). The following regression 5 is recorded in South America is of Asselian to possibly due to post-glacial isostatic rebound. Sakmarian (Stage 3) age (Kemp, 1975) in the Summary Parana Basin. EURAMERICAN SEQUENCES In the Andean region, the only formations Paleolatitude. According to paleomagnetic deposited during the Late Devonian and Missis- measurements (Schmidt and others, 1986), epi- The late Paleozoic strata of Euramerica sippian lacuna are the Ambo Group of Peru and sodes I and II took place at mid-latitudes (Fig. 6) can be classified in five orders of the El Raton Formation of the Calingasta- (45°S-60°S) in Brazil and at 30°S in northwest allocyclic transgressive-regressive units (Busch Uspallata Basin of Argentina. Both are piedmont Africa (Fig. 5). Episode IIIA started at the low and Rollins, 1984). The first-order curve (Hal- deposits; the Ambo Group indicates uplift of the latitude of 30°S in eastern Australia, and at 50°S lam, 1977) indicates a highstand of the sea rela-

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Figure 4. Correlation diagram of South America and Africa. Symbols given in Figure 3. Range of L. levis zone (L) shown by arrows. Sources of information given in Table 3.

tive to the during the Devonian and m.y.-long cycle that started with a highstand in with an inferred decreased rate of volcanic activ- Tournaisian and then a gradual fall of the sea the to the Devonian. Fischer attrib- ity and hence of atmospheric CO2 concentra- during the rest of i:he Carboniferous, Permian, uted the Late Paleozoic lowstand to reduced tion, leading to a replacement of an Early and . Fischer (1984) interpreted the 150- plate activity expressed in continental thickening Paleozoic: greenhouse state by a Late Paleozoic m.y.-long lowstand as the second half of a 300- by the aggregation of the continents in Pangea, icehouse state. Ross and Ross (1985a) empha-

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A FRICA

Figure 4. (Continued).

sized the biogeographical and climatic effects of 1977) from shows the approxi- curves and given definitively in the fourth-order the junction of Gondwanaland and Euramerica mate age of regressions in the mid-Visean, mid- curves in which individual sequences have been during the Carboniferous, and their junction Carboniferous, and Sterlitimakian; the compa- correlated from North America to , the during the Permian with Angara to form rable curve for northwest Europe shows a long Devonian by Johnson and others (1985) and Pangea. Detail within this cycle is shown by the regression from the end of the Westphalian to the Carboniferous and Permian by Ross and higher-order curves. the end of the Early Permian. The age of the Ross (1985b), each of whom inferred the se- The second-order curve (Vail and others, main regressions is narrowed in the third-order quences to have resulted from eustatic sea-level

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TABLE 3. SOURCE OF INFORMATION GIVEN IN FIGURE 4 The fifth-order cycles or major cyclothems, bly infer that the glaciation began an unknown with a period of as much as 0.4 m.y., analyzed in time before ... deposition" of preserved sedi- Topic detail by Heckel (1986), start synchronously in mentary sections peripheral to glacial centers.

SOUTH AMERICA the Brigantian or latest Visean (335 Ma) at a The difference at the start probably reflects the

Andes Dalmayrac and others (1980) gross change in facies from dominantly carbo- initial growth in the Brigantian of ice at high Linares and others (1980) nate to cyclothemic alternations of siliciclastics altitude, leading to its appearance at sea level at McBride and others (1976) Ramos (1984) and carbonate. In North America, the inception the start of the Namurian, as the difference at the

Martinez Diaz (1985, p. 188-196) of cyclothemic deposition is marked by the base end reflects the final retreat in the Sterlitimakian of the Ste. Genevieve Limestone (Swann, 1964), of ice above sea level. Gonzalez (1983) in northwest Europe by the base of the Yore- Martinez Diaz (1985, p. 203-205) Paganzo Basin dales (Ramsbottom, 1973), and in the Donetz Dominant Period of Cyclic Frakes (1979) Basin of the Soviet Union by the base of Suite B, and Glacigenic Deposition Martinez Diaz (1985, p. 205-212) McBride and others (1976) just below the Visean/Serpukhovian boundary Truswell (1980) (Wagner and others, 1979). In northwestern Eu- Chaco-Paraw Basin Baltne (1980), Frakes (1979) By allowing for uncertainties of the numerical rope, the cyclothems terminate with the with- East Parana Basin Baime (1980), Dickins (1984) equivalence of the biostratigraphical ages and of Frakes (1979) drawal of the sea in the late Westphalian, but the ratios of the periods of the major, interme- Hambrey and Harland (1981) the North American mid-continent cyclothems diate, and minor cycles, Heckel (1986) esti- Solimoes, Amazonas, extend continuously to the top of the Chase Pamaiba Basins Caputo and Crowell (1985) mated the period of major cycles for part of the Group at the end of the Wolfcampian (Moore, Middle and Late Pennsylvanian of the mid- AFRICA 1958), equivalent to the Sakmarian/Artinskian continent outcrop belt as lying within the range Cape Fold Bell Halbich and others (1983) boundary (268 Ma). Cyclic deposition therefore 0.235 to 0.393 m.y. He noted that this range Basin Anderson (1981), Balme (1980), started at the change to the shorter period approaches the 0.413 m.y. Milankovitch eccen- Dickins (1984), Truswell (1980) fourth-order cycles, but continued past them tricity cycle. Cape Basin Martinez Diaz (1985, p. 167-174) into the Permian. Where closely analyzed in the The thickest recorded column of late Paleo- Late Pennsylvanian mid-continent outcrop belt, Congo Basin Hambrey and Harland (1981) zoic glacigenic sediment is the 2,500-m Early Truswell (1980) the major cyclothems or fifth-order cycles have Permian (Asselian-Tastubian) Lyons Group of Agadesarea Caputo and Crowell (1985) an estimated range of period of 0.235 to 0.393 Hambrey and Harland (1981) the Carnarvon Basin, Western Australia (Con- m.y. (Heckel, 1986). don, 1967; Hambrey and Harland, 1981; Ttndauf, Bechar-Abadla, Martinez Diaz (1985, p. 299-333) Illizi Basins Dickins, 1984; Chumatov, 1985). In the thickest

Meseta Piqué (1983) CORRELATION OF EURAMERICAN measured surface section, near Mt. Sandiman Homestead, Condon (1967, figs. 42,46,48, 50, Maurilanides Lecorche(1983) AND GONDWANALAND EVENTS 52,56) recorded a total of 40 glacigenic boulder Regressions and Glacial Episodes beds in the six constituent formations. With the changes. With periods from 1-4 m.y. or longer duration of the Asselian-Tastubian interval es- and a range extending before and after the Late Being global and synchronous, the four main timated from Harland and others (1982) as 10 Paleozoic glaciation, the fourth-order sequences regressions (1-4) and the terminal transgression- to 15 m.y., the mean period of the boulder beds themselves must be caused primarily by a factor regression 5 of Gondwanaland and Euramerica lies within the range 0.250 to 0.375 m.y. This is or factors other than glacio-eustasy. From the are inferred to be eustatic. Being synchronous effectively the same range as Heckel's (1986) for youngest to the oldest, the precisely dated re- with glacial episodes I, II, and the start (A), the mid-continent major cyclothems, and like- gressions are (5) iiterlitimakian (270 Ma), fol- maximum (B), and end (C) of episode III, the wise approaches the long 0.4- m.y. Milankovitch lowing the Tastubian transgression; (4) Stephani- regressions and terminal transgression are in- eccentricity cycle for the Quaternary ice sheets an (296-286 Mai, attended by low-diversity ferred further to be glacio-eustatic. of the Northern Hemisphere a.nd also for the late faunas and cooler siurface-water (Ross and Ross, Miocene carbonate record of the equatorial Pa- 1985a, 1985b); (3) mid-Carboniferous, within Cyclic Deposition and Glacial Episode m cific, which Moore and others (1982) associated the Namurian (330-320 Ma), attended by nu- with long-term fluctuations in the Antarctic ice merous faunal extinctions (Saunders and Rams- The interval of cyclic deposition matches that cap. bottom, 1986) and cooler surface-water (Ross of glacial episode III to within a few million In summary, the estimated period of the best and Ross, 1985a, 1985b); (2) earliest Visean years. Cyclic deposition started in the Brigantian known cyclothemic deposits in Euramerica and (350 Ma); and (1) Famennian (367-360 Ma). (335 Ma), and glacial eposide III started in the the thickest glacigenic sediment in Gondwana- In Gondwanaland, each of these regressions is earliest Namurian (333 Ma). Cyclic deposition land coincide within the range of0.235 to 0.393 registered also in Australia and North Africa, ended at the Sakmarian/Artinskian boundary m.y. The coincident period leads to the inference and, additionally, for the Tastubian transgres- (268 Ma), and glacial episode III ended at the that fluctuations in the Giondwanaland ice sion and regression 5, in South America, south- Tastubian/Sterlitimakian boundary (271 Ma). sheets, as represented by that of Western Austra- ern Africa, and India (Fig. 5). The differences in age of the start and end of lia during the Asselian-Tastubian, were the In Euramerica, the two long regressions, 3 glaciation and of cyclothemic deposition are cause of the eustatic sea-level fluctuations re- and 4, fall within a set of fourth-order cycles small but real, amounting to a whole stage at corded in the Euramerican cyclothems, as repre- with periods < 1 m.y., with 1- to 2-m.y. cycles in both start (Brigantian) and end (Sterlitimakian). sented by the Middle and Late Pennsylvanian between, and 2- to 4-m.y. cycles in the Early The differences are not unexpected. As pointed deposits of the mid-continenl. Furthermore, the Permian and in the Visean and older (Fig. 6). out by Crowell (1978, p. 1351), "we can proba- approach of the period of the glacigenic Lyons

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Figure 5. Time-distribution in Gondwanaland of glacigenic and carbonate deposition by paleolatitude (from Fig. 1) and by regions 1 through 11 (located on 400 Ma map of Fig. 1) set alongside the transgressive (T)-regressive (R) sea-level curve of Australia (from Fig. 2) marked with regressions 1 to 4 and transgression [with Eurydesma (E) fauna]-regression 5, from all of which is inferred the ice volume of Gondwanaland in glacial episodes I, II, IIIA, IIIB, and IIIC, followed by the negligible ice volume in eastern Australia indicated by dropstones (D). The position of the Lyons Group, with a cyclic period of glacial deposition of 0.4 m.y., is shown by the bar in region 10. NM in region 1 (North Africa) stands for nonmarine intervals during the main regressions.

Group to that of the long cycle of eccentricity in DISCUSSION inferred from glacigenic deposits in Brazil and the Milankovitch theory suggests that fluctua- adjacent Africa and is reflected in regression 1, tions in the Earth's eccentricity were the same Inferred fluctuations in the volume of ice on and also for the Visean episode II in Brazil, re- in the Early Permian as they were in the Gondwanaland are shown in Figure 5. A minor flected in regression 2. An intermediate volume Quaternary. volume for the Famennian glacial episode I is for the mid-Carboniferous episode IIIA is in-

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well as in Euramerica. The following regression 5 affected both Gondwanaland, possibly due to isostatic unloading of the wasted ice sheets, and Euramerica, due to independent cratonic uplift that followed the final welding of Angara to constitute Pangea. An earlier epeirogenic mo- tion, independent of, but synchronous with, eustatic sea-level changes contributed to the mid-Carboniferous regression 3, as shown by the cratonic low-angle unconformity that lies beneath the major depositicnal sequences of Australia (Innamincka sequence, Veevers, 1984), South America (Delta sequence, Soares and others, 1978), and North America (Ab- saroka sequence, Sloss, 1963). In other parts of the Earth, the lacuna, recording no sensible deformation before the resumption of deposi- tion, is attributable solely to eustatic changes of sea level. The local tectonic effects of uplift accompany- ing orogenesis possibly triggered the glacial epi- sodes I and II and the onset of IIIA (Powell and Veevers, 1987). Episodes I (Famennian) and II (Visean) are restricted to a region of middle lati- tudes (Brazil and northwest Africa) bordered by orogenic uplifts (Mauritanides and northern and central Andes). The onset of episode IIIA (Namurian) is likewise restricted to regions that bordered orogenic uplift; the glacigenic sediment in eastern Australia is enclosed within piedmont deposits (Spion Kop Conglomerate), and that of Argentina is of similar age to nearby piedmont deposits (El Raton Formation). Previous workers (for example, Frakes, 1979) have ac- knowledged the contribution of uplift to this epi- sode ("alpine glaciation"); we simply extend the likely area of uplift from a narrow alpine chain in eastern Australia to a wider fold-belt plateau that extended into the interior (Amadeus Trans- verse Zone). The positive correlation of episodes I, II, and IIIA with local uplift contrasts with their nega- tive correlation with high latitude. As shown in Figure 5, episodes I and II are confined to mid- latitudes, and IIIA extends from higher to mid- dle latitudes. Glaciation at the south pole, except Figure 6. The Ave orders or degrees of marine inundation in Euramerica, showing regres- possibly in southern Africa in the Visean sions 1 to 4 and ti.-ansgression-regression 5. First-order curve of Soviet Union from Hallam (Witteberg Group), is not recorded until the end (1977); second-order curve of North America from Vail and others (1977) and of northwest of the Westphalian, by which time glaciation Europe from Smith and others (1974) and Ramsbottom (1979); third-order curve of the Soviet had spread northward to the tropic. Only after Union (Sloss, 1972) and North America (Wise, 1974) augmented in the Devonian, with super- the collapse of the last ice sheets in the Early imposed fourth-order curve, by Johnson and others (1985); and fourth-order curve of North Permian was the ice confined to the pole. The American Carboniferous-Permian from Ross and Ross (1985b); interval of fifth-order or cyclic pole remained in eastern Australia during the deposition in Nort h America, as described in the text, with a bar indicating the Late Pennsyl- later Permian and Early Triassic before it wan- vanian mid-continent cyclothems analyzed by Heckel (1986) as having a period of 0.4 m.y. dered into the Pacific, but no sign of ice is known. Within the first-order plate-tectonic control of the Late Paleozoic configuration of ferred from deposits in South America, eastern nents, reflected in regression 4. The dwindling the continents and oceans with the closing of Australia, and possibly Antarctica and is re- volume for the Tastubian episode IIIC is infer- Paleo-Tel:hys by the junction of Gondwanaland flected in regression 3. A major volume for the red from the final deposits, mainly glaciomarine, and Euramerica (Crowell, 1978; Ross and Ross, Stephanian episode IIIB is inferred from wide- and reflected in a transgression over parts of the 1985a, 1985b) and the attendant reduced rate of spread deposits in all. of the Gondwanaland conti- hitherto nonmarine Gondwanaland platform, as (Fischer, 1984), uplift accompany-

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Condon, M. A., 1967, The geology of the Carnarvon Basin, Western Australia. Late palaeogeographies of southeastern Australia: Geological ing orogenesis provided a trigger for the accum- Part 2: Permian stratigraphy: Australia Bureau of Mineral Resources, Society of Australia Journal, v. 30, p. 353-373. ulation of ice during episodes I, II, and IIIA. Geology and Geophysics Bulletin, v. 77,191 p. 1984, Terminal fold-belt deformation: Relationship of mid-Carbonif- Crowell, J. C., 1978, Gondwanan glaciation, cyclothems, continental position- erous megakinks in the Tasman fold belt to coeval thrusts in cratonic ing, and climatic change: American Journal of Science, v. 278, Australia: Geology, v. 12, p. 546-549. p.1345-1372. Powell, C. McA., Johnson, B. D., and Veevers, J. J., 1980, A revised fit of east CONCLUSIONS Crowell, J. C., and Frakes, L. A., 1971, Late Palaeozoic glaciation of Australia: and west Gondwanaland: Tectonophysics, v. 63, p. 13-29. Geological Society of Australia Journal, v. 17, p. 115-155. Powell, C. McA., Cole, J. P., and Cudahy, T. J., 1985, Megakinking in the Dalmayrac, B., Laubacher, G., Marocco, R., Martinez, C., and Tornasi, P., Lachlan Fold Belt, Australia: Journal of Structural Geology, v. 7, The predominant cause of regressions 1-4 1980, La chaîne hercynienne d'Amérique du Sud: structure et evolution p. 281-300. d'un orogène intracratonique: Geologisches Rundschau, v. 69, p. 1-21. Powell, C. McA., and Veevers, J. J., 1987, Namurian uplift in Australia and was glacio-eustatic drawdown of sea level dur- Davidson, A., and McGregor, D. C., 1976, Palynomorphs indicating Permian South America triggered the main Gondwanan glaciation: Nature (in ing glacial episodes I, II, and IIIA and during the rocks in Ethiopia: Nature, v. 262, p. 371-373. press). Day, R. W., Whitaker, W. G., Murray, C. G., Wilson, I. H., and Grimes, K. G., Pureed, P. G., ed., 1984, The Canning Basin, W. 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B., eds., 1981, Earth's pre-Pleistocene glacial New South Wales, and the extension of the I-S line of the Siluro- record: Cambridge, England, Cambridge University Press, 1,004 p. Devonian granitoids: Geological Society of Australia Journal, v. 29, We thank J. C. Crowell, O. K. Davis, J. M. Harland, W. B., Cox, A. V., Llewellyn, P. G., Pickton, C.A.G., Smith, A. G., p. 41-48. and Walters, R., 1982, A : Cambridge, England, Sinha, A. K., and Bagdasarian, G. P., 1977, Potassium-argon dating of some Dickins, L. A. Frakes, A. Hallam, J. Roberts, Cambridge University Press, 131 p. magmatic and metamorphic rocks from Tethyan and Lesser zones of C. A. Ross, E. M. Truswell, and the reviewers, Heckel, P. H., 1986, Sea-level curve for Pennsylvanian eustatic marine Kumuan and Garhwal Indian Himalaya and its implication in the Him- transgressive-regressive depositional cycles along midcontinent outcrop alayan tectogenesis: Colloques International du Centre National de la N. Christie-Blick and M. de Wit, for valuable belt, North America: Geology, v. 14, p. 330-334. Recherche Scientifique, v. 268, p. 387-393. Johnson, J. G., Klapper, G., and Sandberg, C. A., 1985, Devonian eustatic Sloss, L. L., ] 963, Sequences in the cratonic interior of North America: Geolog- comments, and R. H. Flood and M.A.J. fluctuations in Euramerica: Geological Society of America Bulletin, ical Society of America Bulletin, v. 74, p. 93-114. Williams for discussions. Powell thanks A. J. v. 96, p. 567-587. 1972, Synchrony of Phanerozoic sedimentary-tectonic events of the Kemp, E. M., 1975, The palynology of late Palaeozoic glacial deposits of North American and the Russian Platform: International Geo- Amos and O. Lopez Gamundi for facilitating Gondwanaland, in Campbell, K.S.W., ed., Gondwana geology: Can- logical Congress, 24th, Montreal, Section 6, p. 24-32. berra, Australia, Australian National University Press, p. 397-413. Soares, P. C, Landim, P.M.B., and Fulfero, U. 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