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ignimbritic volcanism continued into the Early Permian. During the Late Carboniferous - Early Permian, there was a change from an oblique convergent margin to a dextral strike-slip margin (Murray & others, 1987; see also Korsch, 1982). Murray and others (1987) proposed that this change was the result of the arrival at the trench of a midocean ridge - transform fault system and subsequent triple junction migration. The Barnard Basin, which includes the Manning Group and sediments of the Nambucca Block, formed in the Early Permian through rifting of the Devonian-Carboniferous convergent margin assemblage (Leitch, 1988). As such, it may represent a marginal or back-arc basin (Scheibner, 1973, 1976), behind a volcanic arc situated outboard of the present continental margin, which is represented by arc volcanics of the Gympie (Queensland) and Brook Street (New Zealand) terranes (Harrington, 1983). Extension in the Barnard Basin may have been sufficient to generate limited oceanic crust, as tholeiitic volcanics of ocean-floor affinity occur (Scheibner & Pearce, 1978; Asthana & Leitch, 1985; Leitch & Asthana, 1985; Leitch, 1988). A consequence of the transcurrent margin was the development of a large orocline in the Early Permian, which increased the overall width of the New England Province. Murray and others (1987) proposed that the change to a dextral transform margin and the subsequent oroclinal bending took place in the Late Carboniferous, approximately 300 Ma; they also suggested that oroclinal bending took place as a result of up to 500 km of dextral movement along their postulated Gogango-Baryulgil Fault Zone (Fig. 3). However, Korsch and Harrington (1985, 1987) argued that deformation and metamorphism of the Nambucca Block, and the deformation of Early Permian sediments in the Texas area in the northern part of the province, are related to the oroclinal bending, which must therefore have taken place in, or later than, the Early Permian. Korsch and Harrington (1987) considered that the controlling strike-slip fault for oroclinal bending was the Mooki Fault System and that movement took place on a crustal detachment on top of the old subduction zone (Fig. 3). Korsch and Harrington (1981) identified several major deformational episodes in the New England Province, three of which (D2, D3 and D4) occurred during the Permian; D2 and D3 in the Early Permian (c. 290 and 273 Ma) and D4 in the Late Permian (255- 250 Ma). In the Late Carboniferous - Early Permian, the New England Province was intruded by the S-type Hillgrove and Bundarra Plutonic Suites (Fig. 4). Rb-Sr whole rock isochrons of 312 ± 25 Ma (Hensel & others, 1985) and 289 ± 25 Ma (Flood & Shaw, 1977) for the Hillgrove Suite, and 287 ± 10 Ma (Hensel & others, 1985) for the Bundarra Suite probably reflect the age of magma generation (Kleeman, 1988). Kleeman gives the ages of emplacement for the Hillgrove and Bundarra Suites as 293-275 Ma (Cooper & others, 1963; Hensel, 1982; Kleeman, 1975) and 280-270 Ma (Shaw & Flood, 1982) respectively. Widespread, low-grade, intermediate pressure metamorphism which possibly occurred in the Early Permian (c. 280 Ma), is overprinted by a later (255-250 Ma) metamorphic event (Leitch & McDougall, 1979; Korsch, 1982). Low pressure, high-grade metamorphic complexes at Wongwibinda and Tia are associated with migmatites and plutons of the Hillgrove Suite (Korsch, 1982). The southern and western margins of the Province, which are defined by the Hunter- 30
• WARWICK KILOMETRES 0^20^40^60 0^10^20^30 MILES BRISBANE 27- 36 = NEW ENGLAND — FOLD BELT 4 35- 5 29 - - 26 -12 - 19 - 14 -15 -34 -30 25 r f^7 Aifi [OFFS HARBOUR •i/ 6 (la 28 2 20- 21 - 16 - 18 - 17 22 - 10 - - TAMWORTH• co WALCHA TRIASSIC GRANODIORITE 1,4,2‘c,1 V Tertiary Basalts Permian Volcanics Serpentinite 4' _ 9 )64 -31 PLUTONIC SUITES r LeucOadamellites 13 Bundarra Hillgrove Uncertain Figure 4.^Distribution of plutonic suites and volcanics in New England Province (from Shaw & Flood, 1981). 31
Page 1 and 2: BMR RECORD 1990/60 PAUEOGEOGRAPHY 1
Page 3 and 4: PERMIAN ENERGY & MINERAL RESOURCES^
Page 5 and 6: FOREWORD Palmogeographic maps are o
Page 7 and 8: were then used to determine the sed
Page 9 and 10: Oil); L.G. Elliott, P.L. Price, and
Page 11 and 12: sequences underlying parts of the S
Page 13 and 14: Eurydesma occurrences, suggesting t
Page 15 and 16: that the Lynningtonian stage embrac
Page 17 and 18: is constrained by the presence in p
Page 19 and 20: Permian igneous activity in the Per
Page 21 and 22: the late Artinskian and the basin w
Page 23 and 24: the Permian, however, the Permo-Car
Page 25 and 26: sea level; the only documented Perm
Page 27 and 28: southern Sydney Basin have been rel
Page 29 and 30: Connors-Auburn Volcanic Arc (Day &
Page 31 and 32: NEW ENGLAND OROGEN Yarrol Province
Page 33: ^ 300 Ma CURTIS ISLAND TERRANE 302
Page 37 and 38: existence of the fault. DISCUSSION
Page 39 and 40: Figure 5. Australia's position in G
Page 41 and 42: would alone occupy an entire volume
Page 43 and 44: the map), perhaps being joined by c
Page 45 and 46: Extensive bodies of marine water oc
Page 47 and 48: e attributed to the higher sea leve
Page 49 and 50: The marine region of eastern New En
Page 51 and 52: equivalents of the Bonaparte succes
Page 53 and 54: Figure 7. Eastern Australian palmog
Page 55 and 56: ocks at all of Permian 4 age, could
Page 57 and 58: others, 1985). Granitic intrusion a
Page 59 and 60: history of upper delta plain facies
Page 61 and 62: Basins were sourced from the underl
Page 63 and 64: structure in this area, ideally sui
Page 65 and 66: The Pedirka Basin's petroleum prosp
Page 67 and 68: side of the outcropping portion of
Page 69 and 70: Murray Infra-basins and Oaklands Ba
Page 71 and 72: as they were infilled; a hiatus occ
Page 73 and 74: Permian Alum Mountain Volcanics, in
Page 75 and 76: to the end of the period (Fig. 8).
Page 77 and 78: SELECTED BIBLIOGRAPHY ALLCHURCH, P.
Page 79 and 80: BANKS, M.R., & AHMAD, N., 1962 - Th
Page 81 and 82: BLACK, L.P., BLAKE, D.H., & OLATUNJ
Page 83 and 84: Resources, Australia, Record 1990/6
Page 85 and 86:
BROWN LOW, J.W., 1982a - A time-spa
Page 87 and 88:
E.L. (Editors) - Geology and minera
Page 89 and 90:
in New England, New South Wales. Jo
Page 91 and 92:
Metallogeny and tectonic developmen
Page 93 and 94:
Lochinvar Formation of the Sydney B
Page 95 and 96:
EXON, N.F., 1974 - The geological e
Page 97 and 98:
GSQ Mundubbera 5 & 6, Taroom Trough
Page 99 and 100:
GULSON, B.L., DIESSEL, C.F.K., MASO
Page 101 and 102:
HAWKINS, P.J., 1976 - Facies analys
Page 103 and 104:
HOLCOMBE, R.J., LITTLE, T.A., GIBSO
Page 105 and 106:
JONES, P.J., 1988 - Comments on som
Page 107 and 108:
to basin development across Phanero
Page 109 and 110:
LE MAITRE, R.W., 1975 - Volcanic ro
Page 111 and 112:
MALONE, E.J., JENSEN, A.R., GREGORY
Page 113 and 114:
McPHIE, J., 1982 - The Coombadjha V
Page 115 and 116:
MORY, A.J., 1988 - Regional geology
Page 117 and 118:
OLGERS, F., WEBB, A.W., SMIT, J.A.J
Page 119 and 120:
Geological Survey of New South Wale
Page 121 and 122:
Bonaparte Gulf Basin 1963-71. Burea
Page 123 and 124:
Basin, central Queensland. Geologic
Page 125 and 126:
TINGATE, P.R., ANDREW, J.W., DUDDY,
Page 127 and 128:
VOISEY, A.H., & PACKHAM, G.H., 1969
Page 129 and 130:
WILFORD, G.E., 1983 - Phanerozoic p
Page 131:
ENVIRONMENT SYMBOLS ON PERMIAN INTE
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