摘要:

Rocks of the Windmill Islands, Antarctica (Lat. 66°S, Long. 110°E) consist of a layered sequence of schists, gneisses, and migmatites (the Windmill Metamorphics) intruded by a charnockite (the Ardery Charnockite) and a porphyritic granite (the Ford Granite), and cut by two swarms of easterly‐trending dolerite dykes.

ISSN:0016-7614    

DOI:10.1080/00167617708728986

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A new compilation of Australian meteorite discoveries suggests that many meteorites remain to be discovered by field geologists and others, in outback areas of Australia.

ISSN:0016-7614    

DOI:10.1080/00167617708728987

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Micropalaeontological investigation of samples from Scott Reef No. 1 has revealed a thick Cainozoic carbonate sequence. Rich planktonic faunas have enabled the identification of Lower Miocene to Oligocene (N6 to P19) and Lower Eocene to Lower Palaeocene intervals (P6 to Pic). The remainder of the succession has been dated on benthonic evidence and spot age‐determinations on isolated planktonic occurrences. The palaeoenvironmental history of the Cainozoic sequence appearstobe regressive from a bathyal situation in the Palaeocene through indeterminate marine Eocene, bathyal to inner shelf Oligocene to Middle Miocene, to reefal conditions which have persisted from the Middle Miocene to the present day.

ISSN:0016-7614    

DOI:10.1080/00167617708728988

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Two factors limited the compilation of geological maps of the Australian continent during the nineteenth century, the problems of geological mapping over large areas and the fact that Australia was divided into a group of independent colonies. Only four such maps were compiled and published during this period and all others are mere copies of three of these four.

ISSN:0016-7614    

DOI:10.1080/00167617708728989

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

During a lake‐full phase at the end of the Pleistocene Period, lacustrine silts and aeolian sands were deposited around the eastern margins of Kow Swamp. These sediments have yielded the remains of a large population of early Australian man, retaining certain archaicHomo erectuscharacteristics.

ISSN:0016-7614    

DOI:10.1080/00167617708728990

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The stable magnetizations of the Tasmanian Dolerites are shown to fall into two distinct groups depending upon their directions and the geographical region of the dolerites. It has been suggested that this could be a result of significant age differences between the dolerites of these groups. A series of K‐Ar determinations indicates that there is no detectable systematic age differences and the average of the five bodies dated is 170.5±8.0 m.y. (not significantly different from previous K‐Ar dates from a single body). A re‐appraisal of the palaeomagnetic data, in the light of the distinct groupings of the directions, yields two significantly different pole positions‐ Lat 50.7°S, Long. 174.5°E (A9r, = 5.2°) and Lat. 47.7 °S, Long. 123.5° (A95= 9.5°)’. The former of these is in excellent agreement with pole positions from other Lower to Middle Jurassic rocks of Australia but the significance of the latter remains obscure.

ISSN:0016-7614    

DOI:10.1080/00167617708728991

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Important mineral assemblages of metapelite and quartzite of the Strathgordon area are phengite + chlorite + tourmaline + quartz and phengite + garnet + chlorite + tourmaline + quartz. Over a limited area the Si4+‐content of phengite does not vary significantly and is considered to depend only on thePTregime. The Si4+‐content of phengite coexisting with almandine‐grossular‐spessartine garnet and tourmaline indicate that the maximum metamorphism of the area occurred at 400±50°C and 3 ± 1kb.

ISSN:0016-7614    

DOI:10.1080/00167617708728992

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The southern part of the New England Geosyncline is divided by the Peel Fault into two major zones, termed the Tablelands Complex to the east and the Tamworth Belt to the west. Because of stratigraphical similarities the Hastings Block is correlated with the Tamworth Belt. Seven major lithostratigraphic associations are recognized in the Tablelands Complex. The Woolomin Association is a deepwater marine chert‐jasper‐basic volcanic‐dominated sequence in which sandstones are rare. The Sandon Association is a turbidite sequence in which minor chert, jasper, and basic volcanics are present. The Coffs Harbour Association is a deepwater marine turbidite sequence and is distinguished from the Sandon Association by the absence of chert, jasper, and basic volcanics. The Nambucca Association is also deepwater marine in nature and is dominated by diamictites deposited by mass movements. The Silverwood Association contains components of a volcanic arc, and the Dummy Creek Association consists of terrestrial to shallow‐water marine sediments deposited in rim synclines associated with the granitic intrusions. The above associations contain sandstones which are predominantly quartz‐poor lithic greywackes and these differ from the Beenleigh Association which contains continental shelf to deepwater marine deposits in which the sandstones are quartz‐rich. Recognition of the associations has been hindered by the intrusion of four granitic suites, metamorphism of the sediments under differing conditions of temperature and pressure, and fragmentation by several large‐scale faults into numerous blocks.

ISSN:0016-7614    

DOI:10.1080/00167617708728993

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Although the largest earthquake since European settlement in South Australia occurred near Beachport in the Southeast in 1897, the recorded activity since then, even with the establishment of the University of Adelaide Seismograph Network and the Bureau of Mineral Resources station at Bellfield in the Victorian Grampians, has been small.

ISSN:0016-7614    

DOI:10.1080/00167617708728994

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

ISSN:0016-7614    

DOI:10.1080/00167617708728985

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor