摘要:

Recent mineral exploration in the McArthur River District, Northern Territory, has found new areas of base‐metal mineralization and has resulted in a reinterpretation of the geological setting of the previously discovered mineral deposits. The geology along the eastern margin of the H.Y.C. sub‐basin has been revised. The Cooley Dolomite Member of the Barney Creek Formation is interpreted as a talus‐slope breccia lying adjacent to a syndepositionally uplifted fault block (Western Fault Block) of lower McArthur Group sediments. The Western Fault Block was the source of the majority of the fragments in breccia horizons in the H.Y.C. sub‐basin and its uplift played an important role in the development of the sub‐basin. Within the Western Fault Block, the sequence hosting the Cooley II copper mineralization is the Mara Dolomite Member of the Emmerugga Dolomite, and not the Cooley Dolomite Member of the Barney Creek Formation as previously thought. New mineral discoveries include the substantial extension of the Coxco deposit, a coarse‐grained zinc‐lead stratabound deposit showing affinities with the Mississippi Valley‐type deposits; and an area of stratiform fine‐grained zinc‐lead mineralization in the Emu Plains sub‐basin of the Bulburra Depression.

ISSN:0016-7614    

DOI:10.1080/00167617708728996

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The Merrions Tuff is the structural‐stratigraphic marker of the flysch‐like fill of the Hill End Trough, a Siluro‐Devonian basin lying in central‐western New South Wales and bounded to the east and west by coeval, linear, meridional, shoalwater accumulations of limestones and volcanics. The Merrions Tuff is grossly tabular in form and consists of sheet‐like to lobate horizons of dacitic lavas and volcaniclastics. Internal vertical and lateral heterogeneities allow subdivision into members. Although some members are regionally extensive, others are not, so leading to a complex internal stratigraphy. Identification of regionally extensive time planes and analysis of the time‐stratigraphy shows that the base of the Merrions Tuff is diachronous. Although mesoscopic sedimentary structures such as sole structures are rare or not exposed, analysis of the parameters (spatial distribution of members, variation of and within members of their shape, thickness, grainsize, sand‐to‐shale ratios, numbers of sedimentation units, and distribution of vitriclasts), demonstrates that the Merrions Tuff was not derived from a single source and a single eruptive phase, but from several sources which were variously active at different times. Furthermore, through time there appears to have been a shift in the direction of dominant influx of basin fill, from the west through to the south, to the southeast and finally the east. Depositional patterns were controlled by a changing basin‐floor topography which was particularly influenced by the emplacement of the very thick member B lava. The effect of this flow was to displace the northwesterly‐trending basin axis existing at the beginning of the history of the Merrions Tuff to the east.

ISSN:0016-7614    

DOI:10.1080/00167617708728997

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The bedrock topography of the Botany Basin has been determined from seismic‐sparker records made in Botany Bay and Bate Bay, and from seismic‐refraction and gravity measurements on the Kurnell Peninsula. Supplementary information has been obtained from boreholes both on land and in the sea.

ISSN:0016-7614    

DOI:10.1080/00167617708728998

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Isotopic compositions of sulphur, carbon, and oxygen have been determined for constituents from a total of 103 samples of sedimentary rocks, mafic and ultramafic igneous rocks, nickel ores, and gold ores from the Archaean Yilgarn Block.

ISSN:0016-7614    

DOI:10.1080/00167617708728999

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

ISSN:0016-7614    

DOI:10.1080/00167617708729000

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

ISSN:0016-7614    

DOI:10.1080/00167617708729001

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Major‐ and trace‐element chemistry (including rare‐earth elements), total‐rock Rb‐Sr and U‐Pb and zircon U‐Pb data are used in an attempt to distinguish between two essentially coeval, felsic volcanic suites: the predominantly submarine Woodlawn suite which is associated with massive Cu‐Pb‐Zn sulphide mineralization and the terrestrial Mt Painter suite, with minor vein‐type mineralization. The Woodlawn samples are the unmineralized equivalents of the volcanics in the immediate ore environment.

ISSN:0016-7614    

DOI:10.1080/00167617708729002

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A map is presented based on all known Australian heat‐flow estimates, including five new ones. A second map, based on the first, also is presented, but excludes any determinations judged for any reason to be unreliable. The data show that heat flow over large areas of the continent is effectively uniform to within 0.5 heat flow units (i.e.to within 20 mW m‐2), with perhaps three major regional heat‐flow provinces being defined in western, central, and eastern Australia.

ISSN:0016-7614    

DOI:10.1080/00167617708729003

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Thirty K‐Ar dates on Cainozoic volcanic rocks lying at the north end of the Bowen Basin suggest that several episodes of volcanism took place at major structural weaknesses. The oldest volcanism (ca54 m.y.) was located outside the basin structure. The main volcanism (Nebo and East Clermont Provinces) extended from early Oligocene (34–35 m.y.) to mid‐Cainozoic time (21–22 m.y.?). Isolated Pliocene activity is tentatively suggested by dates on Mt St Martin (ca3 m.y.).

ISSN:0016-7614    

DOI:10.1080/00167617708729004

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Fission‐track dating has been applied for the first time to detrital mineral grains in sedimentary rocks. Unfossiliferous sandstones associated with Cambrian greenstones near Tatong, Victoria contain detrital zircon grains with an average age of 427 ± 20 m.y. This date provides a maximum age for the sandstones, so that they are younger than the Cambrian rocks, and have been tectonically juxtaposed. Radiometric dates for the eastern highlands of Victoria range from 390 to 460 m.y., and this mixed granitic‐metamorphic terrain may be the source for the zircons dated.

ISSN:0016-7614    

DOI:10.1080/00167617708729005

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor