The Proterozoic Kalkadoon and Ewen Batholiths, Mount Isa Inlier, Queensland: source, chemistry, age, and metamorphism
The Proterozoic I-type Kalkadoon and Ewen Batholiths and their comagmatic extrusive equivalents, the Leichhardt suite, form an association covering at least 5000 km2 in the central part of the Mount Isa Inlier. U-Pb zircon data and some Rb-Sr total rock data show that these rocks crystallised from melts emplaced between 1840 and 1870 m.y. ago and are the oldest dated igneous rocks in the Inlier. Chemically and isotopically, these granites are relatively uniform and, compared with most other Mount Isa granites , they have higher Sr and Al2O3 contents, and lower TiO2 , Zr, Nb, and Th contents . These chemical characteristics appear to be restricted to felsic igneous rocks known to be older than 1800 m .y. and may be useful in identifying the older felsic melts of the Mount Isa Inlier. The source for the rocks of the Kalkadoon- Ewen- Leichhardt association is estimated to have had an SiO2 content of 55-60 per cent. Relative to other large Palaeozoic and Mesozoic I-type batholiths elsewhere, this Mount Isa association is enriched in K20, Rb, Th, U, La, Ce, Zr, and Nb, and depleted in CaO, MgO, Ni, and Cr. The least isotopically disturbed granites of the association have relatively low initial 87Sr/86Sr ratios (about 0.704), which implies that the age of the source for these melts was not much older than the age of their emplacement. As chemically and isotopically similar granites occur in most Proterozoic areas of Northern Australia, it is inferred that during the period 1900-2100 m.y. a significant mantle differentiation event took place, during which large volumes of material were accreted to the base of the crust in these areas. Post-emplacement metamorphism and deformation , which have a maximum age of 1640 m.y. , caused significant textural and mineralogical changes in the Kalkadoon Batholith, but had a lesser effect on the Ewen Batholith . Igneous textures are commonly preserved in the Ewen Batholith, but the Kalkadoon Batholith, which has been metamorphosed from lower greenschist to upper amphibolite grade, shows significant isotopic disturbances.
Simple
Identification info
- Date (Publication)
- 1983-01-01T00:00:00
- Citation identifier
- Geoscience Australia Persistent Identifier/https://pid.geoscience.gov.au/dataset/ga/81133
- Cited responsible party
-
Role Organisation / Individual Name Details Publisher Bureau of Mineral Resources, Geology and Geophysics
Canberra Author Wyborn, L.A.I
1 Author Page, R.W.
2
- Name
-
BMR Journal of Australian Geology and Geophysics
- Issue identification
-
8:1:53-69
- Point of contact
-
Role Organisation / Individual Name Details Custodian Corp
Owner Commonwealth of Australia (Geoscience Australia)
Custodian Commonwealth of Australia (Geoscience Australia)
Voice
- Topic category
-
- Geoscientific information
Extent
))
- Maintenance and update frequency
- Unknown
Resource format
- Title
-
Product data repository: Various Formats
- Website
-
Data Store directory containing the digital product files
Data Store directory containing one or more files, possibly in a variety of formats, accessible to Geoscience Australia staff only for internal purposes
- Keywords
-
-
GA Publication
-
Journal
-
- Keywords
-
-
QLD
-
- Australian and New Zealand Standard Research Classification (ANZSRC)
-
-
Earth Sciences
-
- Keywords
-
-
Published_External
-
Resource constraints
- Title
-
Creative Commons Attribution 4.0 International Licence
- Alternate title
-
CC-BY
- Edition
-
4.0
- Access constraints
- License
- Use constraints
- License
Resource constraints
- Title
-
Australian Government Security ClassificationSystem
- Edition date
- 2018-11-01T00:00:00
- Classification
- Unclassified
- Language
- English
- Character encoding
- UTF8
Distribution Information
- Distributor contact
-
Role Organisation / Individual Name Details Distributor Commonwealth of Australia (Geoscience Australia)
Voice
- OnLine resource
-
Journal article (pdf)
Journal article (pdf)
- Distribution format
-
-
pdf
-
Resource lineage
- Statement
-
Unknown
- Hierarchy level
- Non geographic dataset
- Other
-
GA Publication
- Description
-
Source data not available.
Metadata constraints
- Title
-
Australian Government Security ClassificationSystem
- Edition date
- 2018-11-01T00:00:00
- Classification
- Unclassified
Metadata
- Metadata identifier
-
urn:uuid/fae9173a-704a-71e4-e044-00144fdd4fa6
- Title
-
GeoNetwork UUID
- Language
- English
- Character encoding
- UTF8
- Contact
-
Role Organisation / Individual Name Details Point of contact Commonwealth of Australia (Geoscience Australia)
Voice
Type of resource
- Resource scope
- Document
- Name
-
AGSO BMR Journal
Alternative metadata reference
- Title
-
Geoscience Australia - short identifier for metadata record with
uuid
- Citation identifier
- eCatId/81133
- Date info (Revision)
- 2018-04-20T06:10:04
- Date info (Creation)
- 2014-06-03T00:00:00
Metadata standard
- Title
-
AU/NZS ISO 19115-1:2014
Metadata standard
- Title
-
ISO 19115-1:2014
Metadata standard
- Title
-
ISO 19115-3
- Title
-
Geoscience Australia Community Metadata Profile of ISO 19115-1:2014
- Edition
-
Version 2.0, September 2018
- Citation identifier
- https://pid.geoscience.gov.au/dataset/ga/122551