LOCATION |
Map |
Show Map
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Address |
Brachina Gorge FLINDERS RANGES |
Locality |
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Accuracy |
H - high level confidence |
Council Area |
Land Not Within a Council Area (Flinders) |
Polygon Type |
S - parcel that has been split (because it has more than one heritage item on it |
DESCRIPTION |
Details (Known As) |
Impact Ejecta Horizon Late Precambrian Shales Geological Site, Ikara-Flinders Ranges National Park |
Registered Name |
Late Precambrian Shales |
Significance |
This site in Brachina Gorge is part of a solitary layer of shattered rock fragments that has been traced over a distance of 260km within folded 600 million year old Precambrian marine shales in the Flinders Ranges.
The very thin layer, averaging 10cm in thickness, contains gritty grains and pebbles of volcanic rock. This debris (known as impact ejecta) is the result of the collision of an asteroid or comet into the Gawler Range Volcanics, some 300 km to the west of the Flinders Ranges which created Lake Acraman (registered place 14454). This ancient ejecta blanket of known source can provide valuable information on the nature and effects of large terrestrial impacts and the Acraman impact is distinguished as the only major terrestrial impact structure with widely distributed coarse ejecta still preserved. (Adapted from HB Assessment File and Geological Monuments in South Australia, item FR.36)
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Subject Index |
Landscape area - Geological Site |
Class |
State |
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STATUS |
Status Code |
REG - Confirmed as a State Heritage Place in the SA Heritage Register |
Status Date |
04-MAR-1993 |
REFERENCE |
LGA |
Unincorporated SA |
State Heritage ID |
14453 |
Heritage Number |
76 |
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SECTION 16 INFORMATION |
Section 16 |
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PLAN PARCEL & TITLE |
As listed in the SA Heritage Register |
Plan Parcel & Title Information |
CR 6228/876 D93043 Q68 |