It consists of Diamictite
glacial deposits (TBI), wash out plain deposits (TB2) and followed by subaqueous Diamictite
In the younger rocks, they discovered diamictite
, a clay-rich sedimentary rock typically formed in glacial environments.
First, the Snowball model is based on stratigraphic analyses, which, to borrow Harland and Herod's (1975) phrase are 'sedimentologically unsophisticated" Old, and by now very shop-worn assumptions that poorly sorted diamictite facies must be continental tillites deposited below ice sheets, and any fine-grained, rhythmically laminated facies are glaciolacustrine varvites, can still be found in the Snowball literature (Hoffman et al.
Where present, primary and stromatolitic carbonates are separated from underlying diamictite units by unconformities or many tens and sometimes hundreds of metres of marine strata, thereby questioning any supposed immediate 'cap' relationship (e.
Melanic soils develop from a variety of parent materials (Van der Merwe 2000), including arkosic sandstone, siltstone, mudstone, shale, diamictite
, dolerite, basalt, notite, amphibolite, granite, gneiss, rhyodacite, and carbonates.
Lithofacies types and vertical profile models: an alternative approach to the description and environmental interpretation of glacial diamict and diamictite
Outcrop based identified lithofacies in Tobra Formation are; unstratified clast supported conglomerate (Gem), massive diamictite
facies (Gmm), stratified diamictite
facies (Gmm), massive sandstone facies (Sm) and massive mudstone facies (Fm).
Lithofacies types and vertical profile models; an alternative approach to the description and environmental interpretation of glacial diamict and diamictite
At this site, baseball-size cobbles got mixed with a slurry of fine silt and sand to form a rock called diamictite
2010) suggest a strong shift into icehouse conditions during the event and represent, beside coeval diamictites
in western peri-Gondwana, an evidence of an early Silurian glaciation.
The unconformably overlying Neoproterozoic to Cambrian Beardmore Group, composed by the Cobham and Goldie formations is comprised of a thick low grade metamorphic sequence of sandstones, slates, carbonates, diamictites
with minor intercalations of volcanic rocks (Goodge et al.
This remarkable gap in the regional fossil record is partially accounted for by a tectonically related 30 million year depositional hiatus, which began around 330 million years ago and was followed by a period of approximately 10 million years of deposition of the Dwyka Group (Karoo Supergroup) glacial diamictites