Proterozoic

Prior to the Great Oxygenation Event (GOE) there was little oxygen in the atmosphere. Oxygenation of the atmosphere occurred in two steps, at the beginning and end of the Proterozoic eon (Frei, et al., 2013). In the GOE the surface oceans began to become oxygenated (Holland, 2006). The Second stage of oxygenation is known as the Neoproterozoic Oxygenation Event (NOE) and occurred after the 650-635Ma in the Marinoan glaciation (Sahoo, et al., 2012) (Feulner & Kienert, 2014). The NOE is thought to represent either further oxygenation (Holland, 2009) or deep ocean oxygenation (Canfield, 1998). This event is marked by resurgence in Banded Iron Formation (BIF) deposits which mark this second marine oxidation (Ilyin, 2009) (Frei, et al., 2009). The Marinoan and the Sturtian glaciations were two…

This image was source from en.wikipedia.org The crust of the continent is made principally of Archaean, Proterozoic and some Palaeozoic rocks and gneisses. A thin layer that is mostly Phanerozoic sedimentary basins covers a significant part of the Australian landmass; these are about 7km think. These thus are at present experiencing erosion by a mixture of aeolian and fluvial actions. The Australia continent has three major continental blocks: these include the Yilgarn Craton being the oldest…

Toward north is a reverse type fault bearing Pleistocene gravel across folded Proterozoic deposit is revealed near Terowie (Love et al., 1995, p. 270). Also confirmed on the north-eastern piedmont of the Flinders Ranges is severe folding of Miocene silcrete and related faulting, furthermore, and in slight magnitude, within the highland (Coats et al, 1969). On the northern Flinders ranges the east-plunging Mt Babbage thrust has conveyed Mesoproterozoic rock across Late Pleistocene and Holocene…

They are both aquatic as well as photosynthetic, simply meaning that they live in water and produce their own food. They are usually unicellular and reproduce by binary fission. They also often grow in colonies. The presence of phycobiliproteins, “water-soluble photosynthetic membrane proteins that covalently bind with phycobilins (photosynthetic pigments)” - McGraw-Hill Dictionary of Scientific & Technical Terms, are responsible for the blue-green colouring. Cyanobacteria are responsible for…

Bacteria had been in existence for billions of years however, 1.6bya during the Proterozoic era, we suddenly find the emergence of complex eukaryotic cells. All eukaryote cells share one common ancestor which emerged just once in 4 billion years of life on earth and all plants, protists, algae, animals and fungi are constituted by these cells. The cellular structure of bacteria and eukaryotes are so different there is no evidence to support the ‘directional’ evolution of eukaryotes from…

The Cambrian Period was an era filled with a massive explosion of a variety of animals and ecosystems. It was a time where super continent Pannotia no longer existed. During this time period, North America remained above water and was eroded by running water. North American was also on the equator which meant warm climate. The continents were oriented very differently, the east coast of North America faced the south. Activities such as transgression of the sea, and carbonate deposition went on…

optimal levels for these new animals to grow and thrive properly. This hypothesis is still under research because data on the salinity of the oceans is not accurate. Environmental, oxygen levels The main cause of the Cambrian explosion that has been researched and studied the most is the rise in levels of oxygen. Citations 1. Pagès A, Schmid S, Edwards D, Barnes S, He N, Grice K. 2016 A molecular and isotopic study of palaeoenvironmental conditions thorugh the middle Cambrian in the…

Phanerozoic? Name one important evolutionary event in each of those eras. Paleozoic The big incident of this era is the Cambrian explosion that happened 540 million years ago. Mesozoic Angiosperms were diversified during this era Cenozoic Mammals increase in size 2. Define/explain the following terms: Ediacaran, diagenesis, stromatolite, permineralized,…

1991). The Homestake formation is an iron and magnesium rich carbonate (Rye, Doe, and Delevaux 1974). The magnesium rich mineral is sideroplesite (magnesium sericite) (Norton 1971). There is also grunerite and cummingtonite found in the Homestake Formation (Morelli et al. 2010). The gold is hosted within a quartz veined sulfide rich segments of a carbonate iron formation, which are early Proterozoic in age (Caddey et al. 1991). The sulfide minerals that are associated with the gold are…

Isa deposit occurred in an intracontinental rift to passive margin environment with complicated history (Hutton et al. 2012). This rift environment produced the fluid source and fluid pathways. There are also orebodies deposition which occurred due to sedimentation but it appeared late in extensional cycle. It is found that the age of mineralization of Mt. Isa is approximately 1870 million years old (Forrestal, 1990). During that period, the oldest and nominated basement was disfigured and…