What are the major global events that occurred in the Proterozoic? 

What are the major global events that occurred in the Proterozoic?

Proterozoic is considered to be a geological eon that spans the time from the oxygen present in the atmosphere of the Earth before the rise of a complicated life on Earth.  One of the main changes that occurred in the Proterozoic was the advancement of modern-style plate tectonics and everything that accompanies that, including the mountain belts and broad extensive edges.  The most ancient stable craton created during Archean at 3 Ga, Southern Africa, where there was a discovery of the most seasoned thick and shallow-water sedimentary rocks well-maintained above the Archean craton.  Generally, be that as it may, the remainder of this cratonization occurred in the early Proterozoic.

 

What evidence is there that oxygen increased significantly in the Earth’s atmosphere in the Paleoproterozoic?

As the biotic system and Proterozoic tectonic became well-known, the Earth started to develop extensive biomass containing planktonic and benthic photosynthesizing the living organizing, including the prokaryotic.  The presence of an enough environment where the organisms can live in with more different forms to explore in a wide section of environment, made the oxygen amount release to the atmosphere rises.  However, before oxygen got increased in the atmosphere, the oxygen sinks mostly the sulphur and iron which had to be used fully.   It is evident that oxygen considered and it is known to be a by product in the process of photosynthesis.

 The air (oxygen) which is always free in the atmosphere rises significantly due to the biology reaction in the Proterozoic.  This critical change happened between the years 1.8 million and 2.3million years ago when oxygen started accumulating up in the atmosphere.  Oxygen amount increases after 2 Ga, showing that after the exhaustion of the chemical sink, more oxygen was produced accumulating in the Earth’s atmosphere.  Research indicates that the level of oxygen in the Earth’s atmosphere is about 15% in the atmospheric levels.

How do geologists know that the glaciation was widespread early in the Proterozoic? 

The presence of the snowball provided evidence for glaciation spread.  The hypothesis of snowball Earth was initially formulated to clarify topographical proof for the presence of glacier masses at tropical latitudes.  According to research, an ice-albedo criticism would bring about glacial ice quickly progressing to the equator once the glaciers reach 25°to 30°along the equator.  Following these lines, the existence of glacial deposits along the tropics recommends worldwide ice spread.  Also, widespread glaciation is evidence of its presence in several places around the world.  It contains subglacial tillite, which is a thick deposit covered by the marine carbonate.

 

 

 

What reasons are there for the Wopmay orogen being referred to as a “modern‑style” orogen? 

One of the reasons why Wopmay orogeny exhibited as modern style is because it has structure belts which are parallel to each other.  Secondly, it is wopmay the classic sedimentary series contained in the unconformity on the ended rift event and inactive clastic covered by the carbonates, then sinking of deposition of molasses and flysch.

 

 

What is Laurentia, and how did it form? What is its relationship to present-day North America? 

Development of Little crustal that blocks throughout the Proterozoic forms Laurentia.  North America relates to this as it contains the volcanic islands and the high metamorphosed rocks which experienced the collision.  They formed mountain ranges running from the north USA to Quebec.

 

How did the Grenville orogeny relate to the Proterozoic continent, Rodinia

Grenville orogeny correlates with Rodinia has it is the long-lived belt of the Mesoproterozoic mountain which relates with the supercontinent Rodinia assembly

 

Part b

What is meant by the phrase “the Cambrian explosion of life?

The term “Cambrian Explosion” is referred to as the unexpected presence in the recording creatures’ remnants, which are considered to be complicated with reduces skeletal remains.  It might signify the most crucial developmental occasion throughout the entire existence of life on Earth.

 

Discuss the major differences between the Cambrian marine community and the Ordovician marine community

The period of Cambrian begun during the evolution known as the Cambrian explosion.   A rapid increase in ocean life was experienced in this period that led to the awareness of other species such as invertebrates and the phyla.  On the other hand, in the Ordovician community, some changes in invertebrates had developed in their shelly fauna and the start of building reef in masses.  The extinction of the phyla species ended the Ordovician period.

How and when was Pangea formed? What were the climatic results of the formation of this supercontinent? 

Pangae was formed about 300 years a million years ago.  It is believed that plate tectonics which form the earth system dived and collided under each other at the convergent borders forming a supercontinent.  The formation of the supercontinent lowers the sea level.

 

 

 

 

Three mass extinctions took place during the Paleozoic. What possible explanations are there for each event? 

Massive extinction for species such as trilobites, fusulinids, and blastoids were experienced in this period.  It is believed that extinction for these species happened due to lower sea levels.