Search results
Results from the WOW.Com Content Network
The Triassic–Jurassic (Tr-J) extinction event (TJME), often called the end-Triassic extinction, marks the boundary between the Triassic and Jurassic periods, . It is one of five major extinction events , profoundly affecting life on land and in the oceans.
It is the time lapse between death and discovery. After death, decomposition occurs. Decomposition includes physical, chemical, and biological changes. [19] Below are some of the biochemical changes that happen during decomposition which can help estimate the time since death (keeping in mind that there is variation between species): [20]
The sky turning dark during the day was interpreted as a sign of the end times. The primary cause of the event is believed to have been a combination of smoke from forest fires, a thick fog, and cloud cover. [73] 1789 Pierre d'Ailly: The year 1789 would bring the coming of the Antichrist, according to this 14th-century cardinal. [74] 1792, 1794 ...
The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, [2] was a time interval during the Earth's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. [3]
The Neoproterozoic Oxygenation Event (NOE), also called the Second Great Oxidation Event, was a geologic time interval between around 850 and 540 million years ago during the Neoproterozoic era, which saw a very significant increase in oxygen levels in Earth's atmosphere and oceans. [1]
This would make the Hirnantian-Rhuddanian anoxia one of the longest-lasting anoxic events in geologic time. [17] Cyanobacteria blooms after the Hirnantian glaciation likely caused the Hirnantian-Rhuddanian global anoxic event, the main factor behind the second extinction pulse. The cause of the Hirnantian-Rhuddanian anoxic event is uncertain.
The impact of the Capitanian extinction event on marine ecosystems is still heavily debated by palaeontologists. Early estimates indicated a loss of marine invertebrate genera between 35 and 47%, [15] [16] while an estimate published in 2016 suggested a loss of 33–35% of marine genera when corrected for background extinction, the Signor–Lipps effect and clustering of extinctions in certain ...
Volcanic activity, particularly that of large igneous provinces, has been speculated to have been the cause of the environmental crisis. [3] The emplacement of the Namaqualand–Garies dykes in South Africa has been dated to 485 mya, the time at which the Cambrian–Ordovician extinction event occurred, although there remains no unambiguous evidence of a causal relationship between this ...