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We are all in the midst of a new geological era, experts say.
This age, nicknamed the Meghalayan, began 4,250 years ago when what was probably a global drought hit the Earth, according to the International Union of Geological Sciences. (IUGS).
The Meghalayan is just one of three newly named ages, the IUGS said in an announcement on July 13. The other two ages are Greenlanders (11,700 at 8,326) and Nordgrippians (8,326). 4,250 years ago), said the UISG. [Spectacular Geology: Amazing Photos of the American Southwest]
Geologists have systematically divided, and named, the entire Earth's history of about 4.54 billion years. From the longest to the shortest, these durations are known as eons, eras, periods, and ages. Currently, we are in the Phanerozoic, Cenozoic, Quaternary, Holocene and (as mentioned) Age Meghalayan era.
The IUGS shared an image of the newly named ages in a tweet . However, the group later released a correction on the length of the Meghalayan. (This age goes to the present, not to 1950 as the IUGS tweeted by mistake.) You can see a larger version of the newly updated chart (also called the international chronostratigraphic chart) here.
The latest version of the International Chronostratigraphic Chart / Geological Time Scale is now available! Nine # Holocene Subdivisions: #Greater (11,700 yr b2k) #Northgrippian (8326 BC) #Meghalayan (4200 BCE) ) https://t.co/IhvZHfHnWh#ChronostratigraphicChart208 pic.twitter.com/8Pf9Dnct7h
– IUGS (@theIUGS) July 13, 2018
To determine the time from the beginning of each era, scientists examined the unique chemical signatures found in the rock samples of the time; each signature relates to a major climatic event, said the UISG in a statement
The Greenlander, the earliest age of the Holocene (also known as the "lower Holocene" "), began 11,700 years ago. The Northgrippian (also known as the "Middle Holocene") began 8,300 years ago, when the Earth suddenly began to cool, probably because large amounts of fresh water from glaciers melted in the North Atlantic and disrupted the ocean. currents, the BBC reported.
Meanwhile, the Meghalayan (also called "Upper Holocene") began 4,250 years ago, when a mega-drought devastated civilizations around the world, including Egypt, Greece, Syria, Palestine, Mesopotamia and India. Yangtze River Valley, reported the BBC. This drought lasted 200 years and was probably caused by changes in ocean and atmospheric circulation.
Geologists chose the name "Meghalayan" as a sign of a rock sample that they badyzed from Meghalaya, a state in northeastern India. remains of the clouds "in Sanskrit." By badyzing a stalagmite that grows on the ground of the cave of Mawmluh, geologists have found that each layer of stalagmites has different levels of oxygen isotopes, or versions of oxygen with different numbers of neutrons.This change marks the weakening of the conditions of the monsoon from this moment, reports the BBC
"The isotopic shift reflects a 30% decrease in the monsoon, Mike Walker, professor emeritus of Quaternary science at the University of Wales in the United Kingdom, who led the naming of the ages, told the BBC. [In Photos: The U.K.’s Geologic Wonders]
Walker added that "both most significant changes occur around 4,300 and about 4,100 years before the present, so that the midpoint between the two would be 4,200 years ago. "
Controversial Age
is satisfied with the new naming scheme for ages. Meghalayan was introduced just six years ago, in a 2012 study in the Journal of Quaternary Science.
Some geologists say that it is too early to name the Holocene ages because it is unclear whether climate change is truly global. BBC reported. Meanwhile, the name "Anthropocene epoch" has been floated as a geological period marked by the dramatic impact that humans have had on Earth, but this name has not yet been formally submitted to the United States. IUGS, the organization said on Twitter
Original article on Live Science
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