Question

What is the Meghalayan age? What is the basis on which the geological time scale of the earth is classified?

Answer 1

Approach:

1. Define the Meghalayan age with correct factual data.
2. Write about the International Commission on Stratigraphy.
3. Explain about the geological time scale classification and the details of the Holocene epoch subdivision.
4. Provide a befitting conclusion.

The Meghalayan age:
The Meghalayan age is the geological time scale classification starting from 4200 years ago till present. It represents distinct characteristics due to the occurrence of mega-droughts that crushed many civilizations of that period. The age was named after Meghalaya as the age find its traces in the stalagmite layers in Mawmluh caves in the state of Meghalaya.

International Commission on Stratigraphy:
The International Commission on Stratigraphy is the largest and oldest constituent scientific body in the International Union of Geological Sciences. Its primary objective is to precisely define global units like systems, series, and stages of the International Chronostratigraphic Chart that,in turn, are the basis for the units like periods, epochs, and age of the International Geologic Time Scale; thus setting global standards for the fundamental scale for expressing the history of the Earth.

Geological time scale classification:
Geologists divide up the 4.6-billion-year existence of Earth into slices of time. Each slice corresponds to significant happenings - such as the break-up of continents, dramatic shifts in climate, and even the emergence of particular types of animals and plant life.

Holocene Epoch subdivision:
Holocene is the present epoch in the geological time scale classification. The stratigraphy commission has subdivided Holocene into

• Meghalayan age - From 4200 years ago to the present
• North Grippian - From 8200 years ago to 4200 years ago
• Greenlandian - From 11700 years ago to 8200 years ago

Anthropocene:
The Anthropocene represents earth's most recent geologic time period as being human influenced, or anthropogenic, based on overwhelming global evidence that atmospheric, geologic, hydrologic, biospheric and other earth system processes are now altered by humans. It is distinguished as a new period either after or within the Holocene, the current epoch, which began approximately 10,000 years ago (about 8000 BC) with the end of the last glacial period.

Controversy:
The decision to discriminate ages within the Holocene has drawn fire from some scientists who believe the move is premature. They question whether some of the climate shifts used as anchors for the new ages were truly global in their impact. They are also concerned that the divisions have been approved when there is still an active debate about assigning a new geologic slice of time to reflect specifically the influence of humans on the planet.

Conclusion:
The classification gives a better understanding of the climate changes during the past and its impact on the lives on earth. In that sense, the demand of the Anthropocene also holds credibility for new geological time scale as the human activities had influenced the earth in many ways.