SHILLONG: Krem Mawmluh in Sohra was the cave that was studied by the California team of geologists that finally resulted in coining the new geological time ‘Meghalayan Age’, related to a period of drought 4,200 years ago in Earth’s history.
Local caver Brian D. Kharpran Daly, who accompanied the scientists from California to Krem Mawmluh, told The Shillong Times on Thursday that the first batch of scientists and researchers led by Ashish Sinha from California studied the cave in 2003 and later researcher Sebastian Breitenbach joined the team.
The confirmation of ‘Meghalayan Age’ was after analysing stalagmites of Krem Mawmluh.
“The analysis of stalagmite in caves can pinpoint different periods and the study of stalagmite at Krem Mawmluh resulted in coining the new Meghalayan Age,” he said.
The study revealed the period of drought that began 4,200 years ago and lasted 200 years affecting many countries.
The drought resulted in the collapse of civilisations and human migrations in Egypt, Greece, Syria, Palestine, Mesopotamia, the Indus Valley and the Yangtze River Valley. Evidence of the 4,200-year climatic event has been found in all the seven continents.
Concern over damage
to caves
Daly is happy over recognition to Meghalaya through the study of the cave. However, he urged the authorities to protect the caves as limestone mining has affected the cave system, which is fragile.
Daly said Krem Mawmluh is also affected by mining of lime stones for use in Mawmluh Cherra Cements Limited.
PTI adds from London: The new phase in earth’s history defined as ‘Meghalayan Age’ which began 4,200 years ago experienced an abrupt mega-drought and cooling around the globe.
Sediments collected by an international team of researchers, including those from a stalagmite from a cave in Meghalaya helped define the smallest climatic event in Earth’s history. Agriculture-based societies, which developed in several regions after the end of the last Ice Age, were impacted severely by the 200-year climatic event.
The Late Holocene Meghalayan Age was ratified as the most recent unit of the Geologic Time Scale after many years of research.
) Two other ages – the Middle Holocene Northgrippian Age and the Early Holocene Greenlandian Age with beginnings defined at climatic events that happened about 8,300 years and 11,700 years ago, respectively, were also approved.
The three ages comprise the Holocene Epoch, which represents the time since the end of the last Ice Age.
The Meghalayan Age is unique among the many intervals of the Geologic Time Scale in that its beginning coincides with a global cultural event produced by a global climatic event, said Stanley Finney, a professor at Long Beach State University in the US and Secretary General of the International Union of Geological Sciences (IUGS) in France.
The International Commission on Stratigraphy, which is responsible for standardising the Geologic Time Scale, approved the definition of the beginning of the youngest unit of the Geologic Time Scale based on the timing of this event. The Commission then forwarded these proposals to its parent body, the IUGS, for consideration, and the executive committee of IUGS voted unanimously to ratify them.
Units of the Geologic Time Scale are based on sedimentary strata accumulated over time and contain within them sediment types, fossils and chemical isotopes that record the passage of time as well as the physical and biological events that produced them.
The three new ages of the Holocene Epoch are represented by a wealth of sediment that accumulated worldwide on the sea floor, on lake bottoms, as glacial ice, and as calcite layers in stalactites and stalagmites. Those intervals of sedimentary strata on which the ages are based are referred to as stages, and together the strata of three new stages comprise the Holocene Series.
The lower boundary of the Greenlandian and Northgripppian stages are defined at specific levels in Greenland ice cores. The lower boundary of the Meghalayan Stage is defined at a specific level in a stalagmite from a cave in northeast India. The ice cores and the stalagmite are now identified as international geostandards, and have been placed in protected archives accessible for further study.
The decision to define these new stages of the Holocene Series and thus the three new corresponding ages of the Holocene Epoch allows for an update to the International Chronostratigraphic Chart, which depicts the timeline for the Earth’s full geologic history.
