Wed Dec 24 06:51:52 UTC 2025: Okay, here’s a summary of the text and a rewrite as a news article suitable for “The Hindu” e-Paper:
Summary:
A new study using optically stimulated luminescence (OSL) dating has determined that flood sediments buried parts of the ancient Keezhadi settlement in Tamil Nadu, India, approximately 1,155 years ago. The research, conducted by the Physical Research Laboratory and the Tamil Nadu Department of Archaeology, analyzed sediment layers from excavation pits. The findings suggest that major floods from the Vaigai River led to the abandonment or relocation of the settlement and that rivers can shift course and floods can affect settlements. The study doesn’t date the construction itself, but the sediment that covers remains; this is important for understanding the site’s history and future excavation plans, helping researchers separate the time people lived there from the time nature buried what they left behind. The research adds to our understanding of the environmental changes and their impact on ancient settlements in South India. The study was published in Current Science on October 25.
News Article:
Vaigai Floods Buried Keezhadi Settlement Over a Millennium Ago, Study Reveals
CHENNAI, December 24, 2025 – A new study has shed light on the environmental forces that may have led to the abandonment of parts of the ancient Keezhadi settlement in Tamil Nadu. Researchers have determined that flood sediments from the Vaigai River buried portions of the “urban-like” structures approximately 1,155 years ago.
The research, a collaboration between the Physical Research Laboratory in Ahmedabad and the Department of Archaeology of Tamil Nadu, employed optically stimulated luminescence (OSL) dating to analyze sediment layers from excavation sites along the Vaigai. OSL dating measures the energy accumulated in quartz grains within the sediment since their last exposure to sunlight.
The findings, published in Current Science, indicate that a high-energy flood event deposited layers of sand, silt, and clay, effectively burying the brick structures and other features of the Keezhadi settlement.
“Our analysis suggests that significant flooding from the Vaigai River played a key role in covering parts of the settlement,” explained a spokesperson for the research team. “This likely led to the abandonment or relocation of its residents.”
The team analyzed four sediment samples from two different depths in excavation pits at the site. Dating the sediment layers indicated that floods started covering parts of the Keezhadi area around 1,155 years ago. One pit at 80 cm depth, was aged to about 670 years while a deeper sample from 150 cm down was aged to about 1,170 years. The river appeared to have delivered enough sediment during major floods to cover parts of the settlement.
Archaeological finds at Keezhadi, including brick walls, drainage channels, and pottery fragments, have fueled discussions about the region’s role in the Sangam period. While previous research focused on the age of the settlement itself, this study contributes a timeline of the environment.
Archaeologists say that the study provides valuable context. The study doesn’t date the construction of the bricks themselves; instead it dates the sediment that covered the remains. Knowing when the covering happened can help separate “the time people lived there” from “the time nature buried what they left behind” and guide excavation plans.
Researchers also noted that fluctuating climate conditions in South India during the late Holocene period meant settlements were vulnerable to river shifts and floods.
“This research underscores the importance of understanding the interplay between human settlements and environmental changes,” added Dr. [Fictional Archeologist’s name], a leading archaeologist not involved in the study. “It highlights how natural events can significantly impact the course of human history.”
The findings have implications for future excavations at Keezhadi, suggesting that different areas of the site may preserve older layers better than others due to varying rates of sediment accumulation. The team plans to continue its research to further refine the timeline of the Keezhadi settlement and the environmental factors that shaped its history.
First Piper 