Keezhadi and Its Archaeological Importance
Floods Buried Keezhadi Settlement Around a Millennium Ago: Keezhadi is a major archaeological site located along the Vaigai River floodplain in Sivaganga district of Tamil Nadu. Excavations have revealed brick structures, drainage channels, floors, and pottery that reflect a well-planned settlement.
These findings closely resemble urban descriptions found in Sangam literature, suggesting organised habitation and social complexity. However, the structures are not visible on the surface and lie buried under thick sediment layers.
Static GK fact: Keezhadi excavations are among the most significant archaeological discoveries linked to early historic Tamil society.
Need for Dating the Burial Layers
Artefacts alone cannot explain when the settlement declined or was abandoned. The key challenge was identifying when natural forces covered the site.
The ancient habitation layers are overlain by sand, silt, and clay deposits. Dating these sediments helps distinguish human occupation from later environmental events.
This approach shifts focus from structures to the burial sediments, offering a clearer environmental timeline.
Using Light to Measure Time
Scientists from the Physical Research Laboratory and the Tamil Nadu State Department of Archaeology applied Optically Stimulated Luminescence (OSL) dating.
OSL dating estimates when mineral grains were last exposed to sunlight. Once buried, the minerals accumulate trapped energy, which can be measured in laboratories.
Four sediment samples were collected from two excavation pits at different depths. This careful sampling ensured reliable chronological sequencing.
Static GK Tip: OSL dating is commonly used in archaeology to date sediments, not organic materials or structures.
Evidence of Repeated Flooding
The OSL results span nearly 1,200 years, with deeper layers showing older dates and shallower layers showing younger ones. This clear depth-age relationship confirms repeated sediment deposition.
Fine silty clay layers were found directly above brick structures. Beneath them lay coarser sand deposits, indicating a high-energy flood event followed by calmer water conditions.
Based on sediment characteristics and dates, researchers concluded that major flooding buried parts of the Keezhadi settlement around 1,155 years ago.
Climate Context and River Dynamics
The findings align with late Holocene climate variability, a period marked by alternating wet and dry phases in South India. Rivers during this time frequently changed course and flooded surrounding plains.
Today, the Vaigai River flows several kilometres away from Keezhadi. This shift supports evidence of long-term landscape transformation.
Flooding not only buried the settlement but also altered habitation patterns, forcing communities to relocate.
Static GK fact: Floodplains are highly dynamic landscapes shaped by sediment deposition and river migration over centuries.
Archaeological Implications
The study clarifies that the flood event did not mark the beginning of Keezhadi but rather a natural episode that sealed earlier habitation layers.
This understanding helps archaeologists plan deeper and more targeted excavations. It also strengthens interpretations linking Keezhadi to early urban traditions in Tamil Nadu.
The research highlights how environmental forces play a crucial role in preserving archaeological sites.
Static Usthadian Current Affairs Table
Floods Buried Keezhadi Settlement Around a Millennium Ago:
| Topic | Detail |
| Site Location | Keezhadi, Sivaganga district, Tamil Nadu |
| River System | Vaigai River floodplain |
| Scientific Method | Optically Stimulated Luminescence dating |
| Key Finding | Settlement buried around 1,155 years ago |
| Nature of Event | High-energy river flooding |
| Climate Phase | Late Holocene variability |
| Study Focus | Dating burial sediments, not structures |
| Archaeological Value | Evidence of early organised habitation |
