Rajmahal Hills Fossil Park, Sahibganj

About Rajmahal Hills Fossil Park, Sahibganj

The Rajmahal Hills rise above the Ganga plain at Sahibganj as a distinct basalt plateau — volcanic rocks from the Rajmahal Traps eruption that accompanied the rifting of the Indian subcontinent from the Gondwana supercontinent approximately 115 million years ago. Interbedded with these basalts are sedimentary layers rich in plant fossil impressions — the flora that grew in the swampy lowlands around the eruption centres. The fossil assemblage at Rajmahal is dominated by the Gondwana flora — Glossopteris leaves that are the classic signature of the ancient supercontinent, giant tree ferns, cycads, and ginkgos — with the remarkable addition of some of the earliest known flowering plant (angiosperm) specimens anywhere in the world. The transition from spore-bearing plants and gymnosperms to flowering plants is documented in the Rajmahal beds in a way that has made the site internationally important for plant evolution research. The geological park concept at Rajmahal is in development, with a small interpretation facility established near the main fossil outcrop areas. The fossil beds themselves are accessible on foot from the main road through the hills, and specimens of the most common fossil types — leaf impressions, stem sections — can be seen in the exposed rock faces without excavation. For visitors who have seen the general Rajmahal Hills landscape from the Ganga eco-tourism site, the fossil park adds a temporal depth — the same hills that are now scenic viewpoints were once part of the Gondwana lowland forest, and the fossils underfoot are the physical remnants of those ancient trees.