Outline map of Northamptonshire area in Jurassic period
Middle Jurassic Northamptonshire, about 168 million years ago, was very different from today. It was a greenhouse world whose atmosphere had about 5 times the CO₂ than now, a mean global surface temperature between 5 and 10 degrees Celsius higher, and deep ocean temperatures around 8 degrees Celsius above those at present. The giant continent of Pangea was beginning to break up. At this time, this area of Britain was part of a narrow seaway between a low-lying landmass to the south-east (the London Platform) and the Wales-Pennine landmass to the north-west. This offshore setting was home to a variety of marine life including oysters, sea urchins, belemnites, bivalves, and brachiopods. Land was not too far away as evidenced by occasional pieces of fossil wood and land plant fossils.
This fossil example is the brachiopod Kallirhynchia sharpi, a filter feeder. It was found at the base of the Blisworth Limestone. It is named after Samuel Sharp (1815-83), an eminent local geologist and archaeologist who donated a portion of his geological collection to Northampton. In 1870 and 1873 his research into Northamptonshire’s geology resulted in the publication by the Geological Society of London of “The oolites of Northamptonshire".
Number 1 of the objects selected for the A History of Northamptonshire in 100 Objects Exhibition 2025
This flint dagger was found in a male burial in a barrow along with other grave goods. It had never been used so may have been an ornamental or ritual piece.
Northamptonshire’s ironstone was formed from iron-rich sediments in the Jurassic period. Quarried since Roman times, ironstone has shaped our landscape, fuelled the county's industry and built our houses.
© NMAG
© Steve Pulley
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NMAG
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NMAG
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NMAG
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NMAG