Posted by Mockrowten on Jun 15, 2003 at 12:32
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CHRONOLOGY OF STONEHENGE CONSTRUCTION MATERIALS
The outcrop sedimentary rocks at Stonehenge are the Late Cretaceous, Santonian Age, calcium carbonates. The outcrop sedimentary rocks comprise the first construction material used by the Stonehenge builders. This material is approximately 85 million years old. These rocks are locally called the Seaford Chalk Formation (Stonehenge White Chalk).
The oldest limestone sedimentary rocks at Stonehenge are the Mississippian Period (Early Carboniferous), Arundian Age, calcium carbonates. The Mississippian Period limestone sedimentary rocks comprise the first (1st) foreign construction material used by the Stonehenge builders. This material is approximately 340 million years old. These rocks are locally called the Birnbeck Limestone Formation (Stonehenge Whitestones).
The volcanic rocks (oldest geologically) at Stonehenge are the Ordovician Period intrusive igneous diabases (dolerites), and extrusive igneous felsites (rhyolites) and tuffs (basic). The Ordovician Period igneous rocks comprise the second (2nd) foreign construction material used by the Stonehenge builders. This material is approximately 470 million years old. These rocks are locally called the Ordovician Volcanics (Stonehenge Bluestones).
The oldest sandstone sedimentary rocks at Stonehenge are the Silurian and Devonian Period micaceous sandstones. The Silurian and Devonian Period sedimentary sandstone rocks comprise the third (3rd) foreign construction material used by the Stonehenge builders. This material is approximately 417 million years old. These rocks are locally called the Old Red Sandstone Formation (Stonehenge Coshestons).
The youngest sandstone sedimentary rocks at Stonehenge are the Oligocene and Miocene Period silicates. The Oligocene and Miocene Period sandstone sedimentary rocks comprise the fourth (4th) foreign construction material used by the Stonehenge builders. This material is approximately 24 million years old. These rocks are locally called the Reading Formation (Stonehenge Sarsens).
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Re: Chronology of Stonehenge Construction Materials Mike Kremer 15/6 18:32
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