Versteinertes Holz
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mit Natrolit u. Calcit gefüllte Ausgussformen von fossilen Hölzern Ästchen mit ca. 3 bis 10cm Länge Tertiär Mount Elgon, Uganda (an der Grenze zu Kenia), Afrika
hochinteressante Funde, die bisher so gut wie nie in Holz-Sammlungen auftauchten ...
Mount Elgon is an extinct shield volcano situated on the border between Kenya and Uganda. It is the oldest and largest solitary volcano in East Africa, covering an area of around 3500 km². The nepheline tuff-beds on the lower slopes of the mountain are fossil-bearing and yield distinctive fossil wood (fig. 1-4). These layers of volcanic agglomerate out-crop in caves on outliers of the mountain, such as Walasi Peak on its western side. The petrified wood is particularly interesting material as it marks the onset of renewed activity after a quiet period in the volcanic history of Mount Elgon. Natrolite, calcite and naturalist minerals (fig. 5-6) have replaced the wood tissue. The mineralized wood fragments are all that is left of the ancient forests that clothed the dormant volcano. Their age is indeterminate; but the fossils are at least pre-Pleistocene in origin. The topography and geology of Mount Elgon, and the petrography of its lavas, have been described by Odman (1930) and more background on the fossil wood from this locality can be found in a series of papers by Bancroft (1932-1935). Nowadays, the area is protected by two National Parks (one on each side of the Uganda-Kenyan border).
Zweigstück mit seitlichem Astabgang
gegabelter Ast mit Natrolit- und Calcit-Kristallen
Knäuel aus etlichen Ästchen mit wunderschönen Kristallfüllungen
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