coal ball उदाहरण वाक्य
उदाहरण वाक्य
- Some coal balls from the US vary in age from the later end of the Stephanian ( roughly 304 to 299 mya ).
- For instance, the very first sentence in the very first book in this search says that coal balls are found in the Permian.
- Their unique preservation of Carboniferous plants makes them valuable to scientists, who cut and peel the coal balls to research the geological past.
- "' Coal balls "', despite their name, are calcium-rich masses of geological past of the Earth.
- During Stopes's time at Manchester, she studied coal and coal balls and researched the collection of Glossopteris ( Permian seed ferns ).
- Mixed coal balls are further divided into heterogeneous, where the plant and animal material was distinctly separated; and homogeneous, lacking that separation.
- Since then, coal balls have been discovered in other countries and they have led to the discovery of over 300 species and 130 genera.
- His scientific research, besides his early original work on fossil plants and coal balls, was chiefly concerned with vertebrate palaeontology, especially fossil reptiles.
- Coal balls often preserve a remarkable record of the microscopic tissue structure of Carboniferous swamp and mire plants, which would otherwise have been completely destroyed.
- The oldest known coal balls date from the Namurian stage of the Carboniferous; they were found in Germany and on the territory of former Czechoslovakia.