Dominican amber
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Dominican amber differentiates itself from Baltic amber by being nearly always transparent, and it has the higher number of fossil inclusions, which have enabled the detailed reconstruction of the ecosystem of a long-vanished tropical forest (Poinar 1999). It is also the youngest amber found: from Oligocene to Miocene, 10 to 30 million years old.
There are three main sites in the Dominican Republic where amber is found: La Cordillera Septentrional, in the north, and Bayaguana and Sabana de la Mar, in the east. In the northern area, the amber-bearing unit is formed of clastic rocks, washed down with sandstone and other sediments that accumulated in a deltaic environment, even in water of some depth.
In the eastern area, the amber is found in a sediment formation of organic-rich laminated sand, sandy clay, intercalated lignite as well as some solvated beds of gravel and calcarenite.
Both areas seem to have been part of the same sedimentary basin but were later disrupted by movements along major faults. (Iturralde-Vincent and MacPhee, 1996).
According to Poinar, 2001, Dominican amber dates from Oligocene to Miocene, up to 30 Mya old. The oldest, and hardest of this amber comes from the mountain region north of Santiago. The La Cumbre, La Toca, Palo Quemado, La Bucara, and Los Cacaos mining sites in the Cordillera Septentrional not far from Santiago. There is also amber in the south-eastern Bayaguana/Sabana de la Mar area. It is less expensive, but softer, sometimes brittle and suffers oxidation afer being taken from the mines. There is also copal found with only an age of 15-17 million years.
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[edit] Mining
Since the amber in these mountains is tightly imbedded in a lignite layer of sandstone with a high carbon content, the digging is made between the harder strata, which in some sites has been pushed up by orogenic forces to uneven angles. The result of this is that mines are usually just angled holes, dug into the sides of cliffs. The miners accomplish their work only with the help of primitive, simple tools and risk their lives daily.
[edit] Variations
Dominican amber can be found in many colors, besides the obvious amber. Red, green, yellow, orange and even blue amber are fairly common.
The Museo del Ambar Dominicano, in Puerto Plata, has a collection of amber specimens, including many with fossils.
[edit] Movies
Dominican amber played a major part in the movie Jurassic Park, where dinosaur DNA is taken from mosquitoes embedded in Dominican amber and cloned. There are, however, several obvious mistakes with this approach.
- Mosquitoes in Dominican amber are approximately 30 million years old, from the Oligocene to Miocene period. The last dinosaur died out approximately 65 million years ago, at the end of the Cretaceous period.
- There are no major dinosaur finds in the Dominican Republic, particularly not those featured in the movie.
- Recoverable sections of DNA strands would be too fragmentary and degraded to be of use.
As a side note, the mine featured in the movie is a far cry from the actual mines in existence. Compare movie set with the image above. Also, the miners spoke a very clear Mexican accent, as opposed to the Dominican dialect known as Cibaeño.
[edit] External links
- PBS NOVA "Amber: Jewel of the Earth"
- ISEM Research: Anolis lizard in amber
- American Museum of Natural History: Amber: Window to the Past, 1998
- Life in Amber includes numerous further links
- George Poinar, Jr. and Roberta Poinar, 1999. The Amber Forest: A Reconstruction of a Vanished World, (Princeton University Press)
- Christine Lipkin, "Geological setting and age of the Domionican Republic"