zpravodajství životního prostředí již od roku 1999

Geologie Panamy (Panama geology)

Geologie Panamy (Panama geology)

Panamá is an igneous or magmatic arc located in a complex conjunction of four tectonic plates, known as Cocos-Nazca-Caribbean and South American plates. The cortical evolution of this area has been extremely complex. The rocks are volcanic sequences to Vulcan-sedimentary instructed by granitoid calc-alkaline bodies.

The rocks show an age ranging from 140 million to a million years old. Some of the older rocks, the so called "Proto-arc" are of basaltic composition and are located in the Azuero Peninsula, while some of the younger ones are pyroclastic flows of dactylic composition, located in "El Valle" in central Panama at around 200,000 years of age.

Panamá is located over the famous "Pacific Ring of Fire" which runs from New Zealand in the Pacific southwest, passing through New Guinea, Indonesia, Japan trough the Aleutian Islands Arc, North and South America west coast. This area is characterized by seismic activity and for its numerous volcanoes, where the convergent limit of the Pacific plate collides or sub-ducts beneath the adjacent plates. It is in these areas that you can find many of the world´s largest gold and copper deposits. High temperature fluctuations combined with the favorable chemical composition of the molten rock, allowing ore-forming hydrothermal fluids to be trapped and concentrated in fractures and fissures.

During 1519 the Spanish extracted both alluvial and disseminated gold. Christopher Columbus visited the Cocuyo mine on the Atlantic Coast on his fourth voyage. The Espiritu Santo de Cana mine on the Colombian border was operated until 1727. Estimates made showed that approximately 60 tons of gold were extracted from the "breccia pipe" that makes this mine. The first type of mining in the 20th century was conducted between 1927 to 1932 in Reman-ce and Los Hatillos.

In the 1960´s, geological mapping and prospecting program, sponsored by the UN, took place in the Central Cordillera of Panama.It resulted in the discovery of significant concentrations of Copper such as Cerro Colorado, Cerro Petaquilla and Cerro Chorcha.

More modern gold mining activities began in the 1980´s and were later resumed in the early 1990´s after the United States´ invasion. Active gold mining resumed in the early 90´s in the Remance and Santa Rosa mines.

Mineral deposits in Panama are those typically found in the Circum-Pacific belt.

Cu-Au Deposits: Cerro Colorado, Cerro Petaquilla and Cerro Chorcha.

Epithermal low sulfuration quartz adularia deposits: Remance and Santa Rosa mines. Epithermal high sulfuration deposits: Cerro Quema, Carbonate deposits of basic metals and gold: Espíritu Santo de Cana; alluvial and disseminated deposits: Cocuyo, Malgaja and La Guinea.


Komentáře k článku. Co si myslí ostatní?

Další články
Podněty ZmapujTo
Mohlo by vás také zajímat
Naši partneři
Složky životního prostředí