Minerals Report - International Seabed Authority
Minerals Report - International Seabed Authority Minerals Report - International Seabed Authority
with the German firm Preussag. As part of this study, a mining test using an adapted offshore oil-drilling vessel was conducted. The test showed that it while it was feasible to mine these deposits; mining would not yield the required returns. The discovery of these deposits did not however, trigger an interest in marine mineral resources because it was thought to be an exceptional case related to an early stage of rifting with the special layers of salt, which were very efficient at transporting metals. In 1978, a French/Mexican/American expedition made a transit across a portion of the submerged volcanic mountain range called the East Pacific Rise, off Mexico just south of the Gulf of California. A standard geological transit was planned. The water depth is about 2,000 metres and the transit was across the submerged volcanic mountain range. In the course of the transit, mounds up to about 10 metres high and very different from the normal volcanic rocks of the deep sea floor were encountered. Scientists at IFREMER in France found the samples to be sulphide rocks, and thus the first discovery of massive sulphides in the deep ocean basin was made. Many scientific discoveries were made this way by chance, serendipity, he said. The following year (1979), the American submersible "Alvin", made a dive at the same location. The implication of seafloor polymetallic massive sulphides deposits was that they are deposited from very hot, hot springs but nothing was identified during the dives in 1978 to support this supposition. During the Alvin survey, a chimney that was several metres high, billowing clouds of black smoke was discovered. The name "Black Smoker" has since been used to describe this phenomenon. The smoke was made up of mineral particles. While it was not possible to take temperature measurements or samples on this cruise due to the heat that melted the plastic windows on the submersible, newer heat tolerant instruments were used later. Temperatures were found to be nearly 400 degrees Celsius, and while temperature measurements were being taken, it was found that these structures were mineralised chimneys deposited from the hot springs that flowed up through them. The cavities inside the chimneys were lined with bright crystals of sulphides of iron and copper. The chimneys grew up to tens of metres high, and then simply collapsed and toppled over, accumulating these massive sulphides deposits around their base. INTERNATIONAL SEABED AUTHORITY 18
Another unexpected surprise was the discovery of a dense and spectacular biological community at 2000 metres depth, under pitch darkness. An oasis of life was found with new forms of life such as the giant tubeworms, which grow about as high as a person and grew in a shell-like casing made of the same material as our fingernails. Many new features to this body were found in the cracks between the lava flows. There were clams growing to exceptionally large sizes in an environment where the hot spring discharges were enriched in hydrogen sulphide. As a result of a high level of haemoglobin in their blood to extract oxygen from this toxic environment these clams have become adapted to the environment. Research on these animals will help in the studies of survival in toxic environments, he said. With regard to support for this ecosystem, Professor Rona explained that bacterial material was blowing out and accumulating like a snowfall over the sea floor in these hot spring areas. It has now been found out that these bacteria are using chemicals, particularly the hydrogen sulphide that is dissolved in the hot springs from the underlying rocks, as an energy source to grab carbon, hydrogen and oxygen from the surrounding water and combine them into carbohydrate, sugar and starches to sustain themselves and the higher forms that live on the bacteria such as the tube worms. Thus it was not only just an oasis of life on the deep sea floor, but also an oasis of life that is distinct from the life on the surface of land, which is dependent on the energy from the sun with green plants using that energy to manufacture their food at the base of the food chain. Professor Rona also explained through slides that some white spots growing like flowers on the sea floor in these hot spring areas are nourished by bacteria growing in warm water coming up through cracks. During the dive, dome shaped chimneys several metres high were encountered, discharging blue-white smoke. These were named “ white smokers”. The area in which they were found was dubbed as the 'Kremlin Area' because they reminded the scientists of the domes on the Old Russian churches. Higher temperature discharges were also encountered and at the very edge of a cluster of black smokers at the very top of a particular mound, a mass of white material could be seen. Professor Rona further went on to explain that black smokers discharge very turbulently, engulf surrounding cold water which is near freezing, with the result that temperature drops very rapidly. Within a INTERNATIONAL SEABED AUTHORITY 19
- Page 2 and 3: Workshop on Minerals Other than Pol
- Page 4 and 5: Published in Jamaica 2004 by the In
- Page 6 and 7: Chapter 6* Impact of the Developmen
- Page 8 and 9: PART 4 REGULATORY AND PROMOTIONAL F
- Page 10 and 11: The Authority designates one of two
- Page 12 and 13: deposits and gas hydrates of the co
- Page 14 and 15: Prof. Chris German, Challenger Divi
- Page 16 and 17: Mr. Sven Petersen, Research Associa
- Page 18 and 19: SECRETARIAT Ambassador Satya N. Nan
- Page 20 and 21: is to submit “an application that
- Page 22 and 23: that was established to help protec
- Page 24 and 25: on the continental margin. He state
- Page 28 and 29: metre or metres of these black smok
- Page 30 and 31: nodules in terms of these metals -
- Page 32 and 33: Professor Herzig stressed however t
- Page 34 and 35: While noting that the continuity of
- Page 36 and 37: asal diameter at 1,600 m water dept
- Page 38 and 39: discovery of the new hydrothermal s
- Page 40 and 41: esearch cruises dedicated to ferrom
- Page 42 and 43: global mid-ocean ridge system. He p
- Page 44 and 45: athymetric map of the seafloor. A s
- Page 46 and 47: were encouraging. In the course of
- Page 48 and 49: that this matter was sensitive, he
- Page 50 and 51: complete a preliminary evaluation o
- Page 52 and 53: metals - nickel, cobalt, manganese,
- Page 54 and 55: 12. Issues to be taken into account
- Page 56 and 57: entities. Many of them included min
- Page 58 and 59: In this regard, the Secretary-Gener
- Page 60 and 61: According to Dr. Vysotsky, as estim
- Page 62 and 63: With regard to current knowledge ab
- Page 64 and 65: Dr. Corbett gave a brief account of
- Page 66 and 67: River resulting in the introduction
- Page 68 and 69: Ms. Zaamwani pointed out that as th
- Page 70 and 71: geochemical and geotechnical survey
- Page 72 and 73: of its continental shelf through bi
- Page 74 and 75: also stated, is similar to that of
with the German firm Preussag. As part of this study, a mining test using an<br />
adapted offshore oil-drilling vessel was conducted. The test showed that it<br />
while it was feasible to mine these deposits; mining would not yield the<br />
required returns. The discovery of these deposits did not however, trigger an<br />
interest in marine mineral resources because it was thought to be an<br />
exceptional case related to an early stage of rifting with the special layers of<br />
salt, which were very efficient at transporting metals.<br />
In 1978, a French/Mexican/American expedition made a transit across<br />
a portion of the submerged volcanic mountain range called the East Pacific<br />
Rise, off Mexico just south of the Gulf of California. A standard geological<br />
transit was planned. The water depth is about 2,000 metres and the transit<br />
was across the submerged volcanic mountain range. In the course of the<br />
transit, mounds up to about 10 metres high and very different from the<br />
normal volcanic rocks of the deep sea floor were encountered. Scientists at<br />
IFREMER in France found the samples to be sulphide rocks, and thus the first<br />
discovery of massive sulphides in the deep ocean basin was made. Many<br />
scientific discoveries were made this way by chance, serendipity, he said.<br />
The following year (1979), the American submersible "Alvin", made a<br />
dive at the same location. The implication of seafloor polymetallic massive<br />
sulphides deposits was that they are deposited from very hot, hot springs but<br />
nothing was identified during the dives in 1978 to support this supposition.<br />
During the Alvin survey, a chimney that was several metres high, billowing<br />
clouds of black smoke was discovered. The name "Black Smoker" has since<br />
been used to describe this phenomenon. The smoke was made up of mineral<br />
particles. While it was not possible to take temperature measurements or<br />
samples on this cruise due to the heat that melted the plastic windows on the<br />
submersible, newer heat tolerant instruments were used later. Temperatures<br />
were found to be nearly 400 degrees Celsius, and while temperature<br />
measurements were being taken, it was found that these structures were<br />
mineralised chimneys deposited from the hot springs that flowed up through<br />
them. The cavities inside the chimneys were lined with bright crystals of<br />
sulphides of iron and copper. The chimneys grew up to tens of metres high,<br />
and then simply collapsed and toppled over, accumulating these massive<br />
sulphides deposits around their base.<br />
INTERNATIONAL SEABED AUTHORITY 18
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