Anthropic rock
Encyclopedia
Anthropic rock is rock that is made, modified and moved by humans. Concrete
Concrete
Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

 is the most widely-known example of this. The new category has been proposed to recognise that man-made rocks are likely to last for long periods of Earth's future geological time, and will be important in humanity's long-term future.

History

Anthropogenic lithogenesis is a historically new event-process within the Earth. For millennia humans dug and piled only natural rocks. Archaeologists, during 1998, reported that artificial rock was made in ancient Mesopotamia
Mesopotamia
Mesopotamia is a toponym for the area of the Tigris–Euphrates river system, largely corresponding to modern-day Iraq, northeastern Syria, southeastern Turkey and southwestern Iran.Widely considered to be the cradle of civilization, Bronze Age Mesopotamia included Sumer and the...

. British
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

 Victorians
Victorian era
The Victorian era of British history was the period of Queen Victoria's reign from 20 June 1837 until her death on 22 January 1901. It was a long period of peace, prosperity, refined sensibilities and national self-confidence...

 were very familiar with the durable mock-rock surface formations used in public parks, constructed of Pulhamite
Pulhamite
Pulhamite was a patented anthropic rock 'material' invented by James Pulham of the firm James Pulham and Son of Broxbourne.Pulhamite, which usually looked like gritty sandstone, was used to join natural rocks together or crafted to simulate natural stone features. The recipe went to the grave...

 and Coade stone
Coade stone
Lithodipyra , or Coade stone, was ceramic stoneware that was often described as an artificial stone in the late 18th and early 19th centuries. It was used for moulding Neoclassical statues, architectural decorations and garden ornaments that were both of the highest quality and remain virtually...

. Concrete, as we know it today, dates from 1756. Worldwide, concrete's preparation adds at least 0.2 gigatonnes yearly to the atmosphere's CO2
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...

 gas stock and, thereby affects Earth's Greenhouse Effect
Greenhouse effect
The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions. Since part of this re-radiation is back towards the surface, energy is transferred to the surface and the lower atmosphere...

. In 2007, 7.5–8 cubic kilometers of concrete are created annually by humans.

Classification and theory

The USA geologist Dr. James Ross Underwood, Jr., born 1927, has foreseen humanity's need for a Fourth Class of rocks to be added to Earth and planetary materials studies which would supplement geology
Geology
Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...

's long-identified igneous, sedimentary and metamorphic groups. His practical proposal for an "Anthropic Rocks" category recognizes the pervading spread of humankind and its industrial products.

Dr. Underwood's theoretical innovation is a logical extension of the near-constant redefinition event-process that terms such as igneous, metamorphic and sedimentary have already undergone because of scientific progress. A survey report, including Underwood's Anthropic Rock Cycle diagram, is including in Cathcart (2011). [Cathcart, R.B.,"Anthropic Rock: a brief history", History of Geo- and Space Sciences, 2: 57-74 (2011).]

Future

Future macro-engineering
Macro-engineering
In engineering, macro-engineering is the implementation of extremely large-scale design projects...

 of the Earth may involve the total envelopment of the planet with, among other materials, concrete.
NASA and others have offered many settlement proposals that entail the use of in-situ resources of the Moon and Mars, such as brick
Brick
A brick is a block of ceramic material used in masonry construction, usually laid using various kinds of mortar. It has been regarded as one of the longest lasting and strongest building materials used throughout history.-History:...

, by astronaut
Astronaut
An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft....

s.

The relatively inert nature of rocks has been exploited in many methods to immobilize chemical
Chemical waste
Chemical waste is a waste that is made from harmful chemicals . Chemical waste may fall under regulations such as COSHH in the United Kingdom, or the Clean Water Act and Resource Conservation and Recovery Act in the United States...

 and/or radioactive waste
Radioactive waste
Radioactive wastes are wastes that contain radioactive material. Radioactive wastes are usually by-products of nuclear power generation and other applications of nuclear fission or nuclear technology, such as research and medicine...

s; the Australian researcher, A.E. Ringwood, developed a titanate ceramic
Ceramic
A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous...

 called Synroc
Synroc
Synroc, a portmanteau of "synthetic rock", is a means of safely storing radioactive waste. It was pioneered in 1978 by a team led by Dr Ted Ringwood at the Australian National University, with further research undertaken in collaboration with ANSTO at research laboratories in Lucas...

, his acronym for "synthetic rock". D.J. Sheppard proposed Sun-orbiting space colonies, interplanetary and interstellar spaceships ought to be manufactured of concrete. There have also been proposals for deep-diving submarine
Submarine
A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...

s constructed of concrete.

Alan Weisman in The World Without Us
The World Without Us
The World Without Us is a non-fiction book about what would happen to the natural and built environment if humans suddenly disappeared, written by American journalist Alan Weisman and published by St. Martin's Thomas Dunne Books. It is a book-length expansion of Weisman's own February 2005 Discover...

(2007) noted that anthropic rocks of all kinds, among other artifacts, will exist far into our planet's future even should our species disappear "tomorrow".
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK