Anthropic rock

Anthropic rock is rock that is made, modified and moved by humans. Concrete is the most widely-known example of this [A. Bentur, "Cementitious Materials--Nine Millennia and a New Century: Past, Present, and Future", ASCE Journal of Materials in Civil Engineering 14: 2-22 (February 2002).] . 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 [E.C. Stone, "From shifting silt to solid stone: the manufacture of synthetic basalt in ancient Mesopotamia", Science 280: 2091-2093 (26 June 1998).] . British Victorians were very familiar with the durable mock-rock surface formations used in public parks, constructed of Pulhamite and Coade stone [I. Freestone, "Forgotten but not lost: the secret of Coade Stone", Proceedings of the Geologist's Association 105: 141-143 (1994).] . 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 gas stock and, thereby affects Earth's Greenhouse Effect. In 2007, about 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's long-identified igneous, sedimentary and metamorphic groups. His practical proposal for an "Anthropic Rocks" category [James R. Underwood, Jr., "Anthropic Rocks as a Fourth Basic Class", Environmental & Engineering Geoscience VII: 104-110 (February 2001).] 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.

Future

Future macro-engineering of the Earth may involve the total envelopment of the planet with, among other materials, concrete [Viorel Badescu and R.B. Cathcart, "Environmental thermodynamic limitations on global human population", International Journal of Global Energy Issues 25: 129-140 (2006).] .NASA and others have offered many settlement proposals that entail the use of in-situ resources of the Moon and Mars, such as brick, by astronauts.The relatively inert nature of rocks has been exploited in many methods to immobilize chemical and/or radioactive wastes; the Australian researcher, A.E. Ringwood, developed a titanate ceramic called Synroc, his acronym for "synthetic rock" [A.E. Ringwood, Safe Disposal of High-Level Nuclear Reactor Waste: A New Strategy (1978).] . D.J. Sheppard proposed Sun-orbiting space colonies, interplanetary and interstellar spaceships ought to be manufactured of concrete [D.J. Sheppard, "Concrete space colonies", Spaceflight 21: 3-8 (January 1979).] . There have also been proposals for deep-diving submarines constructed of concrete [David Cohen, "Fantastic Voyager", New Scientist 173: 36-39 (9 March 2002).] .

Alan Weisman's THE WORLD WITHOUT US (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"!

References