Tim Callahan (academic)

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Timothy J. Callahan is an associate professor of geology and environmental geosciences at the College of Charleston in South Carolina. He is director of the college's Master of Environmental Studies program and has interests in hydrogeology, wetlands and water resources. [1]

Geology The study of the composition, structure, physical properties, and history of Earths components, and the processes by which they are shaped.

Geology is an earth science concerned with the solid Earth, the rocks of which it is composed, and the processes by which they change over time. Geology can also refer to the study of the solid features of any terrestrial planet or natural satellite such as Mars or the Moon. Modern geology significantly overlaps all other earth sciences, including hydrology and the atmospheric sciences, and so is treated as one major aspect of integrated earth system science and planetary science.

College of Charleston

The College of Charleston is a public sea-grant and space-grant university in Charleston, South Carolina. Founded in 1770 and chartered in 1785, it is the oldest college in South Carolina, the 13th oldest institution of higher learning in the United States, and the oldest municipal college in the country. The founders of the college include three future signers of the Declaration of Independence and three future signers of the United States Constitution. Founded to "encourage and institute youth in the several branches of liberal education," it is one of the oldest universities in the United States.

South Carolina State of the United States of America

South Carolina is a state in the Southeastern United States and the easternmost of the Deep South. It is bordered to the north by North Carolina, to the southeast by the Atlantic Ocean, and to the southwest by Georgia across the Savannah River.



Callahan holds a Ph.D. in earth and environmental science (2001) and an M.S. in geochemistry from the New Mexico Institute of Mining and Technology (1995), [1] as well as a B.A. in geology from the University of St. Thomas, St. Paul, Minnesota (1991).

Earth science or geoscience includes all fields of natural science related to the planet Earth. This is a branch of science dealing with the physical constitution of the Earth and its atmosphere. Earth science is the study of our planet’s physical characteristics, from earthquakes to raindrops, and floods to fossils. Earth science can be considered to be a branch of planetary science, but with a much older history. Earth science encompasses four main branches of study, the lithosphere, the hydrosphere, the atmosphere, and the biosphere, each of which is further broken down into more specialized fields.

Geochemistry is the science that uses the tools and principles of chemistry to explain the mechanisms behind major geological systems such as the Earth's crust and its oceans. The realm of geochemistry extends beyond the Earth, encompassing the entire Solar System, and has made important contributions to the understanding of a number of processes including mantle convection, the formation of planets and the origins of granite and basalt.

New Mexico Institute of Mining and Technology university

The New Mexico Institute of Mining and Technology is a public university in Socorro, New Mexico.

Environmental science

Callahan is a member of the American Geophysical Union, the Carolina Geological Society, the Geological Society of America and the Society of Wetland Scientists. [2] He co-authored three papers on hydrology for the 2008 South Carolina Water Resources Conference and has co-authored several other peer-reviewed articles published in the Journal of the American Water Resource Association, the Journal of Geoscience Education, the Journal of Contaminant Hydrology and elsewhere. [2]

American Geophysical Union Nonprofit organization of geophysicists

The American Geophysical Union (AGU) is a 501(c)(3) nonprofit organization of geophysicists, consisting of over 62,000 members from 144 countries. AGU's activities are focused on the organization and dissemination of scientific information in the interdisciplinary and international field of geophysics. The geophysical sciences involve four fundamental areas: atmospheric and ocean sciences; solid-Earth sciences; hydrologic sciences; and space sciences. The organization's headquarters is located on Florida Avenue in Washington, D.C.

Geological Society of America nonprofit organization for the advancement of geoscience

The Geological Society of America (GSA) is a nonprofit organization dedicated to the advancement of the geosciences.

The Society of Wetland Scientists, Inc. (SWS) is an international, professional non-profit organization devoted to promoting understanding, conservation, protection, restoration, science-based management, and sustainability of wetlands. SWS has members in governmental agencies, non-governmental organizations, academia and private consulting. However, Society membership is open to anyone with an interest in wetlands. SWS has always been known for being a forum for scientists and managers to meet and work together. Based in Madison, Wisconsin, United States, it has 3000+ members, worldwide.

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Hydrology The science of the movement, distribution, and quality of water on Earth and other planets

Hydrology is the scientific study of the movement, distribution, and quality of water on Earth and other planets, including the water cycle, water resources and environmental watershed sustainability. A practitioner of hydrology is a hydrologist, working within the fields of earth or environmental science, physical geography, geology or civil and environmental engineering. Using various analytical methods and scientific techniques, they collect and analyze data to help solve water related problems such as environmental preservation, natural disasters, and water management.

The American Association of Petroleum Geologists (AAPG) is one of the world's largest professional geological societies with more than 35,000 members as of 2017. The AAPG works to "advance the science of geology, especially as it relates to petroleum, natural gas, other subsurface fluids, and mineral resources; to promote the technology of exploring for, finding, and producing these materials in an economically and environmentally sound manner; and to advance the professional well-being of its members." The AAPG was founded in 1917 and is headquartered in Tulsa, Oklahoma; currently almost one-third of its members live outside the United States.

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Ethnogeology is the study of how geological features were understood by ancient peoples around the globe from a "place-based" perspective, in specific reference to traditional knowledge and to the stories and ideas about the Earth that were passed down through traditions and the wisdom of elders. The focus in past research tended to be on the unique ideas and knowledge of minorities and distinct cultural groups, and how this relates to universal and cross cultural knowledge discovered by humanity as a whole. Knowledge claims that are based more on universal discoveries and natural science can be found in the subjects of philosophy, chemistry, physics, biology, mathematics, and geology. The term "ethnogeology" first enters the geological literature through the work of John Murray of the University of Manitoba in Winnipeg, Canada in the mid-1990s by virtue of his studies of the Northern Cree First Nation geological worldviews in the Province of Manitoba in Canada. At that time, a cadre of geologists and geoscience educators - particularly Dr. Steven Semken of Navajo Community College in Shiprock, New Mexico and colleagues - were examining the interesting connections among Native American traditional knowledge, geoscience concepts, and the unique vision of planet Earth's history as articulated by indigenous ethnogeological wisdom.

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  1. 1 2 "MES Faculty Members" Archived 2011-10-08 at the Wayback Machine ., College of Charleston. Retrieved 2010-01-28.
  2. 1 2 Dr. T. J. Callahan brief biography. Retrieved 2010-01-29.