Geoprofessions
"Geoprofessions" is a term coined by the Geoprofessional Business Association to connote various technical disciplines that involve engineering, earth and environmental services applied to below-ground, ground-surface, and ground-surface-connected conditions, structures, or formations. The principal disciplines include, as major categories:
- geomatics engineering
- [|geotechnical engineering];
- [|geology and engineering geology];
- [|geological engineering];
- [|geophysics];
- geophysical engineering;
- [|environmental science and environmental engineering];
- [|construction-materials engineering and testing]; and
- [|other geoprofessional services].
Geotechnical-engineering specialties
Although geotechnical engineering is applied for a variety of purposes, it is essential to foundation design. As such, geotechnical engineering is applicable to every existing or new structure on the planet; every building and every highway, bridge, tunnel, harbor, airport, water line, reservoir, or other public work. Commonly, the geotechnical-engineering service comprises a study of subsurface conditions using various sampling, in-situ testing, and/or other site-characterization techniques. The instrument of professional service in those cases typically is a report through which geotechnical engineers relate the information they have been retained to provide, typically: their findings; their opinions about subsurface materials and conditions; their judgment about how the subsurface materials and conditions assumed to exist probably will behave when subjected to loads or used as building material; and their preliminary recommendations for materials usage or appropriate foundation systems, the latter based on their knowledge of a structure's size, shape, weight, etc., and the subsurface/structure interactions likely to occur.Civil engineers, structural engineers, and architects, feasibly among other members of the project team, apply the geotechnical findings and preliminary recommendations to take the structure's design forward. They realize these preliminary recommendations are subject to change, however, because – as a matter of practical necessity related to the observational method inherent to geotechnical engineering – geotechnical engineers base their recommendations on the composition of samples taken from a tiny portion of a site whose actual subsurface conditions are unknowable before excavation, because they are hidden by earth and/or rock and/or water. For this reason, as a key component of a complete geotechnical engineering service, geotechnical engineers employ construction-materials engineering and testing to observe subsurface materials as they are exposed through excavation.
To help achieve economies on their clients' behalf, geotechnical engineers assign their field representatives – specially educated and trained paraprofessionals – to observe the excavated materials and the excavations themselves in light of conditions the geotechnical engineers opined to exist. When differences are discovered, the geotechnical engineers evaluate the new findings and, when necessary, modify their design and construction recommendations. Because such changes could require other members of the design and construction team to modify their designs, specifications, and proposed methods, many owners have their geotechnical engineers serve as active members of the project team from project inception to conclusion, working with others to help ensure appropriate application of geotechnical information and judgments.
In other cases, geotechnical engineering goes beyond a study and construction recommendations to include design of soil and rock structures. The most common of these are the pavements that make up our streets and highways, airport runways, and bridge and tunnel decks, among other paved improvements. Geotechnical engineers design the pavements in terms of the subgrade, subbase, and base layers of materials to be used, and the thickness and composition of each. Geotechnical engineers also design the earth-retention walls associated with structures such as levees, earthen dams, reservoirs, and landfills. In other cases, the design is applied to contain earth, via structures such as excavation-support systems and retaining walls. Sometimes referred to as geostructural engineering or geostructural design, these services are also intrinsic to hydraulic engineering, hydrogeologic engineering, coastal engineering, geologic engineering and water-resources engineering. Geotechnical-engineering design is also applied for structures such as tunnels, bridges, dams, and other structures beneath, on, or connected to the surface of the earth. Geotechnical engineering, like geology, engineering geology, and geologic engineering, also involves the specialties of rock mechanics and soil mechanics, and often requires knowledge of geotextiles and geosynthetics, as well as an array of instrumentation and monitoring equipment, to help ensure specified conditions are achieved and maintained.
Earthquake engineering and landslide detection, remediation, and prevention are geoprofessional services associated with specialized types of geotechnical engineering, as is forensic geotechnical engineering, a geoprofessional service applied to determine why a certain applicable type of event – usually a failure of some sort – occurred. Railway-systems engineering is another type of specialized geotechnical engineering, as are the design of piers and bulkheads, drydocks, on-shore and off-shore wind-turbine systems, and systems that stabilize oil platforms and other marine structures to the sea floor.
Geotechnical engineers have long been involved in sustainability initiatives, including the use of excavated materials; the safe application of contaminated subsurface materials; the recycling of asphalt, concrete, and building rubble and debris; and the design of permeable pavements.
All civil-engineering specialties and projects – roads and highways, bridges, rail systems, ports and other waterfront structures, airport terminals, etc. – require the involvement of geotechnical engineers and engineering, meaning that many civil-engineering pursuits are geoprofessional pursuits to a greater or lesser degree. However, geotechnical engineering has for centuries also been associated with military engineering; sappers and miners.
Engineering geology and other geology specialties
Engineering geologist.Elements of the engineering geologist specialty.
The practice of engineering geology involves the interpretation, evaluation, analysis, and application of geological information and data to civil works. Geotechnical soil and rock units are designated, characterized, and classified, using standard engineering soil and rock classification systems. Relationships are interpreted between landform development, current and past geologic processes, ground and surface water, and the strength characteristics of soil and rock. Processes evaluated include both surficial processes, and deep-seated processes.
Geotechnical zones or domains are designated based on soil and rocked geological strength characteristics, common landforms, related geologic processes, or other pertinent factors. Proposed developmental modifications are evaluated and, where appropriate, analyzed to predict potential or likely changes in types and rates of surficial geologic processes. Proposed modifications may include such things as vegetation removal, using various types of earth materials in construction, applying loads to shallow or deep foundations, constructing cut or fill slopes and other grading, and modifying ground and surface water flow. The effects of surficial and deep-seated geologic processes are evaluated and analyzed to predict their potential effect on public health, public safety, land use, or proposed development.
Typical engineering geologic applications and types of projects. Engineering geology is applied during all project phases, from conception through planning, design, construction, maintenance, and, in some cases, reclamation and closure. Planning-level engineering geologic work is commonly conducted in response to forest practice regulations, critical areas ordinances, and the State Environmental Policy Act. Typical planning-level engineering geologic applications include timber harvest planning, proposed location of residential and commercial developments and other buildings and facilities, and alternative route selection for roads, rail lines, trails, and utilities. Site-specific engineering geologic applications include cuts, fills, and tunnels for roads, trails, railroads, and utility lines; foundations for bridges and other drainage structures, retaining walls and shoring, dams, buildings, water towers, slope, channel and shoreline stabilization facilities, fish ladders and hatcheries, ski lifts and other structures; landings for logging and other work platforms; airport landing strips; rock bolt systems; blasting; and other major earthwork projects such as for aggregate sources and landfills.
While engineering geology is applicable principally to planning, design and construction activities, other specialties of geology are applied in a variety of geoprofessional specialty fields, such as mining geology, petroleum geology, and environmental geology. Note that mining geology and mining engineering are different geoprofessional fields.