The following are a few fields within the geology spectrum:

Environmental Geologist

Environmental geologists look for solutions to environmental issues by observing and investigating flooding, erosion, earthquakes, pollution, and natural hazards. They specifically focus on studying and understanding the earth and human interactions with the land, so as to forecast any geological issues and impacts on the environment due to the effects of urban and industrial expansion. Their research and work is vital to finding successful ways to reducing the negative effects of growth.

Duties for environmental geologists may involve: collecting soil, sediment, rock and core samples; conducting surveys; studying the effects of erosion and sedimentation; and recording information from reports, geochemical surveys, imagery, and maps.

Engineering Geologist

Engineering geologists can work as advisors to private and public companies on the environmental and geological issues for real estate development by assessing whether the ground rock is stable and safe enough to build on.

An engineering geologist investigates the physical and chemical properties of rocks and soil - this information is carried over to building bridges, dams, structures, roads, and tunnels in structurally sound areas and at minimal cost. Some knowledge of civil engineering is also recommended for the civil planning aspect.

Marine Geologist

Marine geologists are a subset of geologists that study the processes (such as plate tectonics, volcanic activity, and earthquakes) of the land form that is beneath the ocean. This includes the ocean floor, beaches, estuaries, some coastal river areas and large lakes, and the shallow slopes/shelves that surround the continents.

Marine geologists are more involved in the results of geology, rather than the causes. They focus on the interplay between geology, marine biology, and oceanography, as the bottom of the ocean is still an unexplored frontier. Studying and maintaining the health of our coastal and offshore resources is vital to our economy - there is a large amount of natural gas and oil that is beneath our oceans, and the skills and new technologies that marine geologists bring to the table are essential as we surpass peak oil.

Planetary Geologist

Planetary geology is concerned with studying the geology of the planets and their moons, asteroids, comets, and meteorites. Planetary geologists look at things like the make-up of the minor bodies of the Solar System, planetary volcanism, impact craters, what the internal structure of the moon is, or how planets like Pluto, Saturn or Jupiter were originally formed.

Planetary geology is closely linked with Earth-based geology, and applies geological science to other planetary bodies. By either working with actual specimens that were gathered from space missions, or from analyzing photos, planetary geologists can set about understanding the climate, history, and topography of other planets.

Economic Geologist

Economic geology is a subset of geology that is concerned with the formation and extraction of earth materials such as precious and base metals, petroleum minerals, nonmetallic minerals, construction-grade stone, coal, and water that can be used for economic potential and/or industrial purposes in society. Economic potential refers to materials that are currently or may potentially be valuable, typically referred to as mineral resources (they include minerals, oil, gas, and ore deposits).

Most of our modern conveniences (for example computers and plastics) rely on the Earth's natural resources and once started as raw materials. The earth's population is estimated to hit over 9 billion by 2050 - more people means more natural resources will be needed. An economic geologist's primary objective is to locate profitable deposits of oil, gas, and minerals and to figure out how to extract them. Economic geologists continue to successfully expand and define known mineral resources.

Petroleum Geologist

A petroleum geologist is involved in identifying possible oil deposits/traps, oil discovery, and production. They are called upon to study sediment deposits in oceans, rock folds, and faults. They also make the decision of where to drill by locating prospects within a sedimentary basin. This can be very labour-intensive work that involves special equipment to look at sedimentary and structural aspects in order to locate possible oil traps.

Petroleum geologists determine a prospect’s viability by looking for: a source rock that can generate hydrocarbons; porous rock reservoirs that are sealed and that collect hydrocarbons in a trap; traps that are formed in a specific geological order; a cracking of organic matter into gas and oil when under heat and pressure; and the movement of gas and oil from the source rock- to a reservoir rock- to a trap. Data may be obtained via geophysical surveys and from the mudlogger, who analyzes the drill cuttings and the rock formation thicknesses.

Geomorphologist

Geomorphologists study how the Earth’s surface is sculpted or morphed by streams, landslides, glaciers, and wind. Volcanos, earthquakes, and tsunamis also fall within the interests of geomorphologists. As rock and sediment is worn away and moved to other areas (erosion or deposition) by certain processes, landforms are produced. By studying, documenting, and mapping these landforms/landscapes and how air, water, and ice has affected them, geomorphologists can better understand how and why they form. Often particles and organic material, such as diatoms and macrofossils, that are preserved in sediments and peat can give hints on past climate changes and processes.

Geomorphologists can specialize in aeolian (desert) geomorphology, glacial and periglacial geomorphology, volcanic and tectonic geomorphology, and planetary geomorphology.

Geophysicist

A geophysicist studies the Earth by using gravity and magnetic, electrical, and seismic methods. Research geophysicists study the earth's internal structure, earthquakes, the ocean and other physical features using these methods. Some geophysicists study the earth's properties for environmental hazards and assess areas for construction sites.

Investigating the inner workings of the earth, geophysicists focus upon the physical and fluid properties of materials making up the earth, seeking a greater understanding of continental formation and processes that happen because of it (earthquakes, etc). Geophysicists also focus on finding oil, iron, copper, and many other deposits of minerals created by the earth's movement and compression of materials.

Geohydrologist

Geohydrologists study the properties and distribution of natural underground water reservoirs, their capacity to store water, and the movement of water through the reservoirs. More importantly, geohydrologists investigate the cycles of drawing out water from the reservoirs for human consumption, as well as the replenishment by precipitation.

Paleontologist

Making deductions about ancestral climates and environmental conditions through fossil records is the job of a paleontologist, a type of geologist. We can understand so much more about the past earth thanks to these researchers who analyze deposited layers of rock and soil for clues about pre-historic times. A paleontologist works with evolutionary biology, determining the factors that made species go extinct and those that brought about the origin of species as well.

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