Logging while drillingLogging while drilling (LWD) is a technique that allows log data to be acquired during drilling operations through tools placed in the bottom hole assembly (BHA). LWD technology was developed originally as an enhancement to the earlier measurement while drilling (MWD) technology to completely or partially replace wireline logging operation.
Spontaneous potentialSpontaneous potentials are often measured down boreholes for formation evaluation in the oil and gas industry, and they can also be measured along the Earth's surface for mineral exploration or groundwater investigation. The phenomenon and its application to geology was first recognized by Conrad Schlumberger, Marcel Schlumberger, and E.G. Leonardon in 1931, and the first published examples were from Romanian oil fields.
Nuclear magnetic resonanceSpectroscopic technique based on change of nuclear spin stateBruker 700 MHz nuclear magnetic resonance (NMR) spectrometer.Nuclear Magnetic Resonance (NMR) basic principlesNuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong constant magnetic field are disturbed by a weak oscillating magnetic field (in the near field) and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic field at the nucleus.
Gamma rayA gamma ray, also known as gamma radiation (symbol γ), is a penetrating form of electromagnetic radiation arising from high-energy interactions like the radioactive decay of atomic nuclei or astronomical events like solar flares. Lower energy gamma radiation overlaps the upper end of X-ray radiation; they are distinguished by their different origins.
Oil wellAn oil well is a drillhole boring in the Earth that is designed to bring petroleum oil hydrocarbons to the surface. Usually some natural gas is released as associated petroleum gas along with the oil. A well that is designed to produce only gas may be termed a gas well. Wells are created by drilling down into an oil or gas reserve and if necessary equipped with extraction devices such as pumpjacks.
BoreholeA borehole is a narrow shaft drilled into the ground, either vertically or horizontally. Boreholes range from shallow holes just a few feet deep to engineered shafts extending hundreds or even thousands of feet underground. A borehole may be constructed for many different purposes, including the extraction of water ( through drilled wells and tube wells), other liquids (such as petroleum), or gases (such as natural gas).
Geothermal explorationGeothermal exploration is the exploration of the subsurface in search of viable active geothermal regions with the goal of building a geothermal power plant, where hot fluids drive turbines to create electricity. Exploration methods include a broad range of disciplines including geology, geophysics, geochemistry and engineering. Geothermal regions with adequate heat flow to fuel power plants are found in rift zones, subduction zones and mantle plumes.
GroundwaterGroundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available fresh water in the world is groundwater. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock become completely saturated with water is called the water table.
Hydrocarbon explorationHydrocarbon exploration (or oil and gas exploration) is the search by petroleum geologists and geophysicists for hydrocarbon deposits, particularly petroleum and natural gas, in the Earth's crust using petroleum geology. Exploration methodsVisible surface features such as oil seeps, , pockmarks (underwater craters caused by escaping gas) provide basic evidence of hydrocarbon generation (be it shallow or deep in the Earth).
Geological formationA geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers.
Mining engineeringMining engineering is the extraction of minerals from the ground. It is associated with many other disciplines, such as mineral processing, exploration, excavation, geology, metallurgy, geotechnical engineering and surveying. A mining engineer may manage any phase of mining operations, from exploration and discovery of the mineral resources, through feasibility study, mine design, development of plans, production and operations to mine closure.
Permeability (porous media)Measure of the ability of a porous material to allow fluids to pass through it Symbol used to represent in situ permeability tests in geotechnical drawings In fluid mechanics, materials science and Earth sciences, the permeability of porous media (often, a rock or soil) is a measure of the ability for fluids (gas or liquid) to flow through the media; it is commonly symbolized as k. Fluids can more easily flow through a material with high permeability than one with low permeability.*As an Amazon Associate I earn from qualifying purchases.