Exploration and Mapping Techniques
In order for a company like Weatherby Energy to begin drilling, there is a need to develop and utilize exploration and mapping techniques. This helps to ensure, along with a geological analysis that the land is prime for oil production. Because there is no way of knowing for sure where the oil will be, the exploration and mapping techniques have become known as a form of art as well as a form of science. Weatherby Energy uses a variety of methods when trying to pinpoint where to drill for oil.
Subsurface mapping involves a map of the underground land where an oil company is looking to drill. Subsurface mapping is a good way that allows oil companies like Weatherby Energy to determine if there is underlying geographical features that will allow for petroleum traps to develop. Petroleum traps are known to house reservoirs, where the hydrocarbons accumulate. These hydrocarbons will later be refined into oil or natural gas depending on the type of hydrocarbon that is present. A geologist will create the subsurface map as well as provide enough evidence to the oil company – Weatherby Energy – that there is a good probability that a reservoir is located beneath the surface of a potential drilling site.
Various types of subsurface maps include:
• Geophysical surveys
• Isopach maps
• Lithofacies maps
• Structural maps and sections
Geophysical surveys provide a means of mapping out the subsurface area of a proposed drilling site. These surveys are able to map out the physical properties of underlying rock formations to detect the presence of a petroleum trap that may in turn offer a reservoir. There are several types of geophysical surveys that a geologist may use in detecting below rock formations for companies such as Couch Oil and Gas. Some of these are explained below
• Seismic Surveys – Seismic surveys send waves down into the rock formations below the surface of an area. These waves continue down into the surface of the Earth until they reach any interruption in the sedimentary rock below. These waves are then reflected back up to the Earth’s surface where they are recorded with devices and analyzed.
• Magnetic Surveys – Magnetic surveys are considered the cheaper and quickest way to measure the geology of the subsurface area. Using a magnetometer, the strengths of the earth’s magnetic fields are measured as well as the thickness of the layers of sedimentary rock where possible oil might be found.
• Gravity Surveys – Gravity surveys use gravimeters to determine if any gravity anomalies exist. From this information, contour maps can be developed for oil companies like Weatherby Energy to show large scale structures.
These are three of the major types of surveys that are done for oil companies on possible drilling sites. Other methods may include but are not limited to structural contour maps, cross-sections, isopach maps and lithofacies maps. Each of these tools is able to map the surface and subsurface of an area where oil may possibly be discovered.