When most people think of the oil and gas industry, there is a common misconception that vast amounts of hydrocarbons exist below ground in a type of subterranean lake. In reality, hydrocarbons are typically contained in various levels of porous rock formations. Many times, those layers of rock are contained beneath shale or impermeable rock. There are two primary types of rock types that usually contain oil. They are limestone and sandstone. These porous rocks feature a range of different pore sizes. In some cases, the pores will be connected, making it possible for fluids to be passed through the rocks. Water is often present beneath the oil.
When a well is produced, oil and gas are not the only fluids to come to the surface. Reservoir fluids containing a mixture of oil and/or gas along with water will also come to the surface. Pressure will then be reduced, sometimes resulting in insoluble carbonate scale formation. This can be problematic as it can cause a reduced flow rate, thus resulting in a loss of revenue. It can also prove to be problematic for system integrity. It is possible to inhibit the formation of scales through the use of a chemical designed specifically for scale inhibition.