Kerogeenityypin

Kerogeenityypin refers to the classification of kerogen, which is the insoluble organic matter found in sedimentary rocks. Kerogen is a complex mixture of organic compounds that has been transformed from original biological materials by heat and pressure over geological time. Its composition and origin significantly influence the type and amount of hydrocarbons that can be generated from the rock.

There are three main types of kerogen: Type I, Type II, and Type III. Type I kerogen is typically derived from algal or lacustrine (lake) organic matter. It is characterized by a high hydrogen-to-carbon ratio and is hydrogen-rich, making it very oil-prone. Rocks containing Type I kerogen are considered excellent source rocks for generating liquid petroleum.

Type II kerogen originates from marine plankton and other marine organisms. It has a moderate hydrogen-to-carbon ratio and is considered gas- and oil-prone. While it can generate both oil and gas, it is generally considered more oil-prone than Type III. Marine shales are common examples of rocks containing Type II kerogen.

Type III kerogen is derived from terrestrial plant material, such as woody debris and humic matter. It has a low hydrogen-to-carbon ratio and is carbon-rich, making it gas-prone. Rocks rich in Type III kerogen are primarily sources for natural gas. The classification helps geologists predict the type of hydrocarbon potential within a sedimentary basin.