{"thcode":2,"term":{"code":2279,"name":"thermal maturation","parent":435,"scope":"Chemical alteration of organic material within sediments and sedimentary rocks as a result of heat. Measures of thermal maturation indicate the extent of transformation of detrital organic material into coal and petroleum."},"uf":[{"name":"thermal indices","usewith":false},{"name":"thermal maturity","usewith":false},{"name":"vitrinite reflectance","usewith":false}],"bt":[{"code":435,"name":"geochemical processes","parent":101,"scope":"Processes affecting the amount, distribution, or structure of chemical elements in air, water, soil, rocks, and minerals."},{"code":101,"name":"biological and physical processes","parent":1174,"scope":"All continuing activities, functions, and phenomena associated with organisms and non-living matter."},{"code":1174,"name":"topics","parent":1,"scope":"Themes, subjects, and concerns for which USGS information resources are relevant."},{"code":1,"name":"Categories","parent":null,"scope":"Thematic terms for categorizing information resources.  This thesaurus is intended to support finding and understanding scientific information."}],"nt":[],"rt":[{"code":955,"name":"Raman spectroscopy","parent":619,"scope":"Non-destructive chemical analysis technique in which a sample of material is irradiated with visible or near-infrared light from a laser, and the wavelength-dependent observations are used to understand chemical structure, phase and polymorphy, crystallinity and molecular interactions of the material."},{"code":172,"name":"coal resources","parent":799,"scope":"Fuel resources such as anthracite, lignite, bituminous coal, or coke, consisting largely of carbonaceous material and formed from fossilized plants."},{"code":1367,"name":"earth material properties","parent":287,"scope":"Physical characteristics of rocks and unconsolidated earth materials such as soils and sediments."},{"code":2295,"name":"hydrocarbon reservoir processes","parent":101,"scope":"Interactions among groundwater, hydrocarbons, and rock properties of subsurface geological formations, affecting the potential of those formations to form, trap, and permit the passage and extraction of hydrocarbons."},{"code":829,"name":"oil resources","parent":799,"scope":"Deposits (pools) of highly valuable liquid hydrocarbons or fossil fuels."}]}