Final answer:
The three basic groups of chemical sedimentary rocks are clastic, formed from cemented particles; chemical, resulting from evaporating water leaving behind mineral precipitates; and organic, stemming from the accumulations of organic debris.
Step-by-step explanation:
The Three Basic Groups of Chemical Sedimentary Rocks
Sedimentary rocks are broadly categorized into three types based on their formation processes: clastic, chemical, and organic. Clastic sedimentary rocks form from the weathering and erosion of pre-existing rocks, which then get cemented together. The classification of clastic rocks is based on grain size, as seen in materials like sandstones, shales, and siltstones. Chemical sedimentary rocks result from the evaporation of water, leaving behind minerals as precipitates. Examples include salt from evaporite deposits and limestone from sea bottoms. Lastly, organic sedimentary rocks stem from the accumulation of organic debris, leading to the formation of coal, oil, and natural gas. There is also a subcategory called biochemical sedimentary rocks, like those formed from the shells of organisms such as foraminifera.