Answer
The primary basis for distinguishing chemical sedimentary rocks is their mineral composition and the process of their formation, while the naming of detrital rocks is based on the size of the dominant grains and their texture. The naming conventions in both cases help geologists classify and identify different types of sedimentary rocks based on their distinct characteristics.
Work Step by Step
The primary basis for distinguishing and naming different chemical sedimentary rocks is their mineral composition and the process of their formation. Chemical sedimentary rocks are formed through the precipitation of minerals from solution, often in aqueous environments. The specific minerals present and the environmental conditions under which they precipitate determine the rock's name. Common examples of chemical sedimentary rocks include limestone (composed mainly of calcium carbonate), dolostone (composed mainly of dolomite), and evaporites (such as rock salt or gypsum), among others.
The naming of chemical sedimentary rocks focuses on the dominant mineral or mineral composition and the mode of precipitation. For example, limestone is named based on its high calcium carbonate content, which is typically derived from the remains of marine organisms or from the direct precipitation of calcium carbonate from seawater.
On the other hand, the naming of detrital sedimentary rocks, also known as clastic sedimentary rocks, is primarily based on the grain size and texture of the rock. Detrital rocks are formed from the fragments and grains of pre-existing rocks that have been weathered, transported, and deposited. The naming of detrital rocks is often based on the size of the dominant grains. For example, conglomerate consists of rounded gravel-sized grains, sandstone is composed of sand-sized grains, siltstone contains silt-sized grains, and shale consists mainly of clay-sized particles.
In summary, the primary basis for distinguishing chemical sedimentary rocks is their mineral composition and the process of their formation, while the naming of detrital rocks is based on the size of the dominant grains and their texture. The naming conventions in both cases help geologists classify and identify different types of sedimentary rocks based on their distinct characteristics.
