What's an account? When a computer is used by many people it is usually necessary to differentiate between the users, for example, so that their private files can be kept private. This is important even if the computer can only be used by a single person at a time, as with most microcomputers. Thus, each user is given a unique username, and that name is used to log in. There's more to a user than just a name, however. An account is all the files, resources, and information belonging to one user.
They include biochemical, clastic and evaporative sedimentary rocks. Biochemical sedimentary rocks are formed from organic processes that involve living organisms producing the sediments. These living organisms can be snails and clams whose discarded calcium carbonate shells can form limestone.
Bioclastic rocks are composed of organic debris such as plants (lignite, coal) or shells (coquina, fossiliferous limestone). Chemical Rocks. Chemical rocks precipitate from water. These include carbonates (limestone and dolomite), evaportites (halite, gypsum, anhydrite), and chert (SiO 2).Most sedimentary rocks are derived by processes of weathering, transportation, deposition, and diagenesis.The final texture (grain size, shape, sorting, mineralolgy, etc.) in a sediment or sedimentary rocks is dependent on process that occur during each stage.) Layering (bedding). One of the most obvious features of sedimentary rocks and sediment is the layered structure which they exhibit. The layers are evident because of differences in mineralogy, clast size, degree of sorting, or color of the different layers.