Types of Carbonate Cement
Beachrock is a type of carbonate beach sand that has been cemented together by a process called synsedimentary cementation. Beachrock may contain meniscus cements or pendant cements. As the water between the narrow spaces of grains drains from the beachrock, a small portion of it is held back by capillary forces, where meniscus cement will form. Pendant cements form on the bottom of grains where water droplets are held.
Hardgrounds are hard crusts of carbonate material that form on the bottom of the ocean floor, below the lowest tide level. Isopachous (which means equal thickness) cement forms in subaqueous conditions where the grains are completely surrounded by water (Boggs, 2006).
Carbonate cements can also be formed by biological organisms such as Sporosarcina pasteurii, which binds sand together given organic compounds and a calcium source.
Read more about this topic: Cementation (geology)
Famous quotes containing the words types of, types and/or cement:
“Our children evaluate themselves based on the opinions we have of them. When we use harsh words, biting comments, and a sarcastic tone of voice, we plant the seeds of self-doubt in their developing minds.... Children who receive a steady diet of these types of messages end up feeling powerless, inadequate, and unimportant. They start to believe that they are bad, and that they can never do enough.”
—Stephanie Martson (20th century)
“The wider the range of possibilities we offer children, the more intense will be their motivations and the richer their experiences. We must widen the range of topics and goals, the types of situations we offer and their degree of structure, the kinds and combinations of resources and materials, and the possible interactions with things, peers, and adults.”
—Loris Malaguzzi (1920–1994)
“Between married persons, the cement of friendship is by the laws supposed so strong as to abolish all division of possessions: and has often, in reality, the force ascribed to it.
”
—David Hume (1711–1776)