Search results
Results from the WOW.Com Content Network
Bentonite layers from an ancient deposit of weathered volcanic ash tuff in Wyoming Gray shale and bentonites (Benton Shale; Colorado Springs, Colorado). Bentonite (/ ˈ b ɛ n t ə n aɪ t / BEN-tə-nyte) [1] [2] is an absorbent swelling clay consisting mostly of montmorillonite (a type of smectite) which can either be Na-montmorillonite or Ca-montmorillonite.
Several different types of bentonite can be found; however, potassium bentonite is the main one associated with the Deicke and Millbrig eruptions. The Deicke and Millbrig K-bentonite layers can be found from Alabama to New York to Minnesota. These K-bentonite layers are up to a meter thick in some locations. [8] Such thickness is unique.
Bentonite usually forms from weathering of volcanic ash, most often in the presence of water. However, the term bentonite, as well as a similar clay called tonstein, have been used for clay beds of uncertain origin. For industrial purposes, two main classes of bentonite exist: sodium bentonite and calcium bentonite.
Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. [1] [2] Rock that contains greater than 75% ash is considered tuff, while rock containing 25% to 75% ash is described as tuffaceous (for example, tuffaceous sandstone). [3]
Some have vertical walls, others look like saucers or shallow basins, and some generate ponds by retaining water, according to the U.S. Geological Survey. The depressions are common in Florida ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
“The study clearly shows that antibiotic use does not increase the risk of cognitive impairment or dementia for healthy older adults. The results are encouraging, particularly given the prior ...
Formation damage is reduced by a conservative hydraulics system. A good quality filter cake containing bentonite is known to limit bore hole enlargement. In shales when using water-based mud, chemical differences can cause interactions between mud & shale that lead to weakening of the native rock. Highly fractured, dry, brittle shales can be ...