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Framestone
A framestone is a special type of carbonate rock in the Dunham classification. Description The term "framestone" was not used in the original Dunham classification by Dunham (1962). It first appeared in the modified Dunham classification by Embry and Klovan (1971) where it is described as an autochthonous limestone having "in situ massive fossils which constructed a rigid three-dimensional framework during deposition. The in situ fossils therefore form the supporting framework of the rock, with matrix material occurring in the interstices between the fossils." Lokier and Al Junaibi(2016) define a framestone as "an autochthonous carbonate-dominated rock supported by a rigid organic framework developed at the time of deposition." Interpretive problems One possible problem in the interpretation of framestones is that the framework can be of different sizes from millimeters to meters, so they might not be present on the thin section. Some organisms can also be binding and build ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dunham Classification
The Dunham classification system for carbonate sedimentary rocks was originally devised by Robert J. Dunham in 1962, and subsequently modified by Embry and Klovan in 1971 to include coarse-grained limestones and sediments that had been organically bound at the time of deposition. The ''modified Dunham Classification'' has subsequently become the most widely employed system for the classification of carbonate sedimentary rocks with 89% of workers currently adopting this system over the alternative Folk classification scheme History Original classification Robert J. Dunham published his classification system for limestone in 1962. The original Dunham classification system was developed in order to provide convenient depositional-texture based class names that focus attention on the textural properties that are most significant for interpreting the depositional environment of the rocks. The three criteria used to define the original Dunham classes were: * the supporting fabric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boundstone (rock)
A boundstone is a special type of carbonate rock in the Dunham classification Description In the original classification by Dunham(1962), boundstones are defined as "carbonate rocks showing signs of being bound during deposition [...]. The signs of binding are specific and occur within the sample being classified" In the modified Dunham classification by Embry and Klovan(1971), Boundstones in the sense of Dunham are subdivided into Bafflestones, Bindstones and Framestones. The term Boundstone "is retained for authochthonous limestones in which the specific mode of organic binding cannot be recognized" Lokier and Al Nunaibi(2016) define Boundstone as "an autochthonous carbonate-dominated rock in which there is any form of evidence that the original components were organically bound at the time of deposition; however, the mode of binding is not identifiable." In contrast to Embry and Klovan, they do not subdivide Boundstones into smaller classes. References {{Cite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
