What are petrographic Services?
Traditional petrographic services typically involves the point counting of quartz, feldspar and lithic fragments together with the distribution of authigenic phases for reservoir quality and diagenetic studies. A more innovative approach developed by Chemostrat focuses on provenance-related petrography.
What is the meaning of petrographic?
Definition of petrography : the description and systematic classification of rocks.
What are petrographic characteristics?
The important petrographic characteristics influencing mechanical behaviour include modal concentration and grain size of individual minerals, mean grain size of rock and distribution of grain size within a rock. Recrystallization of minerals along boundaries has a pronounced effect on increased strength of granites.
How is petrography done?
Petrography is the study of rocks in thin section by means of a petrographic microscope (i.e., an instrument that employs polarized light that vibrates in a single plane). Petrography is primarily concerned with the systematic classification and precise description of rocks.
What are thin sections used for?
A thin section or petrographic thin section is a type of laboratory preparation commonly used in geology, minerology, or petrography. Typically, a thin section is used to analyze a sample of rock, mineral, pottery, soil, bone, or even a piece of metal.
How do you make thin sections of rocks?
Frail or crumbly specimens need to be hardened first by adding a resin that’s commonly used to fix soil samples. A thin sliver of the hardened or naturally hard rock is then cut off using a motorized diamond saw or hacksaw. Round rocks are cut using a drill with a tubular diamond grinding tool.
What is the difference between petrography and petrogenesis?
Petrography is a branch of petrology that focuses on the description and classification of rocks, especially by microscopic examination, while petrogenesis is a branch of petrology that focuses on the origin and formation of rocks, especially igneous rocks.
What is petrographic thin section?
In optical mineralogy and petrography, a thin section (or petrographic thin section) is a thin slice of a rock or mineral sample, prepared in a laboratory, for use with a polarizing petrographic microscope, electron microscope and electron microprobe.
How do you make a petrographic thin section?
A thin sliver of rock is cut from the sample with a diamond saw and ground optically flat. It is then mounted on a glass slide and then ground smooth using progressively finer abrasive grit until the sample is only 30 μm thick.
What is rock thin section?
A rock thin section is created by gluing a small piece of rock onto a glass slide, then grinding it down to a thickness of 30 microns (the average human hair is about 100 microns in diameter) so that light shines through it when examined under the microscope.