Core sample

Removed from the tube in the laboratory, it is inspected and analyzed by different techniques and equipment depending on the type of data desired.

Core samples can be taken to test the properties of manmade materials, such as concrete, ceramics, some metals and alloys, especially the softer ones.

Taking samples from an exposure, be it an overhanging rock face or on a different planet, is almost trivial.

Non-destructive techniques are increasingly common, e.g., the use of MRI scanning to characterize grains, pore fluids, pore spaces (porosity) and their interactions (constituting part of permeability) but such expensive subtlety is likely wasted on a core that has been shaken on an unsprung lorry for 300 km of dirt road.

Civil engineering or soil studies may have their own, different, conventions as their materials are often not competent enough to make permanent marks on.

It is becoming increasingly common to retain core samples in cylindrical packaging which forms part of the core-cutting equipment, and to make the marks of record on these "inner barrels" in the field prior to further processing and analysis in the laboratory.

A unit of length occasionally used in the literature on seabed cores is cmbsf, an abbreviation for centimeters below sea floor.

The value to oceanic and other geologic history of obtaining cores over a wide area of sea floors soon became apparent.

To date hundreds of thousands of core samples have been collected from floors of all the planet's oceans and many of its inland waters.

The dynamic phenomena of the Earth's surface are for the most part cyclical in a number of ways, especially temperature and rainfall.

For example, cores in the ocean floor, soil and ice have altered the view of the geologic history of the Pleistocene entirely.

If compressed air is used for cutting extraction the sample remains uncontaminated, is available almost immediately, and the method has a low environmental impact.