What is the purpose of core recovery?

The parameters like core recovery provide a clear understanding of the condition of the rock and it is an indication for deciding the extent of grouting etc. Further, RQD could be used as an indication to decide on rock quality.

What is core recovery ratio and RQD?

Rock quality designation (RQD) has several definitions. The most widely used definition was developed in 1964 by D. U. Deere. It is the borehole core recovery percentage incorporating only pieces of solid core that are longer than 100 mm in length measured along the centerline of the core.

What is core loss in drilling?

These core loss gaps result from difficulties with the drilling process, either due to poor ground conditions, or mechanical problems, and are therefore zones of potentially high economic and geotechnical risk.

What is RQD geology?

Rock quality designation (RQD) is a standard technique in the mining industry for the qualitative and quantitative assessment of rock quality and degree of jointing, fracturing, and shearing in a rock mass.

How do I check my core recovery?

Core Recovery and RQD (Rock Quality Designation) The easiest way to characterize the amount of material recovered during rock coring is to calculate “core recovery” as the amount (i.e. length) of recovered material divided by the total length of the core run (presented as a percentage).

What is total core recovery?

Definition. The total core recovery (TCR) is defined as the pro- portion of core recovered to the total length of the drilled run. The core run is the length reported by the driller as the actual depth penetrated.

How do I recover my core?

The easiest way to characterize the amount of material recovered during rock coring is to calculate “core recovery” as the amount (i.e. length) of recovered material divided by the total length of the core run (presented as a percentage).

What is NX core size?

● NX core: standard diameter = 54 mm. (2.15 inches) Core Barrels.

What is a core run?

Technically, the distance cored per round trip, which is expressed in number of feet or in relative terms, as short or long. Core blocks may occur before the core barrel is filled; the barrel then is short of being full, resulting in a short core run.

What is a core log?

Core logging is the systematic recording and measuring of as much information as possible/required to determine the lithology (rock types), mineralogy, potential geological history, structure and alteration zones through a tiny piece of cylindrical rock drilled and removed from a potential mineral deposit.

Is code a rock?

The strength of the intact rock material should be obtained from rock cores in accordance with IS 9143 or IS 8764 or IS 10785 as applicable based on site conditions. The ratings based on uniaxial compressive strength andpoint load strength aregiven in Annex B (Item I).