Underground working

Today any kind of underground work (especially in hard rock) is very time consuming and energy extensive. With APM technology this may change radically. Astonishing cutting speeds should be possible.

With APM technology one could make cutting saw-blades that:

• are made from superhard refractory diamondoid materials
• are only some micrometers thin giving them high surface area relative to their volume and thus good self cooling properties
• are actively cooled with capsule transport allowing for even faster cutting
• can transport away micro debris also employing capsule transport
• regularely replace their cutting teeth (self repair)
• are driven by shearing drives

With such fancy saw blade system big sized chunks (e.g. liter to cubic meter) of soil could be cut out and transported to the surface in an infinitesimal beared state. For this to work the drill channel must have consistent cross secttion. It could be like a bore hole with low bending radius or a just a bunch of perfect cubes requiring full stops of motion at the micrometer sharp 90° turns due to the high inertial mass of the huge blocks.

Assuming a cut width of 1um and a core diameter or 1m (in square) the ratio between the preserved drill core volume and destroyed cut volume is (10⁶)²:1 or 10¹²:1 or 1 000 000 000 000 : 1 meaning that if you excavate one cubic kilometer of material you only irreversibly destroy one cubic meter the drilling cores drilling cores preserved

A high amount of energy is only required for lifting stuff up from very great depths. a vew hunded kilometers down the necessary energies are like the energies involved in spaceflight to LEO. One dont has to propell the propellant though.

Related

• deep drilling
• specifics to tunnel construction (tunelling)
• specifics to near surface excavation work
• geoengineering
• prospective work for mining deep mining