Table 1.

Typical types of anthropogenic subsurface modifications, their depth of influence and associated material types

Subsurface modification typeDepth rangeTypical anthropogenic materials
Earthworks<10 m: basements, spread foundations, utility and sewerage networks;
>10 m–<150 m: piled foundations, deep basements, transportation networks
Brick, earthenware (pre-1950); concrete, plastic, geotextiles (post-1950); wire cables, steel
Boreholes and hydrocarbon wells>3 m–<100 m: ground investigation boreholes;
>15 m–<100 m: ground source heat pumps;
<12 300 m: scientific boreholes and hydrocarbon wells (e.g. Z-44 Chayvo well, Russia)
Steel casing, cement and grout; plastic casing/liners in monitoring wells; drilling muds, sand and gravel packing in uncased hydrocarbon wells
Tunnels and caverns<50 m: transportBrick or bolted cast iron segmental lining (pre-1950);
concrete lining (post-1950)
Waste and resource storage facilities>200–<1000 m: Geological Disposal Facility (GDF);
>800 m–<3000 m: Carbon Capture and Storage (CCS)
GDF: waste (possibly as glass), metal container (Cu or Pb), cement or bentonite plug or seal, backfill
Mineral workings<10 m: coal bell pits;
<30 m: coal pillar-and-stall;
>100–<1000 m: coal longwall mining;
<4000 m: gold mining
Props, corrugated iron shuttering and linings, stowed wastes
Weapon detonation<2850 m: nuclear detonation, e.g. Nefte-yugamsk, RussiaMelt of nuclear device and associated hardware and adjacent rock/ sediment