PLSS

Section

A one-square-mile (640-acre) unit of land within a PLSS township, numbered 1-36 in a serpentine pattern.

Detailed Definition

A section is a one-square-mile (640-acre) unit of land within a PLSS township. Each township contains 36 sections, numbered 1 through 36 in a serpentine pattern. Sections are the basic unit for mining claim legal descriptions on public lands.

Section characteristics: - Nominal size: 1 mile by 1 mile (640 acres) - Actual size may vary due to survey conditions, terrain, and convergence of meridians - Sections along the north and west edges of a township may be irregular (fractional sections) - Bounded by section lines and identified by section corners

Section numbering: Sections are numbered in a serpentine (boustrophedon) pattern within each township: - Section 1 is in the northeast corner - Numbering proceeds west across the top row (6, 5, 4, 3, 2, 1) - Then east across the next row (7, 8, 9, 10, 11, 12) - Alternating direction to Section 36 in the southeast corner

  • Quarter sections: 160 acres (NE/4, NW/4, SE/4, SW/4)
  • Quarter-quarter sections: 40 acres (e.g., NE/4 of NW/4)
  • Government lots: Irregular fractional parcels along township edges
  • Further subdivision to as small as 2.5 acres (quarter-quarter-quarter-quarter section)

Significance for mining claims: Mining claims are commonly described by their location within a section using aliquot parts (e.g., "NW/4 of NE/4 of Section 15, T3N, R5W"). Placer claims are typically located on aliquot part boundaries, while lode claims may use metes and bounds descriptions.