What is another common name for a Standard Parallel?

A Standard Parallel, also known as a Correction Line, is employed in land surveys primarily as part of the Public Land Survey System (PLSS). These lines are used to correct for the curvature of the Earth, which affects the shape and spacing of townships. As one moves north or south from the initial point of a survey, the Earth's curvature means that meridians converge, leading to discrepancies in plot size and shape.

To maintain accuracy across the surveyed area, Standard Parallels are established at specific intervals (usually every 24 miles) to adjust the north-south townships, ensuring that they remain uniform in size. The term "Correction Line" reflects their purpose of adjusting for these discrepancies in survey measurements.

The other options represent different concepts in surveying. A Base Line refers to the east-west line from which townships are measured, a Reference Line could pertain to various types of lines used for reference but is not a standard term in this context, and a Township Line is a boundary line between townships but does not serve the specific purpose of correcting for curvature. Understanding these distinctions clarifies why the term "Correction Line" accurately identifies a Standard Parallel within surveying practices.