GISP-E Exam Questions &
Answers (Grade A+)
Georeferencing—ANSWER--associating a map or image with spatial locations
Control points—ANSWER--consisting of multiple points, points come in pairs that match the
spatial location with a point on an unreferenced image or map
Spatial reference system (SRS) or coordinate reference system (CRS)—ANSWER--a
coordinate-based local, regional, or global system used to locate geographical entities
International Terrestrial Reference System (ITRS)—ANSWER--Three-dimensional coordinate
system with a well-defined origin (the center of mass of the Earth) and three orthogonal
coordinate axes (X,Y,Z)
Map projection—ANSWER--transforming coordinate from a curved earth to a flat map
Horizontal datum—ANSWER--Model of the earth as a spheroid (2 components, reference
ellipsoid and a set of survey points both the shape of the spheroid and its position relative to
the earth
Vertical datum—ANSWER--reference points for elevations of surfaces and features on the
Earth - could be based on tidal, sea levels, gravimetric, based on a geoid
NAVD88—ANSWER--gravity based geodetic datum in North America
, Geodetic datum—ANSWER--set of control points whose geometric relationships are known,
either through measurements or calculation
WGS 84—ANSWER--World Geodetic System - reference coordinate system used by the
Global Positioning System (GPS)
SRID integer—ANSWER--spatial reference system id numbers, including EPSG codes defined
by the international Association of Oil and Gas Producers
4 distortions—ANSWER--Distance, Direction, Shape, and Area
Mercator Projection—ANSWER--Preserves shape and direction, area gets distorted -
projecting earth onto a cylinder tangent to a meridian
Azimuthal Equidistant—ANSWER--planar (tangent) - used for air route distances - distances
measured from the center are true - distortion of other properties increases away from the
center point
Cylindrical equal-area projections—ANSWER--preserves area, shape and distance gets
distorted near the upper and lower regions of the map - straight meridians and parallels -
meridians are equally spaced and the parallels are unequally spaced
Conic projections—ANSWER--preserves directions and areas in limited areas - distorts
distances and scale except along standard parallels - generated by projecting a spherical
surface onto a cone
Choosing a projections—ANSWER--Latitude - low-latitude areas (near equator) use a conical
projections, Polar regions use an Azimuthal planar projection
© 2026 Copyright. All Rights Reserved. This document is
protected by copyright law, Copyrighted By Brittie Donald
Answers (Grade A+)
Georeferencing—ANSWER--associating a map or image with spatial locations
Control points—ANSWER--consisting of multiple points, points come in pairs that match the
spatial location with a point on an unreferenced image or map
Spatial reference system (SRS) or coordinate reference system (CRS)—ANSWER--a
coordinate-based local, regional, or global system used to locate geographical entities
International Terrestrial Reference System (ITRS)—ANSWER--Three-dimensional coordinate
system with a well-defined origin (the center of mass of the Earth) and three orthogonal
coordinate axes (X,Y,Z)
Map projection—ANSWER--transforming coordinate from a curved earth to a flat map
Horizontal datum—ANSWER--Model of the earth as a spheroid (2 components, reference
ellipsoid and a set of survey points both the shape of the spheroid and its position relative to
the earth
Vertical datum—ANSWER--reference points for elevations of surfaces and features on the
Earth - could be based on tidal, sea levels, gravimetric, based on a geoid
NAVD88—ANSWER--gravity based geodetic datum in North America
, Geodetic datum—ANSWER--set of control points whose geometric relationships are known,
either through measurements or calculation
WGS 84—ANSWER--World Geodetic System - reference coordinate system used by the
Global Positioning System (GPS)
SRID integer—ANSWER--spatial reference system id numbers, including EPSG codes defined
by the international Association of Oil and Gas Producers
4 distortions—ANSWER--Distance, Direction, Shape, and Area
Mercator Projection—ANSWER--Preserves shape and direction, area gets distorted -
projecting earth onto a cylinder tangent to a meridian
Azimuthal Equidistant—ANSWER--planar (tangent) - used for air route distances - distances
measured from the center are true - distortion of other properties increases away from the
center point
Cylindrical equal-area projections—ANSWER--preserves area, shape and distance gets
distorted near the upper and lower regions of the map - straight meridians and parallels -
meridians are equally spaced and the parallels are unequally spaced
Conic projections—ANSWER--preserves directions and areas in limited areas - distorts
distances and scale except along standard parallels - generated by projecting a spherical
surface onto a cone
Choosing a projections—ANSWER--Latitude - low-latitude areas (near equator) use a conical
projections, Polar regions use an Azimuthal planar projection
© 2026 Copyright. All Rights Reserved. This document is
protected by copyright law, Copyrighted By Brittie Donald
