2 Flashcards
(30 cards)
What is a Spatial Reference Framework?
A combination of factors; ellipsoid, geoid, datum, coordinate system and projection that identify a point on a sphere and on a two dimensional representation of the sphere.
What is Geodesy?
The science of measuring the earth.
What is Surveying?
The science of identifying and measuring specific locations on the earth.
What is an Ellipsoid?
A mathematical model of the size and shape of the earth.
What is a Spheroid?
A slightly non-spherical mathematically definable object, but not necessarily.
What is a Geoid?
A theoretical surface generally defined as mean sea level. Used as the basis for a vertical datum and as a reference for a horizontal datum.
What is a Horizontal Datum?
A spheroid used as an (X, Y) reference to all points on the real globe.
What is a Vertical Datum?
Level surface to which heights (elevation) are referenced.
What is WGS84?
Worldwide ellipsoid and datum created from satellite observations.
What is the Luzon Datum of 1911?
The national horizontal datum for the Philippines.
What is PRS92?
Updated Luzon Datum of 1911.
What is a Projection?
A two-dimensional reference surface used to convert locations from a curved surface to a flat surface.
What is a Central Meridian?
Longitude line that the transverse Mercator projection is centered on.
What is a Scale Factor?
Number that is multiplied to northing and easting values to be placed on a two dimensional map.
What is UTM?
Universal Transverse Mercator coordinate system. A series of projections used worldwide. Designed for regional areas of study.
What is PTM?
Philippine Transverse Mercator coordinate system. Local series of projections designed primarily for collecting survey data in the Philippines.
What is Easting?
The X coordinates of a coordinate system used on a map.
What is Northing?
The Y coordinates of a coordinate system used on a map.
What is Foreshore land?
Refers to that part of the shore which is alternately covered and uncovered by the ebb and flow of the (equinoctial) tide.
What is a Shoreline?
Is the line along the sea coast reached by the highest equinoctial tide.
What is a Salvage Zone?
Is an easement of lands bordering the seas, gulfs, bays, or ports measured landward from the interior limit of the shoreline.
What is an Easement of Coast Police?
Is the obligation to leave a Right-of-Way Six (6) meters wide within the Salvage Zone.
What is a Buffer Zone?
Refers to a strip of land with natural or established vegetation which provides an added layer of protection to the natural forest including mangrove forests. This is usually between 50 to 100 meters measured from the shoreline and towards inland and includes the salvage zone.
What is an Arroyo?
Shall be a narrow natural bed or channel through which the water flows continuously or intermittently throughout the year.
