FGDC-STD-014.3-2008

Geographic Information Framework Data Content 

Standard 

Part 3: Elevation 

May 2008 
ii

Federal Geographic Data Committee 

Established by Office of Management and Budget Circular A-16, the Federal Geographic Data 

Committee (FGDC) promotes the coordinated development, use, sharing, and dissemination of 

geographic data. 

The FGDC is composed of representatives from the Departments of Agriculture, Commerce, 

Defense, Education, Energy, Health and Human Services, Homeland Security, Housing and 

Urban Development, the Interior, Justice, Labor, State, and Transportation, the Treasury, and 

Veteran Affairs; the Environmental Protection Agency; the Federal Communications Commission; 

the General Services Administration; the Library of Congress; the National Aeronautics and 

Space Administration; the National Archives and Records Administration; the National Science 

Foundation; the Nuclear Regulatory Commission; the Office of Personnel Management; the Small 

Business Administration; the Smithsonian Institution; the Social Security Administration; the 

Tennessee Valley Authority; and the U.S. Agency for International Development. 

Additional Federal agencies participate on FGDC subcommittees and working groups. The 

Department of the Interior chairs the committee. 

FGDC subcommittees work on issues related to data categories coordinated under the circular. 

Subcommittees establish and implement standards for data content, quality, and transfer; 

encourage the exchange of information and the transfer of data; and organize the collection of 

geographic data to reduce duplication of effort. Working groups are established for issues that 

transcend data categories. 

For more information about the committee, or to be added to the committee's newsletter mailing 

list, please contact: 

 

Federal Geographic Data Committee Secretariat 

c/o U.S. Geological Survey 

590 National Center 

Reston, Virginia 22092 

Facsimile: (703) 648-5755 

Internet (electronic mail): fgdc@usgs.gov 

 World Wide Web: http://www.fgdc.gov
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation

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Contents 

Introduction.................................................................................................................................. vii

1 Scope, purpose, and application .............................................................................................. 1

2 Conformance............................................................................................................................... 1

3 Normative references................................................................................................................. 1

4 Maintenance authority ............................................................................................................... 1

4.1 Level of responsibility...................................................................................................... 1

4.2 Contact information ......................................................................................................... 1

5 Terms and definitions ................................................................................................................ 2

6 Symbols, abbreviated terms, and notations............................................................................ 4

7 Requirements.............................................................................................................................. 4

7.1 General .............................................................................................................................. 4

7.2 Point................................................................................................................................... 4

7.3 Grid .................................................................................................................................... 5

7.4 Contour.............................................................................................................................. 6

7.5 Triangulated irregular network (TIN) .............................................................................. 7

7.6 Profile................................................................................................................................. 7

Annex A (normative) UML model, Application schema for the exchange of framework 

elevation data............................................................................................................................... 10

A.1 General ............................................................................................................................ 10

A.2 ElevationCollection ........................................................................................................ 10

A.2.1 Semantics........................................................................................................................ 10

A.2.2 extent ............................................................................................................................... 10

A.2.3 metadata.......................................................................................................................... 11

A.2.4 gridSet ............................................................................................................................. 11

A.2.5 pointSet ........................................................................................................................... 11

A.2.6 pointCoverage................................................................................................................. 11

A.2.7 contourSet....................................................................................................................... 11

A.2.8 tin ..................................................................................................................................... 11

A.2.9 profileSet ......................................................................................................................... 11

A.3 ElevationCoverage ......................................................................................................... 12

A.3.1 Semantics........................................................................................................................ 12

A.3.2 domainExtent.................................................................................................................. 12

A.3.3 rangeType........................................................................................................................ 13

A.3.4 commonPointRule.......................................................................................................... 13

A.3.5 metadata.......................................................................................................................... 13

A.4 ElevationGridCoverage.................................................................................................. 14

A.4.1 Semantics........................................................................................................................ 14

A.4.2 interpolationType ........................................................................................................... 14

A.4.3 data .................................................................................................................................. 14

A.5 ElevationGrid .................................................................................................................. 15

A.5.1 Semantics........................................................................................................................ 15

A.5.2 dimension........................................................................................................................ 15

A.5.3 axisNames....................................................................................................................... 15

A.5.4 origin................................................................................................................................ 15

A.5.5 offsetVectors................................................................................................................... 15
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Part 3: Elevation

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A.5.6 extent ............................................................................................................................... 15

A.5.7 sequencingRule.............................................................................................................. 15

A.5.8 startSequence................................................................................................................. 15

A.5.9 values............................................................................................................................... 15

A.6 ElevationPointCoverage ................................................................................................ 16

A.6.1 Semantics........................................................................................................................ 16

A.6.2 element ............................................................................................................................ 16

A.7 MultiElevationPoint ........................................................................................................ 16

A.7.1 Semantics........................................................................................................................ 16

A.7.2 geometry.......................................................................................................................... 16

A.7.3 value................................................................................................................................. 17

A.8 ElevationTinCoverage.................................................................................................... 17

A.8.1 Semantics........................................................................................................................ 17

A.8.2 interpolationType ........................................................................................................... 17

A.8.3 geometry.......................................................................................................................... 18

A.8.4 element ............................................................................................................................ 18

A.9 ElevationTriangle............................................................................................................ 18

A.9.1 geometry.......................................................................................................................... 18

A.9.2 collection......................................................................................................................... 18

A.9.3 control value ................................................................................................................... 18

A.9.4 MultiElevationPoint ........................................................................................................ 18

A.10 ElevationContourCoverage ........................................................................................... 19

A.10.1 Semantics ................................................................................................................... 19

A.10.2 element........................................................................................................................ 19

A.11 ElevationContour............................................................................................................ 19

A.11.1 Semantics ................................................................................................................... 19

A.11.2 geometry ..................................................................................................................... 20

A.11.3 value ............................................................................................................................ 20

A.12 ElevationPointSet ........................................................................................................... 20

A.12.1 Semantics ................................................................................................................... 20

A.12.2 domainExtent.............................................................................................................. 20

A.12.3 point............................................................................................................................. 20

A.12.4 metadata...................................................................................................................... 21

A.13 ElevationPoint................................................................................................................. 21

A.13.1 Semantics ................................................................................................................... 21

A.13.2 surfaceType ................................................................................................................ 21

A.13.3 geometry ..................................................................................................................... 21

A.14 ElevationProfileCollection............................................................................................. 21

A.14.1 Semantics ................................................................................................................... 21

A.14.2 domainExtent.............................................................................................................. 22

A.14.3 metadata...................................................................................................................... 22

A.14.4 profile .......................................................................................................................... 22

A.15 ElevationProfile .............................................................................................................. 22

A.15.1 Semantics ................................................................................................................... 22

A.15.2 surfaceType ................................................................................................................ 22

A.15.3 profileType.................................................................................................................. 22

A.15.4 geometry ..................................................................................................................... 22

A.16 DirectPosition ................................................................................................................. 23

A.16.1 Semantics ................................................................................................................... 23

A.16.2 coordinate................................................................................................................... 23

A.16.3 dimension ................................................................................................................... 23

A.16.4 coordinateReferenceSystem..................................................................................... 24

A.17 Code lists......................................................................................................................... 24

A.17.1 CV_CommonPointRule code list .............................................................................. 24

A.17.2 CV_InterpolationMethod code list............................................................................ 25
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A.17.3 CV_SequenceType code list ..................................................................................... 25

A.17.4 ProfileType code list .................................................................................................. 26

Annex B (normative) Elevation data UML object description, Data dictionaries for 

framework elevation data ........................................................................................................... 27

B.1 ElevationCollection ........................................................................................................ 27

B.2 ElevationCoverage ......................................................................................................... 28

B.3 ElevationGridCoverage.................................................................................................. 29

B.4 ElevationPointCoverage ................................................................................................ 32

B.5 ElevationTinCoverage.................................................................................................... 33

B.6 ElevationContourCoverage ........................................................................................... 34

B.7 ElevationPointSet ........................................................................................................... 35

B.8 ElevationProfileCollection............................................................................................. 36

Annex C (informative) Bibliography .......................................................................................... 37

Figures 

Figure 1 – Elevation....................................................................................................................... 4

Figure 2 – Example: Point............................................................................................................. 5

Figure 3 – Example: Grid .............................................................................................................. 6

Figure 4 – Example: Contours...................................................................................................... 6

Figure 5 – Example: Triangulated irregular network ................................................................. 7

Figure 6 – Example: Profile1 ........................................................................................................ 8

Figure 7 – Example: Profile2 ........................................................................................................ 8

Figure 8 – Example: Profile3 ........................................................................................................ 9 

Figure A.1 – ElevationCollection................................................................................................ 10

Figure A.2 – ElevationCoverage................................................................................................. 12

Figure A.3 – ElevationGridCoverage ......................................................................................... 14

Figure A.4 – ElevationPointCoverage ....................................................................................... 16

Figure A.5 – ElevationTinCoverage ........................................................................................... 17

Figure A.6 – ElevationContourCoverage .................................................................................. 19

Figure A.7 – ElevationPointSet .................................................................................................. 20

Figure A.8 – ElevationProfileCollection .................................................................................... 21

Figure A.9 – DirectPosition......................................................................................................... 23

Figure A.10 – Code lists.............................................................................................................. 24

Tables 

Table A.1 – CodeList for CV_CommonPointRule..................................................................... 24

Table A.2 – CodeList for CV_InterpolationMethod................................................................... 25

Table A.3 – CodeList for CV_SequenceType............................................................................ 25

Table A.4 – Codelist for ProfileType.......................................................................................... 26 

Table B.1 – Data dictionary for ElevationCollection ................................................................ 27

Table B.2 – Data dictionary for ElevationCoverage ................................................................. 28

Table B.3 – Data dictionary for ElevationGridCoverage.......................................................... 29

Table B.4 – Data dictionary for ElevationPointCoverage ........................................................ 32

Table B.5 – Data dictionary for ElevationTinCoverage............................................................ 33

Table B.6 – Data dictionary for ElevationContourCoverage ................................................... 34

Table B.7 – Data dictionary for ElevationPointSet................................................................... 35

Table B.8 – Data dictionary for ElevationProfileCollection..................................................... 36
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation

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Foreword 

Geographic information, also known as geospatial information, both underlies and is the subject 

of much of the political, economic, environmental, and security activities of the United States. In 

recognition of this, the United States Office of Management and Budget issued Circular A-16 

(revised 2002), which established the Federal Geographic Data Committee (FGDC) as a 

coordinating organization. 

Work on this standard started under the Geospatial One-Stop e-Government initiative. The 

standard was developed with the support of the member agencies and organizations of the 

FGDC and aids in fulfilling a primary objective of the National Spatial Data Infrastructure (NSDI), 

that is, creation of common geographic base data for seven critical data themes. The seven core 

data themes are considered framework data of critical importance to the spatial data 

infrastructure. 

As the Geographic Information Framework Data Content Standard was developed using public 

funds, the U.S. Government will be free to publish and distribute its contents to the public, as 

provided through the Freedom of Information Act (FOIA), Part 5 United States Code, Section 552, 

as amended by Public Law No. 104-231, “Electronic Freedom of Information Act Amendments of 

1996”. 
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation

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Introduction 

The primary purpose of this part of the Geospatial Information Framework Data Ccontent 

Standard is to describe content of geospatial elevation data models to support of the exchange of 

elevation information. This part seeks to establish a common baseline for the semantic content of 

elevation databases for public agencies and private enterprises. It also seeks to decrease the 

costs and simplify the exchange of elevation data among local, Tribal, State, and Federal users 

and producers. That, in turn, discourages duplicative data collection. Benefits of adopting this 

part of the standard also include the long-term improvement of the geospatial elevation data 

within the community. 
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation

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1 Scope, purpose, and application 

The Elevation part of the Framework Data Content Standard defines the geospatial data model 

entities and attributes that permit the exchange of digital elevation data consistent with the 

National Spatial Data Infrastructure’s (NSDI) framework for elevation data. This part of the 

standard is consistent with ISO 19123 Geographic Information – Schema for Coverage Geometry 

and Functions and the OGC 03-065r6 Abstract Specification for Coverage Type and its Subtypes. 

The part includes an application schema expressed in the Unified Modeling Language (UML). 

The Elevation part identifies the geospatial data model elements required for digital elevation data 

to be used for the NSDI framework. The part was written to be inclusive of the common 

geospatial elevation data models (point, grid, contour, triangulated irregular network, and profile) 

and to not restrict anyone wishing to contribute their elevation data to the NSDI. The part 

supports both topographic elevation data (above a reference datum) and bathymetric elevation 

data (below a reference datum). Collecting and sharing NSDI digital elevation data that are 

consistent with this part of the standard will assure a common understanding of the data 

throughout the user community. Furthermore, the principles described in this standard may be 

extended to other geographic entities to facilitate the exchange of other geospatial thematic data. 

2 Conformance 

Each geospatial elevation model of the Elevation part includes a data dictionary based on the 

conceptual application schema presented in that model. To conform to this part of the 

Framework Data Content Standard, an elevation dataset shall satisfy the requirements of the 

data dictionary for that geospatial data model. 

3 Normative references 

Annex A of the Base Document (Part 0) lists normative references applicable to two or more parts 

of the standard. Informative references applicable only to the Elevation part are listed in Annex 

C. Annex D of the Base Document lists informative references applicable to two or more of the 

parts. 

4 Maintenance authority 

4.1 Level of responsibility 

The FGDC is the responsible organization for coordinating work on all parts of the Geographic 

Information Framework Data Content Standard. The U.S. Department of the Interior, United 

States Geological Survey (USGS), National Geospatial Programs Office, working with the FGDC, 

is directly responsible for development and maintenance of the Geographic Information 

Framework Data Content Standard, Part 3: Elevation. 

4.2 Contact information 

Address questions concerning this part of the standard to: 

Federal Geographic Data Committee Secretariat 

c/o U.S. Geological Survey 

590 National Center 

Reston, Virginia 20192 USA 

Telephone: (703) 648-5514 

Facsimile: (703) 648-5755 

Internet (electronic mail): gdc@fgdc.gov

WWW Home Page: http://fgdc.gov

Or 
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation

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Associate Director for Geographic Information 

United States Geological Survey, MS 108 

12201 Sunrise Valley Drive 

Reston, VA 20192 

Telephone: (703) 648-5747 

Facsimile: (703) 648-7031 

5 Terms and definitions 

Definitions applicable to the Elevation part are listed below. More general terms and definitions 

can be found in the Base Document (Part 0). Users are advised to consult that part for a 

complete set of definitions. 

5.1 

coordinate reference system 

coordinate system which is related to the real world by a datum [ISO 19111] 

5.2 

coverage 

feature that acts as a function to return values from its range for any direct position within its 

spatial, temporal, or spatiotemporal domain [ISO 19123] 

EXAMPLES A raster image, a polygon overlay, or a digital elevation matrix. 

5.3 

coverage geometry 

configuration of the domain of a coverage described in terms of coordinates [ISO 19123] 

5.4 

direct position 

position described by a single set of coordinates within a coordinate reference system [ISO 

19107] 

5.5 

elevation 

distance measured upward along a plumb line between a point and the geoid 

NOTE The elevation of a point is normally the same as its orthometric height. This is the “official” 

geodesy definition of elevation, but the term “elevation” is also used more generally for height above a 

specific vertical reference, not always the geoid. 

5.6 

geometry value pair 

ordered pair composed of a spatial object, a temporal object, or a spatiotemporal object and a 

record of feature attribute values [ISO 19123] 

5.7 

grid 

network composed of two or more sets of curves in which the members of each set intersect the 

members of the other sets in an algorithmic way [ISO 19123] 

NOTE The curves partition a space into grid cells. 
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5.8 

line segment 

straight line between two points 

5.9 

point coverage 

coverage that has a domain composed of points [ISO 19123] 

5.10 

range 

set of feature attribute values associated by a function with the elements of the domain of a 

coverage 

5.11 

record 

finite, named collection of related items (objects or values) [ISO 19107] 

NOTE Logically, a record is a set of pairs <name, item>. 

5.12 

spatial object 

object used for representing a spatial characteristic of a feature [ISO 19107] 

5.13 

tessellation 

partitioning of a space into a set of conterminous spatial object, temporal object, or 

spatiotemporal object having the same dimension as the space being partitioned [ISO 19123] 

NOTE A tessellation composed of congruent regular polygons or polyhedra is a regular tessellation. 

One composed of regular, but non-congruent polygons or polyhedra is a semi-regular tessellation. 

Otherwise the tessellation is irregular. 

5.14 

triangulated irregular network 

TIN 

tessellation composed of triangles [ISO 19123] 

5.15 

vector 

quantity having direction as well as magnitude [ISO 19123] 

NOTE A directed line segment represents a vector if the length and direction of the line segment are 

equal to the magnitude and direction of the vector. The term vector data refers to data that represents the 

spatial configuration of features as a set of directed line segments. 
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Part 3: Elevation

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6 Symbols, abbreviated terms, and notations 

The following symbols, abbreviations, and notations are applicable to the Elevation part. 

Symbols, abbreviated terms, and notations applicable to multiple parts are listed in the Base 

Document (Part 0). 

3D – 3-dimensional 

LIDAR – Light Detection and Ranging 

TIN – Triangulated Irregular Network 

7 Requirements 

7.1 General 

This standard models elevation data as a geospatial data coverage within the context of five 

geospatial data models: Point, Grid, TIN, Contour, and Profile as shown in Figure 1. 

Specifications, defined in this standard, accommodate the level of content and relationships 

necessary for exchange of all forms and formats of these data in a predictable and repeatable 

manner. 

Figure 1 – Elevation 

Definitions for, and characteristics of, digital elevation data may be specific to these individual 

data models, or they may apply to all five geospatial data models. Appendix B provides the 

application schema for each of these geospatial elevation data models. The National Digital 

Elevation Program (www.ndep.gov) has developed a set of Guidelines for Digital Elevation Data 

that describe and provide best practices and examples for each of these geospatial data models. 

7.2 Point 

Points are the most basic geospatial elevation data model used for modeling terrain and 

bathymetric elevation data. Points are usually represented by a collection of irregularly, or nonuniformly organized geometry coordinate sets as shown in Figure 2. Each point is identified by a 

horizontal coordinate geometry pair (X,Y) and an vertical coordinate elevation value (Z). The 

elevation value (Z) may be explicitly encoded as a triplet (X, Y, Z), known as an ElevationPointSet 

Elevation 

Point 

(Section 7.2) 

Grid 

(Section 7.3) 

Contour 

(Section 7.4) 

TIN 

(Section 7.5) 

Profile 

(Section 7.6) 
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Geographic Information Framework Data Content Standard 

Part 3: Elevation

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(see section A.12 for the ElevationPointSet UML application schema and B.7 for the 

ElevationPointSet UML object description) or as an attribute value to the X,Y geometry pair, 

known as an ElevationPointCoverage (see section A.6 for the ElevationPointCoverage UML 

application schema and B.4 for the ElevationPointCoverage UML object description). Point 

coverage attribution could include identification such as a control point reference, reference to the 

type of surface to which the point applies, or other characteristics specific to the point. The order 

(if applicable) and definition of these additional attributes shall be specified in the metadata. 

While points are not necessarily presented in a uniform or structured pattern, they often are 

acquired in a systematic distribution, which is intended to facilitate accurate representation of the 

surface or features the data are intended to model. When generated manually, points are ideally 

chosen so that subtle terrain characteristics, such as gradual variations in slope or aspect, or 

distinct features such as a levee or river embankment are adequately represented in the data. 

However, when generated automatically, such as through the use of an active sensing system 

(LIDAR), point distribution depends upon the characteristics of the sensor used to acquire the 

data, and its performance in different terrain and land cover types. 

Figure 2 – Example: Point 

7.3 Grid 

Grids are the most common geospatial data model used for modeling terrain and bathymetric 

elevation data. Grids are represented by a collection of regularly or uniformly organized points as 

shown in Figure 3. There are several advantages to grids over other types of elevation 

geospatial data models. A regular spacing of elevations requires that only one point be 

referenced to a horizontal coordinate. From this point, in conjunction with coordinate referencing 

information supplied with the grid, the horizontal location of all other points can be determined. 

This eliminates the need to explicitly define the horizontal geometry coordinate pairs of each 

elevation and minimizes file size. The grid is also an efficient structure for data processing. See 

section A.4 for the ElevationGridCoverage UML application schema and B.3 for the 

ElevationGridCoverage UML object description. 

The spacing within the grid can be chosen to most efficiently represent the size and frequency of 

terrain undulations to be modeled. For example, rough or dissected terrain may require small, 

Point 2

Point 1

Point 5

Point 7

Point 4

Point 6

Point 8

Point 3
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation

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narrow grid spacing, while gentle relief may be adequately modeled with fairly wide grid spacing. 

Grids may not model all terrain features smaller or narrower than the grid spacing when the 

feature lies between grid points. 

Figure 3 – Example: Grid 

7.4 Contour 

Three-dimensional vector modeling supports the exchange of constant-elevation features, also 

referred to as hypsography or contours. See section A.10 for the ElevationContourCoverage 

UML application schema and B.6 for the ElevationContourCoverage UML object description. 

Contours are vectors connecting points of equal elevation and are a common visual 

representation of topography and bathymetry in mapping applications as shown in Figure 4. The 

density of x, y coordinate geometry pairs (vertices) along a contour vector are dependent on the 

characteristics and complexity of the terrain. 

Figure 4 – Example: Contours 
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Geographic Information Framework Data Content Standard 

Part 3: Elevation

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7.5 Triangulated irregular network (TIN) 

A fundamental data structure frequently used to model points from photogrammetry and LIDAR 

collection is the triangulated irregular network (TIN). TINs are surface representations derived 

from irregularly spaced sample points and breakline features (surface discontinuities such as 

peaks, pits, ridges, and valleys). The main components of a TIN are nodes, edges, and triangles, 

which are linked by topological structure. TIN datasets include topological relationships between 

points and their neighboring triangles. Each sample point has an x,y coordinate geometry pair 

and a surface, or z-value. These points are connected by edges to form a set of non-overlapping 

triangles used to represent the surface as shown in Figure 5. See section A.8 for the 

ElevationTINCoverage UML application schema and B.5 for the ElevationTINCoverage UML 

object description. 

TINs are used many times when it is necessary to capture or show complex topographic 

elevation surfaces. TINs allow for extra data in complex areas and less data in non-complex 

areas and enable the use of natural topographic features as breaklines. See Figure 5 for an 

example of a triangulated irregular network. 

Figure 5 – Example: Triangulated irregular network 

7.6 Profile 

Profiles, also known as breaklines or cross sections (also referred to as transects), are lines that 

connect irregularly spaced points of varying elevation values as shown in Figure 6. Profiles are 

commonly used to model surface discontinuities such as peaks, pits, ridges, and valleys or may 

be used to model the elevation information of other linear features such as transportation or 

pipelines. See section A.15 for the ElevationProfile UML application schema and B.8 for the 

ElevationProfileCollection UML object description. 

They are used for specialized applications to represent a string of elevations along a designated 

path. Cross sections, which are generally perpendicular to a linear terrain feature, are used for a 

variety of engineering applications. For example, a cross section of a stream will show the 

stream channel geometry above and below the water surface for hydraulic engineering purposes 

and a cross section of a road will show the shape of the road surface including its crown, 

shoulders, and ditches. 
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Part 3: Elevation

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Breaklines are lines that are used to model a relatively abrupt change in the slope or continuity of 

a surface slope or aspect. Breaklines may represent surface breaks observed at a constant 

elevation or that trend up and down slope. 

Figure 6 – Example: Profile1 

Figure 7 – Example: Profile2 
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation

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Figure 8 – Example: Profile3
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation 

Annex A (normative): UML model, Application schema

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Annex A 

(normative) 

UML model, 

Application schema for the exchange of framework elevation 

data 

A.1 General 

The model object names and notation conform to the names and notation used by ISO Technical 

Committee 211 - Geographic information/Geomatics. 

A.2 ElevationCollection 

Figure A.1 – ElevationCollection 

A.2.1 Semantics 

The class ElevationCollection represents a collection of framework elevation data. It inherits the 

attribute metadata from the FeatureCollection class specified in the Base Document (Part 0). 

A.2.2 extent 

The attribute extent shall describe the geographic area to which the data in the 

ElevationCollection applies. The data type EX_GeographicExtent is specified in ISO 19115. 
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation 

Annex A (normative): UML model, Application schema

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A.2.3 metadata 

The attribute metadata shall provide a link to metadata that describes the ElevationCollection. 

A.2.4 gridSet 

The role name gridSet shall identify the set of ElevationGridCoverages contained in the 

ElevationCollection. 

A.2.5 pointSet 

The role name pointSet shall identify the set of ElevationPointSets contained in the 

ElevationCollection. 

A.2.6 pointCoverage 

The role name pointCoverage shall identify the set of ElevationPointCoverages contained in the 

ElevationCollection. 

A.2.7 contourSet 

The role name contourSet shall identify the set of ElevationContourCoverages contained in the 

ElevationCollection. 

A.2.8 tin 

The role name tin shall identify the set of ElevationTinCoverages contained in the 

ElevationCollection. 

A.2.9 profileSet 

The role name profileSet shall identify the set of ElevationProfileCollections contained in the 

ElevationCollection. 
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation 

Annex A (normative): UML model, Application schema

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A.3 ElevationCoverage 

Figure A.2 – ElevationCoverage 

A.3.1 Semantics 

ElevationCoverage is an abstract class that specifies a set of attributes common to all the kinds of 

coverages that may be contained in an ElevationCollection. It is a realization of the Type 

CV_Coverage specified in ISO 19123 and implements attributes specified for that Type. It 

inherits an association to SC_CRS from CV_Coverage. SC_CRS provides a description of the 

coordinate reference system including horizontal and vertical datums and units of measure. 

A.3.2 domainExtent 

The attribute domainExtent shall describe the spatial extent of the domain of the 

ElevationCoverage. 
Federal Geographic Data Committee FGDC-STD-014.3-2008 

Geographic Information Framework Data Content Standard 

Part 3: Elevation 

Annex A (normative): UML model, Application schema

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A.3.3 rangeType 

The attribute rangeType shall describe the range of the ElevationCoverage. It uses the data type 

RecordType specified in ISO/TS 19103. An instance of RecordType is a list of name:data type 

pairs each of which describes an attribute type included in the range of the coverage. The name 

field shall be used to identify the type of surface that each elevation value describes. 

EXAMPLE The rangeType for an elevation coverage that includes values for bare earth surface elevation 

and for reflective surface elevation would have the value “bare earth surface elevation:Real, reflective 

surface elevation:Real”. 

A.3.4 commonPointRule 

The attribute commonPointRule shall identify the procedure recommended for evaluating the 

ElevationCoverage at a position that falls on a boundary between geometric objects in the 

domain of the coverage. It takes a value from the code list CV_CommonPointRule specified in 

ISO 19123. The rule shall be applied to the set of elevation values that results from evaluating 

the coverage with respect to each of the geometric objects that share a boundary. For elevation 

coverages, appropriate values of CV_CommonPointRule include “average”, “high”, and “low”. 

A.3.5 metadata 

The attribute metadata shall provide a link to metadata that describes the ElevationCoverage. 
Federal Geographic Data Committee FGDC-STD-014.3-2008 

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A.4 ElevationGridCoverage 

Figure A.3 – ElevationGridCoverage 

A.4.1 Semantics 

The class ElevationGridCoverage is a subclass of ElevationCoverage that represents a set of 

elevation values assigned to the points in a 2D grid. The class is a realization of the Type 

CV_ContinuousQuadrilateralGridCoverage specified in ISO 19123 and implements the attributes 

and associations specified for that Type as well as those inherited from ElevationCoverage. 

A.4.2 interpolationType 

The attribute interpolationType shall specify the interpolation method recommended for 

evaluation of the ElevationGridCoverage. The data type CV_InterpolationMethod is a code list 

specified in ISO 19123. For an ElevationGridCoverage, the value shall be either “bilinear” or 

“bicubic”. 

A.4.3 data 

The role name data shall identify the ElevationGrid that contains the values of the 

ElevationGridCoverage. 
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A.5 ElevationGrid 

A.5.1 Semantics 

The class ElevationGrid represents the data content of an ElevationGridCoverage. It is a 

realization of two Types specified in ISO 19123: CV_RectifiedGrid and CV_GridValuesMatrix. As 

such, it implements the attributes of both of these Types. 

A.5.2 dimension 

The attribute dimension shall specify the dimension of the ElevationGrid. Its value shall be two 

for all instances of ElevationGrid. 

A.5.3 axisNames 

The attribute axisNames shall list the names of the grid axes, one of each dimension of the grid. 

EXAMPLES “north”, “east” or “latitude”, “longitude”. 

A.5.4 origin 

The attribute origin shall provide the coordinates of the grid origin with respect to an external 

coordinate reference system. The data type DirectPosition, specified in ISO 19107, has an 

association though the role name coordinateReferenceSystem to the class SC_CRS specified in 

ISO 19111. This association shall be used to identify the external coordinate reference system 

for the ElevationGrid. The external coordinate reference system for the ElevationGrid shall be the 

coordinate reference system identified by the association from ElevationCoverage to SC_CRS. 

A.5.5 offsetVectors 

The attribute offsetVectors shall specify both the spacing between grid points and the orientation 

of the grid axes with respect to the external coordinate reference system identified through the 

attribute origin. It uses the data type Vector specified in ISO/TS 19103. 

A.5.6 extent 

The attribute extent shall identify the area of the grid for which elevation data are provided. It 

uses the data type CV_GridEnvelope specified in ISO 19123 to provide both the 

CV_GridCoordinates of the corner of that area having the lowest grid coordinate values and the 

CV_GridCoordinates of the corner of that area having the highest grid coordinate values. 

CV_GridCoordinate is also specified in ISO 19123. 

A.5.7 sequencingRule 

The attribute sequencingRule shall identify the method to be used to assign values from the 

sequence of elevation values to grid coordinates. It uses the data type CV_SequenceRule 

specified in ISO 19123. 

A.5.8 startSequence 

The attribute startSequence shall use a value of CV_GridCoordinate to specify the grid 

coordinates of the grid point to which the first in the sequence of elevation values is to be 

assigned. 

A.5.9 values 

The role name values shall identify a sequence of Records each containing one or more elevation 

values to be assigned to a single grid point. Each Record shall conform to the RecordType 

specified by the rangeType attribute of the ElevationGridCoverage with which the ElevationGrid is 

associated. 
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A.6 ElevationPointCoverage 

Figure A.4 – ElevationPointCoverage 

A.6.1 Semantics 

The class ElevationPointCoverage is a subclass of ElevationCoverage and a realization of the 

Type CV_DiscretePointCoverage specified in ISO 19123. It is an aggregation of points, each of 

which is associated with one or more elevation values carried as attributes rather than as 

coordinates. It implements the attributes and associations inherited from ElevationCoverage as 

well as those specified for CV_DiscretePointCoverage in ISO 19123. 

A.6.2 element 

The role name element shall identify the set of MultiElevationPoints contained in the 

ElevationPointCoverage. 

A.7 MultiElevationPoint 

A.7.1 Semantics 

The class MultiElevationPoint is a realization of the Type CV_PointValuePair specified in ISO 

19123. It represents a point that has a Record of one or more elevation values associated with it. 

A.7.2 geometry 

The attribute geometry shall contain an instance of GM_Point as specified in ISO 19107. The 

position of the GM_Point shall be stated with reference to a 2-dimensional coordinate reference 

system. 

NOTE Elevation values are carried as attributes of the point rather than as coordinate values. 
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A.7.3 value 

The attribute value shall be a Record that contains one or more elevation values as specified by 

the rangeType attribute inherited from ElevationCoverage. 

A.8 ElevationTinCoverage 

Figure A.5 – ElevationTinCoverage 

A.8.1 Semantics 

The class ElevationTinCoverage is a realization of the Type CV_TinCoverage specified in ISO 

19123. It is an aggregation of ElevationTriangles that represents a triangulated irregular network 

in which the points of known elevation fall on the vertices of the triangles. It is also a subclass of 

ElevationCoverage that inherits the attributes specified for that class. 

A.8.2 interpolationType 

The attribute interpolationType shall specify the interpolation method recommended for 

evaluation of the ElevationTinCoverage. The data type CV_InterpolationMethod is a code list 

specified in ISO 19123. For an ElevationTinCoverage, the value shall be “barycentric”. 
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A.8.3 geometry 

The attribute geometry shall contain the network of triangles that form the basis of the TIN. The 

class GM_Tin is specified in ISO 19107. The triangles shall lie on a 2-dimensional surface; the 

elevation values at the vertices are treated as attributes of the points, not as coordinate values. 

A.8.4 element 

The role name element shall identify the set of ElevationTriangles contained in the 

ElevationTinCoverage. 

A.9 ElevationTriangle 

The class ElevationTriangle is a realization of the Type CV_ValueTriangle specified in ISO 

19123. It represents one of the triangles of the TIN and the elevation values associated with the 

vertices of that triangle. 

A.9.1 geometry 

The attribute geometry shall contain the GM_Triangle that is the basis of the ElevationTriangle. 

The class GM_Triangle is specified in ISO 19107. Each instance of geometry is an instance of 

GM_Triangle identified by the patch attribute of the GM_Tin that is the value of the geometry

attribute of ElevationTinCoverage. 

A.9.2 collection 

The role name collection shall identify the ElevationTinCoverage to which the ElevationTriangle 

belongs. 

A.9.3 control value 

The role name controlValue shall identify the set of ElevationPoints at the vertices of the 

ElevationTriangle. 

A.9.4 MultiElevationPoint 

The class MultiElevationPoint is described in A.6. The value of the geometry attribute of 

ElevationPoint equals one of the values of the attribute controlPoint of the GM_Tin that is the 

value of the geometry attribute of the ElevationTinCoverage to which the ElevationTriangle 

belongs. 
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A.10 ElevationContourCoverage 

Figure A.6 – ElevationContourCoverage 

A.10.1 Semantics 

The class ElevationContourCoverage is a realization of the Type CV_DiscreteCoverage specified 

in ISO 19123 that represents a set of elevation contours. It is also a subclass of 

ElevationCoverage that inherits the attributes specified for that class. 

A.10.2 element 

The role name element identifies the set of ElevationContours contained in the 

ElevationContourCoverage. 

A.11 ElevationContour 

A.11.1 Semantics 

The class ElevationContour is a realization of the Type CV_CurveValuePair specified in ISO 

19123. It has two attributes. 
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A.11.2 geometry 

The attribute geometry shall contain the instance of GM_Curve that describes the shape of the 

contour. The position of the curve is stated with respect to a 2D coordinate reference3 system. 

A.11.3 value 

The attribute value shall contain a Record consisting of the elevation value associated with the 

curve. 

A.12 ElevationPointSet 

Figure A.7 – ElevationPointSet 

A.12.1 Semantics 

The class ElevationPointSet represents a collection pf points each related to a 3D coordinate 

reference system such that the elevation value is carried as one of the coordinates rather than as 

a distinct attribute of the point. 

A.12.2 domainExtent 

The attribute domainExtent shall specify the spatial extent of the area to which the 

ElevationPointSet applies. 

A.12.3 point 

The role name point shall identify the ElevationPoints contained in the ElevationPointSet. 
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A.12.4 metadata 

The attribute metadata shall provide a link to metadata that describes the ElevationPointSet. 

A.13 ElevationPoint 

A.13.1 Semantics 

The class ElevationPoint represents a point associated with a single elevation surface. Unlike the 

MultiElevationPoints of an ElevationPointCoverage, each ElevationPoint in an ElevationPointSet 

has only one elevation value and represents only one elevation surface type. 

A.13.2 surfaceType 

The attribute surfaceType shall identify the type of surface that is described by the ElevationPoint. 

A.13.3 geometry 

The attribute geometry shall contain an instance of GM_Point. The position of the point shall be 

described in terms of a 3D coordinate reference system. One of the coordinates shall be the 

value for the elevation. 

A.14 ElevationProfileCollection 

Figure A.8 – ElevationProfileCollection 

A.14.1 Semantics 

The class ElevationProfileCollection is an aggregation of ElevationProfiles. 
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A.14.2 domainExtent 

The attribute domainExtent shall specify the spatial extent of the area to which the 

ElevationProfileCollection applies. 

A.14.3 metadata 

The attribute metadata shall provide a link to metadata that describes the 

ElevationProfileCollection. 

A.14.4 profile 

The role name profile shall identify the set of ElevationProfiles that is contained in the 

ElevationProfileCollection. 

A.15 ElevationProfile 

A.15.1 Semantics 

The class ElevationProfile represents a curve lying on an elevation surface. It is a realization of 

the Type GM_Curve specified in ISO 19107, which is an aggregation of GM_CurveSegments. 

A.15.2 surfaceType 

The attribute surfaceType shall identify the type of surface that the elevation values describe. 

The data type CharacterString is specified in ISO/TS 19103. 

A.15.3 profileType 

The attribute profileType shall identify the kind of profile from the code list ProfileType. 

A.15.4 geometry 

The attribute geometry shall contain an instance of GM_Curve. Positions of the control points for 

that curve shall be described in terms of a 3D coordinate reference system. One of the 

coordinates shall be a value for elevation. 
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A.16 DirectPosition 

Figure A.9 – DirectPosition 

A.16.1 Semantics 

The data type DirectPosition, specified in ISO 19107, is used to provide position information for 

all elevation values in an ElevationCollection. 

A.16.2 coordinate 

The attribute coordinate shall contain the coordinates that identify the spatial position of a point. 

A.16.3 dimension 

The attribute dimension is derived from the dimension of the coordinate reference system and 

specifies the number of ordinates included in each coordinate value. 
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A.16.4 coordinateReferenceSystem 

The role name coordinateReferenceSystem shall identify the SC_CRS to which the position is 

referred. SC_CRS is specified in ISO 19111 as an abstract class. The appropriate subclass from 

ISO 19111 shall be used to describe the coordinate reference system used with any framework 

elevation data set. 

A.17 Code lists 

Figure A.10 – Code lists 

A.17.1 CV_CommonPointRule code list 

CV_CommonPointRule is a CodeList of values for the attribute commonPointRule. 

Table A.1 – CodeList for CV_CommonPointRule 

Name Definition 

average 

low 

high 

all 

start 

end 
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A.17.2 CV_InterpolationMethod code list 

CV_InterpolationMethod is a CodeList of values for the attribute interpolationType. 

Table A.2 – CodeList for CV_InterpolationMethod 

Name Definition 

nearestNeighbor 

linear 

quadratic 

cubic 

bilinear 

biquadratic 

bicubic 

lostArea 

barycentric 

A.17.3 CV_SequenceType code list 

CV_SequenceType is a CodeList of values for the attribute type. 

Table A.3 – CodeList for CV_SequenceType 

Name Definition 

linear 

boustrophedonic 

CantorDiagonal 

spiral 

Morton 

Hilbert 
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A.17.4 ProfileType code list 

ProfileType is a CodeList of values for the attribute profileType. 

Table A.4 – Codelist for ProfileType 

Name Definition 

transect 

breakLine 

traverse 

ridgeLine 

drainageLine 
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Annex B 

(normative) 

Elevation data UML object description, 

Data dictionaries for framework elevation data 

B.1 ElevationCollection 

Table B.1 – Data dictionary for ElevationCollection 

Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

1 ElevationCollection <<Feature>> 2 extent Spatial extent of the collection M 1 EX_GeographicExtent 3 metadata Data about the ElevationCollection M 1 CharacterString 4 Role name: profileSet Set of elevation profile sets O * <<Feature>> ElevationProfileCollectio5 Role name: gridSet Set of elevation grid coverages O * <<Feature>> ElevationGridCoverage 6 Role name: contourSet Set of elevation contour coverages O * <<Feature>> ElevationContourCovera7 Role name: pointCoverage Set of elevation point coverages O * <<Feature>> ElevationPointCoverage 8 Role name: pointSet Set of elevation point sets. O * <<Feature>> ElevationPointSet 9 Role name: tin Set of elevation TIN coverages O * <<Feature>> ElevationTinCoverage 10 ElevationProfileCollection <<Feature>> 
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Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

11 ElevationGridCoverage <<Feature>> 12 ElevationContourCoverage <<Feature>> 13 ElevationPointCoverage <<Feature>> 14 ElevationPointSet <<Feature>> 15 ElevationTinCoverage <<Feature>> 

B.2 ElevationCoverage 

Table B.2 – Data dictionary for ElevationCoverage 

16 ElevationCoverage <<Abstract>> 17 domainExtent Spatial extent of the elevation 

coverage M * EX_GeographicExtent 

18 rangeType Description of the elevation values provided by the elevation coverage M 1 RecordType 19 commonPointRule 

Rule to follow in interpolating a value at a point that falls on the boundary between two domain objects 

M 1 <<CodeList>> CV_CommonPointRule 

20 metadata Data about the ElevationCoverage M 1 CharacterString 21 ElevationGridCoverage <<Feature>> 22 ElevationTinCoverage <<Feature>> 23 ElevationPointCoverage <<Feature>> 24 ElevationContourCoverage <<Feature>> 
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25 RecordType <<DataType>> 26 Role name: value M * <<DataType>> ValueType 27 Role name: record M 1 <<DataType>> Record 28 ValueType <<DataType>> 29 key M 1 CharacterString 30 dataType M 1 CharacterString 31 Record <<DataType>> 32 Role name: value M * <<DataType>> Value 33 Role name: description M 1 <<DataType>> RecordType 34 Value <<DataType>> 35 key M 1 CharacterString 36 value M 1 Number 

B.3 ElevationGridCoverage 

Table B.3 – Data dictionary for ElevationGridCoverage 

Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

37 ElevationCoverage <<Abstract>> 38 ElevationGridCoverage <<Feature>> 
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Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

39 interpolationType 

Recommended method for interpolating elevation values at positions between grid points 

M 1 

<<CodeList>> CV_InterpolationMethod bilinear 

40 Role name: data Sequence of elevation values M 1 <<Feature>> ElevationGrid 41 ElevationGrid <<Feature>> 42 dimension Dimension of the elevation grid M 1 Integer 43 axisNames Names of the axes of the elevation grid M * CharacterString 44 origin 

Coordinates, in an external coordinate system, that map to grid coordinates 0, 0 

M 1 <<DataType>> DirectPosition 

45 offsetVectors 

Vectors that specify the orientation of the grid axes and the dimensions of the grid cells in directions parallel to the axes 

M * <<Type>> Vector 

46 extent Limits of the set of grid points included in the elevation grid M 1 <<DataType>> CV_GridEnvelope 47 sequencingRule Rule for assigning values to grid points M 1 <<DataType>> CV_SequenceRule 48 startSequence Grid point associated with the first record in the values sequence M 1 <<DataType>> CV_GridCoordinate 49 values Recorded elevation values M 1 Sequence<Record> 50 Role name: evaluator O 1 <<Feature>> ElevationGridCoverage 51 CV_GridEnvelope 

Grid coordinates for the diametrically opposed corners of the elevation grid 

<<DataType>> 
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Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

52 low 

Minimal grid coordinate values of the part of the grid that contains elevation values 

M 1 <<DataType>> CV_GridCoordinate 

53 high 

Maximal grid coordinate values of the part of the grid that contains elevation values 

M 1 <<DataType>> CV_GridCoordinate 

54 CV_GridCoordinate Data type for holding the coordinates of a grid point <<DataType>> 55 coordValues 

Number of grid cell offsets from the origin of the grid parallel to each axis 

M 1 Sequence<Integer> 

56 Quadrilateral Grid:: CV_SequenceRule Description of how grid points are ordered for association to the elements of the sequence values <<DataType>> 57 type Identifier of the type of sequencing method M 1 <<CodeList>> CV_SequenceType = lin58 scanDirection 

List of signed axisNames that indicates the order in which grid points shall be mapped to position within the sequence of values 

M 1 Sequence<CharacterStr

59 Numerics::Vector <<Type>> 60 dimension M 1 Integer 61 ordinates[dimension] M 1 Number 62 DirectPosition <<DataType>> 63 coordinate Numerical description of the spatial position M 1 Sequence<Number> 64 dimension Dimension of the coordinate space M 1 Integer 65 Role name: crs Spatial reference system to which O 1 <<Abstract>> 
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Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

the positions is associated SC_CRS 

66 SC_CRS <<Abstract>> 67 Role name: directPosition O * <<DataType>> DirectPosition 

B.4 ElevationPointCoverage 

Table B.4 – Data dictionary for ElevationPointCoverage 

Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

68 ElevationCollection <<Feature>> 69 ElevationCoverage <<Abstract>> 70 ElevationPointCoverage <<Feature>> 71 Role name: element Point included in the coverage M * <<Feature>> MultiElevationPoint 72 MultiElevationPoint <<Feature>> 73 geometry Geometric description of the elevation point M 1 <<Type>> GM_Point 74 value Elevation at the point M 1 Record 
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B.5 ElevationTinCoverage 

Table B.5 – Data dictionary for ElevationTinCoverage 

Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

75 ElevationCollection <<Feature>> 76 ElevationCoverage <<Abstract>> 77 ElevationTinCoverage <<Feature>> 78 interpolationType 

Recommended method for interpolating values at points within triangles 

M 1 <<CodeList>> CV_InterpolationMethod 

79 geometry M 1 <<Type>> GM_Tin 80 Role name: element M * <<Feature>> ElevationTriangle 81 ElevationTriangle <<Feature>> 82 geometry Geometric description of the elevation triangle M 1 <<Type>> GM_Triangle 83 Role name: collection M 1 <<Feature>> ElevationTinCoverage 84 Role name: controlValue Elevation point at one of the vertices of the elevation triangle M 3 <<Feature>> MultiElevationPoint 85 MultiElevationPoint <<Feature>> 86 geometry Geometric description of the elevation point M 1 <<Type>> GM_Point 87 value Set of elevations at the point M 1 Record 
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Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

88 Role name: extension O * <<Feature>> ElevationTriangle 

B.6 ElevationContourCoverage 

Table B.6 – Data dictionary for ElevationContourCoverage 

Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

89 ElevationCollection <<Feature>> 90 ElevationCoverage <<Abstract>> 91 ElevationContourCoverage <<Feature>> 92 Role name: element Contour included in the coverage M * <<Feature>> ElevationContour 93 ElevationContour <<Feature>> 94 geometry Geometric description of the contour M 1 <<Type>> GM_Curve 95 value Elevation value associated with the contour M 1 Number 96 Role name: collection M 1 <<Feature>> ElevationContourCovera
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B.7 ElevationPointSet 

Table B.7 – Data dictionary for ElevationPointSet 

Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

97 ElevationCollection <<Feature>> 98 ElevationPointSet <<Feature>> 99 domainExtent Spatial extent of the elevation point set O * EX_GeographicExtent 100 metadata Data about the ElevationPointSet M 1 CharacterString 101 Role name: point ElevationPoint contained in the ElevationPointSet M * <<Feature>> ElevationPoint 102 ElevationPoint <<Feature>> 103 surfaceType Type of surface with which the ElevationPoint is associated M 1 CharacterString 104 geometry Geometric representation of the ElevationPoint M 1 <<Type>> GM_Point 105 Role name: set O * <<Feature>> ElevationPointSet 
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B.8 ElevationProfileCollection 

Table B.8 – Data dictionary for ElevationProfileCollection 

Line Name/Role Name Definition Obligation/ Condition Maximum Occurrence Data Type 

106 ElevationCollection <<Feature>> 107 ElevationProfileCollection <<Feature>> 108 domainExtent Extent of the elevation profile collection M 1 EX_GeographicalExtent 109 metadata Data about the ElevationProfileCollection M 1 CharacterString 110 Role name: profile Profile included in the collection M * <<Feature>> ElevationProfile 111 ElevationProfile <<Feature>> 112 surfaceType Type of surface with which the elevation profile is associated M 1 CharacterString 113 profileType Code identifying a description of what the profile represents M 1 ProfileType 114 geometry Geometric description of the profile M 1 <<Type>> GM_Curve 115 Role name: collection O * <<Feature>> ElevationProfileCollectio
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Annex C (informative): Bibliography

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Annex C 

(informative) 

Bibliography 

ANSI and ISO standards may be purchased through the ANSI eStandards Store at 

http://webstore.ansi.org/ansidocstore/default.asp, accessed October 2006. 

American Society for Photogrammetry and Remote Sensing, 2001, Digital elevation model 

technologies and applications: The DEM users manual 

National digital elevation guidelines, Version 1.0, 2004 

OGC 03-065r6, Abstract specification for coverage type and its subtypes Open Geospatial 

Consortium, Version 1.0.0, Open GIS Consortium, Inc.