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THE DEFINED SYSTEM OF MAP SYMBOL BASED GEOLOGICAL SUBSTANCES 
Xincheng Guo a ,Yongqing Long b ,Weiyong Ji a 
a School of Geology and Survey Engineering, Chang’ an University, Xi’an, Shanxi ,710054 -jwyl027@126.com 
department of Urban and Resource Sciences, Northwest University, Xi’an, Shanxi ,710069 
Commission VI, WG IV/3 
KEYWORDS: Geometry, Mapping, System, Standards, Correlation 
ABSTRACT: 
At present the defined symbol of filling block, linear, surface based point, line and surface is a common visual method of Map 
Drawing Computer Software and Geographic information. In fact, the direct expression map symbol is insufficient a half of 
common schema , so effective producing map symbol is one of the most important problem drawn by geographical information 
technology platform. After analyzed medium scale map symbol, the attribute of map symbol and spatial object, relations among 
geometric object, the author studied the law of map symbol composite, random and directivity , summarized and proposed the 
defined system of map symbol based geological substances. The features of the system are corrections of symbol and the attribute of 
geological substances, corrections of symbol and geometric types and features of geological substances. 
The points of the system are as follows. 
1. symbol depending on geometric types: point, line, surface, noodle; 
2. redefine of geometric object: the new geometric object constructed by geometric object is used to produce complex symbol. 
3. the concept system of symbolic definition: proposing the concepts of single meta symbol, basic symbol, graphic element symbol 
and so on. 
The paper showed all the symbol of 1:500-1:2000,1:5000-1:10000 schema constructed by the system, and reflected that the system 
was effective. 
1. FOREWORD 
A map symbol is a main way of space information 
Visualization» And the map symbol is a method that can express 
the regional map characteristic « At present, the map 
Visualization of Space DLG data basically adopts the style of 
point, line and Region. Point mode represents Point symbol, 
line type represents line symbol, and filled region represents 
region symbol. In the DLG map, symbol is unable to keep 
compatibility with the map. And extensity and symbol can’t get 
compatibility too. 
For the sake of overcoming all above problem, we bring 
forward the Object Oriented Geographic spatial Model, as 
shown in Figure 1. 
Figure 1 the Object Oriented Geographic spatial Model 
On the basis of the above model, Geographical entity can be in 
the form of attribute, geometric object and symbol. Moreover, 
geometric object of different geographic objects can be identical. 
We can such understand, the symbol and geometric object are 
independent, and the entity has not only the feature of geometric 
object and symbol, but also its own feature and attribute, and it 
can be as an independent object and derive a new object. 
Different objects can be not only independent but also 
dependent, and also can mutually inherit the feature and 
attribute of others. This peculiar request need that the map 
symbol own more powerful adaptability, but the symbol system 
on the basis of point , line , region-based symbol system is 
being a lot of defects, for example, such indicating problems of 
the symbol and geometric characteristic in the condition that the 
location of different geographical objects are the same. 
At present the map symbol’s characteristics are as follows: 1) 
the symbol on the basis of point mode , line type and filled 
region is unable to be qualified for expressing the complicated 
map symbol; 2)Symbolization of geographic information can 
not be subject to attribute and geometric object.3) the robotized 
degree of the map symbol is not high .4) the basic attribute of 
geographical factors is unable to be automatically indicated, and 
so on. 
For all the above, we bring forward the definition system on the 
basis of the spatial characteristic of map. 
2. MAP SYSTEM ANALYZING 
2.1 Map Symbol’s Orientation and Non-orientation 
Characteristic 
As the main way that expressing the map, the map symbols 
should not only confirm the position of the geographical objects, 
but also highlight the character of the geographical entity, so 
which determine its orientation and non-orientation 
characteristic. As cliffy slope symbol, as shown in Figure 2, the 
generatrix shows the position of cliffy slope, and the burr show