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SYMPOSIUM PHOTO INTERPRETATION, DELFT 1962 
The remote and often inaccessible nature of much of the Arctic results in very 
high costs for obtaining engineering information by conventional ground 
survey procedures. Many areas of the Arctic have only recently become ac 
cessible and information available in the literature, which is directly applicable 
to particular engineering problems related to soils and permafrost, is virtually 
nonexistent. This paper presents a generalized technique for obtaining infor 
mation of this nature by organizing important aspects of the terrain as reflected 
on airphotos. 
Concept of Terrain Organization 
Obtaining engineering information from airphotos about the physical prop 
erties of the terrain is contingent on: 1. knowledge of the formation of terrain 
features (origin and erosional history) and the environmental stresses active 
in an area; and 2. how various indicators of the above express themselves on 
an aerial image. The most successful method employs a logical classification of 
the landscape or stated in other words developing a “Terrain Organization 
Concept”. 
Background information can be obtained by following the guidance of such 
classical works as Lobeck’s “Geomorphology” in initiating a classification 
scheme. For example, Lobeck considers three landform categories based on 
order of magnitude, such as: first order - the continents and ocean basins; 
second order - the physiographic forms (largely constructional) comprising 
the continents; and third order - the minor or local landforms (largely de- 
structional). When using this as a basis it must be remembered that landform 
names refer to recurring terrain units and denote origin, structure, composition 
and space relationships. In utilizing the landform approach to terrain organiza- 
Fig. 1. Photograph of a young stream 
flanked by alluvial terraces on the shallow 
lower slopes of a dissected granitic upland 
Fig. 2. Mental picture of the photograph 
(Fig. 1) can be compared to this block dia 
gram showing structure and composition 
of the landforms and their location with 
relation to the other landforms