TM 5-850-1
CHAPTER 4
SITE INVESTIGATION
4-1. Background data.
engineering terms (USCS) required for site
investigations (figure 4-1).
(3) Geologic maps. Geologic maps depict a
a. Introduction.
The principal background
number of geologic or geologic-related conditions, such
intelligence data required to evaluate the suitability of an
as the surface and substrate distribution of formations,
area for a military port are as follows: (1) Physical and
structure, and the distribution of landforms. Such maps
cultural aspects of the shoreline and contiguous interior.
often provide information regarding the configurations
(2) Weather
regimes,
intensities,
and
and dimensions of shoreline landforms, engineering
extremes.
characteristics of overburden materials, the nature of
(3) Bathymetric and subbottom characteristics.
surficial soils, and classification and distribution of
The types of data from which this intelligence data may
surface or near-surface rock and associated soils. In
be derived can be categorized as maps, photography
addition, the maps usually symbolize drainage patterns,
and imagery, documents and records, and historical
land use, and vegetative patterns.
data.
b. Maps.
Geologic maps, when prepared in sufficient detail, can
(1) Topographic maps. Scales of these maps
provide a general basis for the selection of construction
sites as well as sources of suitable construction
vary widely. Coverages of 1:50,000 and 1:250,000 are
materials.
available for sizable portions of the world, although
(4) Pictomaps. Pictomaps are usually large-
more extensively for highly developed areas. Slope,
scale maps, viz. 1:25,000, which have been prepared
relief, and configurations of shoreline landscapes are
from controlled aerial photomosiacs.
Colors and
obtainable directly from the maps, with the degree of
symbols are used to denote vegetation, hydrologic and
accuracy being a function of the scale and contour
cultural patterns, which are superimposed upon the
interval.
Drainage patterns, land use, natural
photographic image. Surface and bathymetric contours
vegetation, and cultivation are also portrayed on these
are included on the maps most frequently at 1-, 5-, and
maps, as well as population centers and transportation
10-metre intervals. The pictomap probably represents
networks. Bathymetric contours and navigation hazards
the most suitable base for generation of a three-
(e.g., mud, shoals, cock, coral, and other natural
dimensional terrain model of a port area.
characteristics) are delineated.
(5) Hydrographic charts. These charts depict
(2) Soil maps. These maps are prepared for a
hydrologic conditions along and immediately inland of
variety of purposes, e.g., agricultural potential, land use,
the shorelines of the world. Depth soundings in feet are
and construction. Soil surveys have been conducted for
presented for both offshore and inland waters.
entire countries in some instances but more frequently
Navigable waterways are indicated, and navigation
cover only limited areas. The distribution of soils is
hazards and man-made structures, such as platforms,
portrayed on soil maps, and the descriptions are
stakes and markers, and lighthouses are located. Tidal
normally in textural terms. Soil depths data are
information is provided for selected stations on the
available for portions of West Germany, while
chart.
1:1,000,000 maps represent the best coverage for
(6) Climatic maps.
These maps may be
certain poorly developed countries. World soil maps,
compiled for individual countries; however, they are
excluding the United States, have been prepared by the
most often compiled for the entire world and thus are
United States Soil Conservation Service (USCS) with
usually small scale. They portray the distribution of
the descriptions in United States Department of
areas characterized by ranges of mean annual
Agriculture terms. The distribution of soils portrayed on
temperatures, precipitation, and climatic types
these maps is usually determined by landform and
determined by combinations of temperature ranges;
physiographic association and is of questionable
amount and frequency of precipitation, and natural
accuracy. Detailed soils maps prepared in support of
vegetation. Other climatic maps depict the distribution
agricultural and engineering studies provide
of major ocean currents, mean sea surface
comparative detail, but their occurrence is sporadic and
temperatures, hurricane tracks, air masses, and other
unpredictable. In many cases, the descriptive
relevant characteristics.
agricultural terms used in soil surveys are translatable
c. Photography and remote imagery. Photography
into the
4-1
Previous Page
