1 - NGA

I
*tbn, Oarabliahsd to increasethe rrurrtrerof
oontrol stations in a givan area, or to placa a
~afbn in a desired boofbn Mare If k
U1’PMCtMe u un~ to @abtiah a
princ@l StaIbn. s~kmentsry Stsibna are
perrnenerSiy marked, and are earabliihad with
an accumwy and Pm&ion somewhat bwer than
is required for a principal statii, sirwa they do
not serve as bases from whiih rmtensive
surveys are nm. Also called secondary
station.
●urfaco ●nomalloa—lrregularhias at the
Earttr’e surface, in the weathering zone, er in
near surface beds wfrbh interfere with
geophyaicsl maasuremants.
surfaco chart-See weather map.
surface corractlOns-Corrections of
geophysical measurements for surface
enomefies ard ground elevations.
surface float—A device, spacialfy designed or
improved, used in hydrogrephic surveys to
determins surfece movement of e sfmsm.
surface-A level of spstiel massumment Y . .
referring to a thrsa~lmenzionsl defirmd space,
e.g. contours, izolirras, bsthymatry, etc.
aurprlnt—See overprint, defin~lon 1.
eurvey coordirretes-See recteng ul.rrr
space coordlrmtea.
survey nat—1. (horizontal control) Arcs of
triangufat”bn, sowrefimes with lines of traverse,
connected 10 form a system of beps or circuits
exietilng over an area. Also callsd horizontal
control survey net: travereo ne~
triangulation net. See alse trlmngul=tlon
system: trilnteretlon not. 2. (vertical
cmnlro~ Lines of spirit Iavefing ccmnacfad to form
a system of *s or circuits extending over an
area. Also called control not; framework of
control; level ne~ nat. See 6[s0 ●r.a
trlengrrlation; U.S. control aurvoy nets.
●urvoy photography—See mepping
photography.
survey ●lgnal-A natural or arfifmiaf object or
sfrrm!ure whose hori.zontef and aomafimes
verf’kal position is cbtairred by surveying
methods. Signals ara given special designations
accerding to the kind of survey in wfrich Ihay em
determined, or which they -y tater aawa.
MIL-HDBK-B50
248
●urmy t,oww-A ekuctura dwaii tor rapid
mmdmdon and removal to raise the survey
instrumerS and observer ekova tiruct”m
such as trees end buildings to permit a lme-ofsight
as required in higher order triangulation,
triletsration, or treversa. See also Bllby steel
towor.
survaylng eccaeeorlae-Thoee suweying
devices wtich assist in making measurements
with e aurveyirrg instrument.
●unreylng dtlmater~n aneroid bammater
with a dief gmduated to read feat or matars of
affiiude, used to determine approximate
diiarancas in alevat”kmrbafwean points.
surveying cemer~ee mapping
camera.
aurvoylng lnatrumanta—Those surveying
devices with vhich masaurements are made.
See also electronic dlatancrr-maasuring
equipment: Iavellng Instrument:
tachometer: theodollte; tranalt.
aunreykrg aeztnnt-A sextant intended
primerity for use in hydmgrsphii surveying. Also
called hyrfrographlc eestent. See alse
marina sextent.
Surveyor”a errow—Ses pin.
$uWOYOr’a chalrr-See Gunter’a cheln.
survey-l. The act or oparetien d making
measurement for determining the relative
positions of points on, above. or beneath the
Eanh’s surtaca. 2, The re.sulta of such
opomtions. 3. An organ.uation for making
eurveya. Sea also eerlal ●urvoy; Airborne
Control system; alrborno .Iectronlc
survey control; ●rea survey; metronomic
surveying; boundary ●urvey; ced-etral
eurvey; city eurvey; compeee ●unrey;
control ●urvey; controt ●urvey
clenalflcatlon; dependent reeunroy;
electronic survey; ●nglnmerlng survey;
exploreto~ survey; field InspectIon;
flrat-order work; gaodatlc survay;
gaoalactric survey; gaographlc ●urvoy;
geologic aurvay; gravimetrlc ●urvay;
ground aurvay; hydrographlc ●uwey;
lndependant roeurvey; Inventory ●urvoy;
land survey: location survey: magnatlo
●urvey: magnetometer survey: meteeand-bounds
survay; mlna aurvay;