ERTS-1 imaged the western portion of Nicaragua on December 24, 1972, one day after the central part of the city of Managua was devastated by a major earthquake which measured 5.6 on the Richter scale. ERTS-1 images reveal sets of lineaments (which may reflect fault systems) along any one of which movement could have taken place. One set includes a line of active volcanoes that parallels the coast and constitutes the southwestern edge of the Nicaraguan Depression, a regional graben which cuts obliquely across the Central American isthmus. This trend is offset approximately 10km in a right lateral geometric sense just west of the city of Managua. A parallel lineament, north of Lake Managua, marks the northeast edge of the graben. A second set, extends northward to northwestward from the mouth of the Rio Grande (Viejo) north of Lake Managua and can be projected southward across the lake to Managua. It is this set along which geometric offset of the volcanic lineament appears to have taken place

Carter, W. D.

Eaton, G. P.

English

NASA Technical Reports Server

Paper G 24 
ERTS-1 IMAGE CONTRIBUTES TO UNDERSTAND1 NG OF GEOLOGIC 
STRUCTURES RttATED TO MANAGUA EARTHQUAKE, 1972 
W. D. Carter and G. P. Eaton, U. S, Geologicel Survey, Weshington, D. C. 20244 
ABSTRACT 
ERTS-I imaged the western portion of h'icerap,ua on December 2 b ,  
1972, one day after the central part of the c i t y  e f  ?!anagua was 
devastated by a major earthquake which meaaured 5.6 ~m the Richter 
scale. ERTS-1 irna~ea reveal four sete of lineaments (which may 
reflect famult ~ y ~ t e m e )  along any one of which movement could have 
taken place. One s e t ,  trending N 50' W, includes a l i n e  of 
active val~enoee t h a t  parallels the coaat and con~titutea the 
souchweetern edge sf the Nicara~uan Depression, a regional graben 
which cuts obliquely across the Central hmesican iatbrnus, This 
trend i a  offset approximately POkm i n  a s ight  lateral geometric 
sense just  west of the c i t y  af Yanagua. A paral le l  lineament, 
north of Lake Yanagua, marks the northeast edge of the graben. 
A second set ,  trending due N-S to N 25"  k', extends northward to 
northwestward from the mouth of the Rio Grande (Viejo) n o r t h  of 
Lake ?lana~ua and can be projected southward across the lake KO 
Uanagua. It i a  thiu set  along which geometric offset of the 
volcanic lineament appears t o  have taken place .  Tt i s  paralleled 
by a belt of young p i t  craters at  the west  edge of the city. A 
t h i r d  set  of l insars  trends approximately Y 50'-60' E across the 
Picaragu~n ttench. The fourth set ,  wh!ch is less cansplcuous, 
i s  represented by only three identified members d t h i n  Nicaragua. 
Two others, which are subparallel, are visible on the image i n  
the area of Honduras, to the northwest. This set  i a  notable f o r  
the fac t  that it extends from the  coast entirely acraes the Nica- 
raquan Depressf on. Tta trend is N 25"-45" E. Aerial photographs 
and f i e l d  atudies  i n  t h e  c i t y  of Vanawe by other U. S. Geolo~ iea l  
Survey pereonriel (Rrawn, k'ard, end Plafker, i n  prese) indicate 
t h a t  this fourth eet  is represented by four currently active, l e f t -  
la tera l ,  etrike-sl ip faults  and a ilarrov belt  of aftershock 
e p i c e n t e r s ,  Instrumental data indicate that the efterahock earth- 
quake foci are of shallow depth (c10.0 kilometers). 
Publication authorized by Director, U, S. Geolopical Survey. 
459 phct'eraphy my be purchased t -,: :. . i": 
~ ~ E " I ~ G  PAGE BLAm NOT FILMB) Ib. .;.! Da)JbiJj Avenue Sioux Falls, SD a7198 
https://ntrs.nasa.gov/search.jsp?R=19730019523 2020-03-17T08:43:36+00:00Z
Managua, Nicara~ua,  uaa devastated hv a series of 3 Iarge rnrth- 
quakes on December 23, 1972, the principal s h ~ c k  havinp a rnapnituir 
af 5.6 en t h e  R i c h t e r  scale. The loss of  l i f e  has  been estimated 
to exzeed 11,000 persons and t h e  damaa~ ta prnpettr vaLued at 
hal f  a b i f  Zion dol lars  (Ifso~.n, Idlard and Plafker,  1933). Such 
destruction, a6 with the 1931 and 1?hR earthquake::, was determln~d 
to he the result nf two related causes: (11 The c i t y  of Yana~ua 
is located on ponrlv consolidated sedlments (scor l a  and as111 af  
volcanic oriain; and ( 2 )  Xanv of the bui ld fnps  are can~tructed nf 
materials (masonry and tarquezal) that have little resistance to 
strong shaking. wirecr  displacement of structures situated ~lnnp, 
the course of active f a u l t s  acrouneed for severe damage t o  
buildings wlth better quake resistance (Rrown and others, op. cft,). 
On December 24 ,  1972,  the Earth Resources Technolo~y Sate l l i te  
(ERTS-11, in orbit approximately 900 kilometers above the ear t!t, 
acquired two multispectral irnaaes !~ :ASA ERTS-1151-15385 and 
15391) over Managua and sdjarent areas t o  t h e  west .  These images 
were p~ocessed  by NASA's Godderd Space F l i g h t  renter and forwarded 
to U. S. Geclo~ ica l  Survey scientists far interpretat f o n ,  ?Iuch 
of Xanauua was under scattere8 cloud cover, and therefore none of 
~ l ~ e  dama~e  could bc defined. The area in the rest of the scene was 
cloud free, however; thus, i t  was possible to alap a nlimher of 
geologic features that may bear some re lat ion t o  regional earthquake 
condi t ions  and which cantriSute t o  ~ e n e r a l  knowledge of the region, 
The purpose of this preliminary report i s  t a  debcribr the evaluatian 
of the  ERTS-1 imagery and t h e  results af  rapid data interpretation 
(appraxfmately 3 hours). 
2 ,  MFTHOD OF APPROACH 
The authors have not visited rlicaragua a& had access t o  only a 
very l i m i t e d  selection of library material when the interpretation 
was carried out in mld-January 1973. Positive 9" x 9" transparencies 
placed on a light table  and an 8x magnifier were used t o  mak? mylar 
overlays. Diazo-foil,  falee color  composites were made using a 
startdard t)zalid printer. 
The ERTS-1 imagia~  system is a 4-band multispectral scanner (ass) 
in which the green (0.4-O.Sum), red (0.5-0,6um), and two infrared 
bands (0.6-0.7um and 0.8-1.lprn) can a l l  be used t o  ident i fy  features. 
The ioliouing paragraphs attempt t o  explain their differences and 
contributions. 
The green hand (MSS-4) was somewhat affected hv haze hut clearlv 
show3 either sediment distribution or near-shore bottom features 
of xater bodies a; both (Figure I ) .  For example, twa crater lakes  
on the Chiltepe peninsula of Lake Managua can be seen, b u t  their  
tones are different. The l i ~ h t c r  one i s  apparently mare turbid 
than t h e  darker. Marshland areas appear in tones lighter tharl 
water but darker than the surrounding 1 ~ 1 i d  areas. Volcanic ash 
and laves comprising volcanic cones arid surrounding debris f i e l d s  
are darker ~ h a n  adjacent materials. Vepetat ive  areas such as  
farmlands and cultural  f i e l d s  are d i f f i c u l t  t o  define. 
The red band is clearer tc overall appearance because haze has 
leas e f fec t  in this region nf t h e  spectrum (Fimre 2 ) .  The land 
surface tones are dark shades of gray due to the Fseaence of 
vegetation. Cultural and soil Features are c learly  displayed. 
Water penetration is  minimal, but sediment plumes in estuaries 
are clearly visible, 
The two infrared hands are very similar in t h a t  edges of warer 
bodies are sharply de f  Lned in black [Figure 3) . ?larshland and 
levees can be clearly delineated in these bands, znd they a te  also 
excel len?for d e t e r m i n i n ~  the presence of Water in Small rivers,  
strcams, and arroyos, 
Surface tones of land areas are b r i ~ h t e r  i n  the inisared bands 
than i n  the green and red bands due to higher reflectance of vege- 
tatian which appear i n  shades o f  white t o  light gray [Plgures 3 
and 4 ) .  Cultivat ; croplands are brightest (exelusive o f  clouds 
and snow) and can easi ly  be defined. Natural vegetatior. appears 
as l i g h t  gray. These bands axe most uaefvl in defining tectonic 
f eat-~res,  such as volcanoes and lineametrts. Cultural features, 
such as small towns and cities, stand out ag dark patches somewhat 
similar in tone t o  volcanic cfnder cones. Their rentangular t o  
irregular box-like patterns, caused by road grfds  and lack of 
radial drainage, enables one t o  dfstinguish them unambiguously. 
Soil tonea are subt le  shaaes of Rray and therefore &re difficult 
to d i s t i n ~ i s h  frm natural vegetation 19 the black and white 
rendit ions of the scene. They are, however, easily distinguished 
io polor combined renditions (Figure 5 ) .  One great advantage of 
these bands l e  the fact that one can separate natural vegetstion 
from shadowing produced by the angie of solar illumination; in the 
red and green bands, bowever, this is more d i f f i c u l t .  
Because of the earthquake-related destruction of  Managua, a 
preliminary g e c l o ~ i c  structure map was made t o  see if such informa- 
t ion  w u l d  a s s i a t  ground studies concerned with the damage. The 
map (Figure 6 )  showa the result of about three hours of interpreta- 
tion. These s tudies  are continuinp and more information is being 
extrac'=d. Figure 7 was prepared In about 10 hours hv Dr. J. N. Rlnker. 
The mast obvious tectonic features v i s i b l e  i n  the scene are t h e  
Holocene volcar-oes alfgned parallel to the coast. This linear 
arrangement trends S 50° E d i r e c t l y  toward the  city ef Managua. 
Many of the volcanoes are recognized by t h e i r  dark tones and 
circular patterns. Many show drainage scars r a d i a t i n ~  from their 
central cane and Lobate forms or Berate edges a t  the termini of  
thefr flous at  the margin of t he  volcanic d e b l i s ,  Several are 
marked by crater lakes which are seen aa black spots i n  the near- 
fncrared bands. Two that  are clearly v i a i b l a  pre Laeuns de 
hpoyeque end Laguna de J i l o a  on Punta Chiltepe,  a peninsula on the 
southwest chore of take Managua vithin 10 kilometers of the ci.: 
Three other crater lakes, under c l o ~ d s  in  the scene, lie juec 
south of the city. One o f  these at  the edge sI the  c i t y ,  La~una 
de Tiscapa, i a  a residential area which includes the Presidential 
Palace and the U. S. Embassy, an area where considerable damage 
to structures aas reported. 
Of next importance Is a narrow be l t  of Ifnear features that trer,,s 
north t o  north-northwest (due N to ?I 25" W) on the nor% h i d e  of 
Zake Managua. A projeerion of t h e s e  linear8 to the south, across 
the lake, i n t e r a ~ c r s  t h e  volcano linear northveet of the c i t y  of 
Managua. The volcanic linear is  offset approximately 10h, with 
the east block apparently di~placed  t o  the soueh, This displacement 
is not visible or the image, but ie seen i n  the regional geologic 
map (Figure 8). 
A third and fourth s e t  of prominent lineare strike north- 
northeeatward and norrheaatward (N 25'-45' E and N SOQ-60' E) , 
reapecttvely, ercneing both the volcani.: trend and the Nicaraguan 
Depression, Although it can not be sees i n  the ERTS-1 scene a t  
hr,agua beeau~e  of cloud cover, Hr. Leroy Aneteud of LAGS, on duty 
i n  Managua a t  the t+me af the w e n t ,  reported north-northeant 
trending eartheracks in the c i ty .  They were v i ~ i b l e  on the ground 
and in  l o r a l t i t u d e  (ecale 1: 5,000) aerial photography. Thie eet 
has been mapped in d e t a f l  by Brown, Ward, and P L i k e r  119731, and 
it i s  paralleled by a narrow band of earthquake af texehocka. 
Strike-slip offset &,f a €ev t o  aweral tene of 
cent?metera wae meemred in walls, aidewalk cufb8, and roade that 
interaeeted these fractusee, Thia trend had been mapped earlier 
both by Juan Kuan 5 .  and Carloa V a l h  G. (writtel,  coumnication, 
undated) and on s radar mosric of the cwatrp by Anrtead (oral. 
ccrmmunicatim, 1973) and athers f o r  a length of wer 100b. Zm8much 
as this met is paralleled by three athex llncrmmts seen on the 
ERTS image t o  the northweat, regioml f feld invemtigatioae of thin 
s e t  would meem to  be dtsirable f x m  the standpof.nt of asseasing 
regional e a r t h q u k c   hazard^. 
The euthors had the opportunity to h r i e f l v  s t c d p  color Infrared 
photojiraphv acquired fro;! t h e  XbSA C-133 air--aft on or about 
December 28, 1972. The frame w h i c n  covered tile center 
of the cfty revealed the area of Rreatest damage to  be white to 
l i g h t  gray in tone, crudely e l l ip t i c s l  i: ~ h a p e  and covering abo-lt 
70 blocks in area. The damage zone, trending east-west, is marked 
by eollapscd roofs, walls, and extensive rubble fn the s:reets. 
An extension of damape was seen in smal l  areas t a  the  north-  
northwest. rxtena e damage a l so  extended along this line, south 
o f  the probable epicenter of +he maic shack, to  a small crater 
lake (Laguna d t  Tiscapa; next t o  w h i c h  were the Presidcritial 
Palace and the U, S. h b a s b y .  These were reported to be damaged 
beyond reps i r .  
The Manawe earthquake of Decenrber 1972 i:;:nstitu.:ed en early test 
of the s b i l ~ t y  of the ERTS-I byatem to  res?ond I.o a disaster 
situation. The alestneas of the NASA aatelllte mnnagement team 
enabled the acqutsition of data on the day following the event. 
b p l d  sage processing by the CoJdard crew put data in the hands 
of geologists within 5 days of the event and copies  o f  the i n l t i a l  
Interpretation were placed in the hands of t1,c Nicaraguan Bnbassy 
~ i r h i n  2 t.--.mqrs. The data obtained provided good hackground 
inCormarion on the suriaee geelogy and structure of the region. 
Althou~h cloud cover and smoke prohibited deta i led  s tud ie s  of 
destruction withfn the c i t y  of Managua from ERTS-1, the dectr3yed 
area w&?i large enough t o  have been detected in enlargements of 
ERTS-1 data at scales of 1:250,000 or lr100,OOO or in computer 
proemeLnng of the tapes. Repetitive data taken 18 days after the 
event wcm:ld hatre been ~rsefuL f o r  cumparat:ve purpoeeq. Pre- 
earthquake ERTS-1 im~gery of Managua would also be extremely valuable 
in a ~ s e s e f n &  changes associated with the earthquake. 
4 .  REFERENCES 
Brown, R. D,, Jr., Ward, P. L., and Plafker, George, in preae, 
:eologie and seismologic asp€ ets  of the Hanagua, Nicaragua, 
sestbquakes of December 23, 1472: U. S* Geol. Survey Prof. 
Paper 838. 
Figure I. - Zaagt of Wiearagun, Eland 4 shmiag 
sediment plume in Bag of Ponseca 
Figure 2, - ERTS-1 Image of Wie8ragun, Bad 5 
ehowing culturnl ftaturca 
Figure 3. - ERTS-1 Image of Nicaragua, Band 6 ahov-lng 
distribution of volcanic centere eqd vater 
hcd:es 
P i p r e  4. - ERTS-I Tmsge of Nicsragun, Band 7 shoving features 
deecribe.3 in Figure 3 but f-m which interpretation 
uaa made 
DEPARTMENT OF THE INTERIOR 
UNITED STATES GEOLOGICAL SURVEY 
.d * I.. , .'.' .,' . .'.I 
.r' ,*#., 
* . . \ : L L L & i " . . / < ' ,  h, \ * 7 c ; * . ' & ~  -+ . ' , ,  - - - . '+c - 6 -  - I , - .  - - .  . ... 
, ,Y.C.  
.Y ..4- 
Imw by ~ l p n o l  A w r o r m ~  d FALSE COLOR COMPOSm IH .AM 
S p - *  Adminisboth, 1072 
Figure 5 Falac color composite W g e  of Unda 4, 5, f 

N A S A  EARTH RESOURCES TECHNQLOGY SAT€t.LITE (ER*S-; ) I M P C ~  
NORTHWEST OF "MANAGUA, NICARAGUA-lhhGE AND FRACTURF PkTTFRNS, l Q7 i 
. . 
- . >  
w.n." w- 
IMAGE SHOWfNG FRACTURE PATTERN ANALYYS 
By J. N. Rirrker Defmst Mopping t gency 
Figure 7 
Image showing more detailed fracture pattern snalyafa by 
.I. 9.  Rinktr, DU4 
Figure 8 
The Wnagua Earthquake e m r y  showing preliminary reimolagic 
and ~eologic inveetigation sourcee and p r d u c t n  
47 1 


ERTS-1 image contributes to understanding of geologic structures related to Managua earthquake, 1972

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server