terrain photography on the gemini iv mission - preliminary report

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N A S A T E C H N I C A L N O T E

TERRAIN PHOTOGRAPHY ONTHE GEMINI IV MISSION:

PRELIMINARY REPORT

by Pan2 4). Lowmun, Jr., Jumes A. McDiuitt, und Edward H . White I t Goddard Space Flight Center Greenbelt, M d . ,*~.i . . *'

N A T I O N A L A E R O N A U T I C S A N D S PA CE A D M I N I S T R A T I O N W A S H I N G T O N , D . C . J U N E 1967



TECH LIBRARY KAFB, NMI11111111ll1 lllll11111111lllll11111111111111OL3LOZ5

NASA TN D-3982

TERRAIN PHOTOGRAPHY ON THE GEMINI IV MISSION:

P R E LIMINARY RE PORT

By Pau l D. Lowman, Jr. , Ja me s A. McDivit t ,

and Edward H. White I1

Goddard Space Flight Ce nte r

Greenbelt , Md.

NATIO NAL AERONAUT IC s AND SPACE ADMlNISTRATION

For sa le b y the Clearinghouse for Federal Scientific and Technical Information

Springfield, Virginia 22151 - CFSTl price $3.00



ABSTRACT

During the 4-day Gemini IV flight in June 1965, about

100 color pic ture s of land a re as were taken with a 70"

hand-held camera for geologic and geographic study, as

part of the Synoptic Te rr ai n Photography Experiment. This

paper presents a brief sum mary of the objectives, methods

and results of the experiment. Representative pic ture s of

the southwestern United States, northern Mexico, and por

tion s of Africa and th e Arabian peninsu la a r e presen ted and

described. Prelimina ry study indicates that these pictures

will be useful in studying regional stru ctur e, revising s mall-

scale geologic maps and searching for and studying impact

structures.

ii



CONTENTS

Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . 1 SOUTH WEST ERN U.S. AND MEXI CO . . . . . . . . . . . . 2 NORTH AFRICA . . . . . . . . . . . . . . . . . . . . . . . . . 7 ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . . . . 11 R e f e r e n c e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

iii



TERRAIN PHOTOGRAPHY ON THE GEMINI IV MISSION:PRELIMINARY REPORT

bY

Paul D. Lowman, Jr., James A. McDivitt*

and Edward H. White IIt

Goddard Space Flight Center

INTRODUCTION

During the Gemini IV flight in June 1965, color photographs of selected land a re as w ere taken

as part . of the Synoptic Ter ra in Photography (S-5) Experiment (Gill and Gerathewohl, 1965). Th is

paper presents a brief sum mary of the objectives, methods, and re su lt s of th is photography.

The purpose of the S-5 Experiment w a s to obtain smal l-scal e col or photographs of land are as

of geological and geographical inter est . Similar attem pts during Mercury flights MA-8 and MA-9

(Lowman, 1964), we re successful enough to warra nt fur the r efforts. The cam er a used in these and

in the Gemini IV flight was a hand-held modified Hasse lblad 500C with a Zeiss Planar f/2.8 lens

and haze filte r. On the Gemini IV mission, fiv e magazines , each loaded with approximately 60

frames of 70" EMachrome MS (SO-217) fi lm on a 2 mil Es ta r base , with an ASA 64 rating, were

car rie d. In addition to the S-5 Experiment, this film was used for gene ral purpose photography

and the Synoptic Weather Photography Experiment (S-6) (Nagler and Soules, 1965). Ca mera prep ara

tion, fi lm calibratio n, and film processing w ere done by the Photographic Technology La boratory of

the Manned Spacecraft Center.

Coverage was reques ted for thre e maj or ar ea s in the ter rai n photography experiment. First

priority w a s given to photography of the southwestern United St ate s because of the avai labi lity of

ground con tro l and geologic information. Second pr io ri ty w a s given to northeastern Africa and the

Arabian peninsula because of t he geologic importance of the G reat Rift Valley, a major study objec

tive of the Upper Mantle Project, Third priority w a s given to no rth ern Mexico. It was stressed in

pre-flight brief ings that good pictu res of any land area would be of value, i f the planned areas could

not be cove red.

Two techniques were used i n the te rr ai n photography. For systematic overlapping vertical

cove rage along the flight path, the command pilot (McDivitt) oriented the spacecra ft, using th e

*Lt. Col., U. S. A ir Force; Astronaut, Manned Spacecraft Center. tLt. Col., U. S. A ir Forc e; Astronaut, Manned Spacecraft Center; D e c e a s e d .



pulse mode, while the pilot (White) took pic tur es at 5-second intervals. Because of fuel and power

restrictions, th i s technique was used only once, durin g the 32nd revolution. At other ti me s the

spac ecra ft was in drifting flight, and pictu res we re taken by eith er astronaut whenever opportuni

ties arose. As far as possible, pic tures were taken at high depression angles, with cockpit lights

out, camera axis norm al to th e window, and the window in shade. A resid ue on the windows,

probably caused by flashback during second stag e ignition, had little effect on picture quality.

The experimen t wa s highly successful. A continuous se ri es of 39 overlapping, high dep res sio n

angle pict ures was taken covering northern Mexico and the southwestern United State s from the

Pacific Ocean to central Texas. Over 60 high-quality pic tur es of the othe r desi red areas were

taken. The coverage is summarize d in Table 1 . Detailed study of the terrain photographs is

underway by sev era l organizations. A full discussion would be beyond the scope of this paper;

instead, a few representative pictures will be presented and briefly described.

Resolution of the photographs ha s been studied in two ways. Examination of enlarged print s

showing cultural feat ur es of known dimens ions pe rm it s esti mati on of ground resolution. Fo r

high-contrast, linea r objects in dry ar ea s, maximum ground resolution appea rs to be between 30

and 40 feet; fo r example, Rt. 5, a two-lane black-top roa d about 35 feet wide on the east coast of

Baja California (Figu re 2) is visible for most of its length in the photograph. A second technique

fo r estima tion of reso lution is edge analysis . The Data Corporat ion, Dayton, Ohio, performe d

such an edge analy sis by scanning a coastline (Figure 10) on the original flight film with a micro

densitom eter and then deriving the modulation trans fer function fo r the resulting output (Refer

ence 19). Theresolution thus derived, for what was considered a medium contrast target, was

30 lines per millimeter.

No. ofFilmTerrain

IdentificationPictures*

Magazine 8, 54

Roll 3

Magazine 9, 23

Roll 4

Magazine 16, 17

Roll 5

Magazine 7, 10

Roll 2

Magazine 6, 10

Roll 1

Table 1

Photographic Data.

Areas Covered

Northern Mexico, southwestern

United State s, (continuous cover

age), Florida and the Bahama

Islands (intermittent coverage)

North Africa (18 pictures) Persian

Gulf, southeastern United States

Mexico (2 pictures), Arabian

peninsula and adjacent are as ,

Mauritania (1 picture)

Bahama Islands (5 pict ures) ,

Arabia n peninsula

Northeastern Africa (7 pictures),

Iraq, India, Pakistan

Comments

Continuous sequence of exceptional

quality; intermittent pictu res show

considerable offshore detail.

North African pictures generally

good; United States pic tur es poor.

Arabian pictures very good;

Mauritania picture shows Richat

structures.

Bahama pictures show underwater

topography.

N i l e River and surroundings well

covered.

'All pictures showing recognizable land areas are included in these f igures without regard to picture quality .

2



SOUTHWESTERN U.S. AND MEXICO

Figure 1, the first of the continuous series taken on Magazine 8, shows a portion of Baja

California. It dem ons trat es th e unique value of hyperaltitude photography by providing a synoptic

view of the Agua Blanca fault, the lineament at lower left. This strike-slip fault was first described

in 1960 by Allen, Silver, and Stehli (1960). Str eam alignme nts onthis and the succeeding photograph

suggest that it is one of a group of at least three northwes t-trending faults. Numero us additional

northeast-trending lineaments, possibly representing complementary shear faults, are visible

nor th of th e Agua Blan ca fault. Curiously, there is little photographic evidence of the major.fault

ea st of the Si er ra Jua rez shown by Bea l (1948) and Allen, et aL (1960), although its existence has

been confirmed by field mapping (C. R. Men, personal communication).

Figure 1--Northern Baja California, Mexico. Aqua Blanca fau lt is t h e lineament paralleli ng

the spa cecr aft window (dark) at lower left, North at top. East-West dis tance a t top of photo

graph about 80 miles.

3



This and the two succeeding photographs have been used by the Courteil on Non-renewable

Natural Resourc es in Mexico to construct a photogeologic map at a scale of 1:25Q,QOO, showing a

number of structures and lithologic contacts not previously mapped.

Figure 2, the third picture in the continuous 32nd revolution sequence, s h ~ w sth e "cu i of

the Colorado River? the north end of the Gulf of California and adjacent A a j a California and Scnior9.

Considerable geologic detail is visible, such as the lineament sub-parallel to the edgc of the SorioraDesert; this is a major fault of the Saul h d r e a s system (Moody arid Hill, 1956). Of equal interest,

however, a r e the many tonal gradations (color in the original tr ans par enc ies ) %risiblein the Gulf

of Calif ornia Gettys (1965) has shown that they represen t var iation s in water depth; asgiiiiiietrie

sediment distribution is apparent i n the picture.

Figure 2-Mouth of Colorado River, emptying into the Gulf of California. Sinuous feature

at left i s an ephemera! stream. Great Sonora Desert at right; note sand dunes.

4



Figure 3, the fifth picture in the sequence, shows S ie rr a de l Pinacate and adjacent Sonora and

Arizona. Most or allof the lar ge ma ar s and cinder cones are visible in th e Pinacate volcanic field,

and the extent of t he field as a whole is eas ily delineated. In addition, cons idera ble geologic de tai l

to the north can be identified with the aid of the Geologic Map of Yuma County, Arizona (Wilson,

1960). Contacts between Mesozoic gran ites and foliated metamorphic rocks are distinct, as are

the northward trending frac ture s just north of the Pinacate field. The fact that much of the detai lshown on the 1:375,000 Yuma County map c an be se en on this picture, whose original scale was

about 1:2,200,000, demo nstrat es the possibility of retaining useful resolution in extremely small-

sc ale photographs.

Figure 4 was taken in the 32nd revolution sequence, over southern New Mexico. It demon

st ra tes two potential geologic use s of hyperaltitude photography. The first use, revision or

Figure 3-Northern Sonora, Mexico; Pinacate volca nic f ie ld (Sierra del Pinacate) . Gu lf of

Caiifornia at lower Ieft. East-West dist an ce at top of photograph about 80 m i l e s .

5



Figure 4-Northern Chihuahua, Mexico, and SGuthwe5ktti New Mexico. Cedar, Hatchet, a d

Florida Mountains. Sierra Carrizari!la (right center) i s large volcanic f i e ld .

A second potential application o f h37peraltitude ph~togr~ylhy,the study of regional tectonics,

is aiso demonstrztted by Figure 4. This picture and the tw o adsjoiningO I E B (nd hhicnvfl) make it

possible to see at a glance the transition zone betvieen the folded Mesozoic rocks of northeasternMexico (Raniirez and Acevedo, 19.57)a i d th e block-EmZted volcanics oE southwestern New kI&m

(Dane aid Bachnrm, 1364). The essential parallelism of �old Z Y ~ Bi n Chihkiaiiua afid fault-c:oritrolled

6



ranges, such as the Cedar Mountains (Bromfield and Wrucke, 1961) and Dog Mountains (Zeller,

1958) in New Mexico, indica tes consid erable contro l of the faults by pre-e-sting folds, as proposed

by Jones (1961).

Other features of geologic interest in Figure 4 are the conspicuous pediments surrounding th e

Florida, Cedar and Hatchet Mountains, and others. Being covere d by Quaternary alluvium, the se

surfaces are not delineated at al l on geologic maps, and are delineated on topographic m aps onlyto the extent tha t they refl ect topography. Hyperaltitude photographs such as Figure 4, however,

provide col or cove rage of en tir e pediments without th e degradation inhere nt in mosaics, and should

be useful in studying rela tion s between pedimentation and str uctu re, lithology, and topography.

NORTH AFRICA AN D ARABIAN PENINSULA

Figure 5, taken ove r M auritania duri ng the 12th revolution, is a good example of opportunistic

photography car rie d out during the flight. The Richat structures wer e not specifically list ed as

. ~ .~ . . -. . . ..̂ - . . .. .. ..' I ..

. . ... .

Figure 5-Richat structures, Mauritania; north at lower left. Smaller structure is ivst above and

left of spac ecraft nose.

9



subjects, although the crew had been asked to Iook fo r any large cii-eu1a.i-features which might !IC

the roots of impact structures. The Richat structures are of consfderat3le interest b e c : ~ ~ ~of the

reported discovery of coesite in breccia from the center of th e large feature by CailI~ux,et all.

(1964). This picture throws no obvious light on the pmblem of origin, but is of value in demonstrzt

ing the ability of hyperaltitude photography to show large strunturea in their entirety and in relatioli

to surrounding areas.

Figure 6 shows a portion of the Tibesti Mountains i n the Republic of Chad, hSc3ri.h Africa,;

the cra ter at left center is Emi Koussi, a recent volcai~o. Although not t;&en tinder optimurtl

conditions-note, fo r example, the sca tter ed light on the window and the extrem e foreshoriening

this picture is of considerable geologic int ere st. The concentric patte rn i n the fi?reg~otnnd,a

combination of fr act ur es and longitudinal sand dunes, is not shown in its entirety on cvrjn the

latest topographic maps of the area (the Largeau 1:1,000,000 sheet, lnstitut G6ographic National,

Paris, 1961), no r is there any kiiown mention of it in recent geologic refercnces (Gcrard, 1358).

This pictur e again demons trates the usefulness of hyperaltitude photography in studying regiomi.

fracture patterns, as suggested by Lrmman (1964) and Morrison and Chowivri (1964).

Another fe atu re not previo usly mentioned in the geological l i terature i s the circidlar structure

below and to the right of Erni Koussi (110 kilometers S, 42"W of Em i Koussi). It appr:trs to he 8

ser ies of concentric ridges, with a rnaximum d iamet er of 18 kilometers, in what Gc r ~ r d(1958)

shows as Upper Devonian sandstone. The nea rne ss of the ~ t r u c t ~ r eto the Quaternary vofcasiics of

the Tibesti Mountains suggests an igneous origin (e.g., 5 laccolith) for it . Ikwerer, its simllzritp

to probable fossil impact str uctures such as the Clearwater Lakes (Dence, 1965) and to the Richat

structu res suggests that this possibility be investigated.

Figures 7, 8, and 9 are an overlapping s er ie s taken i n drifting flight durin g the 24th rmolu

tion over Yemen and the Aden Prote ctorat e, in the southwest part of the Arabiari Peninsula. They

scale (see "Geologic Map of the Arabian Peninsula, 1:2,000,006; 1963; U.S. Geological Surwg).

The area shown i n Figure 7 is underlain chiefly by Pre camb rian gran ite gneiss (to the north)

and Upper Jurassic limestones, masls, aid shales, separated by a inajor norm al fault, accordjig

to the USGS 1:2,000,000 map The fault is eLupresscdby what may be a n erosional scarp, judging

from the presumed relative resistance of th e two major rock types. This pic ture would ap pear

be of great value i n studying the s tru ctur e of the are a: in addition to the fzult ahown on the map$

se ve ra l dir ecti ons of jointing and faulting riot shown are obvious. The a3luvium/bedrock contact

could also be delineated more preciaeiy.

Figures 8 and 9 are oblique views to th e sou theast. In addition to th e strueture of Pi-eearnbrfm

ar ea s in the foreground (also covered by Figure 7) ai d top center, they sfiow an extensive field of

longitudinal dunes i n the Empty Quarter. The dunes appear similar to those in the Sdiarn Desert

Eclassified as "complex longitudinal" dunes by Smith (1963). The se photographs prov ide ~ U excellent

ov er sli view of the dune field permitting, fo r example, study of changes in rnorphology as a funetlon

of distance from the crystallin e highlands. The availability of color photographs, whose potential.

value in dune studies is cited by Smith (19631,adds to the usefulness of hyperaltitude photography.



_ -

Figure 6-Tibesti Mountains, Republic of Chad; view to northwest. Prominent cra ter in

mountains (left center) is Em i Koussi, highest poin t in Sah ara Desert.

9



Figure 9-Southwestern part of Arabian Peninsula, just ea st of Figure 8; se i f dunes in

Empty Quarter. Northern ed ge of Hadramaut Plateau in background.

Figure 10 shows the east ern end of the Arabian peninsula. The shoreline at fa r right (arrow)

is that used in the edge analysis described previously. The land area shown is underlain by a

variet y of T ert ia ry and Cretaceous sedi mentary rock; the linear ridges at lower left are sand

dunes.

Figure 11w a s taken over th e south ern pa rt of th e Arabian Peninsula, looking over the Hadra

maut Plateau toward the Gulf of Aden. It provides an excellent example of stre am piracy (arrow),

in which one st re am (the Wadi Adim) ha s cut headward under stru ctu ral influence and intercepted

the headwaters of other streams (such as the Wadi a l Ayn); these wadis are now usually dry. It is

interesting to note that this feature is not apparent on the 1:2,000,000 scale Geologic Map of th e

Arabian Peninsula, although this scale is larg er than that of the origin al Gemini photograph. The

picture is als o of interes t as a striking example of a dendritic drainage pattern ina morphologi

cally youthful region.

11



Figure TO-Eastern end of the Arabian Peninsu[a; Ras a1 Wadd at fu r right.

Linear features a i lower left ure the Wahibah Sands, a large dune f i e ld .Mountains underlain by Cretaceous and Tertiary igneous and sedimentary

rocks.



NORTH

Figure 11-View to southeast over the Hadramauf Plateau, showing th e

Hadramaut Wadi,a dendri tic drainage pattern of canyons. Plateau is under

lain by near ly flat-lying or gentiy dipping Cenozoic sedimentary rocks.

ACKNOWLEDGMENTS

This experiment and th e interpretat ion of th e photographs req uire d the help of many people.

We are especially grateful to the following: R. D. Me rce r, Manned Spac ecraft Center, mo nitor for

the S-5 and S-6 experiments; W. A Fischer, P. B. King, L. C. Conant and S. J. Gawarecki, U. S.

Geological Survey. Per son nel of th e U. S. Geological Survey Li bra ry were most helpful in litera

tur e search es. Ing. Guillermo P. Salas, D irec tor of th e Geological Insti tute of Mexico, provided

13



much valuable information. K M. Na g l e r and S. D. Soules, National Weather Sa tell ite Center,

principal investigators for the S- 6 Synoptic Weather Photography experiment, worked close ly with

the authors in i nterpreting th e photographs.

Goddard Space Flight Center

National Aeronautics and Space Administration

Greenbelt, Maryland, October 14, 1966

185-42-01-02-51

REFERENCES

1. Allen, C. R., Silver, L. T., and Stehli, F. G., "Agua Blanca Fault-A Major Transverse Structure

of Northern Baja California , Mexico," Geol. Soc. Amer ica Bull. 71: 457- 482, April, 1960,

2. Beal, C. H., "Reconnaissance of the Geology and Oil Possib ili tie s of Ba ja California, Mexico,"

Geol. Soc. Ame rica Memoir 31: 1948.

3. Bromfield, C. S., and Wrucke, C. T., Reconnaissance Geologic Map of the Cedar Mountains,

Grant and Lunar Counties, New Mexico (Scale 1:62,500): Mineral Investigations Field Studies

Map MF-159, 1961.

4. Cailleux, A ., Guillemaut, A., and Pomerol, C., "Presence de coesite, indice de haute pressions,

dans l'accident cir cul air e de Richat (Adrar mauritanien)," Compt. Rend. 258: 5488- 5490, June,

1964.

5. Dane, C. H . , and Bachman, G. O., Geologic Map of New Mexico (Scale 1:500,000): U. S. Geo

logical Survey, Washington, D. C., 1965.

6. Dence, M. R., "The Extraterrestrial Origin of CanadianCraters," 941-969, in Geological

Problems in Lunar Research, J. Green, editor, Annals of the New York Academy of Sciences,

123: art. 2, 367-1257, 1965.

7. Gerard, F., Carte geologique d e 1'Afrique Equatorial e Fra nca ise au 1/2,000,000: Governement

General de 1'Afrique Equatoriale Francaise, Direction des Mines et de la Geologie, Paris, 1958.

8. Gettys, R. F., "Evaluation of Color Photos Exposed fro m the Gemini (GT-4) Flight ov er the Gulf

of Californ ia," Unpublished manu script, Technical Prod uction Department, U. S. Naval Oceano

graphic Office, Washington, D. C., 1965.

9. Gill, J. R., and Gerathewohl, S. J., "The Gemini Science Prog ram ," Astronautics and Aero

nautics 2(11):58-65, 1965.

10 . Jones, R. W., "Structural Evol.ution of Part of So utheastern Arizona (Abstrac t)," Am. Assoc.

Petrol. Geol. Bull. 45(3):413, March, 1961.

11 . Lowman, P. D., Jr., "A Review of Photography of the Earth from Sounding Rocket s and Satel

lites," NASA Techn ica l Note D-1868, 1964.

14



12 . Moody, J. D., and Hill, M. J. , "Wrench-Fault Tectonics," Geol. SOC.America Bull. 67:1207-1246,

September, 1956.

13 . Morrison, A , and Chown, M. C., "Photography of the Wester n Saha ra Dese rt fr om the Mercu ry

MA- 4 Spacecraft," NASA Contractor R eport CR- 126, 1964.

14 . Na g l e r , K. M., and Soules, S. D., "Cloud Photography from the Gemini 4 Spaceflight," Bull. Am.

Meteorological SOC.46(9):522-527, 1965.

15 . Ramirez, J. C., and Acevedo, F., "Notas sobre la Geologia de Chihuahua," Boletin de la Asocia

cion Mexicana De Geologos Petro leros IX(9,10):583-770, 1957.

16 . Smith, H. T. U., "EolianGeomorphology, Wind Direc tion , and Climat ic Change in North Africa,"

AFCRL - 63 - 443, Geophysics Rese arch Directora te, Air Forc e Cambridge Research Labora

tories, Bedford, Massachusetts, 1963.

17 . Wilson, E. D., Geologic Map of Yuma County, Arizona (Scale 1:375,000): Arizona Bureau of

Mines, University of Arizona, Tucson, Arizona, 1960.

18 . Zeller, R. A., Jr., ReconnaissanceGeologic Map of Dog Mountain Quadrangle (Scale 1:62,500):

Geologic Map 8, Sta te Bureau of Mines and Min eral Resou rce s, Socorro, New Mexico, 1948.

19. Data Corporation, Dayton, Ohio, "Edge Analysis of Gemini 4 Color Photography," unpublished

manuscript, 1965.

15 NASA-Langley, 1967-13



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