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NASA TECIiMCAL IMEhdORAwDUM NASA TIIEI X-58108 February 1974
THE MENDELEEV CRATER CHAIN:
A DESCRIPTION AND DISCUSSION OF ORIGIN
NATIONAL AERONAUTICS AND SPACE ADMINISTRAmdN
LYNDON B. JOHNSON SPACE CENTER
HOUSTON, TEXAS 77058
https://ntrs.nasa.gov/search.jsp?R=19740010379 2020-05-17T03:37:47+00:00Z
NASA TM X-58108
THE MENDELEEV CRATER CHAIN:
A DESCRIPTION AND DISCUSSION OF ORIGIN
Dean Eppler Lockheed Electronics Company, Inc.
Houston, Texas 77058
Grant Heiken
Hodston, Texas 77058 Lyndon B. Johnson Space Center
THE M E N D E W CRATER CHAIN:
A D3SCRIPTiON AND DISCUSSION OF OFUGIN
By Dean Eppler' and G r a n t Heiken Lyndon B. Johnson Space Center
SUMMARY
The Mendeleev c r a t e r chain formed on a l i n e a r weakness i n t h e l u n a r c rus t t h a t may have or iginated before the formation of Mendeleev Crater. l i n e s of evidence seem t o ind ica te an endogenetic or ig in : t h e symmetrical dmbbel l pa t te rn , and t h e lack of a "bird's foot" pa t t e rn and other morphological fea tures of secondary impact craters. may be t h e result of an explosive volcanic event taking place along a f a u l t subjected t o d i f f e r ing degrees of stress.
Several t h e l i n e a r t rend,
The dumbbell pa t te rn
INTRODUCTION
This study was based on photographs f r o a Lunar Orbiter I and panoramic and metric mapping cameras car r ied on t h e Apollo 16 command module. long c r a t e r chain w a s se lec ted f o r study because of i t s well-developed dumbbell shape and i ts s t ra ightness . o r ig in of t h e chain and any possible re la t ionships t o Mendeleev Crater and luna r tec tonic pa t te rns . Crater Chains 1.
A 113-kilometer-
The object ive of t h e study was t o determine t h e
This work w a s performed under NASA pro jec t S-255 (Lunar
GEOLOGY OF rm MENDELEEV CRATER AREA
Mendeleev Creter, 274 by 380 kilometers, i s located i n t h e lunar highlands a t longitude 1 4 1 O E , l a t i t u d e 7' N. numerous c r a t e r s i n a l l s tages of degradation ( f i g . 1).
The surrounding t e r r a i n is composed of
The c r a t e r f loor i s p a r t l y f i l l e d with material t h a t m a y have been pa r t ly melted during the impact event. Within t h e c r a t e r , t he re i s a var ia t ion in topography from smooth, marelike t o hummoclqr t o mountainous. co~forms t o t h a t proposed by Beds ( r e f . 1) i n a hypothesis f o r large-scale i q a c t s i n to a th i ck c rus t .
This var ia t ion
%ockheed Electronics Company, Inc. , Houston, Tex.
The western w a l l of Mendeleev has well-developed slump s t ruc tu res . s ive smooth slump deposi ts w i t h low c ra t e r density occurring along t h i s f l oo r / w a l l contact ind ica te some recent slumping. These,deposits p a r t l y embay one 20-kilometer c r a t e r and contain f resh , light-haloed impact c r a t e r s i e s s than 330 meters i n diameter. Slumping of t he other walls does not appear as w e l l developed o r as recent as t h a t of t he western w a l l . This d i f fe rence may be because of the masking e f f e c t s of e j e c t a from the c r a t e r Schuster, wnich breaches the eas te rn w a l l of Mendeleev.
Exten-
DESCRIPTION OF THE CHAIN
The 113-kilometer-long Mendeleev chain has a dumbball shape with one o r Crater more l a rge c r a t e r s a t t h e ends, joined by a l i n e of smaller c ra t e r s .
r i m s are general ly low o r absent, except where influenced by va r i a t ions in pre-crater-chain topography. The inner walls of most c r a t e r s are smooth. The craters are bowl shaped except f o r several smaller c r a t e r s t h a t are conical because of mass wastin4 off t he c r a t e r w a l l s . covers t he inner w a l l . and masks any s t ruc tu re o r layer ing t h a t might be present . There are no v i s i b l e blocks i n the c ra t e r s o r on t h e surrounding f loo r of Mendeleev ( f i g . 21.
A Xne-grained r ego i i th probably
The chain, trending N 25' E , i s o f f se t l a t e r a l l y 3.6 kilometers between Craters rmge i n diameter from 1 . 2 t o c r a t e r s 18 and 19 ( f i g s . 3 and 4) .
9 . 3 kilometers, with t h e l a rges t number occurring i n the 2- t o 3-kilometer range ( t a b l e I ) .
Superposit ional re la t ionships and c r a t e r dens i t ies ind ica te t h a t t h e c r a t e r
Lack of overla?ping deposi ts chain i n Mendeleev i s younger than t h e features t h a t surround it and probably represents t h e youngest event on the c r a t e r f loor . within individual c r a t e r groups and between adjacent c r a t e r s and t h e near ly iden t i ca l s t a t e of degradation within the chain ind ica te t h a t all the c r a t e r s may have formed contemporaneously.
Approximately 150 kilgmeters southwest of Mendeleev Crater i s another s t r a i g h t , dumbbell-shaped chain o f c r a t e r s t h a t i s 177 kilometers long. This chain t rends N 45' W across the center of a degraded, subdued c r a t e r approxi- mately 180 kilometers i n diameter.
DISCUSSION OF O R I G I N
The Mendeleev chain appears t o represent a volcanic event t h a t occurred some time after the c ra te r ing event which produced Mendeleev Crater. several olservat ions t h a t support t h i s theory. The primary evidence f o r endo- genet ic o r ig in i s t h e symmetrical dumbbell a r d the extreme l i n e a r t rend , which i s more pronounced than would be expected f o r secondary impact c r a t e r s . i n t e r i o r s of t h e c ra t e r s appear t o be mantled with fine-grained regol i th t h a t could be in te rpre ted as e j e c t a from an explosive volcanic event. Similar
There a r e
The
deposits observed around the margins of several craters within the chain give tne area a smooth, mantled appearance. f r m the crater margins.
These deposits are not visible away
Another argument against secondary origin is lack of the characterist ic "bird's-foot" Fattern and other morphologicel features of secondary craters ( ref . 2). Also, there i s nc fresh, nearby impact large enough t o produce a chain of secondaries of this magnitude. i s further evidence of a nonimpact origin.
The lack of additional secondary chains
The l inear weakness along which the Mendeleev chain developed may have been E. fault that w a s par t of the "lmar grid system" (ref. 3). trend of the chain, which i s neither radial nor concentric t o Mendeleev, is the test evidence for this observation. No structure that is both straight and non- radial t o the center of h p a c t appears t o be associated with the cratering proc- esses. impact that formed Mendeleev, thus emphasizing that the chain i s not contempo- reneous with Mendeleev.
The northeastern
The age of the chain is younger than the structures associated with the
The reason for the dumbbell shape is unresolved. The formetion of cmtral upl i f t pu l l s material away from the flanks of the crater toward the center (ref. 4). This process would lead t o tensional stress in t he rock around the edge of the crater f loor and compression i n the central upl i f t . asymmetric orientation of the preexisting fault with respect t o t h e center of cratering, the fault would be subdected t o differing degrees of stress. a subsequent episode of explosive volcanism, the result ing different ia l s t ra in mey have produced varying resistance t o magma invasion along the fault and produced the crater s ize patterns observed.
Because of the
During
c0ncLus10lvs
Relative ages determined by comparing the degree of degradation of craters in the Mendeleev crater chain with that of Mendeleev Crater indicate t h a t the chain is younger. It mey have formed on a l inear weakness in the lunar crust that originated before the formation of Mendeleev Crater. symmetrical dumbbell pattern, and the lack of a "bird's foot" pattern and other morphological features of secondary impact craters imlicate an endogene5ic origin. occurred along a fault which has been different ia l ly stressed.
The l inear t rend , the
The dumbbell pattern m v be the result of a volcanic event t ha t
Lyndon B. Johnson Space Center national Aeronautics and Space Administration
Houston, Texas, February 4, 1974 646-03-01-00-72
3
1. Beds, C. S . : Crustal Thickness and the Forms of Impact Craters. J. Geophys. Res., vol. 76, no. 23, 1971, ppe 558605595.
2 . Oberbeck, V. R . ; and Morrison, R. E.: The Secondary Crater Herringbone Pattern. Science Conference (Houston, Tex.?, Mar. 5-8, 1973), pp. 570-571.
Lunar Science IV (Abs. of papers presented at the Fourth Lunar
3. Short, Io. M.: Planetary Geology. Prentice-Hall, 1974.
4. Howard, Keith A.; Offield, T e r r y W . ; and Wilshire, H. G . : Structure of Sierra Madera, Texas, as a Guide t o Central Peaks of Lunar Craters. Soc. Am. Bull., vol. 83, no. 9, Sept. 1972, pp. 2795-2808.
Geol.
4
Crater n u b e r -
1
2
3
L
5
6
1
e 9
10
11
12
1 3
l b
15
16
18
19
20
21
22
23
2b
25
-
Clreulu; bal-abaped
Circular; conical
Xrcular; bwl-shaped
Clrcuhr; bovl-ahaped
C l r c u L r ; bwl - sbped
Circular; bal-shaped
Clreular; bwl-shaped
C l r c u l a r ; bov1-shapd
1rrwu e l l i p t i c a l ; bowl-shaped
C i r e u l u ; bwl-nhapd
I r r w u subdued; bwl-shaped
Circular; bwl-shaped
C l r c u l u ; awl-shaped
C l r e u l u ; bowl-sbapd to conical
Clrcular; boul-shaped
Irrepllar mold; s teep sided; conical
Defaud olold; 501rl- n b p d t o modemtely COUlC.1
Clrcular; bowl-aha@
Truncated c l r cu la r ; bwl-shaped
Thin po l~gona l ; a h a l l a
Truncated circular. bwl-shaped
Irregular ovold; conical
3.2
L.0
h.6
3.2
2 .0
2.8
1.6
2.2
2.2
2.4
2.b
1.2
2.b
2.b
2.0
2.0
5.6
L.O
2.8
5 . 2
3.2
3.6
3.6
9.3
LOV
Lou 011 Y . s t m side; slop. uphil l l n to crater eJseta on eastern n l d e
LOV
Lou
llisb on ueatera aide; lw a
S m e - 6
remalnlng sldss
Lou
Lav to moderately steep; nrin v i t h local t-w
Lou
Lou t o m d e r r t e u r i a ; win v i t h lad w w a p w
very l W
Lav
Lov
Lor
Indls t lnct
Lw
Lou
Moderate t o hlgh
F l a p
llme
none
none
lone
lone
none
None
None
lone
-11; Ss l t I J rounded
lone
F la t
None
-11; f l a t
Sone
lone
lone
lone
lone
lone
lone
None
lone i none
c-ta
h y be a t r i p l e t v l th 3 d k ; h0Uev.r. wall betweem 2 .pd 3 l a .I)
'lant m e r o f doublet v i t h h; lw u8ll In betreen
b e M 3
lot p u t of 3 and h
hiab M rlm
doublet
h e dcpth M 7
W l e r than 6 but v i t h equivalent depth
ti. h e l e t v u l a t i o n duc to aubfloor structure
5- l l gh t p t c h n In in t e r io r -11 d w to =s nstlw
Decpcr than U; u. 1Ut p t c b e r trend ln to 12
ippara to slope Into 11; shrllonr than 11; some l l gb t p t c h e s
Streaks o f mass-uuted a t e r l a l from 13 and rlm o f l b
Shallower than 13
M n t l l n e u n t a related t o US wasting In walls
Dullower. mre bwl- shaped than 15
:oaleaced doublet next r l m unit; p t c h e s of lw crater denslty uni t a iould rim
Rim Msked because Crn- ter Is on s l o p of r l m m1t; posnlbly coalesced t r l p l r t
Long ax16 of omld pu- a l l r l t o l o w axis of chain
soar l i a r t o Dlam pmtches on lnner d l
ne.brr of t r i p l e t v ~ t h
9 u e M 22
23 and 2!4
S U O M 22
One Impact on rim. r i n Crater h u s c a l l o p d us l l r v i th s a e u . a vasting
5
Csm - fresh slvmp deposits with low crater density
Cc - impact craters Ccf - floor material of impact craters
Ccc - chain craters
Ec - impact crater
Ecf - crater floor; flat, high crater density
lcwm - crater wall of Mendeleev
Inn
Itm
- flooded floor ridge material; line denotes ridge crest
- terrace material; forms flat, highly cratered terraces in Inn
Imf - floor material of Mendeleev
Explanat ion
Csc - secondary craters
Csl - slide material from Inn; partly f i l ls some craters
Esm - slumped crater walls
Eeh - hummocky ejecta
IC - impact crater
lsrd - shallbw rimless collapse depress ions
N-
U 0 10
km
sm
Dm
- slump material; age tmcertaiti
- material of low, domal hills, age uncertain - 7 Ridge in Eeh unit
Fault; ball on downthrown side + Shallow trough1 ike rilles
€3 Crater rim - Contact
Figure 3.- Geologic map of a portion of Mendeleet- Crater, compiled from Ap0110 16 metric and panoramic photographs.
8
0 Fl
E 3
0
NASA-JSC 9