additional geographical and geological data from the polish

RYSZARD GRADZINSKI & TOMASZ JERZYKI EWICZ
AD D IT IONAL GE OG RAPH ICAL AND GEOL OG ICAL DATA FROM
THE POLI SH -MONGO LIAN PALAEONTOL OG ICAL EXPED ITI ON S
(Plate Il l)
Abstract. - The local ities. at wh ich th e field work of th e Polish-M ong o lian Palae ont ol ogical Expeditio ns was ca rried
o ut in 1970 and 1971 a re described. Th e po sit ion and morphology of the localiti es a nd geo logical pr ofiles are given .
On sehema t ic map s and gene ral ized profiles. the main foss iliferous sites are show n.
INTRODU CTIO N
The Polish-Mongol ian Palaeontological E xpediti on s o rga nized in 1970 a nd 1971 carried
out field -work at Bayn-D za k, Toogreeg, Khermeen T sa v and in the Nemegt Ba sin ( K IELANJAWOROWSKA & BARsBo LD , 1972) . In the Nemegt Basin fo ssils were prosp ected and excavated
in Upper Cretaceous deposit s (in t he Upper and Lower Nemegt Beds). In 1970 th e investigations
were concentrated in the region o f the locality Nemegt and their geologica l description is due
to the first a uthor.
In 1971 the excavatory work wa s cont inued in th e Nemegt Basin in the loca lities of
Khulsan , Nemegt, Alta n U la 11 , III and I V. In the locality of Toogreeg sit ua ted north-east
from the Ne megt Ba sin the excavatory work ha s been a lso performed . The locality of K hermeen Tsav sit uated so ut h-westward from the Nemegt Basin ha s been only visited. T he geological description of the localities prospected in 197 1 is due to tire seco nd author.
The present de scription form s a continuation of a paper by GRADZINSK I et al. ( 1968/69)
and sho uld be read in conj unction with that paper. It contains data concerning the po sition
of the excavation sites worked in 1970 a nd 1971. Only so me geological data a re presented,
and to some extent supplement th e earlier publicati ons (G RA DZINS KI et al.. 1968/69; GRADZINSKI , 1970) . The re sults of sed imentologica l in vestigations of the Lower N emegt Beds carried out during the 1970 and 1971 exped itio ns will be published sepa ra tely.
The geological profiles were drawn on the ba sis of detailed profiles, but th ey a re generalized
in most cases, and present an o verall picture of th e lithology of the beds in part icular o utcro ps .
Different resistance to weathering of particular beds is reflected in the m orphol ogy o f slo pes .
The maps of the localities were made with the use of the mea suring instrument .T eletop"
of Zei ss Co. a nd of a geological co m pass "Meridian ". The locations of th e individual specimens
and a rea s of detai led prospecti on are marked by numbers on the m aps a nd o n the profiles.
2 - Palaeon tologia Poloniea N o . 2i
A lJ Dl TlONA L GE OG RA PH ICAL AN D G EO LOG ICAL DATA
If\ f\ /\ I ISOLATED H I LLS
~ L A RGER CLI F F S
ca
CLI FF S
1~,,/\./1
SLOPE
lllll\~ INTERCONNECTING GORGES
~ SAY R
o
CAIRN
00 FAUNA
o
EXCAVATED
~ CAMP
::0
o
1k m
I
!
L-
._ .
- -- - --
-
-
-
-
-
-
-
- - --
-
-
-
-
Fig. I
-
-
-
-
--
- -- " -
-i>
Map of northe rn par t of local ity Nemegt. Excavated fauna indicated by numbers : 12 - incomplete skeleto n with pa rt
of the skull of Tarbosaurus bataar (part of the skeleto n was excav ated in 1965, see GRADZl r:,;SKl er al., 1968/69, Te xt-fig. 2) ;
RYSZARD GRADZ INSK I & TOMASZ JERZYKI EWI CZ
19
ACKNOWLEDGEM ENTS
Tha nks are due to Dr. R. BARSBOLD (Laboratory of Stratigraphy a nd Paleontology,
Acade my of Sciences of the Mongolian People's Repub lic, Ulan Bator), to Dr. V. ZHEGALLO
an d D r. V. J. RESHETOV (Palaeontological Institute of the Academy of Sciences of USSR)
for supplying information concerning the locality of Khermeen Tsav and for friendly cooperation.
LOCALIT Y NE MEGT
This locality name was introdu ced previously (GRADZINSKI et al., 1968/69) to denote
a large gro up of exposures situated on the northern pediment of the Nemegt Basin, SSE of
the Kh obo or Mt. (2768 m). T he exposures are situated 12-1 8 km south of the margin of the
Nemegt Massif, a nd are concentra ted aro und several la rge sayrs, viz. the Western , Centra l,
Northern a nd Eas tern Sayr. All these join into one Broad Sayr which is a tributa ry of the
main sayr of the Nemegt Basin extendi ng in the E-W direction. The excava tio ns ca rried out
by the 1964 an d 1965 expeditions were co ncentra ted in the centra l part of the expos ures of
th is locality. During the 1970 expedition the nor thern part of the Nemeg t locality was worke d,
while pros pection for fossil mammals was carried out in 1970 a nd 1971 in its south-eastern
part. For practical reasons these two regions are described below separately.
Northern part of Nemegt locality
The area of excavations carried out in 1970 is shown in Text-fig. I. T his area adjo ins
directl y from N and NW the area of work s of the 1964 and 1965 expeditions, the plan of which
was publishe d earlier (GRADZINSK I et al., 1968/69, Text-fig, 2). The area described here lies
between 10Ic02'-101 003'30" longitude E' and 43°30'30 "-43°32'30 " latitude N, at altit ude
1550- 1600 m above sea level.
In the area shown on the plan , the older pediment is dissected by two large sayrs, named
previo usly the Northern Sayr and the Western Sayr. The floor of the first one lies ea. 45 m
below the older pediment surface. The sayr bed is 10- 40 m wide an d accessible for field motor
vehicles on the whole area shown on the plan. Rock terraces bordering the sayr bed on both
sides are up to 25 m high and dissected by numerous smaller gorges . The latt er are usually
narrow a nd mostly inaccessible for motor vehicles. The lower part of the valley of the Northern
Sayr (beginning with the Red Field) is relatively na rrow a nd bordered by high. genera lly
vertical walls. Farther north it widens into a large depress ion. then agai n it na rrows (nea r
the Isolated Hill), and then widens agai n. The Isolated Hill lies approxi mately in the centre
13 - fragment of t he postcranial ske leto n of th e coe luro id dinosaur ; I4 - complete postcrani a l skeleto n of or nithomimi d din osaur ; 15 - to rtoise ; 16 - tortoise ; / 7 - sk ull of a tort o ise ; / 8 - fish remains ; 19 - skull and fragments
of the postcrani al skeleton of pach yceph alosaurid dinosa ur ; 20 - pelvis of o rn itho m im id dinosaur ; 2/ - fra gme nts
of the limb s of o rni tho mi mid din osaur ; 22 - torto ise; 23 - inco mplete backbon e, fragm ent s o f th e pelvis and tar sus
of S aurolophus angustirostris: 24 - incomplete ske leto n with th e fragmentary skull of Tarbosaurus bataar; 25 - pelvis
of o rn itho mimid din osaur ; 26 - fragment s of th e postcrani al ske leto n of coeluroid din osaur ; 27 - fra gments of the
ta il a nd hind limbs o f Sau rolophu s angustirostris; 28 - fra gmenta ry sk ull and postcrani al ske leto n of Su urolophus all gustirostris; 29 - incomplete skull a nd frag ments of the backbon e of Tarbosaurus bataar: 30 - seven vertebrae and
fragm ent s of the metat ar au s of Tarbosaurus batuar; 3/ - fragment ary tail , pelvis and hind limb of Tarbosaurus bataar ;
32 - mud sto ne with ost racods , cha race an s and pelecypods.
20
RYSZA RD GRADZINSKI & TOMASZ JERZ YKI EWI CZ
of thi s wide sect io n of th e say r va lley . A depression in the surface o f th e o lde r pediment is
sit ua ted immed iately to th e so uth . From th at place th e Western Sayr ex te nds so ut hwa rd .
The large Vip er Sayr is situa ted immed iat ely east o f th e Northern Sayr . These two say rs
j oin at the Red F ield. Th e sho rt but deep G oat Sayr is sit ua ted bet ween th e two say rs de scribed
a bove in the so uthe rn part of th e a rea.
The exp os ures sit ua ted wit hin th e Wes te rn Sayr form th e wes te rn peripher y o f the
Nemegt locality. Farther west ext ends the surface of th e o lde r ped iment covered by very shallow
sayr bed s. The Western Sayr j oin s th e Central Say r near th e ca m p site o f th e 1964 exped it io n
(see T ext-fi g. 2 in GRADZINSKI et al.. 1968/69). Thi s say r is ac cess ible fo r field mot o r ve hicles
on its entire length . Numer ous a nd fairl y ex te ns ive ex pos ures a re gr ouped in th e northern
part of the We stern Sayr (i. e. in th e a rea shown o n th e plan , Text-fi g. I ). The flo or o f th e
sayr is lying 25-30 m below th e su rface o f th e o lde r pediment.
Resear ches in 1970
The 1970 exp edition worked a t the loc ality Nem egt in the area sho wn on the plan (T extfig. I; see a lso T ext-fi g. 2). Moreo ver , prosp ect ion for s keleto ns wa s carried o ut in the northern
part of the Viper Sayr and in th e northern part o f th e Ce ntra l Sayr , west o f the Great Pyramid
(see GRADZINSKI et al., 1968/69, T ext-fi g. 2).
o
o
W
W
CD
' ~_._ . . r-®--@
.:: .. '<.' :'-: ':<':: . ----@@
u
~
INTRAF ORMAlIONAL
CONGLOME RA TE
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SAND STONE
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.....
....
...
SA ND
GRAVE LS
~
CLAYSTONE
IMUDSTONE )
W
~
SI LT. SILTSTONE
a:::
W
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SAN DS WIT H SILT
INTE RCALATIONS
u
z
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w
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,
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w
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4W
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Fig . :2
Geological profile of Uppcr Cre taceous sediments at northern part of
see Text-fig. I.
ernegt loca lity. For expla na tion of numbers
ADDITIO NA L GEOG RA PHICA L AND GEOLOGICA L DATA
21
Geology
The exca vations in the northern part of the locality Nemegt were carried out only in
the Upper Nemegt Beds. These bed s were described elsewhere (GRADZINSKI et al. , 1968/69,
pp. 40-42; GRADZINSKI , 1970). The deposit s of th e Passage Serie s and of the overlying beds
a re exposed in th e region of the Northern Sayr in the are a sho wn on the plan (Text-fig. I).
Thei r total exposed th ickness amounts to ea. 40 m. Only the bed s o verlyin g th e Pa ssage series
are exposed in th e Western Sayr ; their visibl e thickness amounts to ea . 30 m.
All of the 15 fragments of dinosaur skeleto ns excavated in thi s locality a t sites shown
on the plan were found , with one exceptio n, in sa ndy deposits. In four ca ses the bones occurred
in fine-grained sa nd s with inclined stratification. In th e rem aining cases the dinosaur bones
were found in fine- and medium-grained sa nds, containing sigle siltsto ne fragment s or thin
len ses of intraformational conglom er ates. Onl y the specimen of Sa uroloplius angustirostris
(No. 28) occurred partly in a sa ndy deposit a nd partly (a min or part of th e skeleto n only)
in siltstone. This part of th e skeleto n was in a distinctly poorer sta te of pre ser vation.
Observat ion s carried out during th e 1970 expeditio n suggest that in the region of the
Viper Sayr within the Passage Seri es th e deposit s of the lithological type of the U pper Nemegt
Bed s pa ss lat erally into deposits of th e Lower Nemegt Bed s type . In th e regio n of the Northern
Sayr and in the northern part of the Central Sayr fairl y num erous sma ll gastropod shell s
and fish rem ain s were found in sa ndy siltsto nes.
Detailed ob serv ations led to the conclusion that trace fossils pre sent in th e U pper Nemegt
Bed s a re in fact more di versified th an it was described by GRADZINSKI (1970 , p. 222).
SO UTH-EASTERN PART OF TH E LOCALITY NEMEGT
Location and morphology
Prospection for fa una wa s carried o ut in th is part of th e locality Nem egt in two areas
(Text-fig. 3). The first on e comprises the so uthern slo pes of the Red Wall s and the isolated
hill s sit ua ted immediately sout h-east a nd called Red M onadnocks. This area is shown by
GRADZINSKI et al . (1968 /69 , Text-fig. 2). Appro ximate geog ra phic coordinate s of thi s area
are : 101°4 ' longitude E and 43°30'20" latitude N, and the a ltit ude is c. 1500 m above sea level.
The described hill s are situated in th e northern part of th e Sak saool Field extending NW-SE.
Their height amounts to 10-20 m a nd the slopes a rc st ro ngly di ssect ed by sma ll eros io na l
form s.
Th e second prospected area co m prises the iso lated hills call ed Southern Monadnocks,
situated 3-4 km SSE of the Red Walls, near th e conjunction of the Western , Northern and
Eastern Sayrs into on e Broad Sayr. Th e majority of the se hill s lie eas t of thi s say r. The approximate geographic coordinates of thi s area a re 10 I05' longitude E and 43°29' latitude N,
and the altitude is ea . 1450 m above sea level. Th e height of the hill s above the floor of the
sayrs ranges from 10 to 35 m. The slo pes of th e hills are dissected by numerous erosional
form s : furrow s, sho rt ravines a nd recesses.
22
R YSZA RD G RA DZ INS K I & TOMASZ J ERZYK IEW ICZ
Fig. 3
Map o f so uth-eas tern part of localit y N crncgt . For mo rpho logica l explanat ion
sec Text-fig . I.
Geology
Fi rst prospe ct ion for fa una was carried out in th ese a rea s in 1965 (see GR AD ZI NSKI et al.,
1968/69 , p. 40), wo rk was continued 1970 a nd 1971 . In Southern a nd Red M o naan ocks mamm al
skulls, lizards, d inosau r eggs a nd tort oise rem ains ( MLY NARS KI , 1972) were fo und .
A D D ITIONAL GEOG RA PH ICAL AND GE OL OG ICAL DAT A
23
Lower Nemegt Bed s a re exposed in the so uth-ea stern part of the locality Nemegt (GRAet al.. 1968/69: GRAD ZI NSKI, 1970). They co nsist of fine-grained poo rly cemented
sa nds to nes with rare int ercalati on s of sa ndy mud ston es. The sa ndsto nes ha ve usually a br ick-red
co lo ur, while th e mud ston es a re o f a so mewhat da rker redd ish-brown co lo ur.
A fairl y d istinct thi ck hor izontal beddin g is visible in th e Lo wer Nerncgt Bed s near
th e Red Wall s. Large-scale tabular cro ss-bedded unit s (lim its fo r size cla sses o f cro ss-bedding
units a fte r GR UMBT 1969) a re pre sent in o utc ro ps situated farth er so ut h (So uthe rn Monadn ock s), beside thick hori zontally layered o r ma ssive sa nds to ne bed s. Numerous beds or
red-brown siltsto nes a lte rna ting with sa nds to ne bed s a re present in the bluffs in th e eastern
part of the Southern Mon adn ock s. Th e upper surfaces of th ese silts to ne bed s are often loaddeformed, a nd so metimes a total di sruption of sa ndsto ne bed s sepa rating the siltsto nes has
led to the formation of isol at ed o blo ng sa nds to ne bodies and ball s inside th e silts to nes (see
DZI NSKI
A NKETELL et al., 1970).
LOCALITY KH ULSAN
Location and morphology
The exposures a t thi s local ity a re sit ua ted c. 6 km ESE of th e locality Nemegt. Some
of th em ha ve been design at ed as "E Nernegt " by GR ADZI NSKI ( 1970, Text-fig. I). Presently
th ese ex pos ures a rc give n a sepa ra te nam e der ived fro m a near-byclosed depression . The major
part of the exposures is concentrated in th e a rea wit h coordinates 10I°07'- 10 I°09' longitude E
a nd 43°28'-43°30' lat itude N, at a n a ltit ude of 1400-1450 m above sea level. The exposures
ar e sit uated on th e slo pes of Bro ad Sayr va lley. Th is broad sayr design ated a s the Main Sayr
(see Text-fig. 4) run s approxi ma te ly North-South , is j o ined by severa l smaller ones, and turns
to ESE in the so uthern part of th e di scu ssed a rea . The va lley of the Main Sayr is asymmetric.
East of the Main Sayr the slo pes are gentle a nd co vered by an almos t continuous blanket
of recent de sert sed ime nt. Outcrops of Cretaceou s rock s in thi s part of th e locality are small
and rare.
The western slo pes of the Khul san Valle y ha ve a more div er sified morphology. The
older pediment ha s been dis sected by numerou s sma ller sayrs which join the Main Sayr from
the North-West. A part of the western slo pe of the Khul san Valle y is sepa rated from the older
pediment by a continuous escarpment up to 25 m high. Differentiated erosional retreat of this
escarpment to the N orth-West ha s led to the form ation of numerou s ravin es with wall formed
of Cretaceous sa nds to nes . Small tabl e mountain s p reserv ed in front of the esca rpment have
the top surfaces co ver ed by desert pavem ent whil e smaller mound-shaped isolated hill s with
steep walls are entirely co mposed of Cretaceous sa nds to nes. They form a ch aracteristic morphologic element of the Khulsan locality (P I. Ill , F ig. I).
Geology
At the Khulsan local ity occ ur the Lo wer Nemegt beds de veloped as pale- red, fine-grained
sandstones with ra re interca latio ns of red-bro wn siltsto nes (Te xt-fig . 5). Conglomerates are
rare, and consist chi efly of intrabasinal pebbles of redeposited siltstones. Cherts and effusive
rock s predominate amo ng exo tic pebbles, The pebbl es a re di spersed within the sa ndstone
24
R YSZA RD G RA DZ I SKI & TO MA SZ J E RZY KI EWICZ
::
,\ I~
/ / ,'
, \ f.,.. --;
'" ~%
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;;\ I ~
' I'
o1
-
l km
I
Fig. 4
Ma p of localit y Khu lsan. For mor phological explana tion see Text-fig. I. Excava ted fa una indicated by number s : 1 lower jaw o f Prot ocerutops sp. : 2 - fragm entary skeleton of a sma ll theropo d dinosa ur ; 3 - skeleto n of a lizard :
4 and 5 - two skulls of sma ll ind ividua ls o f Prot ocerat ops sp. : 6 - part ia l sk ull of an ankylosau rid d inosaur ; 7 tortoi se : 8 - par tial skeleton of a sma ll thero pod din osa ur : 9 - severa l sku lls and par tia l postcranial skeleto ns of
amphislaenid lizard s : 10 - skull of a pach yceph alo saurid dinosaur ; 11 - a skeleto n wit h skull of an ankylosaurid
din osaur ; 12 - skeleton o f a lizard .
25
ADDITIONAL GEOGRAPHICAL AND GEOLOGICAL DATA
bed s or form agglomerations with indistinct boundaries. Occasionally the pebbles are con centrated within erosional channels.
The sandstone bed s are ma ssive, horizontally st ratified or cross-stratified. Tabular crossstratification is present in thick bed s, while through cross-stratification (see McK EE & W EIR,
1953) occurs in thinner one s.
B
A
GRAVEL OR CONGLOMERATE
V.:·<·. :·']
SAND OR SANDSTONE (MASSIVE
p·t::<.:l SAND
rill
!Ill
OR HORIZONTAL
BEDDED)
OR SANDSTONE (CROSS - BEDDED)
SILTSTONE
OR CLAYSTONE
SILTSTONE
OR CLAYSTONE
WITH
LOAD
STRUCTUR E:'
Fig. 5
Geol ogical profile s of Upper C retaceo us scd irncnts of Khul san localit y. Fo r exp lana tion of numbers see Text-fig. 4.
The siItstone beds are ranging in thickness from severa l cm up to ea. 50 cm. Usually
the y are wedging out on the length of several ten s of metres, and sometimes the upper surfaces
of bed s display distinct wash-outs. Besides the deformational st ructures mentioned in th e
description of the siItsto nes from the Southern Monadnocks locality, desiccation cracks are
locally present on the upper surfaces of siltstone beds. Numerous examples of these structures
occur in the vicinity of Northern Cliffs.
The Lower Nemegt Beds exposed in the Khulsan locality are usually po orl y cemented.
Zones of calcareous cementation are rare and occur in the form of tough sa ndstone beds,
or as o val-shaped bodies of tough sa ndsto ne reaching a few m in diameter distinctly sta nding
out in semi-loose sa nds to ne. Small white calcareous concretions a re much more commom .
One short reconnai ssance of the a rea with no posit ive results wa s carried out in 1965.
During 1970 and 197I expeditions the skull of pachycephalosaurid dinosaur, the skull with
the anterior part of the trunk of an ankylosaurid dinosaur, numerous lizards, tortoises skulls
of mammals, diplopodes and dinosaur eggs were found in thi s loc ality.
26
R YSZARD G RA DZ lN SK l & TO MASZ J ER Z YKl EWlCZ
LO CALITY KHERMEEN TSAV
Location and morphology
T he Kh ermecn T sav Valley forms o ne of the larg est a rea s of exposure of Cr etaceous
rocks known in Mongolia. It lies South-West of the Nemegt Basin. The coordinates of th e
central part of th e valley are approximately 99°45' longitude E and 43°15' latitude N. The
altitude is ea . [200 m above sea level.
The pedim ent is dissected here by very numer ou s sayrs coalescing into a large valley
extending WNW-ESE (Text-fig. 6). Th e width of the valley between the Northern Outcrops
and th e Southern Outcrops is ea. 5 km. Th e length of the largest say r de signated as the Central
Sayr exceeds 15 km. Th e depth of th e Khermeen T sa v valley measured along the profile A
(see design ation on Text-fig. 7) a mo unts to ca . 100 m.
Th e morphol ogy of the Kh erm een T sav Valley is diversified (PI. Ill , Fig. 2). The main
valley branches into num erous ra vines with steep wall s and mino r- valleys with step-shaped
slopes. Mon adn ock s of various sizes a nd usually steep slopes are common . The top sur faces
of th e m on adnocks lyin g at var io us altitudes. a nd th e co rresponding flat zones on the valley
slopes clearl y indi cat e severa l ph ases of eros ion.
2km
I
®
PEDIMENT
Fig . 6
Ske tch-map of localities Kh ermeen Tsav I a nd [I. Design at ion s: A, B, C correspo nd to geo logica l p rofiles in
Text-fig. 7. For morp ho logica l ex plana tion sce Te xt-fig. I.
History of research
Kh ermeen Tsav valley has been di scovered by D r. R . B ARSBOLD a nd Dr. V. S. Z HEin 1969 durin g the work of th e Soviet-Mongolian Palaeontological Expedition. The
member s of the P olish-M on golian Ex pedition visited thi s locality in 1971 at three occasio ns.
GAL LO
ADDITIONAL G EOGRAPHICAL AND GEOLOGICAL DATA
27
During these excursions Cretaceous sed iments exposed so me 10 km North-East of the Central
Sayr of Khermeen Tsav I were di scovered and prospected. We de signated these o utc ro ps
Khermeen Tsav 11 (see Text-fig, 6).
Geology
The slopes of the Khermeen T sav Valle y are built of three lithologic complexes : th e
Lower White Beds, which form the ba se of the exposed seq uence, and cr opp o ut in the Central
Sayr on a st retch of ea . 1.5 km ; the Red Beds, forming the middle part of the slo pes along
the entire va lley, and the Upper White bed s, forming the upper part of the slopes in the central
and eastern part of the valley (see Text-fig, 7). All these complexes are lying nearly horizontally.
The Lower White Beds are ea . 30 m thick and consist of alternating sa nds to nes , siltsto nes and conglomerates . The bed thickness ranges from severa l ten s o f cm to 2 m. The sa nd sto nes are usually trough-cross st rat ified. The dimen sions of the cross-stratification range
from ripple to medium scale . As a rule, the sandstone bed s are wedge-shaped . Set s of sandston e
bed s are alternating with thinner beds of siltsto nes and of intraformational conglomerates.
The top and ba se su rfaces of the silt stone bed s are sha rply marked . Wa sh-outs and load deformation s are common and the bed s a re rapidly wedging out. Layers and len ses of con glomerates with undi stinct outlines occur either within , or at the ba se of sa nds to ne bed s. The
conglomerates consist of intrabasinal pebbles. The largest pebbles up to 30 cm in diameter
are composed of red-brown silts to nes, while pebbles of sa nd sto ne, and o f light-coloured siltsto ne are smaller, Various deformational st ruct ures similar to those de scribed by GRAD ZI NSKI
(1970) from the U pper Nemegt Beds are present in the Lower White Bed s. Recumbent fold s
in cross-statified sa nd sto nes and convolute lamination in siltsto nes a re the most common .
The Red Bed s are ca. 50 m thick . They differ from the underlying Lower White Beds
by the following sed imenta ry feature s: I) the sandstones predominat e markedly o ver
siltstones and conglomerates, 2) the thickness of the sa nd sto ne bed s is greater, ran ging up
to severa l m , 3) individual sa nd sto ne and silt stone beds can be traced on di stances of severa l
hundred m, 4) the bedding planes are indistinct, 5) cross-stratification , predominantly o f th e
large-scale planar type , occurs rarely; horizontally layered and ma ssive bed s are common ,
6) the conglomerates a re fine-grained and composed of pebbles of exotic rock s, intraformational
conglomerates are rare , 7) deformational st ru ct ures are rare, 8) trace fo ssils in the form of
sed iment-filled tubes are common.
The Red Beds sho w a certain degree of facial differentiation within the Khermeen T sav
locality. In the profile Khermeen T sav 11 the thick-bedded sa nds to nes are orange-col oured
and numerou s intercalations of light-coloured (white, yellow, pale-red and bluish-green)
thin-bedded silt stones and claystones are present (see Text-fig. 7, ProfileB-).
The Upper White Beds are 10-20 m thick. A bed of variegated , fine-grain ed
conglomerate, 0.5 m thick forms the ba se of these bed s (see Text-fig. 7 - profile C) . Th e
conglomerate is composed principally of poorly rounded pebbles of exotic rock s. The conglomerate is o verlain by pale-yellow, thin-bedded fine-grained sa nds to nes showing smalla nd medium-scale cross-stratification. Rare layers and len ses of intraformational conglomerates
present within the sa nd sto nes are composed of pebbles of light-coloured silts to nes.
The Polish-Mongolian Expedition in 1971 collected fo ssils onl y in R ed Bed s without
conducting the excavatory work . From these beds in both Khermeen Tsav I and Khermeen
T sav Jl num er ou s fragmentary s keleto ns of Prot oceratops sp., fr agmentary ske leto ns of sma ll
2X
RY SZARD G RA D Z IN SK I & T O M A SZ JERZYKI EWICZ
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Fig. 7
Geological profiles o f Uppe r C retaceous sed iments of localities Khermeen Tsav I a nd 11. For lithological explanation
see Text-f ig. 5. The position o r the profiles A. B. C is show n on Text -fig. 6. The a rro ws o n profiles A and B indicate the
ho rizons in which mamm als were rou nd .
ADD ITIONAL GEOGRAPHICAL AND G EOLOGI CAL DATA
29
carnivorous dinosaur, numerous dinosaur eggs, lizards and skull of mammals were collected .
The majority of fo ssils was collected from the orange sa ndsto ne in Khermeen Tsa v 11. The
preliminary investigation of mammals found in Khermeen Tsa v I and I [ led Prof. Z . KIELA NJAWOROWSKA (in KIELAN-JAwOROWSKA & BARSBOLD, [972) to the conclusion that Red Sandsto ne of Khermeen Tsa v I and 11 is contemporaneous with the Lower Nemegt Beds of Nemegt
and Khulsan , being probably of Campanian age .
LOCALITY TOOGREEG
Location and morphology
The exposures are situated North-East of the Nemegt Basin, c. 30 km WNW of Bayn
Dzak (see GRADZINSKI et al., 1968/69). The approximate coordinates of this locality are 103°20'
longitude E and 44°15' latitude N . The altitude is 1150 m above sea level.
Cretaeous sandstones are exposed here on northern and North-Western slo pes of a broad
valley. They form moderately steep slopes and low escarpments separating the valley from
the pediment (Text-fig. 8). In the central part of thi s locality small sayrs are dis secting the
North-West slope of the valley.
CAMP
.&
1971
6)
~ND
~
DUNE ~
F ig. 8
Map of localit y Toogreeg, Fo r morphological explanation. see Text-fi g. I. Excava ted fauna indicat ed by numbers : 1 skelet on of Protoceratops andrewsi : 2 - skeleton of Protocerat ops andrewsi associated with skeleton of Velociraptor
mongoliensis in a fighting position : 3 and 4 - two skulls of Protocerat ops andrewsi.
History of research
The Toogreeg locality ha s been disco vered by Dr. DASHZEWEG, who carried out there an
excavatory work in 1967. In 1969 and 1970 it wa s visited by the So viet-Mongolian Palaeontological Expedition . The Poli sh-Mongolian Expedition worked there during one week in 1971.
The expedition exca vated two skeleto ns of Protoceratops andrewsi, two skulls of the sa me
species and the skeleton of Proto eerat ops andre wsi associated with th e skeleto n of Velociraptor mongoliensis in a fighting position.
30
R YSZARD G RAD Z IN S K I & TOMASZ J ERZYKI EWI CZ
Geology
The slo pes of the Toogreeg Valle y are built of poorly cemented white, fine-grained sa ndsto nes. Megascopic sed imenta ry st r uct ures are usually absen t, and only rarely medium- or
large-scale cross-bedded units of tabular type can be seen. The sa nd sto nes contain very numerou s o val or flat bodies of tough sa nd sto ne co vered by ferrugineou s de sert varni sh and
regular horizons of ferrugineou s cementation developed within sa nds to ne bed s. These horizons
follow so metimes the planes o f cross-stratification . but in mo st ca ses are developed
independently and cross the stra t ificat io n planes.
Polish Aca demy of S ciences
l nstitut e of Geologica l Sciences
Geological Lab orat ory
Krakow, Septembe r 1971
Polish Ac ademy of Sc iences
Institut e of Geological Sc iences
Geological Lab orat ory
Wroc/a ll', September 1971
R EF ER E NC ES
A NKETEL L, J . M .. C reilA . J . & D ZULy NSKI. S. 19 70 . O n th e d efo r m at ional st ruc tures in sys te ms wi t h reve rse d den sity
g ra die n t. - Rocz nik Pol . To ll'. Gcol., 40 , 3-30 . Kr ak o w.
GRADZINSKI, R. 19 70. Sedimen tati o n of d ino sau r-bearin g U ppe r C re ta ceo us dep o sit s o f the Ne rneg t Basin , G obi Dese rt.
Result s Poli sh -M ongol. Pal aeont. Ex ped .. 11 . - Palaeont . Pol.. 2 1. 147-229, Warsza wa . G RA DZINS KI. R. , K AZMI ERCZAK, J . & LErEU J . J. 1968/69. Geog ra p hica l a nd geo log ica l data from the Poli sh -M ongolian
Pal aeont ol o gical Ex ped it io ns. Result s ... , I. - Ibidem 19, 33-8 2.
GR UMIlT, E . 1969. Beziehungen zwisc hc n K orng ro ssc, Sch ichtung. M ate r ialbestand und a ndere n sed irn c nto logisc hcn
Mcrk mal en in fein kla sti sch en Sedimenten. - Geo logic, 18. 75-99, Berl in .
KI ELAN-JAWOROWSKA, Z . & D OVCHlN. N . 1968/69. Na r ra tive o f th e Poli sh -M ongoli an Pal ae ont ol ogi cal Ex ped itio ns
1963-1 965. Result s .. ., I. - Palueont . Po!., 19, 7-30, W arsza wa .
KI ELAN-J AWOROWSKA. Z . & BARSIlOLD, R . 1972 . Na rra tive o f th e Pol ish -M ongoli an Pal ae ont ol og ical Expe d it io ns 196719 71. Result s .. .. IV. - Ibidem , 27, 5- 13.
M cK EI'. E. D . & W EIR , G . W . 1953. Te r m ino logy for st ra tifica tio n a n d cro ss-stratificati on in sed im e n ta ry ro ck s. Bull , Geol, So c. A mer ., 64, 381- 390 , New Yo rk.
M I. y:--: A RSKI. M . 19 72 . Za nge riia test ud in im o rpha n . gc n ., n . s p., a primitive land to rtoise fro m th e U p pe r Cre taceous
o f Mo ngo lia . - Result s .. ., IV. - Pa laeont. Pol., 27 , 85- 92 . W arszawa .
PLATES
Palaeontologia Polonica, No. 27, 1972
R . GRADZINSKI & T. JERZYKIEWICZ : ADDITIONAL GEOGRAPHICAL AND GEOLOGICAL DATA
PLATE III
Page
Fig. I. Locality Khu lsan - fragment of the western slope of the valley in the vicinity of the camp. Lower Nernegt
Beds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
23
Fig . 2. Localit y Khermeen Tsav I - eastern part of the valley. Nor thern outcrops in the background . . . .
26
Phot o : T. Jerzy kiew icz
Palaeontologia Polonica, No , 27, 1972
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