GeolCarp_Vol64_No5_355

www.geologicacarpathica.sk

GEOLOGICA CARPATHICA

, OCTOBER 2013, 64, 5, 355—374 doi: 10.2478/geoca-2013-0024

Introduction

Distinctly bioturbated mudstones (the so-called Fleckenmer-
gel or Fleckenkalk facies or “spotted” marls and limestones)
that originated in deep-shelf environments (below the storm
wave  base)  were  widely  distributed  during  the  Early  and
Middle Jurassic in the Northern Tethys, occurring in the Betic
Cordillera, Eastern Alps, Central Western Carpathians, Pieniny
Klippen  Belt,  Dinaric  Alps,  Mecsek,  Apuseni  and  Timor
(Mišík 1959, 1964; Jacobshagen 1965; Tyszka 1994a, 2001;
Wieczorek 1995; Raucsik & Varga 2008). They were depos-
ited in intrashelf basins generated by synsedimentary tectonic
collapse of the Triassic carbonate platforms and ramps. This
collapse enhanced topographic complexity and differentiated
the  Northern  Tethys  into  tectonic  blocks  with  footwall  and
hangingwall  successions,  forming  pelagic  carbonate  plat-
forms and plateaus, barriers, and restricted basins (Bernoulli
& Jenkyns 1974; Eberli 1988; Häusler et al. 1993; Böhm et
al. 1995; Koša 1998; Jach 2002, 2005; Plašienka 2003; Sant-
antonio & Carminati 2011). The Lower Jurassic spotted de-
posits  of  the  Northern  Tethys  can  alternate  with  crinoidal
calcarenites and spiculitic limestones, but the spotted depos-
its themselves are relatively uniform in sedimentological and
taphonomic attributes, forming meters to hundreds of meters

Trace-fossil assemblages with a new ichnogenus in “spotted”

(Fleckenmergel—Fleckenkalk) deposits: a signature of

oxygen-limited benthic communities

VLADIMÍR ŠIMO

and ADAM TOMAŠOVÝCH

Geological Institute, Slovak Academy of Sciences, Dúbravská cesta 9, 840 05 Bratislava 45, Slovak Republic;

Vladimir.Simo@savba.sk; Adam.Tomasovych@savba.sk

(Manuscript received February 13, 2013; accepted in revised form June 5, 2013)

Abstract: Highly-bioturbated “spotted” limestones and marls (Fleckenmergel—Fleckenkalk facies) of the Early Jurassic,
which were deposited in broad and recurrent deep-shelf habitats of the Northern Tethys, are characterized by rare benthic
carbonate-producing macroinvertebrates. To address this paradox, we analyse trace-fossil assemblages in a  ~ 85 m-thick
succession of Pliensbachian spotted deposits (Zliechov Basin, Western Carpathians). They are dominated by infaunal and
semi-infaunal deposit-feeders, with 9 ichnogenera and pyritized tubes of the semi-infaunal foraminifer Bathysiphon, being
dominated by Chondrites, Lamellaeichnus (new ichnogenus), and Teichichnus. Lamellaeichnus, represented by a horizon-
tal basal cylindrical burrow and an upper row of stacked convex-up gutters, was produced by a mobile deposit-feeder
inhabiting shallow tiers because it is crossed by most other trace fossils. We show that the spotty appearance of the deposits
is generated by a mixture of (1) dark, organic-rich shallow- and deep-tier traces (TOC = 0.16—0.36), and (2) light grey,
organic-poor  mottled  or  structurless  sediment  (TOC = 0.09—0.22).  The  higher  TOC  in  shallow-tier  burrows  of
Lamellaeichnus demonstrates that uppermost sediment layers were affected by poor redox cycling. Such conditions
imply a limited mixed-layer depth and inefficient nutrient recycling conditioned by hypoxic bottom-waters, allowed by
poor circulation and high sedimentation rates in depocenters of the Zliechov Basin. Hypoxic conditions are further
supported  by  (1)  dominance  of  trace-fossils  produced  by  infaunal  deposit  feeders,  (2)  high  abundance  of  hypoxia-
tolerant agglutinated foraminifer Bathysiphon, and (3) high abundance of Chondrites with  ~ 0.5 mm-sized branches.
Oxygen-deficient  bottom-conditions  can  thus  simultaneously  explain  the  rarity  of  benthic  carbonate-producing
macroinvertebrates and high standing abundance of tolerant soft-shell and agglutinated organisms in spotted deposits.

Key words: Jurassic, Western Carpathians, community paleoecology, dysoxia, bioturbation, ichnofacies, trace-fossil
assemblage.

thick, well-bedded successions, with abundant trace fossils
and sponge spicules (Mišík 1964; Mišík & Rakús 1964; Jach
2002).

The spotted deposits are marked by conspicuous and dense

mottling,  ranging  from  relatively  mixed  fabric  with  indis-
tinct  dark  grey  spots  up  to  well-demarcated  dark  grey  trace
fossils that are embedded in a light grey micritic matrix, im-
plying  high  standing  density  of  burrowers.  Remarkably,
such a high abundance of soft-bodied trace-fossil producers
contrasts with a low abundance of benthic carbonate macro-
invertebrates in the spotted deposits. Skeletal packing density
of infaunal and epifaunal macrobenthic skeletal invertebrates
(e.g.  bivalves,  echinoderms,  or  brachiopods)  is  mostly  very
low  (operationally,  no  or  very  few  skeletal  remains  encoun-
tered along 5 m-long bed transects), implying the presence of
conditions that were limiting calcimass production by macro-
invertebrates.  Beds  with  relatively  frequent  bivalves,  echino-
derms,  or  brachiopods  occur  but  are  rather  scarce  at  outcrop
and formation scales (Gaździcki et al. 1979; Sulser & Furrer
2008) and skeletal-rich deposits are absent in the spotted de-
posits.  However,  this  paradox  and  the  causes  of  the  paleo-
community  structure  that  characterizes  spotted  deposits  are
poorly  explored  (Wieczorek  1995;  Uchman  &  Myczyński
2006), even when this type of habitat was highly widespread

356

ŠIMO and TOMAŠOVÝCH

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

and recurrent in environments of the Tethys during the Early
Jurassic.  Benthic  communities  preserved  in  the  Middle  Ju-
rassic  spotted  facies  imply  significant  oxygen-limitation
(Tyszka  1994a,b),  and  we  assess  whether  oxygen-limiting
conditions  also  account  for  the  structure  of  macrobenthic
communities  in  the  Lower  Jurassic  spotted  deposits  in  the
Western Carpathians. Although multiple environmental fac-
tors such as salinity, sedimentation or food supply can limit
abundance  and  productivity  of  macrobenthic  carbonate  pro-
ducers, hypoxia can be one of the most important controls de-
termining  the  functioning  of  benthic  ecosystems  (e.g.  Barras
& Twitchett 2007; Pruss et al. 2010; van de Schootbrugge et
al. 2013) and influencing whether sediments are in fact fos-
siliferous or barren (Peters 2007).

Analyses of trace fossil assemblages can add much detail to

paleoenvironmental analyses and can capture gradients in bot-
tom  oxygenation  that  are  not  detected  by  traditional  paleo-
biological, taphonomic, or sedimentologic criteria (Savrda &
Bottjer 1986, 1991; Monaco 1995; Bromley 1996; Taylor et
al.  2003;  Rajchel  &  Uchman  2012).  Although  diverse  geo-
chemical approaches can detect redox conditions in the sedi-
ment  (Zaton  et  al.  2009),  ichnofacies  analyses  allow  us  to
identify the location of redox changes in the sediment column
because  infaunal  organisms  differ  in  their  depth  penetration.
Here,  to  test  whether  environmental  variation  during  the
deposition  of  the  spotted  facies  can  be  unmasked  by  trace
fossil assemblages, we (1) describe a new and highly diagnos-
tic ichnospecies and interpret the behaviour of its producer,
(2)  analyse  temporal  changes  in  the  composition  of  trace-
fossil  assemblages  from  the  Western  Carpathians  (Zliechov
Basin), and (3) evaluate whether the trace fossil assemblages
can  be  segregated  into  distinct  assemblage  groups  and
whether they can shed light on the structure of Early Jurassic
communities preserved in the spotted deposits. We focus on
the  Pliensbachian  spotted  deposits  exposed  in  the  Skladaná
Skala section in northern parts of the Ve ká Fatra Mountains
(Zliechov Basin, Central Western Carpathians).

Paleogeography and stratigraphy of Lower

Jurassic bioturbated limestones and marls in the

Western Carpathians

The Central Western Carpathians were located on the

northern  passive  margin  of  the  Tethys  during  the  Early  Ju-
rassic, approximately at 25—30° N in the tropical climatic belt
(Thierry  2000;  Jach  2005)  (Fig. 1).  Spotted  limestones  and
marls  of  the  Sinemurian-Aalenian  age  in  the  Western  Car-
pathians were previously assigned to the “Fleckenmergel” and
“Fleckenkalk”  facies  or  to  the  Allgäu  Formation  (Rakús
1963,  1964;  Aubrecht  et  al.  2002;  Gradziński  et  al.  2004;
Schlögl  et  al.  2004).  Gaździcki  et  al.  (1979)  introduced  the
Janovky  Formation  as  a  lithostratigraphic  unit  that  encom-
passes the Sinemurian-Aalenian spotted limestones and marls
in the Western Carpathians, on the basis of the Janovky sec-
tion at Mt Havran (Mišík 1959) in the Belanské Tatry Moun-
tains. Lefeld et al. (1985) assigned the bioturbated marlstones
and  limestones  with  layers  of  spiculitic  and  crinoidal  lime-
stones of the same age and in the same region to the Sołtysia

Marlstone  Formation.  However,  even  when  spatial  and  tem-
poral variation in the proportion of calcium carbonate, in the
contribution  of  spiculitic  and  crinoidal  facies,  and  in  the
thickness  and  age  of  the  spotted  facies  is  relatively  high
(Mišík  &  Rakús  1964;  Lefeld  et  al.  1985),  these  two  forma-
tion names seem to capture the same lithostratigraphic unit.
We  thus  refer  to  the  Janovky  Formation  as  the  formation
with the spotted limestone and marly deposits in the Western
Carpathians.  This  formation  is  underlain  by  the  mixed  car-
bonate-siliciclastic  Kopienec  Formation  (Hettangian—Lower
Sinemurian)  or  sandstone-dominated  Me odoly  Formation
(Lower  Sinemurian)  at  locations  with  the  maximum  strati-
graphic range that spans the Upper Sinemurian and Aalenian.
However,  the  actual  stratigraphic  range  of  this  formation  is
frequently  smaller  owing  to  complex  horizontal  and  strati-
graphic relations with other formations. It can be horizontally
replaced  by  crinoidal  limestones,  spiculitic  limestones,  or
nodular  limestones  of  the  Adnet  Formation  (Mišík  &  Rakús
1964; Jach 2002, 2005). In the upper part, it can be replaced
by spiculitic limestones (Świńska Turnia Member of the Hu-
ciska  Formation,  Western  Tatra  Mountains),  nodular  lime-
stones (Adnet Formation, Ve ká Fatra Mountains), crinoidal
limestones (Lefeld et al. 1985), or by radiolarian limestones
of  the  Sokolica  or  Ždiar  Formations  (Lefeld  et  al.  1985;
Polák  &  Ondrejičková  1993;  Polák  et  al.  1998).  Similar
stratigraphic replacements characterize the Allgäu Formation
in the Eastern Alps (Böhm 2003).

Geographic and geological setting

Trace fossils of the Janovky Formation were primarily

studied  in  the  Skladaná  Skala  section  in  the  northernmost
parts  of  the  Ve ká  Fatra  Mountains  (Fatric  Unit,  Krížna
Nappe,  Central  Western  Carpathians).  A  new  ichnogenus
found  in  this  section  was  also  sampled  at  three  other  sec-
tions, including Furkaska, Kamenná Poruba (both belong to
the Fatric Unit), and Trlenská Valley (Tatric Unit) (Fig. 1).

(1) The Skladaná Skala quarry is situated in the northern-

most part of the Ve ká Fatra Mountains (49°7

’15.66” N;

19°13

’27.98” E, Fig. 2). Rakús (1963, 1984) showed that

this section exposes about 400 meters of the Janovky Forma-
tion and consists of a succession of moderately- to highly-bio-
turbated marls, marlstones, and mudstones, with intercalations
of  infrequent  crinoidal  calcarenites  and  spongiolithic  lime-
stones. The lower, about 70 m-thick interval is represented by
marly limestones with thin marly interlayers and contains the
Upper  Sinemurian  ammonites  Echioceras  raricostatum  and
Oxynoticeras  oxynotum.  The  middle,  about  225 m-thick  in-
terval  is  formed  by  alternation  of  equally-thick  marly  lime-
stones and marls, with some spiculitic and sandy limestones,
and ammonites of Pliensbachian age (Amaltheus stokesi and
Pleuroceras  spinatum).  The  uppermost,  about  105 m-thick
interval  (Lower-Middle  Toarcian)  is  dominated  by  marls.
This interval contains the ammonites Dactylioceras cf. semi-
celatum,  D.  atheticum,  Harpoceras  ex  gr.  falciferum,  and
Hildoceras  ex  gr.  bifrons.  Rare  remains  of  rhynchonelli-
formean  brachiopods  are  represented  by  calcitic  shells,  bi-
valves  and  ammonites  are  preserved  as  moulds.  Here,  we

357

TRACE-FOSSIL ASSEMBLAGES IN “SPOTTED” (FLECKENMERGEL—FLECKENKALK) DEPOSITS

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

analyse an ~ 85 m-thick portion of the succession that pre-
dominantly captures the Upper Pliensbachian, with a few
samples also capturing the lowermost Toarcian.

(2) Furkaska is located in the Western Tatra Mts in a

creek ravine on the western side of the Furkaska peak
(49°15

’33.54” N; 19°47’6.02” E). The Janovky Formation

Fig. 1. Locality map. F – Furkaska, S – Skladaná Skala Quarry, TD – Trlenská
Valley, KP – Kamenná Poruba. The lower plot S displays the location of
Skladaná Skala section (black arrow). The dashed line refers to a railway line,
bolts of lightning represent electricity networks.

Fig. 2. An arrow shows a simplified geological map
showing (arrow) the location of the Skladaná Skala sec-
tion (after Gross et al. 1994, modified).

in this section is represented by the basal, 20 m-thick spotted
marls, and the upper, about 60 m-thick spotted marly lime-
stones that alternate with marls (Gaździcki et al. 1979).

(3) Trlenská Valley (49°2

’26.37” N; 19°15’1.37” E) is

located in the northern parts of the Ve ká Fatra Mts. Poorly
exposed natural outcrops consist of marly limestones of the

Janovky Formation in the strata overlying the
crinoidal limestones of the Trlenská Formation
(Mišík & Rakús 1964).

(4) Kamenná Poruba is situated in Malá

Fatra Mts. Samples with marly limestones of
the Janovky Formation were collected in a
poorly exposed ravine at Porubský potok Creek
(49°4

’2.35” N; 18°41’29.99” E).

Methods

Trace fossils were documented on photo-

graphs of cross-sections of ~ 200 polished slabs
and  in  bed-by-bed  observations  in  the  field
(Fig. 3). The new ichnogenus and ichnospecies
Lamellaeichnus  imbricatus  described  in  the
systematic part is represented by 363 specimens
from  Skladaná  Skala,  two  specimens  from  the
Trlenská  Valley,  24  specimens  from  Kamenná
Poruba,  and  13  specimens  from  Furkaska.  The
morphology  of  trace  fossils  was  studied  in
cross-  and  in  longitudinal  sections.  Longitudi-
nal  sections  were  cut  either  vertically  or  hori-
zontally  (relative  to  burrow  orientation).  Two
slabs were serially cross-sectioned for three-di-
mensional  morphological  study  of  Lamellae-
ichnus  (Fig. 5).  Distances  between  sections
ranged  between  0.2  to  1 mm.  The  trace  fossil
fill and the composition of the surrounding ma-
trix were detected in thin-sections.

Morphological study and statistical analyses

of six morphological parameters (Fig. 4) were

360

ŠIMO and TOMAŠOVÝCH

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

performed  on  103  cross-sectioned  specimens  of  Lamellae-
ichnus from Skladaná Skala (1 – lamella width, 2 – total
height, 3 – burrow width, 4 – burrow height, 5 – thick-
ness  of  lamella,  6  –  height  of  lamella  arch).  Although  the
morphology  of  lamellae  and  basal  burrow  are  affected  to
some degree by compaction, the parameters were measured
on cross-sections that were constructed perpendicularly rela-
tive  to  the  burrow  orientation.  We  analysed  size-frequency
distributions  of  these  parameters,  and  tested  whether  the
cross-sectional shape of the new trace fossil changes isomet-
rically  or  allometrically  with  increasing  size,  using  reduced
major axis (RMA) regressions.

The cluster analysis and non-metric multidimensional

scaling (NMDS) based on presence—absence data of 9 ichno-
genera and the agglutinated foraminifer Bathysiphon in 55

beds  were  performed  to  detect  variation  in  trace-fossil  as-
semblage  composition.  We  used  Sorenson  dissimilarity  as
a basis  for  quantifying  between-bed  relationships,  and
weighted  average  linkage  method  to  generate  clusters.  We
used Mantel test to evaluate whether there are any temporal
changes in the composition of trace-fossil assemblages.

The holotype (numbered Z36999a) and several tens of ad-

ditional  specimens  of  Lamellaeichnus  imbricatus  from
Skladaná  Skala  (numbered  samples  Z36999b,c;  Z36995,
Z36996,  Z36997,  Z36998,  Z37000),  Trlenská  Valley
(Z37750, Z37751), Kamenná Poruba (Z37748), and Furkaska
(Z37749)  are  deposited  in  the  Slovak  National  Museum  in
Bratislava.  Whole  polished  slabs  (196  samples)  were  also
scanned, numbered (No. Z37752) and deposited in the Slovak
National Museum.

Fig. 6. A – Lamellaeichnus (L) vertical sections, a specimen in the inset was designated as holotype (numbered Z36999a). Chondrites cf.
intricatus (Ci) and Palaeophycus (Pa) occupied burrows of older generation (probably Thalassinoides – white arrow). Teichichnus (Te),
Zoophycos (Z) are formed by crescent-shaped spreite structure. Planolites (P) is represented by unwalled, simple, dark burrows. B – Thin-
section (cut perpendicularly to bedding) view shows a dark bioclastic infill of Lamellaeichnus (L), light-coloured walls of Bathysiphon
tests are silicified, hair-like Trichichnus (T) is filled with pyrite. Scale bar is 5 mm. C – Vertical section shows Lamellaeichnus (L),
Rhizocorallium (R), Bathysiphon (B), Chondrites cf. intricatus (Ci) and Planolites (P). Skladaná Skala.

361

TRACE-FOSSIL ASSEMBLAGES IN “SPOTTED” (FLECKENMERGEL—FLECKENKALK) DEPOSITS

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

Total organic carbon (TOC) was measured in 4 samples of

dark  grey  sediment  fills  of  Lamellaeichnus,  4  samples  of
mottled, brownish sediments with relicts of Lamellaeichnus,
and  4  samples  of  structureless,  light  grey  sediments  with  a
Ströhlein C-MAT 5500 automatic infrared detector. Approx-
imately  0.05 g  of  sample  (pulverized  and  dried  at  110 °C)
was burned down in the oxygen atmosphere at the tempera-
ture  range  50—1000 °C.  The  CO

produced during combus-

tion was detected by the C-MAT 5500 infrared detector and
converted to total carbon content. Another split of sample was
treated with hot HCl in order to dissolve carbonates. The in-
soluble residue was analysed to obtain the percentage of TOC.

Systematic ichnology

Lamellaeichnus new ichnogenus

D e r i v a t i o n o f n a m e : Derived from “lamellae” that

correspond to crescent-shaped packets of backfilled sedi-
ment and from Greek ichnos – trace.

T y p e i c h n o s p e c i e s : Lamellaeichnus imbricatus.
D i a g n o s i s : Structure composed of inclined lamellae that

protrude at an acute angle from horizontal basal cylinder.

Lamellaeichnus imbricatus new ichnospecies

(Figs. 4, 5, 6, 7, 8, 9, 11, 12)

D i a g n o s i s : As for the ichnogenus.
D e r i v a t i o n o f n a m e : Derived from “imbrication” –

imbricately-arranged lamellae.

H o l o t y p e : The holotype (Z36999a) is preserved with

two other specimens (Fig. 6A) that were assigned to
paratypes (Z36999b,c). They are deposited at the Slovak Na-
tional Museum in Bratislava.

C o m p a r a t i v e m a t e r i a l : Skladaná Skala: Specimen

Z36996  preserved  on  the  bedding  plane  is  also  assigned  to
the  paratype  material.  The  polished  slab  Z36997  with  18
Lamellaeichnus  cross-sections  is  supplemented  by  illustra-
tions of 14 sections (Z37752). Sample Z37000 contains seven
Lamellaeichnus  cross-sections.  The  sample  with  longitudi-
nal  horizontal  Lamellaeichnus  section  corresponds  to
Z36998 (Fig. 7).

Kamenná Poruba: Three specimens from one sample

(Z37748a,b,c).

Furkaska: One sample cut perpendicularly relative to the

bedding plane with four specimens of Lamellaeichnus
(Z37749a,b,c).

Trlenská Valley: Two samples with two specimens

(Z37750, Z37751).

Additionally, 194 polished slabs with Lamellaeichnus

imbricatus and other trace fossils were photographed and
saved in JPG format on the compact disk with a number
(Z37752). All material is housed at the Slovak National Mu-
seum in Bratislava.

Fig. 7. Three-dimensional reconstruction of Lamellaeichnus with a cross-section and a horizontal longitudinal section. A – Reconstruction
of Lamellaeichnus with a cross-section. B – Idealized longitudinal horizontal section above the basal burrow oriented according to
Fig. 7A. C – The cross-section of the holotype (No. Z36999a), detail of Fig. 6A. A central part of the basal burrow is lighter and differs
from peripheral, darker part of fill. D – horizontal-section (No. Z36998). Scale bar: 10 mm. The arrows are pointing to expected directions
of producer movement. Skladaná Skala.

362

ŠIMO and TOMAŠOVÝCH

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

T y p e h o r i z o n a n d t y p e l o c a l i t y : Janovky Forma-

tion, Skladaná Skala Quarry.

D e s c r i p t i o n : Guttered, wedge-shaped lamellae have

convex-up  orientation  and  merge  with  the  basal  cylindrical
burrow at an acute angle. They are separated from each other
by surrounding sediment and gradually taper upward so that
they  produce  sharp,  thin-bladed  or  leaf-like  structures.  In
cross-sections, typically one lamella, or sporadically two or
three lamellae, appear as distinct convex-up crescents located
above  the  basal  tunnel-shaped  burrow.  These  crescents  are
typically  wider  at  their  base  relative  to  the  diameter  of  the
basal burrow. Circular or lenticular cross-sections of the basal
burrow locally consist of asymmetric concentric layers, with
their centroid being asymmetrically located at the bottom of
the burrow. These layers represent basal extensions of lamel-
lae  that  are  stacked  in  the  basal  burrow.  In  the  longitudinal
horizontal sections located above the basal burrow, lamellae
form a row of discrete, crescent-shaped structures. In the lon-
gitudinal  vertical  sections,  these  lamellae  are  arranged  in  a
row at an acute angle, and they merge with the basal cylinder

gradually. Secondary successive branching occurs, but true
branching is absent.

Cross-sectional shapes

The most frequent and the most diagnostic attribute of this

trace  fossil  is  visible  in  cross-sections:  dark-coloured,  con-
vex-up crescent sections of lamellae are located above an el-
liptical or rounded section of the basal burrow with the same
sediment  colour.  In  sporadic  cases,  one  cross-section  cap-
tures  two  or  three  crescent-shaped  lamellae  (Fig. 5).  Such
cross-sections of L. imbricatus are partly similar to Heimdallia
chatwini  of  Fillion  &  Pickerill  (1990:  plate 8,  fig. 8,  p. 99).
In the longitudinal horizontal sections located just above the
main  cylindrical  burrow,  lamellae  form  discrete  crescent-
shaped  structures  (Figs. 7,  8).  In  the  longitudinal  vertical
sections, lamellae extend upward from a horizontal tunnel at
an acute angle and gradually taper upward towards a pointed
and thin, blade-like protrusion. The basal burrow is represented
by  a  horizontal,  elongated  tunnel  with  rounded  or  elliptic

Fig. 8. Horizontal sections of Lamellaeichnus. A – Lamellaeichnus with well-preserved lamellae in a longitudinal section on a weathered
bedding plane. B – The detail of the best preserved lamellae. Preservation is considerably marked by compaction. C – Crescent shapes
arranged in rows are similar to Taenidium and horizontal sections that cross basal burrows of Lamellaeichnus are similar to Planolites or
Thalassinoides. Skladaná Skala.

363

TRACE-FOSSIL ASSEMBLAGES IN “SPOTTED” (FLECKENMERGEL—FLECKENKALK) DEPOSITS

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

cross-section, 2—19 mm in horizontal diameter, and 1—19 mm
in vertical diameter. The width of lamellae attains 4—28 mm
in cross-sections. The lamellae close to the point of merging
with the basal cylindrical tunnel attain the largest width and
thickness. The height of lamellae in cross-sections is be-
tween 2—30 mm. The length of the whole burrow likely ex-
ceeds several tens of centimeters.

Burrow orientation

The trace fossil is predominantly horizontal, slightly waved

horizontally and vertically.

Branching

Secondary successive branching (Bromley 1996) was ob-

served in horizontally-sectioned specimens (Fig. 8B).

The trace fossil filling

The fill of the lower cylindrical burrow and the wedge-

shaped lamellae is formed by identical, fine-grained sedimen-
tary material, which is much darker relative to the light grey
colour of the surrounding matrix, although the sediment grain
size is identical. Sponge spicules in the filling are evidently re-
arranged by bioturbation. The boundary between matrix and
the fill is sharp, although the trace fossil is without a wall. The

fill  of  the  basal  burrow  can  locally  display  very  thin,  verti-
cally-stacked basal parts of lamellae (Fig. 9). Boundaries be-
tween  distinct,  convex-up  crescent-shaped  sections  are
sporadically  visible  within  the  upper  part  of  cylindrical  bur-
rows (Fig. 7), and become less visible in their central parts.

Shape and its dependency on size

The height and width of Lamellaeichnus change isometri-

cally with respect to each other because the allometric coeffi-
cients are not significantly different from one (Fig. 10). In
other words, the burrow width and burrow height increase at
the same rate as lamella width, and total height also increases
at the same rate as lamella width. This isometry can imply that
the producer also grew isometrically during the ontogeny.
Size-frequency distributions are right-skewed (Fig. 10), show-
ing that most burrows have a small diameter of the basal bur-
row ( < 6 mm). The total height of some burrows attains 30 mm.

P r e s e r v a t i o n : Endogenic full reliefs within bioturbated

sediments, observed in vertical longitudinal and horizontal
cross-sections, are most frequent. Specimens with secondary
successive branching are sporadically visible on bedding
planes.

R e m a r k s : The lamellae of Lamellaeichnus imbricatus

extend upward and form wedge-shaped structures and coa-
lesce with a tube-shaped burrow at the base. The lower cylin-
drical burrow can be branched (secondary successive

Fig. 9. The sketches illustrate the arrangement of lamellae and their coalescence within the basal burrow of Lamellaeichnus. A – Lamellae
(on the cross-sectional view) are colour-differentiated. Each lamella has one number. B – The most typical Lamellaeichnus cross-section
(Kamenná Poruba locality). An arrow shows downward direction of the trace maker’s movement. C – A hypothesized construction of Lamel-
laeichnus. Black part represents a hypothetical producer. The grey field shows fodinichnial substrate reworked into the inclined lamellae.
Arrows show direction of the producer’s movement. The third figure from above illustrates downward movement of anterior part of the
producer. The third figure is captured by the cross-section in Fig. 9B.

364

ŠIMO and TOMAŠOVÝCH

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

branching only) and thus can be confused with Planolites or
Thalassinoides. In addition, the parallel crescent sections lo-
cated  above  the  basal  burrow  running  through  the  wedge-
shaped lamellae can resemble a row of menisci without wall,
and  these  can  be  confused  with  Taenidium.  Two  or  three
concave  crescent-shaped  lamellae  that  are  sporadically
present  in  cross-sections  of  L.  imbricatus  (Figs. 5,  11A,B)
are similar to a protrusive teichichnid trace fossil (Seilacher
1990, 2007). Although the cross-sections of Teichichnus are
generally  retrusive  (Buckman  1996;  Seilacher  2007),  some
minor  proportion  of  teichichnid  structures  is  protrusive.  In-
deed,  Teichichnus  from  Skladaná  Skala  is  predominantly
characterized by protrusive cross-sections. Cross-sections of
Teichichnus from Skladaná Skala display a chain of protru-
sive  meniscate  structures  terminated  by  oval  basal  burrow.
Protrusive  Teichichnus  cross-sections  thus  strongly  differ
from protrusive L. imbricatus, consisting of one to maximally
three crescent-shaped sections situated above the basal burrow
and separated from each other by the surrounding matrix.

The lamellar structure of L. imbricatus can be compared

with trace fossils that have a heterogeneous type of backfill
such as Taenidium and do not possess any wall. The striking
feature of L. imbricatus is represented by long and asymmet-
rically prolonged lamellae (menisci in sections) of reworked

sediment. Irregular, deeply asymmetric menisci in the back-
fill are typical of Taenidium crassum (Bromley et al. 1999)
and deeply arcuate menisci are typical of Taenidium camero-
nensis (Brady 1947). Taenidium Heer, 1877 is defined as an
unlined or very thinly lined, unbranched, straight or sinuous
cylindrical trace fossil containing a segmented fill articulated
by meniscus-shaped partings (D’Alessandro & Bromley
1987). However, all menisci in Taenidium are present within
the cylindrical burrow, whereas menisci in L. imbricatus
protrude above the basal burrow.

The morphology of L. imbricatus is also comparable to

trace  fossils  that  possess  vertical  or  inclined  spreite  struc-
tures,  abruptly  passing  into  a  horizontal  basal  burrow.  This
description  complies  with  the  description  of  trace  fossils
Heimdallia  Bradshaw,  1981  and  Dictyodora  Weiss,  1884.
Cross-sections of Heimdallia (illustrated in Buckman 1996)
and  Dictyodora  (illustrated  in  Benton  &  Trewin  1980)  are
characterized  by  basal  burrows  with  reworked  sediment  of
spreite  structure  located  above  them.  Spreite  structures  of
these trace fossils differ from the fill of Lamellaeichnus basal
burrows,  and  spreite  concave  lamellae  are  densely  packed
(Buckman 1996: fig. 2). In contrast, lamellae of L. imbricatus
are separated by the surrounding matrix and are arranged in
sparser rows than those of Heimdallia.

Fig. 10. Bivariate relationships with allometric coefficients for three pairs of morphological dimensions imply that the trace grew isometri-
cally with increasing size (top row). The relations among other dimensions also show isometric growth (not shown). Frequency distribu-
tions of three morphological dimensions are right-skewed and show that the total burrow height, including the basal burrow and lamellae,
ranges up to 30 mm (bottom row). LCI and UCI correspond to lower and upper 95% confidence intervals.

366

ŠIMO and TOMAŠOVÝCH

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

Ethological and burrow construction model

Meniscate, crescent-shaped spreite structures are generally

considered as backfill structures in trace fossils (e.g. Bromley
&  Asgaard  1979;  D’Alessandro  &  Bromley  1987;  Bromley
1996;  Seilacher  2007).  Lamellaeichnus  is  also  clearly
formed  by  backfills  because  crescent-shaped  meniscate
structures  are  stacked  in  the  main  basal  burrow  and  the
lamellae  represent  their  extensions.  The  oblique  orientation
of these crescent-shaped structures (in longitudinal sections,
Figs. 7B, 8, 9) implies that the producer was moving in two
directions. First, it pushed the processed sediment backwards
and upwards, with the anterior part moving slantwise-up and
the posterior part remaining in the main burrow. Second, the
producer returned back to the original horizontal orientation
and  progressed  forward.  Lamellaeichnus  thus  represents  a
horizontal  structure  left  by  a  deposit-feeder  (fodinichnion),
which consists of relatively large extended backfilled packets
of  reworked  sediment.  The  Lamellaeichnus  tracemaker  was
thus imbricating its backfill under an acute angle relative to
the  direction  of  its  movement.  This  direction  and  the  mode
of  burrow  construction  is  comparable  to  H.  mullaghmori
(Buckman 1996: fig. 8).

Parataenidium consists of similarly inclined and extended

packets  of  reworked  sediment  arranged  within  horizontal
burrows (Margaritichnus reptilis was synonymized to Para-
taenidium moniliformis by Buckman in 2001). These packets
of  sediment  were  placed  downward  close  to  the  abdominal
part of the trace maker (Seilacher 2007: plate 17, Margarit-
ichnus  picture;  Buckman  2001:  figs. 2A,B,  9B).  The  trace-
maker of Parataenidium imbricated backfill under an obtuse
angle  relative  to  the  direction  of  its  movement.  The  same
mode  of  the  burrow  construction  also  applies  to  Para-
taenidium  seymourensis  Uchman  &  Gaździcki,  2006.  The
diagnostic  key  for  detecting  the  direction  of  locomotion  in
Parataenidium  and  Lamellaeichnus  is  thus  represented  by
orientation  of  crescent-shaped  structures  formed  by  re-
worked sediment.

Chondrites Sternberg, 1833

D i a g n o s i s : Regularly branching tunnel systems consist-

ing of a small number of mastershafts that are connected
with the surface and ramify at depth into a dendritic network
(Uchman 1999).

R e m a r k s : Chondrites is interpreted as a feeding system

produced by a deposit-feeder or by a chemosymbiontic or-
ganism (Fu 1991; Uchman 1999; Hertweck et al. 2007).

Larger form of Chondrites cf. C. targionii (Brogniart, 1828)

(Figs. 11, 12A)

D i a g n o s i s : Dendritic network with well expressed pri-

mary successive branching. The angle of branching is usually
acute (Uchman 1998).

M a t e r i a l : Several tens of specimens.
D e s c r i p t i o n : The large form of Chondrites with succes-

sive branching. Diameter of the shaft varies from 1.5 to
3 mm. Branching was only observed on sections parallel

with bedding planes. Angles of branching range from 40° to
48°. Sections perpendicular to bedding planes display clus-
ters of spots that belong to Chondrites.

Larger form of Chondrites cf. recurvus (Brogniart, 1823)

(Fig. 12B)

D i a g n o s i s : Lateral branches arising on one side of a mas-

terbranch only. All lateral branches on each masterbranch are
bent in the same direction, or lateral branches on one master-
branch can be bilaterally opposed relative to lateral branches
on an opposite masterbranch. One or two orders of branch-
ing, rarely a third (Fu 1991).

M a t e r i a l : Two specimens.
D e s c r i p t i o n : Specimens were preserved on a bedding

plane.  Tunnels  are  filled  with  dark  grey  micritic  sediment.
Diameter of the shafts varies from 2 to 4 mm. Second-order
branches  arise  from  the  convex  side  of  bowed  first-order
branch.  Third-order  branches  are  poorly  visible.  Length  of
first-order branch is 55 mm. Second-order branches are 16 to
30 mm long. Angles of branching are 31° to 38°.

Smaller form of Chondrites cf. intricatus (Brogniart, 1823)

(Figs. 6A,C, 11)

D i a g n o s i s : Small Chondrites consisting of numerous,

downward-radiating, mostly straight branches. The angle of
branching is usually less than 45°. The branches are less than
1.0 mm wide (mostly about 0.5 mm). The burrow system is
more than 20 mm wide (Fu 1991; Uchman 1999).

M a t e r i a l : Several tens of specimens.
D e s c r i p t i o n : Small form of Chondrites with down-

ward-  to  sideward-branching  tunnels.  Clusters  of  tiny  spots
on the vertical sections are situated mostly inside larger bur-
rows  (Thalassinoides,  Planolites).  Diameters  of  shafts  are
smaller than 1 mm (Figs. 6A, 11A, 12C). Angles of branching
vary from 24° to 35°. The sediment fill is darker than the sur-
rounding sediment. Aberrant forms situated within Planolites
and Thalassinoides  (referred  to  Bandchondriten  –  Fu  1991)
are relatively frequent.

Palaeophycus Hall, 1847

Palaeophycus heberti (Saporta, 1872) (Figs. 6A,C, 11A,C)

D i a g n o s i s : Branched, unbranched, smooth or ornamented,

typically lined, essentially cylindrical, predominantly hori-
zontal, oblique burrows of variable diameter, burrow fill
without any structure (Pemberton & Frey 1982).

M a t e r i a l : 25 samples with several tens of specimens.
D e s c r i p t i o n : Palaeophycus with a light-coloured wall-

lining and a darker internal burrow fill. Burrow diameter var-
ies from 3.5 to 7.8 mm. Pale wall lining is 0.4 to
1.8 mm-thick.

R e m a r k s : Palaeophycus is interpreted as an open burrow

of vagile, omnivorous or carnivorous polychaetes (Pemberton
& Frey 1982).

Planolites Nicholson, 1873

Planolites isp. (Figs. 6A, 8B, 11A,B,C)

368

ŠIMO and TOMAŠOVÝCH

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

D i a g n o s i s : Straight or irregularly waved, horizontal, cy-

lindrical trace fossil without bioglyphes and wall (Fillion &
Pickerill 1990).

M a t e r i a l : Several tens of specimens.
D e s c r i p t i o n : Cross-sections are elliptical, flattened by

compaction. Diameters of these burrows vary from 2 to 6 mm.
They can be misclassified with sections of large Chondrites.

R e m a r k s : Planolites is an eurybathic trace fossil inter-

preted as the work of a deposit feeder. Ichnotaxonomy of
Planolites and Palaeophycus was discussed by Pemberton &
Frey (1982).

Rhizocorallium Zenker, 1836
Rhizocorallium isp. (Fig. 6C)

D i a g n o s i s : U-shaped spreite burrows, parallel or ob-

lique to bedding plane; limbs more or less parallel and dis-
tinct; ratio of tube diameter to spreite width usually 1 : 5
(Fürsich 1974; Uchman 1998; Schlirf 2011).

Fig. 13. Cluster analysis of 55 samples on the basis of Sorenson dissimilarity (presence—absence data) and weighted average linkage method.
We separated the dendrogram into three assemblage groups.

M a t e r i a l : Two specimens.
D e s c r i p t i o n : Rhizocorallium was distinguished on the

basis of cross-sections that show concordant spreite (cres-
cent-shaped) structures and do not possess any wall. The
width of Rhizocorallium cross-sections is 53 mm.

R e m a r k s : Rhizocorallium is produced by deposit- and

suspension-feeders,  and  typically  occurs  in  shallow-water
environment of the upper offshore zone (Jaglarz & Uchman
2010). However, deep-water Rhizocorallium  with Zoophycos
occurs  in  the  Paleogene  flysch  of  the  Outer  Western  Car-
pathians (Uchman 1992).

Teichichnus Seilacher, 1955

Teichichnus cf. T. sigmoidalis Seilacher, 1955

(Figs. 6A, 11A, 12D,F)

D i a g n o s i s : Long, wall-shaped septate structures that

consist of a pile of gutter-shaped laminae (Fillion & Pickerill
1990; Seilacher 2007).

369

TRACE-FOSSIL ASSEMBLAGES IN “SPOTTED” (FLECKENMERGEL—FLECKENKALK) DEPOSITS

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

M a t e r i a l : Several tens of specimens.
D e s c r i p t i o n : Backfill of Teichichnus shows a down-

ward movement of its producer. This protrusive structure in-
dicates  that  it  belongs  to  T.  sigmoidalis  (according  to
Seilacher 2007: plate 41). Diameters of basal burrows range
from  2.5  to  5 mm.  The  width  of  the  spreite  chain  slightly
widens  towards  the  top  and  attains  diameters  from  3.5  to
6 mm.  The  height  of  the  spreite  chain  in  vertical  cross-sec-
tions varies between 5.5 to 19 mm.

R e m a r k s : Teichichnid forms have similar cross-sections

as other trace fossils (e.g. Rhizocorallium, Diplocraterion, or
Syringomorpha).

Thalassinoides Ehrenberg, 1944

Thalassinoides isp. (Figs. 6A, 12E)

D i a g n o s i s : Three-dimensional system of smooth-walled

burrows with variable shaft diameter. Shafts branch into Y- or
T-shaped burrows that are broader at bifurcation points
(Uchman 1998, 1999). The sediment fill of Thalassinoides is
not structured but the fill can be meniscate (Fürsich 1973;
Seilacher 2007).

M a t e r i a l : Two samples.
D e s c r i p t i o n : Truly branching burrows were assigned to

Thalassinoides. Several undetermined branching structures,
observed on bedding planes, can also belong to Thalassi-
noides. The burrow diameter varies between 3 and 15 mm.

R e m a r k s : Thalassinoides occurs in a broad range of

environments (e.g. Archer & Maples 1984; Ekdale &
Bromley 2003; Miller III. et al. 2004). Thalassinoides pro-
ducers are assigned mostly to crustaceans (e.g. Carvalho et
al. 2007).

Trichichnus Frey, 1970

D i a g n o s i s : Branched or unbranched, hair-like, cylindri-

cal, straight to sinuous trace fossils, oriented at various an-
gles (mostly vertical) with respect to the bedding. Burrow
wall distinct or indistinct, lined or unlined (Frey 1970; Fillion
& Pickerill 1990; Uchman 1999).

R e m a r k s : Uchman (1999) noted that the preservation of

Trichichnus  lining  was  affected  by  diagenetic  processes.
Three ichnospecies of Trichichnus were distinguished, includ-
ing T. linearis, T. simplex (Fillion & Pickerill, 1990) and T.
appendicus  (Uchman,  1999).  Trichichnus  occurs  in  shallow-
water (Fillion & Pickerill 1990) and deep-sea deposits (Wetzel
1981).  The  location  of  Trichichnus  in  deeper  tiers  together
with  Chondrites  can  imply  that  its  producers  –  meiofaunal
deposit-feeders or chemosymbionts – tolerated oxygen-de-
ficient conditions (Uchman 1995).

Trichichnus simplex Fillion & Pickerill, 1990

(Figs. 6B, 11A)

D i a g n o s i s : Unlined Trichichnus (Fillion & Pickerill, 1990).
M a t e r i a l : Several tens of specimens.
D e s c r i p t i o n : Trichichnus is one of the common trace

fossils in the Skladaná Skala section. The diameter of pre-
dominantly pyritic, inclined and vertical burrow attains

0.1—0.2 mm. Trichichnus with sporadic branching was ob-
served on polished slabs and in thin sections, and was also
detected by X-ray microtomography Quarry (Šimo 2012).

Zoophycos Massalongo, 1855

Zoophycos isp. (Fig. 6A)

D i a g n o s i s : Spreiten structures consisting of numerous

small,  more  or  less  U-  or  J-shaped  protrusive  burrows  of
variable  length  and  orientation.  Causative  U-  or  J-shaped
burrows  widen  downward  or  upward  to  a  helicoidal  spiral.
Spreiten are arranged in helicoid spirals with an overall cir-
cular, elliptical or lobate outline, a central vertical tunnel or
marginal  tube  may  be  present.  The  whole  helicoidal  struc-
ture  is  composed  of  protrusive  lamellae  that  can  extend  to
the lobe, marginal helicoidal parts could be lined by marginal
tube (modified according to Olivero 2003).

R e m a r k s : This structure was interpreted as a “streep

miner”  (Seilacher  1967),  later  it  was  explained  as  a  refuse
dump or garden (Bromley 1991). The producer of this struc-
ture  can  be  attributed  to  sipunculoids  (Wetzel  &  Werner
1981),  polychaete  annelids,  arthropods  (Uchman  1998  and
references therein) and echiuran “worms” (Kotake 1989).

M a t e r i a l : Three samples.
D e s c r i p t i o n : Rare trace fossil, spreite lamellae of Zoo-

phycos occur sporadically on bedding planes. Parallel menis-
cate lines are visible in cross-sections. The width of the
spreite spiral attains 1.5—2.5 mm.

Variation in composition of trace-fossil

assemblages

The diversity of trace-fossil assemblages with nine ichno-

genera  in  the  Skladaná  Skala  section  is  generally  larger  than
previously reported from other Lower Jurassic spotted depos-
its. They are comparable to the assemblage with  Chondrites,
Paleophycus, Phycosiphon, Planolites, Taenidium, Teichich-
nus,  Thalassinoides,  Trichichnus,  and  Zoophycos  from  the
Lejowa  Valley  in  the  High  Tatra  Mountains  (Uchman  &
Myczyński 2006). For example, Jacobshagen (1965) reported
Phymatoderma  and  Zoophycos  from  the  Allgäu  Formation
(Eastern  Alps)  and  Wieczorek  (1995)  reported  Zoophycos,
Chondrites,  Helminthoida,  ?Taenidium,  ?Teichichnus  and
U-shaped  trace  fossils  from  the  Janovky  Formation  (High
Tatra Mountains). On the basis of presence—absence data of
9 ichnogenera and the agglutinated foraminifer Bathysiphon,
55 samples from the Skladaná Skala section do not markedly
differentiate in an ordination space (NMDS) into distinct as-
semblage groups. The median number of ichnogenera per bed
is 3. All samples contain small-sized Chondrites and primarily
differ in the presence of three ichnotaxa produced by deposit-
feeders and one deposit-feeding foraminifer (Lamellaeichnus,
Chondrites cf. targionii, Teichichnus and Bathysiphon).

The cluster analysis delimited three assemblage groups

(Fig. 13). However, these groups overlap in NMDS (Fig. 14)
and the different linkage methods produce different clusters,
demonstrating that the grouping of beds into the three as-
semblage groups does not correspond to distinct community

370

ŠIMO and TOMAŠOVÝCH

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

groups. The average Jaccard dissimilarity among all samples
is  0.52,  implying  that  the  probability  of  drawing  the  same
ichnotaxon from two randomly-selected beds is about 50 %.
The  relationship  between  Sorenson  dissimilarity  and  the
stratigraphic distance among samples is very low (Mantel-test
Pearson  correlation = 0.11,  p = 0.054),  showing  no  clear  tem-
poral  change  in  trace-fossil  composition  up-section.  There-
fore, trace-fossil assemblages in the Pliensbachian part of the
succession correspond to one basic community type with om-
nipresent  Chondrites  cf.  intricatus,  which  is  associated  with
taxa with moderate occupancy (i.e. proportion of beds with at
least  one  occurrence),  including  Lamellaeichnus  (0.78 %),
Teichichnus  (0.51 %),  Chondrites  cf.  targionii  (0.4 %),
Palaeophycus  (0.31 %),  and  Bathysiphon  (0.2 %).  However,
fine-scale stratigraphic analyses of changes in size and numeri-
cal abundance of trace fossils will be needed to reveal whether
high-frequency fluctuations can be detected up-section.

Ichnofabric and tiering patterns

Trichichnus crosses Chondrites and all other trace fossils,

Chondrites  crosses  Lamellaeichnus,  and  Palaeophycus  fre-
quently  penetrates  through  Lamellaeichnus.  These  relations
imply  separation  of  the  transitional  layer  into  two  or  three
tiers,  although  the  ichnofabric  clearly  shows  an  unbroken
overprinting of successive colonization events under contin-
uous  sediment  aggradation,  generating  complex  tiering  pat-
terns (Taylor et al. 2003). The deepest tier is thus represented
by  Trichichnus  simplex,  the  deep  to  intermediate  tier  by
Chondrites,  and  the  shallow  tier  by  mobile  deposit-feeders
represented by Lamellaeichnus imbricatus and Palaeophycus
(and less frequent Planolites). This tiering pattern and cross-
cutting relations are similar to those in the spotted facies in

the Lower Toarcian Fuente de la Vidriera section in the Betic
Cordillera  (Rodríguez-Tovar  &  Uchman  2010)  and  in
Cenomanian-Turonian  hemipelagic  sediments  in  the  Polish
Carpathians (Uchman et al. 2013). The presence of wall-lined
Palaeophycus points to softground conditions, but the bound-
aries  between  shallow-tier  burrows  of  Lamellaeichnus  and
sediment are sharp, implying a relatively stiff sediment con-
sistency in the upper tiers (Wetzel & Uchman 1998).

The lithological difference between burrows and the sur-

rounding  sediment  is  primarily  caused  by  differences  in  the
organic matter content. This difference generates the diagnos-
tic spotted appearance of “Fleckenmergel” and “Fleckenkalk”
deposits.  The  dark  organic-rich  infill  of  Lamellaeichnus
(mean TOC = 0.23 %, maximum TOC = 0.36 %) contrasts with
the  light  grey,  structureless  surrounding  sediment  (mean
TOC = 0.15 %,  maximum  TOC = 0.21 %).  Organic  matter  en-
richment in burrow fills of shallow-tier trace fossils such as
Lamellaeichnus  and  Palaeophycus  cannot  be  simply  ex-
plained  by  the  lack  of  oxygen  in  deeper  portions  of  transi-
tional layers where organic matter reactivity is reduced (Aller
2004). Such enrichment rather shows that the organic matter
(e.g. generated by decay, mucus secretion, buildup of metabo-
lites, or by chemoautotrophic bacterial production) even in the
shallow tiers of the transitional layer was not completely de-
composed,  oxidized,  or  consumed  by  subsurface  deposit-
feeders (Aller 1982). However, the relictual, less well-defined
mottled  traces  of  Lamellaeichnus  of  yellowish  or  light  grey
colour  (mean = 0.16 %,  maximum = 0.22 %  –  Fig. 15)  have
similar TOC levels as in structureless and homogenized sedi-
ment without any mottled structure. The preservation of these
relictual, organic-poor traces thus shows that Lamellaeichnus
was  temporarily  subjected  to  higher  redox  cycling  above  the
redox  potential  discontinuity  (RPD)  layer.  In  summary,  the

Fig. 15. Dark grey, well-delimited burrows of Lamellaeichnus have
higher  percentage  of  TOC  (mean  TOC = 0.23 %,  maximum
TOC = 0.36 %) than yellowish or light grey, relictual, mottled traces
of  Lamellaeichnus  (mean = 0.16 %,  maximum = 0.22 %)  and  than
light grey, structureless surrounding sediment (mean TOC = 0.15 %,
maximum  TOC = 0.21 %).  Boxplots  show  median  values,  25

and

quantiles and extreme values.

Fig. 14. Non-metric multidimensional scaling of 55 beds, based on
Sorenson  dissimilarity.  The  convex  hulls  delimit  the  presence  of
four  common  genera  (small-sized  Chondrites  occurs  in  all  sam-
ples).  The  three  circle  symbols  of  different  colour  correspond  to
three groups delimited by the cluster analysis.

371

TRACE-FOSSIL ASSEMBLAGES IN “SPOTTED” (FLECKENMERGEL—FLECKENKALK) DEPOSITS

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

ichnofabric  pattern  represented  by  abundant  organic-rich
shallow-tier burrows persisting for several tens of meters of
deposits at Skladaná Skala implies that the uppermost layers
of  the  sediment  column  close  to  the  sediment—water  inter-
face  were  frequently  subjected  to  poor  redox  cycling.  This
persistence  seems  to  primarily  reflect  long-term  recurrence
of oxygen-deficient bottom-water conditions that did not al-
low stronger redox cycling and inhibited long-term develop-
ment of a thicker mixed-layer. The agglutinated foraminifer
Bathysiphon  was  probably  an  inhabitant  of  the  uppermost
parts  of  the  mixed-layer  because  (1)  its  tubes  do  not  cross
trace fossils, (2) tube sediment infill does not differ from the
light  grey  surrounding  sediment,  and  (3)  recent  species  of
Bathysiphon  are  semi-infaunal  deposit-feeders  protruding
above the surface or located closely below the sediment—wa-
ter interface (Gooday et al. 1992, 2002).

Oxygen-limited benthic communities

A poor redox cycling in the uppermost parts of the sediment

column,  associated  with  the  reduced  thickness  of  the  mixed-
layer  in  present-day  soft-bottom  environments,  is  typically
associated  with  reduced  bottom-water  oxygen  concentrations
(Savrda & Bottjer 1991; Smith et al. 2000). The role of oxy-
gen-limitation  in  determining  the  structure  of  benthic  com-
munities  of  the  Janovky  Formation  is  further  supported  by
(1) dominance of trace-fossils produced by infaunal deposit-
feeders rather than by infaunal suspension-feeders (Ekdale &
Mason 1988; Lavaleye et al. 2002), (2) high abundance of tubes
of  the  hypoxia-tolerant  agglutinated  foraminifer  Bathysiphon
(Gooday et al. 2000, 2002), and (3) high abundance and occu-
pancy of Chondrites with  ~ 0.5 mm-sized branches (Bromley
& Ekdale 1984; Savrda & Bottjer 1986; Wetzel 1991; Parisi et
al. 1996; Martin 2004), all pointing to low oxygen concentra-
tions  in  bottom  and  interstitial  waters.  We  suggest  that  the
spotted  character  of  deposits,  with  dark  organic-rich  fills  in
burrows  of  shallow-tier  organisms  separated  from  a  lighter
surrounding  matrix,  generally  imply  a  shallow  location  of
RPD in the sediment because organic matter recycling and de-
composition in the transitional layer were not effective enough
during their deposition. With some exceptions (Thompson et
al. 1985), oxygen-deficient conditions ( < 0.3—0.5 ml/l O

) not

only increase mortality rates (Riedel et al. 2012) but also sig-
nificantly  reduce  energetically-costly  calcification  rates  and
can shift the community structure towards the dominance of
soft-bodied  fauna  (Rhoads  &  Morse  1971;  Rhoads  et  al.
1991; Levin et al. 2000). Hypoxia can thus explain the rarity
of  carbonate-producing  benthic  macroinvertebrates  in  the
Lower  Jurassic  spotted  deposits,  rather  than  limitation  by
soupy substrate or low food supply that can also reduce pro-
ductivity  of  heterotrophic  benthic  macroinvertebrates.  We
note  that  the  presence  of  belemnites  and  ammonites  –  i.e.
taphonomic control groups for calcitic and aragonitic macro-
invertebrates – implies that the rarity of benthic carbonate-
producing  macroinvertebrates  in  the  Janovky  Formation  is
not related to their low preservation potential.

The host rock at Skladaná Skala contains minute sponge

spicules that are either dispersed in sediment or densely-

packed in tube-walls of Bathysiphon, documenting the pres-
ence  of  epifaunal  components  in  the  community  structure.
These  spicules  either  represent  relicts  of  poorly-developed
sponge  communities  or  they  were  transported  from  sponge
communities  in  the  northern  parts  of  the  Zliechov  Basin
where  spiculite-rich  packstones  are  more  widespread  and  re-
current  than  at  the  Skladaná  Skala  section.  Such  packstones,
locally with in situ sponges (Jach 2002), signify the presence
of sponge-dominated meadows on the foot and slopes of topo-
graphic  elevations  (Jach  2002,  2005)  that  were  rimming  the
depocenters  with  spotted  deposits.  Therefore,  the  deposition
of Pliensbachian bioturbated deposits at Skladaná Skala partly
coincides with the deposition of spiculites in shallower, more
proximal, northern parts of the Zliechov Basin, now preserved
in the northern parts of the Malá Fatra and High Tatra Moun-
tains.  For  example,  spiculite-rich  packstones  (1)  underlie  the
spotted deposits of the Toarcian age in the Malá Fatra Moun-
tains,  (2)  alternate  with  “spotted”  marlstones  and  limestones
of  the  Janovky  Formation  in  the  Western  Tatra  Mountains,
and  (3)  overlie  the  spotted  deposits  of  the  Sinemurian—Early
Pliensbachian age in the Polish part of the High Tatra Moun-
tains (Lefeld et al. 1985). In the Skladaná Skala section, sev-
eral  isolated  spiculitic  limestone  beds  thus  probably
represent temporary and relatively short-term sponge coloni-
zation events of deeper habitats.

Restricted circulation and high sedimentation rates

The development of oxygen-deficient bottom-water condi-

tions is probably related to a combined effect of restricted cir-
culation  (promoting  stratified  water  columns)  and  high
sedimentation  rates  that  characterized  Early  Jurassic  depo-
centers of the Zliechov Basin. First, spotted deposits are con-
sistently reduced in the thickness across less than 20 km from
several  hundreds  of  meters  (Skladaná  Skala  section)  up  to  a
few meters (e.g. at Borišov and Horná Turecká sections in the
Ve ká Fatra Mountains  – Mišík & Rakús 1964) in southern
locations of the Zliechov Basin (central and southern parts of
the  Ve ká  Fatra  Mountains).  Second,  spotted  deposits  in  the
northern  parts  of  the  Ve ká  Fatra  Mountains  are  horizontally
and  stratigraphically  replaced  by  nodular  limestones  of  the
Adnet Formation in the southward direction (Mišík & Rakús
1964).  Third,  frequent  spiculitic  and  crinoidal  beds  imply
proximity  of  slope,  and  thus  more  northward  limit  of  the
depocenter  of  the  Zliechov  Basin,  in  the  eastern  part  of  the
High Tatra Mountains (Lefeld et al. 1985; Jach 2005). There-
fore, the thickness reduction by two orders of magnitude and
the  spatial  replacement  of  deep-water  “spotted”  facies  by
sponge meadows, by shallower sediments exposed to stronger
current action (crinoidal facies), and by highly condensed and
bioturbated sediments (nodular facies) imply topographic dif-
ferentiation of the Zliechov Basin into plateaus and semi-en-
closed,  sediment-catching  and  high-subsidence  depocenters.
Topographic  barriers  can  significantly  restrict  circulation,
while high sedimentation rates can be expected to reduce or-
ganic-matter  decomposition  and  redox  cycling,  favouring
oxygen-deficient bottom-water conditions. Such spatial vari-
ation  in  the  thickness  of  different  sediment  types  thus  indi-

372

ŠIMO and TOMAŠOVÝCH

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

cates both (1) higher sedimentation rates in areas with the de-
position of spotted facies, and (2) the presence of a deeper
trough in the Zliechov Basin, now preserved in the northern-
most parts of the Ve ká Fatra Mountains.

This scenario is analogous to the scenario developed for

the Middle Jurassic spotted deposits in the Pieniny Klippen by
Tyszka (1994a). We suggest that recurrent hypoxic conditions
seem to be the main cause of the rarity of macrobenthic car-
bonate  skeletal  invertebrates  in  spotted  deposits,  effectively
prevailing over significant temporal durations almost during
the whole Early Jurassic in depocenters of the Zliechov Ba-
sin. This interpretation does not imply that all spotted depos-
its of the Janovky (or Sołtysia Marlstone) Formation in more
marginal parts of the Zliechov Basin reflect hypoxic condi-
tions. The oxygen concentrations were probably less limiting
towards the southern and northern  parts  of  the  Zliechov  Ba-
sin, as implied by increasing abundance of spiculite-rich de-
posits  and  carbonate  producers  in  both  northward  and
southward directions.

Acknowledgments: We thank Jozef Michalík, Francisco J.
Rodríguez-Tovar,  and  Alfred  Uchman  for  helpful  com-
ments.  We  also  thank  Andreas  Wetzel  for  the  access  to  pa-
pers.  This  work  was  supported  by  the  Slovak  Research  and
Development  Agency  (LPP  0107-07  and  APVV  0644-10)
and by the Scientific Grant Agency (VEGA 2/0100/11 and
VEGA 0068/11).

References

Aller R.C. 1982: The effects of macrobenthos on chemical proper-

ties of marine sediment and overlying water. In: McCall P.L.
& Tevesz M.J.S. (Eds.): Animal-sediment relations. Plenum
Press, New York, 53—102.

Archer A.W. & Maples C.G. 1984: Trace-fossil distribution across

a marine-to-nonmarine gradient in the Pennsylvanian of south-
western Indiana. J. Paleontology 58, 2, 448—466.

Aubrecht R., Halouzka R., Kováč M., Krejčí O., Kronome B., Nagy-

marosy A., Plašienka D., Přichystal A. & Wagreich M. (Kováč
M. & Plašienka D., Eds.) 2002: Geological structure of the Al-
pine-Carpathian-Pannonian junction and neighbouring slopes of
the Bohemian Massif. Comenius University, Bratislava, 1—84.

Barras C.G. & Twitchett R.J. 2007: Response of the marine infauna to

Triassic-Jurassic environmental change: ichnological data from
southern England. Palaeogeogr. Palaeoclimatol. Palaeoecol.
244, 223—241.

Benton M.J. & Trewin N.H. 1980: Dictyodora from the Silurian of

Peeblesshire, Scotland. Palaeontology 23, 3, 501—513.

Bernoulli D. & Jenkyns H.C. 1974: Alpine, Mediterranean and Cen-

tral Atlantic Mesozoic facies in relation to the early evolution
of the Tethys. In: Dott R.H. & Shaver R.H. (Eds.): Modern and
ancient geosynclinal sedimentation: a symposium. Soc. Econ.
Paleont. Miner., Spec. Publ. 19, 129—160.

Böhm F., Dommergues J.-L. & Meister C. 1995: Breccias of the

Adnet Formation: indicators of Mid-Liassic tectonic event in
the Northern Calcareous Alps (Salzburg/Austria). Geol. Rdsch.
84, 272—286.

Böhm F. 2003: Lithostratigraphy of the Adnet Group (Lower to

Middle Jurassic, Salzburg, Austria) In: Piller W.E. (Ed.): Strati-
graphia Austriaca. Österr. Akad. Wiss., Schriftenr. Erdwiss.
Komm. 16, 231—268.

Bradshaw M.A. 1981: Paleoenvironmental interpretations and sys-

tematics of Devonian trace fossils from the Taylor Group (lower
Beacon Supergroup), Antarctica. N.Z. J. Geol. Geophys. 24, 5-6,
615—652.

Brady L.F. 1947: Invertebrate tracks from the Coconino Sandstone

of Northern Arizona. J. Paleontology 21, 5, 466—472.

Bromley R.G. 1991: Zoophycos: strip mine, refuse dump, cache or

sewage farm? Lethaia 24, 460—462.

Bromley R.G. 1996: Trace fossils, biology, taphonomy and applica-

tions. Second edition. Chapman & Hall, 1—361.

Bromley R.G. & Asgaard U. 1979: Triassic freshwater ichno-

coenoses from Carlsberg fjord, East Greenland. Palaeogeogr.
Palaeoclimatol. Palaeoecol. 28, 39—80.

Bromley R.G. & Ekdale A.A. 1984: Chondrites: a trace fossil indi-

cator of anoxia in sediments. Science 224, 872—874.

Bromley R.G., Ekdale A.A. & Richter B. 1999: New Taenidium

(trace fossil) in the Upper Cretaceous chalk of northwestern
Europe. Bull. Geol. Soc., Denmark 46, 47—51.

Buckman J.O. 1996: Heimdallia from the Lower Carboniferous of

Ireland: H. mullaghmori a new ichnospecies, and re-evaluation of
the three-dimensional format of the ichnogenus. Ichnos 5, 43—51.

Buckman J.O. 2001: Parataenidium, a new taenidium-like ichnoge-

nus from the carboniferous of Ireland. Ichnos 8, 2, 83—97.

Carvalho C.N., Viegas P.A. & Cachão 2007: Thalassinoides and its

producer: populations of Mecochirus buried within their bur-
row system, Boca do Chapim Formation (Lower Cretaceous),
Portugal. Palaios 22, 104—109.

D’Alessandro A. & Bromley R. G. 1987: Meniscate trace fossils

and the Muensteria—Taenidium problem. Palaeontology 30, 4,
743—763.

Eberli G.P. 1988: The evolution of the southern continental margin

of the Jurassic Tethys Ocean as recorded in the Allgau Forma-
tion of the Australpine Nappes of Graubunden (Switzerland).
Eclogae Geol. Helv. 81, 175—214.

Ekdale A.A. & Bromley R.G. 2003: Paleoethologic interpretation of

complex Thalassinoides in shallow-marine limestones, Lower
Ordovician, southern Sweden. Palaeogeogr. Palaeoclimatol.
Palaeoecol. 192, 221—227.

Ekdale A.A. & Mason T.R. 1988: Characteristic trace-fossil associ-

ations in oxygen-poor sedimentary environments. Geology 16,
720—723.

Fernandes A.C.S. & Carvalho I.S. 2006: Invertebrate ichnofossils

from the Adamantina Formation (Bauru Basin, Late Creta-
ceous), Brazil. Rev. Brasileira Paleontologia 9, 211—220.

Fillion D. & Pickerill R.K. 1990: Ichnology of the Upper Cambrian?

To Lower Ordovician Bell Island and Wabana groups of eastern
Newfoundland, Canada. Palaeontogr. Canadiana 7, 1— 119.

Frey R.W. 1970: Trace fossils of Fort Hays limestone Member of

Niobrara chalk (Upper Cretaceous), West-central Kansas.
Univ. Kan. Paleont. Contrib. 53, 1—41.

Fu S. 1991: Funktion, Verhalten und Einteilung fucoider und lo-

phocteniider Lenebsspuren. Cour. Forsch.-Inst. Senckenberg
135, 1—79.

Fürsich F.T. 1973: A revision of the trace fossils Spongeliomorha,

Ophiomorpha and Thalassinoides. Neu. Jb. Geol. Paläont., Mh.
12, 719—735.

Fürsich F.T. 1974: Ichnogenus Rhizocorallium. Paläont. Z. 48,

16—28.

Gaździcki A., Michalík J., Planderová E. & Sýkora M. 1979: An

Upper Triassic—Lower Jurassic sequence in the Krížna nappe
(West Tatra Mountains, West Carpathians, Czechoslovakia).
Západ. Karpaty, Geol. 5, 119—148.

Gooday A.J., Levin L.A., Thomas C.L. & Hecker B. 1992: The dis-

tribution and ecology of Bathysiphon filiformis Sars and B.
major de Folin (Protista, Foraminiferida) on the continental
slope off North Carolina. J. Foram. Res. 22, 129—146.

373

TRACE-FOSSIL ASSEMBLAGES IN “SPOTTED” (FLECKENMERGEL—FLECKENKALK) DEPOSITS

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

Gooday A.J., Bernhard J.M., Levin L.A. & Suhr S.B. 2000: Fora-

minifera in the Arabian Sea oxygen minimum zone and other
oxygen-deficient settings: taxonomic composition, diversity,
and relation to metazoan faunas. Deep-Sea Res. II 47, 25—54.

Gooday A.J., Pond D.W. & Bowser S.S. 2002: Ecology and nutrition

of the large agglutinated foraminiferan Bathysiphon capillare in
the bathyal NE Atlantic: distribution within the sediment pro-
file and lipid biomarker composition. Mar. Ecol., Progress Ser.
245, 69—82.

Gradziński M., Tyszka J., Uchman A. & Jach R. 2004: Large micro-

bial-foraminiferal oncoids from condensed Lower—Middle Ju-
rassic deposits: a case study from the Tatra Mountains, Poland.
Palaeogeogr. Palaeoclimatol. Palaeoecol. 213, 133—151.

Gross P., Filo I., Halouzka R., Hraško J., Havrila M., Kováč P.,

Maglay J., Mello J. & Nagy A. 1994: Geological Map of South-
ern and Eastern Part of Orava, 1 : 50,000. Geol. Ústav Dionýza
Štúra (in Slovak).

Häusler H., Plašienka D. & Polák M. 1993: Comparison of Mesozoic

successions of the Central Eastern Alps and the Central West-
ern Carpathians. Jb. Geol. Bundesanst. 136, 715—739.

Hertweck G., Wehrmann A. & Liebezeit G. 2007: Bioturbation

structures of polychaetes in modern shallow marine environ-
ments and their analogues to Chondrites group traces. Palaeo-
geogr. Palaeoclimatol. Palaeoecol. 245, 382—389.

Jach R. 2002: Lower Jurassic spiculite series from the Krížna Unit

in the Western Tatra Mts, Western Carpathians, Poland. Ann.
Soc. Geol. Pol. 72, 131—144.

Jach R. 2005: Storm-dominated deposition of the Lower Jurassic

crinoidal limestones in the Krížna unit, Western Tatra Moun-
tains, Poland. Facies 50, 561—572.

Jacobshagen V. 1965: Die Allgäu-Schichten (Jura – Fleckenmergel)

zwischen Wettersteingebirge und Rhein. Jb. Geol. Bundesanst.
108, 1—114.

Jaglarz P. & Uchman A. 2010: A hypersaline ichnoassemblage from

the Middle Triassic carbonate ramp of the Tatricum domain in
the Tatra Mountains, Southern Poland. Palaeogeogr. Palaeo-
climatol. Palaeoecol. 292, 71—81.

Keighley D.G. & Pickerill R.K. 1994: The ichnogenus Beaconites

and its distinction from Ancorichnus and Taenidium. Palaeon-
tology 37, 2, 305—337.

Koša E. 1998: Lithostratigraphy and depositional environment of

Lower-Middle Jurassic crinoidal limestone formations of the
Vysoká Nappe Unit (Malé Karpaty Mts, Western Carpathians).
Geol. Carpathica 49, 329—339.

Kotake N. 1989: Paleoecology of the Zoophycos producers. Lethaia

22, 327—341.

Lavayele M.S.S., Duineveld G.C.A., Berghuis E.M., Kok A. &

Witbaard R. 2002: A comparison between the megafauna
communities on the N.W. Iberian and Celtic continental mar-
gins – effects of coastal upwelling? Progress in Oceanography
52, 459—476.

Lefeld J., Gaździcki A., Iwanow A., Krajewski K. & Wójcik K.

1985: Jurassic and Cretaceous litostratigraphic units in the
Tatra Mts. Stud. Geol. Pol. 84, 7—93.

Levin L.A., Gage J.D., Martin C. & Lamont P.A. 2000: Macrobenthic

community structure within and beneath the oxygen minimum
zone, NW Arabian Sea. Deep-Sea Res. II 47, 189—226.

Löwemark L. & Schäfer P. 2003: Ethological implications from

a detailed X-ray radiograph and

C study of the modern deep-

sea Zoophycos. Palaeogeogr. Palaeoclimatol. Palaeoecol. 192,
101—121.

Löwemark L., Lin Y., Chen H.-F., Yang T.-N., Beier C., Werner F.,

Lee C.-Y., Song S.-R. & Kao S.-J. 2006: Sapropel burn-down
and ichnological response to late Quaternary sapropel forma-
tion in two ~ 400 ky records from the Eastern Mediterranean
Sea. Palaeogeogr. Palaeoclimatol. Palaeoecol. 239, 406—425.

Martin K.D. 2004: A re-evaluation of the relationship between trace

fossils and dysoxia. Geol. Soc. London, Spec. Publ. 228, 141—156.

Miller III W., Stefani C. & Grandesso P. 2004: Alternation of eco-

logic regimes in a deep-marine carbonate basin: calciturbidite
trace fossils from the Cretaceous Scaglia Rossa, northeastern
Italy. Palaeogeogr. Palaeoclimatol. Palaeoecol. 204, 317—330.

Mišík M. 1959: Lithologishes Profil durch die Schichtenfolge des

höheren Lias („Fleckenmergel“) des Gebirges Belanské Tatry.
[Litologický profil súvrstvím vyššieho liasu („Fleckenmergel”)
Belanských Tatier.] Geol. Sbor. Slov. Akad. Vied 10, 183—187
(in Slovak).

Mišík M. 1964: Lithofazielles Studium des Lias der Grossen Fatra

und Westteils der Niederen Tatra. Sbor. Geol. Vied, Západ.
Karpaty, 7—89.

Mišík M. & Rakús M. 1964: Bemerkungen zu räumlichen Beziehun-

gen des Lias und zur Paläogeographie des Mesozoikum in der
Grossen Fatra. Zbor. Geol. Vied, Západ. Karpaty 1, 159—199.

Monaco P. 1995: Relationships between trace-fossil communities

and substrate characteristics in some Jurassic pelagic deposits in
the Umbria-Marche Basin, central Italy. Geobios, Mem. Spec.
18, 299—311.

Olivero D. 2003: Early Jurassic to Late Cretaceous evolution of

Zoophycos in the French Subalpine Basin (southeastern France).
Palaeogeogr. Palaeoclimatol. Palaeoecol. 192, 59—78.

Parisi G., Ortega-Huertas M., Nocchi M., Palomo I., Monaco P. &

Martinez F. 1996: Stratigraphy and geochemical anomalies of
the Early Toarcian oxygen-poor interval in the Umbria-Marche
Apennines (Italy). Geobios 29, 469—484.

Pemberton S.G. & Frey R.W. 1982: Trace fossil nomenclature and the

Planolites—Palaeophycus dilemma. Paleontology 56, 843—881.

Peters S.E. 2007: The problem with the Paleozoic. Paleobiology 33,

165—181.

Plašienka D. 2003: Dynamics of Mesozoic pre-orogenic rifting in the

Western Carpathians. Mitt. Österr. Geol. Gesell. 94, 79—98.

Polák M. & Ondrejičková A. 1993: Lithology, microfacies and bio-

stratigraphy of radiolarian limestones, radiolarites in the
Krížna Nappe of the Western Carpathians. Miner. Slovaca 25,
391—410.

Polák M., Ondrejičková A. & Wieczorek J. 1998: Lithobiostrati-

graphy of the Ždiar Formation of the Krížna nappe (Tatry Mts.)
Slovak Geol. Mag. 4, 35—52.

Pruss S.B., Finnegan S., Fischer W.W. & Knoll A.H. 2010: Carbon-

ates in skeleton-poor seas: new insights from Cambrian and
Ordovician strata of Laurentia. Palaios 25, 73—84.

Rajchel J. & Uchman A. 2012: Ichnology of Upper Cretaceous

deep-sea thick-bedded flysch sandstones: Lower Istebna Beds,
Silesian Unit (Outer Carpathians, southern Poland). Geol. Car-
pathica 63, 107—120.

Rakús M. 1963: Distribution of the Toarcian lithofacies in the cen-

tral zone of the West Carpathians. Geol. Sbor. Slov. Akad. Vied
14, 19—27.

Rakús M. 1964: Paläontologische studien im Lias der Grossen Fatra

und Westteils der Niederen Tatra. Sbor. Geol. Vied, Západ.
Karpaty, 94—154.

Rakús M. 1984: Skladaná skala – quarry. Guide to geological excur-

sion in The West Carpathians Mts. Guide to geological excur-
sion. IGCP project No. 198. The evolution of the northern
margin of Tethys. Geol. Ústav Dionýza Štúra, Bratislava, 1— 99.

Raucsik B. & Varga A. 2008: Climato-environmental controls on

clay mineralogy of the Hettangian—Bajocian successions of the
Mecsek Mountains, Hungary: An evidence for extreme conti-
nental weathering during the early Toarcian oceanic anoxic
event. Palaeogeogr. Palaeoclimatol. Palaeoecol. 265, 1—2, 31,
1—13.

Rhoads D.C. & Morse J.W. 1971: Evolutionary and ecologic signif-

icance of oxygen-deficient marine basins. Lethaia 4, 413—428.

374

ŠIMO and TOMAŠOVÝCH

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2013, 64, 5, 355—374

Rhoads D.C., Mulsow S.G., Gutschick R., Baldwin C.T. & Stolz

J.F. 1991: The dysaerobic zone revisited: a magnetic facies?
Geol. Soc. London, Spec. Publ. 58, 187—199.

Riedel B., Zuschin M. & Stachowitsch M. 2012: Tolerance of benthic

macrofauna to hypoxia and anoxia in shallow coastal seas:
a realistic scenario. Mar. Ecology, Progress Ser. 458, 39—52.

Rodríguez-Tovar F.J. & Uchman A. 2010: Ichnofabric evidence for

the lack of bottom anoxia during the Lower Toarcian oceanic
anoxic event in the Fuente de la Vidriera section, Betic Cordil-
lera, Spain. Palaios 25, 576—587.

Santantonio M. & Carminati E. 2011: Jurassic rifting evolution of

the Apennines and Southern Alps (Italy): parallels and differ-
ences. Geol. Soc. Amer. Bull. 123, 468—484.

Savrda C.E. & Bottjer D.J. 1986: Trace-fossil model for reconstruc-

tion of paleo-oxygenation in bottom waters. Geology 14, 3—6.

Savrda C.E. & Bottjer D.J. 1991: Oxygen-related biofacies in ma-

rine strata: an overview and update. In: Tyson R.V. & Pearson
T.H. (Eds.): Modern and ancient continental shelf anoxia.
Geol. Soc., Spec. Publ. 58, 201—219.

Schlirf M. 2011: A new classification concept for U-shaped spreite

trace fossils. Neu. Jb. Geol. Paläont., Abh. 260, 1, 33—54.

Schlögl J., Rakús M., Krobicki M., Matyja B.A., Wierzbowski A.,

Aubrecht R., Sitár V. & Józsa S. 2004: Benatina Klippe – litho-
stratigraphy, biostratigraphy, palaeontology of the Jurassic and
Lower Cretaceous deposits (Pieniny Klippen Belt, Western Car-
pathians, Slovakia). Slovak Geol. Mag. 10, 241—262.

Seilacher A. 1967: Bathymetry of trace fossils. Mar. Geol. 5, 413—428.
Seilacher A. 1990: Paleozoic trace fossils. In: Said R. (Ed.): The geo-

logy of Egypt. A.A. Balkema, Rotterdam, 649—670.

Seilacher A. 2007: Trace fossil analysis. Springer, Berlin, Heidel-

berg, New York, 1—226.

Smith C.R., Levin L.A., Hoover D.J., McMurtry G. & Gage J.D. 2000:

Variations in bioturbation across the oxygen minimum zone in the
northwest Arabian Sea. Deep-Sea Res. II 47, 227—257.

Sulser H. & Furrer H. 2008: Dimerelloid rhynchonellide brachiopods

in the Lower Jurassic of the Engadine (Canton Graubünden, Na-
tional Park, Switzerland). Swiss J. Geosci. 101, 1, 203—222.

Šimo V. 2012: The largest fossil agglutinated foraminifera Bathysi-

phon  boucoti  Miller  2005  a tube  of  polychaete  annelids?  Ag-
glutinated  tubular  structure  from  Lower  Jurassic  limestone
(Janovky  Formation,  West  Carpathians).  13.  Czech-Slovak-
Polish Paleontological Conference, Abstract Book, 65—66.

Taylor A., Goldring R. & Gowland S. 2003: Analysis and applica-

tion of ichnofabrics. Earth Sci. Rev. 60, 227—259.

Thierry J. 2000: Middle Toarcian. In: Dercourt J., Gaetani M.,

Vrielynck B.,

Barrier E., Biju-Duval B., Brunet M.F., Cadet

J.P., Crasquin S. & Sandulescu M. (Eds.): Atlas of Peri-Tethys
Palaeogeographical Maps. Explanatory notes. Commission for
the Geological Map of the World, Paris, 71—83.

Thompson J.B., Mullins H.T., Newton C.R. & Vercoutere T.L.

1985: Alternative biofacies model for dysaerobic communities.
Lethaia 18, 167—179.

Tyszka J. 1994a: Paleoenvironmental implications from ichnological

and microfaunal analyses of Bajocian spotty carbonates, Pieniny
Klippen Belt, Polish Caprathians. Palaios 9, 175—187.

Tyszka J. 1994b: Response of Middle Jurassic benthic foraminiferal

morphogroups to dysoxic/anoxic conditions in the Pieniny

Klippen belt, Polish Carpathians. Palaeogeogr. Palaeoclimatol.
Palaeoecol. 110, 55—81.

Tyszka J. 2001: Microfossil assemblages as bathymetric indicators of

the Toarcian/Aalenian “Fleckenmergel” – facies in the Car-
pathian Pieniny Klippen Belt. Geol. Carpathica 52, 147—158.

Uchman A. 1992: Ichnogenus Rhizocorallium in the Paleogene flysch

(Outer Western Carpathians, Poland). Geol. Carpathica 43,
57—60.

Uchman A. 1995: Taxonomy and palaeoecology of flysch trace fos-

sils: The Marnoso arenacea formation and associated facies
(Miocene, Northern Apennines, Italy). Beringeria 15, 1—115.

Uchman A. 1998: Taxonomy and ethology of flysch trace fossils:

Revision of the Marian Książkiewicz collection and studies of
complementary material. Ann. Soc. Geol. Pol. 68, 105—218.

Uchman A. 1999: Ichnology of the Rhenodanubian Flysch (Lower Cre-

taceous—Eocene) in Austria and Germany. Beringeria 25, 67—173.

Uchman A. & Gaździcki A. 2006: New trace fossils from the La

Meseta Formation (Eocene) of Seymour Island, Antarctica.
Polish Polar Res. 27, 2, 153—170.

Uchman A. & Myczyński R. 2006: Stop B3.14 – Lejowa Valley:

eastern of the Polana Huty Lejowe Alp – Upper Sinemurian—
Lower  Pliensbachian  spotted  limestones  (Fig. B3.40).  In:
Wierzbowski A., Aubrecht R., Golonka J., Gutowski J., Kro-
bicki  M.,  Matyja  B.A.,  Pieńkowski  G.  &  Uchman  A.  (Eds.):
Jurassic  of  Poland  and  adjacent  Slovakian  Carpathians.  Filed
Trip Guidebook of 7th International Congress on the Jurassic
System, Poland, Kraków, September, 6—18. Polish Geological
Institute, Warsaw, 114—116.

Uchman A., Rodríguez-Tovar F.J., Machaniec E. & Kędzierski M.

2013: Ichnological characteristics of Late Cretaceous hemipe-
lagic and pelagic sediments in a submarine high around the
OAE-2 event: a case from the Rybie section, Polish Carpathians.
Palaeogeogr. Palaeoclimatol. Palaeoecol. 370, 222—231.

Van de Schootbrugge B., Bachan A., Suan G., Richoz S. & Payne J.

2013: Microbes, mud and methane: cause and consequence of
recurrent Early Jurassic anoxia following the end-Triassic
mass extinction. Palaeontology 56, 685—709.

Wetzel A. 1981: Ökologische und stratigraphische Bedeutung bioge-

ner Gefüge in quartären Sedimenten am NW-afrikanischen Kon-
tinentalrand. “Meteor” Forschungs-Ergebnisse, C 34, 1—47.

Wetzel A. 1991: Ecologic interpretation of deep-sea trace fossil com-

munities. Palaeogeogr. Palaeoclimatol. Palaeoecol. 85, 47—69.

Wetzel A. & Uchman A. 1998: Biogenic sedimentary structures in

mudstones – An overview. In: Schieber J., Zimmerle W. &
Sethi P. (Eds.): Shales and mudstones. I. Schweizerbart, Stut-
tgart, Germany, 351—369.

Wetzel A. & Werner F. 1981: Morphology and ecological signifi-

cance of Zoophycos in deep-sea sediments off NW Africa.
Palaeogeogr. Palaeoclimatol. Palaeoecol. 32, 185—212.

Wieczorek J. 1995: Trace fossils from Fleckenmergel facies (Juras-

sic) of the Tatra Mts. Geobios, Mem. Spec. 18, 425—431.

Zaton M., Marynowski L., Szczepanik P., Bond D.P.G. & Wignall

P.B. 2009: Redox conditions during sedimentation of the Mid-
dle Jurassic (Upper Bajocian-Bathonian) clays of the Polish
Jura (south-central Poland). Facies 55, 103—114.

Zimmerle W. & Sethi P. (Eds.) 1998: Shales and mudstones. I.

Schweizerbart, Stuttgart, Germany, 351—369.