Trace Fossils

Question 1

are the biogenic sedimentary structures that record biological activities such as burrowing, walking, and feeding

Answer 1

Trace fossils ( ichnofossils)

Question 2

Trace fossil genera = ichnogenera
species = ichnospecies

Question 3

trace preserved on the top of the bed

Answer 3

Epirelief

Question 4

Entire trace preserved in three dimensions with sediments

Answer 4

Full Relief

Question 5

trace preserved on the lower surface of the bed

Answer 5

Hyporelief

Question 6

Collapsed burrow or trace formed on the surface of the bedding plane

Answer 6

Semirelief

Question 7

which are traces produced on the upper surface of a sediment then preserved by being quickly covered by a sediment of a different lithology

Answer 7

Epigene Traces

Question 8

which are structures filled within the host sediment, and therefore are homogeneous with the casting medium. The sediment infilling may have occurred either actively (by the organism itself) or passively (by some other process, after the organism has created the structure);

Answer 8

Endogene traces

Question 9

which are endogenic structures formed at a lithological interface or the junction between two beds

Answer 9

Intergene traces

Question 10

are found on the top of the strata of origin, being those ridges and grooves that
were formed by benthic organisms or infaunal burrows that have been exposed
by erosion

Answer 10

Epichnia

Question 11

are those traces that are found wholly within the casting medium, and therefore
can only have been made by an
infaunal organism.

Answer 11

Endichnia

Question 12

are ridges and grooves found on the soles of the beds of origin at their interfaces with other strata, representing the opposite of epichnia.

Answer 12

Hypichnia

Question 13

are traces that are made of material that is different from the surrounding medium, having either been actively filled by an organism or eroded out and re-covered by an alien sediment

Answer 13

Exichnia

Question 14

Resting or hiding traces formed during a
temporary pause in locomotion. Rather
than resting, the traces usually represent
feeding by stationary feeders or refuge

Usually as casts on the bottom of beds.
Morphology reflects the nature of the
undersurface of the resting organism

Answer 14

Cubichnia

Question 15

Dwelling traces formed by burrowing or
boring into the substrate. Traces represent
the long-term home of an animal that is
stationary in the burrow

Deep excavations of varying shape
found within beds. Usually form an
anastomosing tubular structure, or a
straight or a U- shaped burrow

Answer 15

Domichnia

Question 16

Escape structures formed when animal
moves rapidly upward to prevent burial by
a sudden influx of sediment or, more
rarely, laterally to avoid predators

Usually within beds in association with
domichnia. Sediment at proximal end of
burrow is reworked and lamination is
disturbed

Answer 16

Fugichnia

Question 17

Adjustment traces formed by infaunal
animals maintaining the position of their
burrow with respect to a gradually
agrading or degrading sea floor

Occurs within beds in association with
domichnia. Distinct laminations formed
parallel with the main burrow

Answer 17

Equilibrichnia

Question 18

Locomotion traces that represent directed
movement (from A to B). Includes walking,
crawling, tunneling, and running

Found as casts on the bottom of beds or
as epireliefs. Characteristically
continuous, elongate trails, sometimes
revealing motion of limbs

Answer 18

Repichnia

Question 19

Grazing traces formed by systematic
exploitation of a particular area of the
sediment for food

Horizontal traces found on or beneath the
bedding plane. Distinctive furrowed trails
with sinuous, meandering form but paths
rarely cross

Answer 19

Pascichnia

Question 20

Traps and farming traces formed by
animals that trap food particles or grow
algae. Structures represent feeding and
dwelling in a fixed area

Complicated horizontal network of
burrows with multiple openings to
surface. Usually preserved as hyporeliefs
on bottom bed surface

Answer 20

Agrichnia

Question 21

Traces which represent two functions:
deposit feeding and dwelling. Excavations
are made as the organism eats the
sediment and digests the food within it

Three-dimensional form usually found
within the bed. Generally horizontal but
more complex forms can have branched
networks of burrows

Answer 21

Fodinichnia

Question 22

indicative of substrate
found in fully lithified substrates, such as rocky coastlines and hard grounds

Answer 22

Trypanites ichnofacies

Question 23

generally developed in shallow water in the near -shore environment.
* it is typical of higher energy conditions associated with well
-sorted shifting sand. Deep, vertical, and
U
-shaped tubular hallows characterize the
ichnofacies

Answer 23

Skolithos ichnofacies

Question 24

reflects shallow water, lower energy conditions between the outer edge of the surf zone and storm wave base.
commonly developed in estuarine, lagoons, or in shelf environments.
it is a high diversity ichnofacie with crawling, deposit
feeding and shelter traces dominating organisms.

Answer 24

Cruziana ichnofacies

Question 25

• indicates deep water environments and is developed from the deep shelf to upper continental slope.
• associated with low oxygen environments and the low diversity in these ichnofacies may reflect oxygen-stressed
  conditions

Answer 25

Zoophycos ichnofacies

Question 26

• developed on the abyssal plain * reflects quiet, moderately well
  -oxygenated conditions
• most traces are found within the lower surface of beds
  and show a systematic grazing of the seafloor for food
  and detritus

Answer 26

Nereites ichnofacies

Question 27

defines the base of the Cambrian.
It is the feeding trace of a worm-like animal

Answer 27

Treptichnus pedum