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Review
Glaciation-induced features or sediment
gravity flows eAn analytic review
Mats O. Mol
en
Ume
a FoU AB, Vallmov 61, S-903 52 Ume
a, Sweden
Abstract For more than 150 years, geologic characteristics claimed to be evidence for pre-Pleistocene
glaciations have been debated. Advancements in recent decades, in understanding features generated by
mainly glacial and mass flow processes, are here reviewed. Detailed studies of data offered in support of pre-
Pleistocene glaciations have led to revisions that involve environments of mass movements. Similarities and
differences between Quaternary glaciogenic and mass movement features are examined, to provide a more
systematic methodology for analysing the origins of more ancient deposits. Analyses and evaluation of data are
from a) Quaternary glaciogenic sediments, b) formations which have been assigned to pre-Pleistocene gla-
ciations, and c) formations with comparable features associated with mass movements (and occasionally
tectonics). Multiple proxies are assembled to develop correct interpretations of ancient strata. The aim is not
per se to reinterpret specific formations and past climate changes, but to enable data to be evaluated using a
broader and more inclusive conceptual framework.
Regularly occurring pre-Pleistocene features interpreted to be glaciogenic, have often been shown to have
few or no Quaternary glaciogenic equivalents. These same features commonly form by sediment gravity flows
or other non-glacial processes, which may have led to misinterpretations of ancient deposits. These features
include, for example, environmental affinity of fossils, grading, bedding, fabrics, size and appearance of
erratics, polished and striated clasts and surfaces (“pavements”), dropstones, and surface microtextures.
Recent decades of progress in research relating to glacial and sediment gravity flow processes have resulted in
proposals by geologists, based on more detailed field data, more often of an origin by mass movements and
tectonism than glaciation.
The most coherent data of this review, i.e., appearances of features produced by glaciation, sediment
gravity flows and a few other geological processes, are summarized in a Diamict Origin Table.
Keywords Diamictite, Tillite, Sediment gravity flow (SGF), Striation, Groove, Dropstone, Paleoclimate,
Fossil vegetation, Glaciogenic proxies, Surface microtexture, Late Paleozoic ice age
© 2023 The Author(s). Published by Elsevier B.V. on behalf of China University of Petroleum (Beijing). This
is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-
nd/4.0/).
Received 9 November 2021; revised 28 April 2023; accepted 14 August 2023; available online xxx
E-mail address: mats.extra@gmail.com.
Peer review under responsibility of China University of Petroleum (Beijing).
Available online at www.sciencedirect.com
ScienceDirect
journal homepage: http://www.journals.elsevier.com/journal-of-palaeogeography/
Journal of Palaeogeography, 2023, ▪(▪): 1e59
https://doi.org/10.1016/j.jop.2023.08.002
2095-3836/© 2023 The Author(s). Published by Elsevier B.V. on behalf of China University of Petroleum (Beijing). This is an open access article
under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Please cite this article as: Mol
en, M.O., Glaciation-induced features or sediment gravity flows eAn analytic review, Journal of Palaeogeography,
https://doi.org/10.1016/j.jop.2023.08.002
Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
1.1. Structure of the current paper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
1.2. Bias in diamictite research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
1.3. Geologic features produced by sediment gravity flows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2. Similarities and differences between glaciogenic and other geologic features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.1. Geographical extent, dating, climate and fossils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.1.1. Geographical extent .................................................................. 00
2.1.2. Correlations and dating ............................................................... 00
2.1.3. Fossil vegetation and climate ........................................................... 00
2.2. Till structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.2.1. More mass flows and marine sediments than basal glaciogenic sediments ....................... 00
2.2.2. No rock flour and density of deposits .................................................... 00
2.2.3. Correlation between clast size and thickness of strata ....................................... 00
2.2.4. Grading in sediments ................................................................. 00
2.2.5. Bedding and amalgamation ............................................................ 00
2.2.6. Presence of soft sediment structures ..................................................... 00
2.2.7. Fabrics ............................................................................. 00
2.3. Erratics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.3.1. Erratics esimilarities ................................................................. 00
2.3.2. Erratics edifferences ................................................................. 00
2.4. Polished, faceted and striated clasts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.5. Striated, grooved and polished surfaces/pavements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.5.1. Presence of surfaces/pavements ......................................................... 00
2.5.2. Formation surfaces/pavements ......................................................... 00
2.5.3. Differences displayed by surfaces/pavements .............................................. 00
2.6. Rock polish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.7. Iceberg keel scour marks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.8. Boulder pavements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.9. Erosional landforms, lineations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.10. Erosional landforms eplucking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.11. Glacial and non-glacial valleys and fjords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.11.1. Valleys egeneral appearance .......................................................... 00
2.11.2. Valleys eshape ..................................................................... 00
2.11.3. Valleys efjords ..................................................................... 00
2.12. Glaciofluvial deposits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.12.1. Eskers ............................................................................ 00
2.12.2. Tunnel valleys ...................................................................... 00
2.12.3. Raised channels, eskers and tunnel valleys ............................................... 00
2.13. Dropstones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.13.1. Dropstones, similarities .............................................................. 00
2.13.2. Dropstones, differences .............................................................. 00
2.14. Laminated sediments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.15. Glaciomarine (and lake) diamictites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.16. Periglacial structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.17. Soft sediment deformation, tectonism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
2.18. Scanning electron microscopy (SEM) studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
3. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
4. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
5. Main research interest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
6. Conflicts of interest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00
Acknowledgements .............................................................................. 00
References ..................................................................................... 00
Supplementary data ............................................................................. 00
.............................................................................................. 00
2M.O. Mol
en
Please cite this article as: Mol
en, M.O., Glaciation-induced features or sediment gravity flows eAn analytic review, Journal of Palaeogeography,
https://doi.org/10.1016/j.jop.2023.08.002
Terminology of features/words that may be inter-
preted differently
Dropstone and lonestone: Dropstone is a genetic
label for a clast that has been dropped into water from
ice. This label may also be used for clasts dropped by
other agents, like from floating vegetation. In the
current paper the label dropstone refers to any
outsized clasts which have been interpreted in the
literature to be dropped from ice or other agents, even
if that interpretation may not be valid. A non-genetic
term for outsized clasts is lonestone.
Groove: Commonly defined in width as >10 mm up
to a few meters or more. Marine geologists may label
any large linear erosional (V-shaped) forms as grooves
(Nwoko et al., 2020a), even if they are kilometers in
width, but in the current paper the definition is used
for erosion by tools.
Striation: Commonly defined as <10 mm in width.
Tillite and “tillite”:This label is a genetic term,
and by definition a lithified till. Any ancient diamictite
which has been classified as tillite by former re-
searchers, even if the evidence from recent research
indicates a non-glacial origin of the deposit, is here
also labeled tillite. If the word diamictite should be
used instead of tillite, then the current or most com-
mon interpretation of the deposit is missed. There-
fore, for the discussions concerning the interpretation
of the origin of a deposit, the term will be marked
within quotation marks, i.e., “tillite,”independent of
the most recent interpretation.
General: Quotation marks on single words in the
text are commonly used when the original interpre-
tation may not be true, but have to be referred to.
1. Introduction
1.1. Structure of the current paper
Diamictites are often interpreted to have been
formed in a cold climate environment based on the
general structure of the deposits, associated geologic
features, and polar wander paths. Geochemical data
may be used to strengthen the interpretation of
glaciation, but these display apparent shortcomings
and are often dependent on local environments, and
often not conforming to current models of changing
climates through Earth's history (Frimmel, 2010;
Bahlburg and Dobrzinski, 2011;Garzanti and Resentini,
2016;Macdonald, 2020;Caetano-Filho et al., 2021;
Mikhailova et al., 2021;Rogov et al., 2021;Scotese
et al., 2021;Retallack et al., 2021;Smith and Swart,
2022).
Similarities in outcrop of many glaciogenic features
may be produced by different geologic processes
(Isbell et al., 2021), and therefore more detailed
criteria are needed for interpretation. The current
paper analyses and reviews a broad range of such
geologic features, i.e., the difference in appearance
of the most important geologic features produced by
glaciation and processes which may mimic glaciogenic
geologic features. The basic assumption is that the
recent is better known than the past. This is an
actualistic approach, i.e., the principle that the same
processes and natural laws applied in the distant past
are the same as those active today. This actualistic
approach is followed by not using models or long-
standing interpretations, but instead mainly field
studies and experiments. Recent progress in studies of
sediment gravity flow (SGF) (used interchangeably
with mass flow) processes, glaciogenic and a few other
processes which may be relevant, are applied when
documenting the origin of ancient deposits. Where
there is a lack of published data, documentation is
compiled or otherwise acknowledged as missing. It
may be questioned that mainly Quaternary examples
of geologic features are used in comparison to features
from the much longer pre-Quaternary time scales, but
as the more recent geologic features are better
known, and it is assumed that natural laws have not
changed, this is not a critical problem. Therefore,
unintentionally, this work may have become contro-
versial, not because of the compilation of research
data, but because of longstanding interpretations of
many ancient deposits.
The current paper is to a large part biased by
reference to well documented and extensive outcrops.
The main exception is the documentation of outsized
clasts, because lonestones are often interpreted to be
dropstones and therefore are commonly suggested to
be evidence for glaciation (e.g., Rodríguez-L
opez
et al., 2016;L
opez-Gamundí et al., 2021;Le Heron
et al., 2021a;Bronikowska et al., 2021). The inten-
tion is to design questions for field research, rather
than to present solutions to all problems of interpre-
tation of ancient deposits. The appearance of geologic
features which are described in great detail will be
documented, and former interpretations may not be
followed. Different processes which may create similar
features are documented by using process-related or
“process-sedimentological”principles “to consider
alternative hypotheses”(Shanmugam, 2012). Relevant
field data is summed up in a Diamict Origin Table,asa
guide to the interpretation of the geologic features
which have been documented and discussed
(Appendix).
Glaciation-induced features or sediment gravity flows 3
Please cite this article as: Mol
en, M.O., Glaciation-induced features or sediment gravity flows eAn analytic review, Journal of Palaeogeography,
https://doi.org/10.1016/j.jop.2023.08.002
1.2. Bias in diamictite research
Ever since diamictites were first interpreted to be
pre-Pleistocene ice age deposits, by Ramsay in 1855
for some Permian boulder deposits in England
(Hoffman, 2011), there has been much controversy
over their interpretation. Glaciogenic proxies are
documented in order to find stratigraphic intervals
displaying glaciations. Pre-Pleistocene formations
which are, or have been, interpreted to have formed
by glaciations are documented from the Archean,
Proterozoic, and all periods of the Phanerozoic
(Hambrey and Harland, 1981;Caputo and Santos,
2020;Youbi et al., 2021) sometimes even in the tro-
pics and indicating low elevations (Soreghan et al.,
2014), including five different episodes during the
Cretaceous (Alley et al., 2020). The most accepted and
geologically important glaciations are in the Paleo-
proterozoic, the Neoproterozoic, the Upper Ordovi-
cian, and the Late Paleozoic (i.e., LPIA; recently dated
to 372-259 million years; Pauls et al., 2021). Models of
climatic change have been erected, and in the litera-
ture there are numerous discussions of e.g., Snowball
or Slushball Earth during the Neoproterozoic (e.g., Bai
et al., 2020).
However, the current interpretation of a strati-
graphic interval commonly biases the research ques-
tions, observations and measurements that are
documented. Frequently, mainly data supposed to be
relevant for the current interpretation are reported.
These biases have in some cases hindered alternative
interpretations from being fully investigated. There-
fore the features which are described in the literature
often contain too few details to establish if the de-
posits have originated from glacial action, SGF or by
any other means. Observations made 30 to 50 years
ago may now be of particular interest, due to the
growth of knowledge in the research field of mass
movements. For example, a clast or a surface with
striations is often reported to have been glacially
striated if present in connection to a diamictite even
though these also are produced by SGFs (Atkins, 2003).
In other words, features which may be formed in
different environments are reported, but diagnostic
features may not be documented or discussed. Single
or even groups of features which display appearances
partly similar to and interpreted to be glaciogenic
features, may subsequently be shown to be very
different from Pleistocene and more recent glacio-
genic features. In short, the question of the origin of
diamictites has in some cases become a part of a sci-
entific paradigm (Kuhn, 1970;Shanmugam, 2016)
connected to long-term climatic correlations (Young,
2013;Shields et al., 2022).
Starting with a paper by Crowell (1957), it has been
recognized that many “ice-age remains”have been
deposited by different kinds of SGFs. Later, Scher-
merhorn published a comprehensive review which
documented the evidence for a SGF origin of ancient
diamictites, shown in his classic work on Late Pre-
cambrian diamictites (Schermerhorn, 1974,1976,
1977). Recent research has uncovered growing evi-
dence of non-glacial transport, and diamictites have
more often been interpreted as glaciomarine and
often considered as parts of interglacial periods. This
includes approximately 95% of all “glaciogenic”de-
posits, i.e., sediments which may contain an abun-
dance of marine fossils, and to a large part are made
up of SGF deposits (Eyles, 1993;Gonz
alez and Glasser,
2008;Isbell et al., 2016,2021;L
opez-Gamundí et al.,
2016,2021;Assine et al., 2018;Vesely et al., 2018;
Rosa et al., 2019;Sterren et al., 2021;Mol
en and Smit,
2022). These recent findings make it more difficult to
determine if the deposits had been produced primarily
by glaciation or are non-glacial marine. In this case
often the only “unequivocal”evidence for glacial in-
fluence is considered to be dropstones, especially if
outsized clasts occur in rhythmites, but also if SGF
deposits or stratified diamictites display outsized
clasts (e.g., Ezpeleta et al., 2020). Included with
dropstones, striated clasts and surfaces (“pave-
ments”) are commonly referred to as evidence for
glaciation without discussing alternative in-
terpretations in depth (e.g., Molnia, 1983a;Miall,
1983,1985;Eyles, 1993;Hoffman et al., 1998;Carto
and Eyles, 2012a;Rodríguez-L
opez et al., 2016;Le
Heron et al., 2017;Le Heron and Vandyk, 2019).
1.3. Geologic features produced by sediment
gravity flows
Gravity-induced slope processes include variations
of rock fall, slides, slumps, debris flows and turbidites.
Almost complete sedimentary sequences have been
documented, horizontally and/or vertically, which
show how mass movements have changed from e.g.,
slides to debris flows and finally to turbidity currents
(Ogata et al., 2019;Rodrigues et al., 2020;Kennedy
and Eyles, 2021). Sedimentary and erosional features
which commonly form from such processes, especially
those originating from cohesive debris flows, share
many similarities in appearance to glaciogenic fea-
tures and are present in many diamictites which had
been interpreted to be glaciogenic (e.g., Mol
en, 2017,
2021). Another process which shows similarities to
slope processes are land derived hyperpycnal flows.
Such flows can in some cases last for months. Even
though they have a different origin from slope
4M.O. Mol
en
Please cite this article as: Mol
en, M.O., Glaciation-induced features or sediment gravity flows eAn analytic review, Journal of Palaeogeography,
https://doi.org/10.1016/j.jop.2023.08.002
processes, they display similarities in the sedimenta-
tion process, and the deposits may be reworked and
transform into a full spectrum of SGFs (Zavala and
Arcuri, 2016;Shanmugam, 2019,2021b;Zavala,
2019,2020). Hyperpycnal flow deposits are therefore
included here in what is commonly described as SGF
deposits.
In Section 2 of this paper, differences between
features formed by glacial processes, SGFs and other
geologic processes which may produce landforms that
surficially resemble glaciogenic features, will be out-
lined in order to uncover a methodology to interpret
the origin of ancient outcrops. However, in the current
paper, the details of what kind of SGF or other mass
movement that has produced each geologic feature
during different geologic periods and in different
geographic areas, will not be discussed, in order to
keep the text shorter.
2. Similarities and differences between
glaciogenic and other geologic features
Kilfeather et al. (2010) stated that it may be
impossible to confidently identify a specific environ-
ment of deposition by macroscopic features and
textural criteria in restricted outcrops, but as docu-
mented below there are more unequivocal criteria
than is usually recognized.
There are differences in how glaciers erode the
basement, and also how glaciogenic material is depos-
ited, including all kinds of glaciofluvial material, but
the main processes are similar worldwide. If there is
glaciogenic material that has only been transported by
a glacier, such as supraglacial till, it will not acquire
many of the characteristics imposed by glacial forces.
The same holds for flow tills, if they are supraglacial
mass flows that have never been covered by a glacier.
This may also hold for some aspects of squeezed flow till
(Hicock, 1991;Hicock and Dreimanis, 1992b). Flow tills
are in any case difficult to differentiate from non-
glaciogenic mass flows, especially if they are formed
subaqueously (Evenson et al.,1977). Englacial till which
has been deposited as melt-out till also may not acquire
many glaciogenic features. However, material that is
deposited in a subglacial environment will display evi-
dence of glaciation (Mahaney, 2002;Mol
en, 2014).
Furthermore, supraglacial tills and other tills that have
not been transported at the base of a glacier are usually
a minor part of glaciogenic sediments, and they are
easily removed by later erosion, in contrast to basal till.
Many features which are interpreted to be evi-
dence of glaciation form in a wide range of environ-
ments (e.g., Eyles, 1993;Eyles and Boyce, 1998;
Atkins, 2003;Thompson, 2009). If clasts from one
environment are incorporated by a new process, e.g.,
tectonic material that is mixed with finer material and
beach/slope material in a debris flow, the origin of the
deposit may be difficult to uncover (e.g., Festa et al.,
2019). This mixing of different materials is common in
SGFs, and up to 50% of the material may be entrained
through erosion from the substrate along the path of
the flow (e.g., Thompson, 2009;Carto and Eyles,
2012a,2012b;Ortiz-Karpf et al., 2017;Ogata et al.,
2019;Nugraha et al., 2020;Rodrigues et al., 2020).
Eyles and Eyles (2000) described a “cement-mixer-
model”of how different sediments could mix.
Each of the features reviewed in Sections 2.1.-2.18
below is commonly referred to when exploring evi-
dence of glaciation. In addition, there are many
geologic features from “ancient ice-ages”which have
rarely or never been formed by Pleistocene or younger
glaciers. These features may be at odds with a gla-
ciogenic interpretation, but often at the same time
indicate a SGF and/or tectonic origin. Also, there are
some general problems in regard to “tillites”that do
not apply to SGFs, e.g., climate and correlations,
which are also discussed below.
2.1. Geographical extent, dating, climate and
fossils
2.1.1. Geographical extent
SGFs occur worldwide, independent of latitude,
and are therefore present in the same areas as the
more geographically restricted glaciers. Mountain
glaciers are areally restricted, but are present world-
wide if above the equilibrium-line altitude (e.g.,
Mahaney, 1990).
The geographic extents of deposits from “ancient
ice-ages”are often comparatively small and “tillites”
are often dispersed as separate outcrops (e.g.,
Deynoux and Trompette, 1981b;Eyles, 1993;Le Heron
et al., 2018a). There are two exceptions. The first is
the Ordovician deposits in northern Africa which cover
between 8 × 10
6
(Biju-Duval et al., 1981) and
20 × 10
6
km
2
(Fairbridge, 1979). The size difference
depends on whether the Arabian diamictites are
included or not. If the lesser Ordovician outcrops in
South Africa, Europe and South America are included,
the maximum hypothetical glaciated area is c.
40 × 10
6
km
2
(Le Heron et al., 2005,2018a;Ghienne
et al., 2007). The second exception is the LPIA out-
crops which cover maybe 30 × 10
6
km
2
if deposits from
separate basins in South America, Antarctica,
Australia, India, South Africa, Congo and Madagascar
are included (Gravenor, 1979). Parts of the Arabic
Glaciation-induced features or sediment gravity flows 5
Please cite this article as: Mol
en, M.O., Glaciation-induced features or sediment gravity flows eAn analytic review, Journal of Palaeogeography,
https://doi.org/10.1016/j.jop.2023.08.002