Geology Reference
In-Depth Information
1
Introduction
(Australia),
the snowball garnets of Moine (Scotland),
V
sterbotten (Sweden), and Tasmania (Australia), or zircons
from Jack Hills (Australia) all tell important stories about the
Earth manifest at the
ä
Geoheritage
is wide-ranging in scope, encompassing glob-
ally, nationally, state-wide to locally signi
cant geological
sites that offer information on or insights into the formation
and evolution of the Earth, into the history of Science, or
sites which can be used for research, teaching, or reference.
Geoheritage also is wide-ranging in scale, transcending
terranes and major drainage basins to cliffs and bedding to
ner geological scales. In other words,
the metaphoric
of the story of the Earth should be
afforded geoheritage signi
“
alphabet
”
cance, as well as the
“
para-
graphs
of Earth history constructed from that
alphabet. To continue with the alphabet metaphor, the dif-
ferent stories of the Earth with different alphabet and lan-
guage in different locations globally should be afforded
equal geological signi
”
and
“
pages
”
ner scale features such as crystals and microfossils (Brocx
2008
; Brocx and Semeniuk
2007
). While many geological
reconstructions of Earth history commonly involve infor-
mation at large frames as in structural geology and meta-
morphic petrology, such research often begins at the ner
scale. As such,
cance and geoconservation.
Within south-western Australia, an accretionary cuspate
foreland, designated as a system of International importance,
contains a suite of wetlands, the Becher Point Wetlands that
record the history of the middle to late Holocene in their
stratigraphy and biota (Semeniuk
2007
). The wetlands man-
ifest various types of biota in their fossil record, including
pollen, algal spores, diatoms, charophytes, sponges, ostrac-
ods, gastropods, bivalves, and insect exoskeletons. This paper
explores the microscale geology and micropalaeontology of
the Becher Point Cuspate Foreland and its wetlands, con-
centrating on the small scale geology and the fossil record of
pollen and calci
ner scale features become important com-
ponents of the alphabet in reading the history of the Earth
yet, generally, the smallest scale of geological features in a
given area are not afforded the same status of signi
cance as
the larger scale features. However, we contend that, from the
point of view of geoconservation, if principles of superpo-
sition, unconformities, or the history embodied in lithology,
structures, lithological relationships, xenoliths, dropped
pebbles, folding, faults, relative ages, amongst many other
geological features are of geoheritage importance, then
microscopic versions of such patterns, for instance, encased
within crystals, or re
ed charophyte fructi
cations (gyrogonites),
to emphasise their signi
cant geoheritage values.
In the context of the First International Conference on
African and Arabian Geoparks held in November 2011 in El
Jadida, Morocco, we provide geoheritage practitioners with a
model of how the microscale geological aspects of an estab-
lished Ramsar site can be emphasised and ampli
ected in the microfossils, are also
important (e.g., constructing evolutionary history, recon-
structing magmatic history, or progressive and retrograde
metamorphism). That is, various
fl
ner scale geological fea-
tures such as Precambrian microfossils, or Phanerozoic mi-
crofossils that provide information about environments,
climates, or evolution, and crystals (in their composition,
arrangement, origin, marginal resorptions, zoning, inclu-
sions) tell a story of the Earth, and qualify to be assessed as
geologically signi
ed to bring
geoheritage and geoconservation into the consciousness of
land managers and decision makers. We focus on the micro-
scale geology and micropalaeontology of the Becher Point
area and their regional, National and International geoheritage
importance. This approach and outcome have applicability to
the northern African situations since therein there are many
Nature Reserves, National Parks, Ramsar sites, and World
Heritage sites (Baldwin et al.
1988
; Magin
2001
; Taleb and
Fennane
2011
; Ramsar Database
2012
) that, although they
have been inscribed on biological and other bases, have
potential to be described from a microscale geological point of
view such that their geodiversity and geoheritage values are
given more emphasis. Moreover, these Nature Reserves,
National Parks, Ramsar sites, and World Heritage sites in
northern Africa, though Research, Science and Education,
have potential to be used to emphasise that geodiversity
underpins biodiversity in already existing Reserves.
This paper presents information on the microscale geo-
logical features of the Becher Point area in terms of its
calcrete and carbonate grain dissolution, and the micropa-
laeontological features of a wetland basin (designated as
wetland 161 by Semeniuk (
2007
)) in terms of its pollen and
charophyte record, and its sponge spicule record and
taphonomy.
cant (Brocx and Semeniuk
2010
).
Thus, while the history of the Earth can be read at the
larger scale in the
of geology and in rock fabric
and texture, there is also a story that can be read in the
smaller scale features. Where signi
“
language
”
cant, these
ner scale
features need to be speci
cally addressed in geoconserva-
tion, or presented as part of the suite of features in any
proposed, or designated, Geopark. We argue that geocon-
servation should also focus on microscale features useful in
deciphering the history of the Earth, or that are associated
with the history of Earth Science. That is, what has been
assessed at the macroscale as geologically signi
cant fea-
tures in unravelling the history of the Earth (viz., stratigra-
phy, unconformities, structures, and igneous, metamorphic
and sedimentary lithology), and afforded geoheritage sig-
ni
cance, should also be directed to the microscale if similar
principles and patterns are present therein. It is also often at
this scale that the story of the Earth unfolds. The Pre-
cambrian microfossils of
the Bitter Springs Formation
