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THE FAULTED EARTH:
The Noble Qur’an Reads:
(And by the Earth that has its own fault) (LXXXVI:12)
This Qur’anic verse comes in the context of an oath, while
Allah (all glory be to Him) is definitely above giving such
a pledge. Consequently, this is understood as a device for
emphasis on the special significance of the matter by which
the oath is given. Now what is the special significance of
the faults of our planet?
Early commentators on the Holy Qur’an saw this significance
in the fracturing of the soil on watering it properly to
give a free, safe passageway for the tender, green shoots
coming out from the germinating seeds that are buried in the
soil, in the form of sprouting plants, which is very true.
Once you place a seed in the soil and water it properly, it
starts to germinate and a green shoot starts to penetrate
the soil and grow into a fully developed plant, bearing
beautiful flowers, delicious fruits and / or magnificent
wood. Such penetration takes place through tiny fractures
that develop in the soil as a result of its inflation by
hydrolysis and warping upwardly until thinning out to the
point of fracturing.
However, Earth Scientists have recently discovered that the
Earth’s outer rocky sphere (Lithosphere; which is about 65-
70 km thick under the oceans and 100-150 km thick under
continents) is broken up by a network of deep faults (or
rift systems) into 12 main rigid plates, added to a number
of small ones (microplates or platelets). These plates
(Text-fig. 1) float on a semi-molten plastic layer known as
the asthenosphere (the sphere of weakness) and move freely
away from or towards each other, and past one another. At
one boundary of each plate (or microplate), molten rock
(magma) rises to form strips of new ocean floor, and at the
opposite
boundary, the plate collides with the adjacent plate and
moves to sink underneath it, to be gradually consumed in the
underlying asthenosphere at exactly the same rate of sea
floor spreading at the opposite side (text-fig.2). An ideal,
rectangular, lithospheric plate would thus have one edge
growing at a mid-oceanic rift system (divergent boundary),
an opposite edge being gradually consumed into the
asthenosphere, below the over-riding or colliding plate
(convergent boundary) and other two edges sliding past the
adjacent plates along a system of transform faults (trans
current or transform fault boundaries). In this way, the
lithospheric plates are constantly shifting position on the
surface of the globe, despite their rigidity, and as they
are carrying continents with them, such continents are also
constantly drifting away or towards each other (text-figs.
3-8).
As an oceanic lithospheric plate is forced under another
oceanic or continental plate and its descending part starts
to melt, viscous magmas are intruded and squeezed between
the colliding plates, while lighter and more fluid ones are
extruded at the opposite edge to form island-arcs. These
eventually grow into subcontinents and continents, are
plastered to the margins of nearby continents or squeezed
between two colliding continents.
Such divergence, convergence and sliding of lithospheric
plates are not confined to ocean basins, but are also found
along the margins, as well as within and in between
continents. Both the Red Sea and the Gulf of California
troughs (which are extensions of oceanic rifts) are
currently widening at the rate of 3cm/year in the former and
6cm/year in the latter case. On the other hand, the
collision of the Indian Plate with the Eurasian Plate after
the consumption of the oceanic plate that was separating
them, resulted in the formation of the Himalayan Chain, with
the highest peaks on the surface of the Earth today.
Fault planes traversing the outer rocky sphere of the Earth
for tens of thousands of kilometres across the globe,
running in all directions for a depth of 65-150 km are among
the most salient features of our planet. These came to human
notice only after the Second World War and were only
understood within the framework of the concept of plate
tectonics which was fmally formulated in the late sixties
and the early seventies of this century (cf Hess, 1963;
Morely, 1963; Wilson, 1965; McKenzie, 1967; Maxwell and
others, 1970; Cox, 1973; Le Pichon and others, 1973; Dennis
and Atwater, l974etc).
These lithospheric faults are a globe — encircling system of
prominent rift zones (65- 150 km deep and tens of thousand
km long) along which lithospheric plates are displaced with
respect to one another divergently, convergently or sliding
past each other. They are also passageways through which the
trapped heat below the lithosphere is steadily released, and
different magmas are steadily outpouring. Molten magmas in
numerous hot spots, deep in the mantle, being less dense,
tend to rise up and descend down on cooling in the form of
hot plumes that create convection currents. Such currents
carry the lithospheric plates and move them across the
globe, with divergent, convergent and sliding relationships.
Divergence takes place at the rising tips of the convection
current, while convergence happens at its descending sides.
During the early history of the Earth, its interior was much
hotter (due to the greater amount of residual heat of
accumulation and the much greater amounts of radioactive
isotopes such as 235 and 40 and hence convection was much
faster and so were all the phenomena associated with it
{such as volcanic activity, earthquakes, plate movements,
mountain-building movements and continental build-ups, (or
the so- called ocean — continent cycle or the geosynclinal/
mountain — building cycle), etc}.
During these processes, both the atmosphere and the
hydrosphere of the Earth were outgassed, the continents were
constructed as positive areas above the ocean basin (through
the accretion of volcanic island arcs into sub-continents
and continents) and mountains were built.
About 500 million years ago the early continents were
dispersed across the surface of the Earth, in positions much
different than the ones occupied by the continents of today.
Convection currents then operating in the mantle ended up by
pushing all the early continents together around 200 million
years ago, into a single super-continent (Pangea) above a
single super-ocean (Panthalassa).
The outer rocky sphere of the Earth (or lithosphere) acts as
a lid, impeding heat flow from inside the Earth. The trapped
heat produced a great rift system right in the middle of the
mother continent, and this rift system propagated gradually
through time, separating North America from North Africa
(about 180 million years ago) and from Europe (about 150
million years ago), followed by separating South America
from Africa (about 110 million years ago) and separating
Greenland from Norway (about 65 million years ago), when
Iceland began forming.
When this break-up of Pangea began, a westward waterway from
the mother ocean (Panthalassa) in the form of a broad gulf
(called Tethys) encroached gradually over Pangea, breaking
it into a northern continent (Laurasia) and a southern one
(Gondwana). Further fragmentation produced the present
continental masses which are currently undergoing more
breaking up. The original rift is now the Mid-Atlantic
Ridge, whose axis is still an active site of basaltic
outpourings similar to many other rift zones along which
current sea-floor spreading is taking place (cfEl-Naggar,
Z.R., 1991, p. 42-45 and Emiliani, C., 1992: p 237, 238).
Basaltic material has been pouring out gradually from more
than 64,000 — km of mid- ocean rift valleys on both sides of
such ruptures in the Earth’s crust, since the very early
days of their formation. The youngest oceanic crust is
always around the deep rift valley and has steadily been
pushing older crusts away from it. The age of the oldest
existing oceanic crust does not exceed the Mesozoic era
(about 200 million years old), and is currently being
consumed at the convergent edges of the plates with rates
almost equivalent to the rate of producing new oceanic crust
at the mid-oceanic ridges.
Volcanic mountains are also found on the continents such as
the isolated peaks of Moutn Ararat (5l00m above sea level),
Etna (3300m), Vesuvius (1300m), Kilimanjaro (5900m) and
Kenya (5100m). These are associated with intra-cratonic,
deep rift systems that traverse the whole thickness of the
lithosphere, and communicate with the asthenosphere, and
hence are currently fragmenting the existing continents into
smaller landmasses.
From the above mentioned discussion, it becomes obvious that
the magnificent network of deep fault systems (65-150km
deep) that encircle the globe for tens of thousands of
kilometres in all directions {breaking its outer rocky zone
(the lithosphere) into major, lesser and minor plates,
microplates (or platelets), plate fragments and remnants }
is one of the most striking realities of our planet. Without
these deep fault systems the Earth could not possibly have
been inhabitable. This is simply because of the fact that it
is through such deep faults that both the atmosphere and the
hydrosphere have been outgassed and are constantly
rejuvenated, continents are steadily built and fragmented,
mountains are constructed, the crust is periodically
enriched with new minerals, lithospheric plates are moved,
the accumulating internal heat of the Earth is gradually and
steadily released and the whole dynamics of our planet are
achieved.
Consequently, such an established fact of the Earth is so
vital for its existence as well as for our own survival on
its surface that it becomes well deserving to be mentioned
in the Glorious Qur’an as one of the signs of the Creator.
However, this fact did not attract the attention of Earth
scientists until after the Second World War, and was not
fully understood until the late sixties and the early
seventies of this century. The Qur’ anic account of this
established, salient feature of the Earth more than 14
centuries ago, is one of numerous signs that clearly
testify’ to the purely Divine nature of this illustrious
Book, and to the truthfulness of the Prophethood of Mohammad
(PBUH)
by Dr. Z.R.M. EL-NAGGAR.
The Seventh International Conference on Scientific Signs in
Quran & Sunnah
* In each
of these paired numbers, the first (or the Roman Number)
indicates the number of the Qur’anic chapter (or Surah),
while the second (or the Arabic Number) indicates the number
of the Qur’anic verse or verses (Ayah or Ayat) in the Surah
(chapter).
* MYBP = Million Years Before Present |
