MORE notes from my deep reread journey of Verne books
Verne Obscura et Trivia 5-
Journey to the Surface of the Earth- compass conundrums
By Quentin R. Skrabec Ph.D.
Most readers and movie
makers focus on Verne’s descent to the earth's center, but it is the ascent to
the surface that would augur geological research. Modern geology has settled on
the molten core theory, but volcanic eruptions' exact nature and predictability
remain an active research area. Verne
was a great collector of unusual scientific phenomena related to volcanos,
which is still getting the attention of researchers. New research in seismographic detection is still dealing with some of
Verne’s observations. For example, earthquakes and tremors that almost always
precede eruptions, precise measurements of ground deformation that often
accompany the rise of magma, changes in volcanic gas emissions, and changes in
gravity and magnetic fields frozen in lava.
Let us
look at some phenomena in the ascent of Verne’s Journey to the Center
of the Earth (1864). In chapter 42, Verne describes the following types of
phenomena such as granite wall convulsions, earthquakes, jerky magma movement,
periodic lulls, heat, boiling water, superheated steam, possible electromagnetic
effects, compass spinning, sulfur, and finally, magnetic pole reversal. These
volcanic observations were not well understood in 1863. Verne ends the novel
with a research question: the mystery of pole reversal. However, the
electromagnetic effects are currently the cutting edge of research for possible
eruption prediction. Verne might not have had the answers, but he was asking
the right questions.
In
1863, there were several theories of the earth’s center and the nature of volcanos.
Most widely held at the time was that of James Hutton (1726-1803) and Charles
Lyell (1797 –1875) of a fiery core. The molten core geological theory
was accepted by most after the 1830s. 1863 French science writer Louis Figuier
(1819-1894) had popularized these theories. Verne certainly borrowed from Figuier
on the natural history of the descent (see Breyer and Butcher), but the ascent
focuses on volcanic theory and observations.
Verne
knew the latest geological theories well, but the molten center theory would
not support a literary trip to the earth’s center. Verne used an earlier theory
of Humprey Davy (1778- 1829), which allowed for a cool center and separate
volcanic eruptions by a reaction of alkali minerals, water, and solid
granite. Verne placates his more astute
readers by making Journey to the Center of the Earth a scientific and
literary debate between the cool center theory (Davy) of Professor Lindenbrock
and the fiery center theory (Lyell, etc.)) of his nephew Axel.
The
novel’s ascent combines questions, observations, and theory. Some of Verne’s
descriptions fit the 1858 published observations of Sainte-Claire Deville of
the volcanic eruptions of Stromboli (Verne’s location of the assent). Verne’s literary observations of volcanic
eruptions auger modern scientific observations and research efforts
Electromagnetic
observations of volcanic plumes have been described intermittently since at
least the time of Pliny the Younger and the 79 AD eruption of Vesuvius.
Although sometimes disregarded in the past as secondary effects, recent work
suggests that the electrical properties of volcanic plumes reveal intrinsic and
otherwise inaccessible parameters of explosive eruptions.
The
first scientific studies of electromagnetic effects, such as volcanic lightning
and magnetic bursts, were also conducted at Mount Vesuvius by Professor Luigi
Palmieri, who observed the eruptions of 1858, 1861, 1868, and 1872 from the
Vesuvius Observatory. His daring (even reckless) observations of the1861
eruption were well-read throughout Europe. In the 1800s, many anecdotal
observations of compass gyrations during volcanic activity led Palmieri to
study them at his Vesuvius Observatory.
Palmieri used an adapted Peltier electrometer
to help study magnetic and electrical fields before and during volcanic
eruptions. Twenty years after Verne’s fictional journey, at Krakatoa in 1884,
abnormal atmospheric and magnetic displays were observed, “compass needles
rotated violently, and the barometer rose and fell many tenths of an inch in a
minute.”
Such
anecdotal observations continue today. Mt.
St, Helena in 1982, a film crew was dropped by helicopter on St. Helens on May
23 (five days after its eruption) to document the destruction. Their compasses,
however, spun in circles, and they quickly became lost.
In
the 1950s, on the Mihara volcano in Japan, a major scientific study on magnetic
effects produced data on the inclination and declination of the magnetic fields. Although not diagnostic individually, these techniques,
when used in combination at well-monitored volcanoes, have resulted in
successful predictions. A successful forecast saved thousands of lives at
Pinatubo volcano (Philippines) 1991.
The USGS
Volcano Hazards Program noted in 2023 that magnetic data can be used for
low-cost volcano monitoring in various settings and environmental conditions. ( see “Volcano Monitoring With Magnetic
Measurements: A Simulation of Eruptions at Axial Seamount, Kilauea, Bardarbunga,
and Mount Saint Helens” Joseph Biasi, Maurice Tivey, Bailey Fluegel, AGU, 2022).
Scientists this decade hypothesize that it is caused by a natural geodynamo
deep within the Earth. A boiling, molten metal mixture of iron and nickel constantly
moves around a solid iron core, generating a magnetic field.
Verne’s
novel ending of finding the magnetic reversal of the compass has proved remarkably
prophetic. In 1905, a French geologist discovered a lava field with iron within
it that was magnetized in reverse. What should have been north was south. The
geologist realized this could only be possible if Earth’s magnetic poles were
reversed when the lava flowed. When it solidified, it preserved that reversed
magnetic orientation. It took another 50 years for scientists to accept that
Earth could change its polarity. In the 1970s, lava polarity was being used to
help date ancient rock. Recent research has focused on using lava to predict
and study the effects of the earth’s pole reversals. We are getting closer to
fully understanding the reversed compass ending of Journey to the Center of
the Earth.
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