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Part 1: The Solid Earth Hypothesis
    1. The standard earth model
    2. Deep drilling springs surprises
    3. Mass, density, and seismic velocity (09/05)
    4. Deep earthquakes
    5. Geomagnetism


Part 2: The Hollow Earth Hypothesis
    1. Early theories
    2. Modern theories
    3. Hollow moons
    4. Feasibility -- I (06/04)
    5. Feasibility -- II (08/05)


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Part 3: Polar Puzzles

        1. The open polar sea
        2. The north pole controversy
        3. Polar land coverup?
        4. Flights of fancy
        5. Auroras and the poles


Part 4: Mythology, Paradise, and the Inner World
    1. The Imperishable Sacred Land
    2. Shambhala
    3. A northern paradise
    4. Inner kingdoms

3. Density and seismic velocity

    If the earth's interior were homogeneous, consisting of materials with the same properties
    throughout, seismic waves would travel in a straight line at a constant velocity. In reality, waves
    reach distant seismometers sooner than they would if the earth were homogeneous, and the
    greater the distance, the greater the acceleration. This implies that the waves arriving at the
    more distant stations have been travelling faster. Since seismic waves travel not only along the
    surface but also through the body of the earth, the earth's curvature will clearly result in
    stations more distant from an earthquake focus receiving waves that have passed through
    greater depths in the earth. From this it is inferred that the velocity of seismic waves increases
    with depth, due to changes in the properties of the earth's matter.

        According to the relevant equations,* the velocity of seismic waves becomes slower, the
    denser the rocks through which they pass. Since seismic waves accelerate with depth, this
    would imply that density decreases. However, scientists are convinced that the density of the
    rocks composing the earth's interior increases with depth. To explain this discrepancy, they
    simply assume that the elastic properties change at a rate that more than compensates for the
    increase in density. As one textbook puts it:

        Since the density of the Earth increases with depth you would expect the waves to
        slow down with increasing depth. Why, then, do both P- and S-waves speed up as
        they go deeper? This can only happen because the incompressibility and rigidity of
        the Earth increase faster with depth than density increases. [1]

    Thus geophysicists simply adjust the values for rigidity and incompressibility to fit in with their
    preconceptions regarding density and velocity distribution within the earth! In other words, their
    arguments are circular.

        *P-wave velocity = square root of [(incompressibility + 4/3rigidity) divided by density]. S-wave velocity = square root of [rigidity divided by density]. In a fluid, rigidity vanishes and S waves cannot propagate at all.

        A comparison of the velocity of sound in various media shows that there is no correlation
    between sound-wave velocity and density in the case of solids and liquids [2]. Here are some
    examples involving metals:

            Substance       Density (g/cm³)    Velocity of longitudinal waves (km/s)
            aluminiu                   2.7                        6.42
            zinc                         7.1                        4.21
            iron                         7.9                        5.95
            copper                     8.9                        4.76
            nickel                      8.9                        6.04
            gold                       19.7                        3.24

    There is a correlation between density and seismic velocity in the case of gases; however, the
    velocity decreases rather than increases with density due to the increased number of collisions.

        Drilling results at the Kola borehole revealed significant heterogeneity in rock composition
    and density, seismic velocities, and other properties. Overall, rock porosity and pressure
    increased with depth, while density decreased, and seismic velocities showed no distinct trend
    [3]. In the Oberpfälz pilot hole, too, density and seismic velocity showed no distinct trend with
    increasing depth [4]. Many scientists believe that at greater depths, the presumed increase in
    pressures and temperatures will lead to greater homogeneity and that reality will approximate
    more closely to current models. But this is no more than a declaration of faith.

    4. Mass and gravity

    Scientists' conviction that density increases with depth is based on their belief that, due to the
    accumulating weight of the overlying rock, pressure must increase all the way to the earth's
    centre where it is believed to reach 3.5 million atmospheres (on the earth's surface the pressure
    is one atmosphere). They also believe that they know by how much rock density increases
    towards the earth's centre. This is because they think they have accurately determined the
    earth's mass (5.98 x 1024 kg) and therefore its average density (5.52 g/cm³). Since the
    outermost crustal rocks -- the only ones that can be sampled directly -- have a density of only
    2.75 g/cm³, it follows that deeper layers of rock must be much denser. At the centre of the
    earth, density allegedly reaches 13.5 g/cm³. All these beliefs are based on the assumption that
    the newtonian theory of gravity is correct. But there are good reasons for doubting this.

        Newton's universal law of gravitation states that the gravitational force between two bodies
    is proportional to the product of their masses and inversely proportional to the square of the
    distance between them. To calculate the gravitational force (F), their two masses (m1m2) and
    the gravitational constant (G) are multiplied together, and the result is divided by the square of
    the distance (r) between them: F = Gm1m2/r². The newtonian theory is accepted by most
    scientists today without question.

        However, it involves a contradiction. On the one hand it states that the gravitational force
    between two or more bodies is dependent on their masses, and on the other it admits that the
    gravitational acceleration of an attracted body is not dependent on its mass: if dropped
    simultaneously from a tower, and if air resistance is ignored, a tennis ball and a cannonball will
    hit the ground simultaneously. Furthermore, although gravitational force and gravitational
    acceleration are the same phenomenon, and force is proportional to acceleration,* no symbol
    for the earth's surface gravity (g) or a term for acceleration appears in the gravitational

        In the conventional approach, the above contradiction is overcome by invoking Newton's
    second law of motion, which states that the force applied to a body equals the mass of the
    body multiplied by its acceleration (F = ma); this implies that gravity pulls harder on larger
    masses. However, as several physicists, mathematicians, and philosophers have pointed out,
    this law is not based on experiment; it is an arbitrary definition -- a convention. Experiments
    cited in its support involve the identification of weight and force; they prove only that the
    weight of a body is equal to its mass times the acceleration (W = ma), and do not measure or
    define force per se [1].

        Pari Spolter has drawn attention to the fact that to deduce that gravity obeys an
    inverse-square law (i.e. that its strength diminishes by the square of the distance from the
    attracting body), Newton did not need to know the mass of the earth or moon; he needed to
    know only the acceleration due to gravity at the earth's surface, the radius of the earth, the
    orbital speed of the moon, and the distance between earth and moon. Spolter concludes that
    'there is no basis for inclusion of the term "product of the two masses (m1m2)", or for that
    matter, for inclusion of any term for mass in the equation of the gravitational force' [2].

        Spolter presents a new and simpler formula for gravitational force: F = a.A , where a is the
    acceleration and A is the area of a circle with a radius (r) equal to the semimajor axis of
    revolution of the planet, moon, etc. in question (i.e. its average distance from the body it
    orbits).* Since A = (pi)r², this equation naturally implies that the acceleration due to gravity
    declines by the square of the distance. Using this equation, Spolter shows that, contrary to what
    is implied by newtonian mechanics, the gravitational force of the sun is constant for all planets,
    asteroids, and artificial satellites orbiting the sun, and is independent of the mass of the attracted
    body. Likewise, the gravitational force of each planet is constant for any objects orbiting them
    or in free fall, regardless of their mass. The contradiction at the heart of the newtonian theory
    of gravity is therefore eliminated by Spolter's approach, since it means that neither gravitational
    force nor gravitational acceleration depends on the mass of the bodies concerned.

        *Spolter argues that force is always independent of mass [3]. It is not force that is equal to mass times acceleration, but weight. Her equation for linear force is F
        = a.d (acceleration times distance). Her equation for circular force is the one given above: F = a.A.

        The gravitational constant (G) is assigned the dimensions m³/kg.s² (volume divided by mass
    x time squared) -- a rather weird combination! Spolter believes that there is actually no such
    thing as a gravitational constant. Its value was first measured directly by the Cavendish torsion
    balance experiment in 1798. However, a Cavendish-type experiment is not a proof of Newton's
    equation: on the contrary, such experiments assume that the equation is correct. In Spolter's
    view, it has not yet been ruled out that the very small angle of deflection of the torsion balance
    used in these experiments (or the very small change in its period of oscillation) is due to
    electrostatic attraction of the metallic spheres used; in one experiment in which the small mass
    of platinum was coated with a thin layer of lacquer, consistently lower values of G were
    obtained. Spolter has written to several mainstream journals proposing further experiments to
    test this possibility, but her letters have been rejected.

        On the assumption that gravity is proportional to inert mass, the value of G can be used to
    estimate the earth's mass and average density. Spolter writes:

        About 71% of the earth's surface is covered by oceans at an average depth of 3795
        m and mean density of 1.02 g cm-3. The average thickness of the crust is 19 km and
        the mean crustal density is 2.75 g cm-3. From studies of seismic wave travel time,
        geophysicists have outlined a layered structure in the interior of the earth. There is
        no accurate way currently known of estimating the density distribution from seismic
        data alone. To come up with a mean density of 5.5, earth models assuming
        progressively higher density values for the inner zones of the earth have been
        devised. . . .
            Except for the ocean and the crust, direct measurements of the density of the
        inner layers of the earth are not available. This currently accepted Earth Model is
        inconsistent with the law of sedimentation in a centrifuge. The earth has been
        rotating for some 4.5 billion years. When it was first formed, the earth was in a
        molten state and was rotating faster than today. The highest density of matter
        should have migrated to the outer layers. Except for the inner core, which houses
        the engine, powered by a nuclear reaction and which keeps our planet rotating, the
        density of the other layers of the earth should be less than 3 g cm-3.
            Also, heavy elements are rare in the universe. How could so much of materials
        with such low stellar abundances have concentrated in the earth's interior? [4]

        In short, the mass and average density of the earth and all other celestial bodies are

        Experiments conducted over the past hundred years have contradicted important elements of
    the orthodox theory of gravity by showing that gravity can be shielded and does not have
    unlimited penetrability; that antigravity exists; and that gravity is closely coupled with electric
    and magnetic forces [5]. Rather than being a direct function of inert mass, the strength of the
    gravitational force appears to depend on the electrical and other properties of matter. The local
    gravity field on earth may vary due to the capacity of different types of rock to emit and absorb
    radiation and the ability of negatively charged particles and ions to screen out or counteract the
    attractive force of gravity.

5. Deep earthquakes

    Most earthquakes are shallow, no deeper than 20-25 km, and occur when rocks snap and
    fracture under increasing stress. Earthquakes at much greater depths pose a major challenge to
    the standard earth model because below about 60 km, the rocks should be so hot and tightly
    compacted that they become ductile; instead of breaking catastrophically under stress, they
    should deform or flow plastically. Yet 30% of earthquakes occur at depths exceeding 70 km,
    and some have been recorded as far down as 700 km. Most deep-focus earthquakes occur in
    Benioff zones; in plate-tectonic theory these deep-rooted fault zones are labelled 'subduction
    zones', where slabs of ocean lithosphere supposedly plunge into the earth's mantle (though
    there is abundant evidence contradicting this hypothesis [1]). However, some deep earthquakes
    have shaken Romania and the Hindu Kush where there are no 'subduction zones'. A variety of
    mechanisms for deep earthquakes have been proposed, but they are all controversial [2].

        The seismic radiation of deep earthquakes is similar to that of shallow earthquakes. It used
    to be said that deep-focus earthquakes were followed by fewer aftershocks than shallow ones,
    but there are indications that many of the aftershocks are simply difficult to detect, and that
    there is much more activity at such depths than is currently believed. The fact that deep
    earthquakes share many characteristics with shallow earthquakes suggests that they may be
    caused by similar mechanisms. However, most earth scientists are incapable of entertaining the
    notion that the earth could be rigid at such depths. One exception is E.A. Skobelin, who draws
    that logical conclusion that since deep-focus earthquakes cannot originate in plastic material but
    must be linked to some kind of stress in solid rock, the solid, rigid lithosphere must extend to
    depths of up to 700 km [3].

        On 8 June 1994, one of the largest deep earthquakes of the 20th century, with a magnitude
    of 8.3 on the Richter scale, exploded 640 km beneath Bolivia. It caused the whole earth to ring
    like a bell for months on end; every 20 minutes or so, the entire planet expanded and
    contracted by a minute amount. A significant feature of the Bolivian earthquake was that it
    extended horizontally across a 30- by 50-km plane within the 'subducting slab'. This
    undermines the hypothesis that such quakes are caused by olivine within the 'cold' centre of a
    slab suddenly being transformed into spinel in a runaway reaction when the temperature rises
    above 600°C. It also undermines the theory that gravity increases with depth; if this were true,
    the motion of earthquakes at such depths should be nearly vertical [4]. There appears to be
    something very wrong with scientific theories about what exists and what is happening deep
    within the earth.

        The acceleration due to gravity is 9.8 m/s² at the earth's surface and the prevailing view is
    that it rises to a maximum of 10.4 m/s² at the core-mantle boundary (2900 km), before falling
    to zero at the earth's centre. But not all earth scientists agree. Skobelin argues that the normal,
    downwardly-directed gravitational force may be replaced by a reversed, upwardly-directed
    force at depths of 2700 to 4980 km, and that the widely-accepted figure of 3500 kilobars for
    the pressure at the earth's centre, may be an order of magnitude too high [5].

        Earthquakes and volcanoes tend to concentrate along certain major fault lines in the earth's
    crust. The fact that heightened geological activity occurs along these 'plate boundaries' is
    sometimes hailed as one of the great successes of plate tectonics. However, it is precisely the
    high incidence of earthquake and volcanic activity that led geologists to label these belts as
    'plate boundaries' in the first place! Plate tectonics sheds no light on earthquakes that happen
    within plates. Officer and Page state: 'We know very little about the mechanisms involved in
    such intraplate earthquakes, but [they sometimes] illustrate effects that one might expect from a
    gigantic internal explosion, odd as such a concept may appear' [6].

        Thomas Gold has argued that, during its formation, the earth retained large quantities of
    hydrocarbons in its interior. He holds that various gases are sometimes released from depths of
    about 150 km, and when they invade the outer brittle layers of rock they weaken them by
    creating new fractures or reducing friction in existing faults, thereby causing or facilitating
    earthquakes [7]. The emission of gases (e.g. methane) from the ground is already known to
    cause mud volcanoes on land, circular pockmarks on the ocean floor, and 'ice volcanoes' or
    pingos on ice fields. Hydrocarbons and hydrogen are also major components of the gases
    emitted during major volcanic eruptions.

        Eyewitness accounts provide strong evidence that gas emissions also help to cause
    earthquakes in general, but nowadays scientists tend to ignore these 'subjective' accounts in
    favour of 'hard' seismic data. Eruptions, flames, roaring and hissing noises, sulphurous odours,
    hazes and fogs, asphyxiation, fountains of water and mud, vigorous bubbling in bodies of water
    -- all these are observed today in conjunction with earthquakes, just as they were in past. On
    the basis of such evidence, the ancients held that the movement and eruption of subterranean
    'air' (i.e. gases) caused volcanoes if they found an outlet, and otherwise generated earthquakes.
    Gold argues that this mechanism could explain deep earthquakes, since he believes that the
    mechanism of sudden rock shear cannot operate deep in the earth's interior. But as already
    noted, this belief may be wrong, and both mechanisms may apply at all depths.