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Dr. Giancarlo Scalera
local time: 2024-07-01 07:19 (+01:00 )
Dr. Giancarlo Scalera (Abstracts)
Titles Abstracts Details
  • The Expanding Earth: A Sound Idea for the New Millenium (2008) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    Source? A short review of the more relevant modern arguments in favour of the conception of the Earth in expansion is provided. The advantage of the expanding planet idea is a common explanation of several outstanding problems coming from palaeontology, palaeomagnetism, geology and climatology. All these problems should be regarded as be a sort of distortion effects, which arise if we try to reconstruct the situation of old geologic times adopting the modern Earth's radius ? the distortions become larger and larger as we came back in time. As a consequence the expanding Earth could be considered a natural generalization of the plate tectonic. A strong support to this generalization came from the simple and united explanation that can be found in the expanding Earth of the classical geodynamic phenomena of the polar motion and the true polar wander by an inversion of the paleogeographic position of the triple points. The conviction is expressed that basic information about this old global tectonic conception should be provided in secondary school and university courses.


  • Is Large Scale Subduction Made Unlikely By The Mediterranean Deep Seismicity? (2008) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    The deep seismicity in the Mediterranean region does not have the pattern that the alleged convergence of Africa and Eurasia should produce. Often, where subduction slabs and Wadati-Benioff zones should be present ? showing intermediate and deep hypocenters ? only shallow intracrustal seismicity is detected. Most geoscientists admit, without a valid explanation, that in this region subduction occurs largely aseismically.

    Inspection of South Tyrrhenian, Aegean and South Carpathian deep foci zones makes clear that these isolated narrow plumes (or clusters, filaments) of hypocentres cannot be sites of active subduction but that they are related to uplift of deep mantle material. Their presence under actively rising part of orogens ? besides many additional clues coming from a number of different fields ?leads to a unified interpretation of the involved phenomena, and to a new interpretation of the orogenic processes and fold belt building. The evidence points to vertical displacements of materials as the main process responsible for deep earthquakes, volcanic phenomena and orogenesis.

    Several tens of km of overthrusts and underthrusts should not be mistaken for large-scale subduction, and the limit of 50-70 km (the roots of an orogen) should be considered the maximum depth of occurrence of metamorphism. Into these limits of depth, the nonlithostatic overpressures due to the surfaceward mantle flow, the association of fluids, extreme magnitude earthquakes and deviatoric stress can be the causes both of those metamorphosed facies (until now presumed to come from depth up to 200 km) and of a shallower than supposed synthesis of biogenic and abiogenic hydrocarbons.


  • Great And Old Earthquakes Against Great And Old Paradigms ? Paradoxes, Historical Roots, Alternative Answers (2008) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    The similarity of the vertical displacements shown by case-history extreme-magnitude earthquakes are scrutinised (Chile 1960, Alaska 1964, Sumatra 2004, . . . ). A common interpretation ? an uprising of lithospheric material ? can be found, which is supported by the irregularities of the hypocentres distribution along the Wadati-Benioff zones. In the case of major South American earthquakes, a volcanic eruptions-earthquakes correlation is recognisable. Further support to this interpretation is the displacement of the Earth's instantaneous rotation pole ? 3.0 mas (10 cm), observed at ASI of Matera, Italy ? the seismic data (USGS)in the two days following the main shock, the geomorphologic data, and the satellite data of uplift/subsidence of the coasts (IGG) make possible a new interpretation of the Great Sumatran earthquake (26 December 2004) based on the second conjugate ? nearly vertical ? CMT fault plane solution. All this converges toward different causes of seismogenetic processes, strongly supporting a deep origin of disturbances, fluxes of materials leading to more or less sudden movements of masses, and phase changes, which lead to either earthquakes or silent-slow events in Wadati-Benioff zones. A reinterpretation of the geodynamics of the active margins and mountain building is proposed with a heuristic model that does not resort to large-scale subduction, but only to isostatic uplift of deep material intruding between two decoupling plates in a tensional environment. Concomitant phase changes toward less-packed lattice and buoyancy effect caused by the Clapeyron slope can help the extrusion of material over the m.s.l., constituting an orogenic process. The phenomena expected to occur in the model directly and harmoniously contribute to the building up of the surface geophysical and geomorphological features of the orogenic zones.


  • Fossils, frogs, floating islands and expanding Earth in changing-radius cartography (2007) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    In this short note I have tried to make clear the issues surrounding a recent discussion on changing-radius paleo-
    biogeographical problems of the Pacific Ocean biotic distribution. It is stressed that such an important discussion
    cannot be developed in the absence of proper cartographic methods that must necessarily introduce an increasing
    radius parameter, highlighting the effects of a changing curvature in the continental/oceanic plates in their move-
    ments from a globe of a given radius to a new position on a globe of different radius. Many other aspects of pale-
    ogeography,paleomagnetism,paleoclimate can be faced in a new and more open-mind philosophy and considered
    in a legitimate additional degree of freedom:globe size increasing. The new increasing-radius Cartography can be-
    come of fundamental importance for the advancement of science ? not only of Earth sciences.


  • Are Artificial Satellites Orbits Influenced by an Expanding Earth? (2006) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    The possible role played by parameters linked to the expanding Earth on the effects we observe in the orbital mo-
    tion of the artificial satellites is discussed here. The important result in this short note is the discrimination be-
    tween the reality of the glacial rebound process and/or the relaxation of the 100 m excess of equatorial bulge tes-
    tified by the high rate of , and the improbable role that glacial rebound can have in driving PM and TPW. It is
    recommended that the new technology of drag-free satellites be used (Gravity-Probe B is the first step) to reveal
    possible residual orbital parameter variations ascribable to formerly unrecognized fictitious drag terms due to
    Earth radial increase. J2o


  • Are subduction zones actually mantle wedges upduction? ? A new interpretation of the Mediterranean arcs (2005) [Updated 7 years ago]
    by Giancarlo Scalera   read the paper:

    Recent reviews of results of different group working to large scale seis-
    mic tomography show that the prolongation of the rigid/colder lithospheric slab up
    to the core mantle boundary, if any, is not clearly recognizable (Fukao et al., 2001;
    Romanowitz, 2003). Often the tomographic images of these high-velocity bodies
    smoothly become horizontal ? at the deep of the 640 km discontinuity ? and often
    they continue to bend slightly coming back toward the upper mantle.
    Because the strict similarity of some Italian and Mediterranean tectonic situations to
    the East Asia tectonics ? arcs, trenches, Wadati-Benioff zones, volcanic and seismic
    activities, and the above mentioned horizontal bending of the alleged lithospheric slab
    ?, many clues are examined in search of new interpretations of the Mediterranean ge-
    ological and observational evidence, with the aim to find solutions that are exportable
    to the problems of the circumpacific arc-trench zones.
    The inspection of facts coming from surface geology, magmatism, geochemistry, dif-
    ferent method tomographies, etc., is at variance with the alleged Africa-Eurasia con-
    vergence. The clues for rifting prevail on those for compression, and many tectonic
    situations previously interpreted as due to plates? collision, are associated or mixed
    to rifting evidence. The high velocity bodies characterizing the Wadati-Benioff zone
    connects gently with large extents of anomalous high velocity mantle trapped in the
    transition zone. Consequently the proposal is put forward that limitate amount of up-
    rising ? or upduction ? of mantle material wedges ? driven by isostasy ? between two
    separating lithospheric plates could be a new work hypothesis (Scalera, 2004a,b).
    Because on an expanding Earth the Mediterranean region has had ever a little lat-
    itudinal extension, it is possible in this view, to identify as Mediterranean phases of
    opening also the Paleo Tethys and Neo Tethys currently alleged ?closures?, which have
    added to the Proterozoic nuclei the Variscan and Alpine terranes respectively. These
    phases and their orogens has to be considered as extensional phases ? in which con-
    tinentalisations of narrow basins have happened ? and the added terranes of African
    provenance (e.g. the Adriatic fragment) should be regarded as fragments left behind
    by the going away continental Africa. In this sense, considering the ongoing process
    of opening as having Proterozoic origin, it is possible to speak of the Mediterranean
    as a slowly nascent ocean, but also ? paradoxically ? as a very old ocean.
    More generally, this way of reasoning could be extended to Middle East paleo-
    tectonics and to Asia (Scalera, 2001), checking that the greater proximity of Eurasia
    and Gondwana on a smaller globe obtainable in the expanding Earth framework can
    resolve many of the outstanding problems of paleogeography.
    Future aim of this research line is to better describe the different phases of opening
    of the several Mediterranean basins, taking into account the older age of eastern Lev-
    antine seafloor, the intermediate age of western Mediterranean and the young age of
    the Tyrrhenian sea, all in a framework in which Africa is slowly escaping away from
    Europe.


  • Criticisms of the Subduction Concept (2005) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    Some strong criticisms of subduction by a prominent geologist from Italy.  This is a powerpoint presentation converted to a pdf file.


  • Earth's Rotation, Shape and Gravity (2003) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    Meeting held in Nice, France, 6 - 11 April 2003. The expanding Earth view is adopted, with the aim to show the links Earth's rotation, time-varying gravity, expansion, can present in shaping our planet. An increasing gravity - whatever the reason may be - must induce an additional J2 variation, towards a decreasing ellipticity. The same effect, in different magnitude order, could be produced by the slow decay of the well know equatorial ca. 100 m. excess flatness of the Earth - due probably to a faster paleo-spin. The combination of these two effects can cause both misinterpretation of some phenomena like the alleged glacial-rebound, and difficulty to recognise the probably small amount (few mm/yr or fraction of mm/yr) of Recent global expansion. The need for a varying Earth's gravity is envisaged as a consequence of an expanding Earth due to cosmological causes, having some signatures in geological records and astrophysical large-scale structure dynamics. Finally the expansion of the Earth - and then an increasing gravity - finds a new support in the forecast of an oscillating path of the True Polar Wander, which has been already observed.


  • Ott Christoph Hilgenberg in twentieth-century geophysics (2003) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    The main points of the life and scientific production of Ott
    Christoph Hilgenberg (1896-1976) have been reconstructed. The
    events took place between America and Berlin: in America from
    1925 to 1928 the young Hilgenberg, with a diploma in Mechanical
    Engineering, worked as a Geophysicist in an oil prospecting
    company. It was there that he probably developed his interdisciplinary
    ideas, which, influenced in various ways by the European
    cultural climate, brought him into the field of global tectonics. He
    conceived a theory about the expansion of the Earth based on the
    nature of the gravity field. In 1933, the theory was published in
    his classic work Vom wachsenden Erdball. Upon his return in
    Germany he performed various types of research at the School of
    Engineering, then that of Geology and Paleontology at the
    Technical University of Berlin. He was also briefly involved as
    editor of the scientific publications at the Technical University of
    Berlin, where he made a contribution towards saving the book
    collection as the war ended. During the years spent in Berlin, he
    continued to refine his elegant version of the theory of Earth’s
    expansion publishing articles and books on this subject up to the
    last years in his life. The importance of Hilgenberg lies in the fact
    that he marks the beginning of the integration of various scientific
    disciplines from Physics to Paleontology and Paleomagnetism, in
    support of a universal tectonic theory, and that he made paleogeographic
    reconstructions on globes with smaller radii than the present
    one. All those who have worked or are working with one of
    the versions of expansion tectonics owe him enormous gratitude
    for his inspiration and for the scientific and moral lesson of fifty
    years spent in unflagging defence of his ideas. The material gathered
    and kindly made available by his daughter Helge has been
    indispensable for this recalling.


  • Releaions Among Expanding earth, TPW, and Polar Motion (2001) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    The possibility of a link between asymmetrical Earth?s expansion and Polar Motions is
    investigated, searching for possible mechanisms of inner and/or surface material displacement, which
    can lead to the observed Chandler Wobble (CW; eulerian free oscillation) and its secular drift. While a
    main result of this work is the individuation of the possible cause of PM in the diffuse emplacement of
    new mass in and under the triple point zones, the problem of the continuous excitation of the CW is
    still not resolved, and only a qualitative argument is proposed. The result is found that the PM?s actual
    parameters can be prolonged in the geological past, reproducing with satisfactory approximation the
    more reliable True Polar Wander path up to 100 Ma, and its slowing down and inversion of walk
    around 50 Ma.


  • The Global Paleogeographical Reconstruction of the Triassic and the Paleoposiont of India (1999) [Updated 7 years ago]
    by Giancarlo Scalera   read the paper:

    Following the production of a series of three paleogeographical reconstructions for the Paleocene, Cretaceous and Jurassic, a further reconstruction has been made here for the Triassic period, with the assistance of paleomagnetic data. The data provided by mutual fragment positions and paleomagnetic vectors, are best reconciled if the data is treated in an expanding Earth framework, and gives credence to the view that this represents the real evolution of the Earth. In particular a new solution of the case of Indian paleoposition is given which could constitute the key to the reinterpretation of the Eurasia paleogeography throughout geological time.


  • Paleogeographic Reconstructions of Compatible with Earth Dilatation (1998) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    Annali di Geofisica, V41, N5-6, pp. 819-825 (Nov/Dec 1998). The preset research concerns the study of the possiblity of an increase in the size of the Earth because of a still unknown process. After a previous recognition of the existence in the Pacifi of chape conformities in a number of pairs of continental and oceanic boundaries (Scalera, 1991, 1993a), a search for compatibility of these results with in dependent data sets, paelomagnetic and geological and paleontolgocial was undertaken. The conclusion is that the Earth's dilatation is compatible with the used data, while nothing can be affirmed with certainty about the dilatation process of it continunity or discontinuity through geological time. A tentative model of the evolution of the trench-ar-backar systems has been provided, tuning it in agreement with a dilatational planet.


  • Earth Complexity vs. Plate Tectonic Simplicity (1994) [Updated 1 decade ago]

    A strong impulse to the geosciences was due to the journey of Christopher Columbus and to the subsequent work of contemporary cartographers in mapping the new continents. The similarity of the Atlantic coastline shapes of South America and Africa become immediately evident, transporting the 16th century thought towards new "continents" of ideas and awarenesses. From the sometimes different and attenuated flat Earth dogmas (Randles, 1980) defended by the church in the age of Columbus, three centuries were needed to slowly develop the links with other fields which prompted the French naturalist Buffon to affirm that:

    They (elephants, rhinoceroses, hippopotamuses) lived contemporaneusly in the northern region of Europe, Asia and America; a fact revealing that the two continents were once contiguous and that they separated in later epochs. (......) Maybe the separation of Europe from America happened 10,000 years ago.

     


  • Relocation of Paleopoles on Variable Radius Earth Models (1993) [Updated 1 decade ago]

  • Palaeopoles on an Expanding Earth: A Comparison Between Synthetic and Real Data Sets (1989) [Updated 1 decade ago]
    by Giancarlo Scalera   read the paper:

    Using an ad absurdum reasoning applied to synthetic plates and associated palaeopoles it is possible to prove that if the Earth's radius during the Early Cambrian had been half its present size, palaeopoles of the continents, or of their particular sub-sets, should show typical patterns. These effects, due to the variable curvature of the Earth's surface, suggest possible tests on the real situation using the available palaeomagnetic data. If such effects could be detected on the real Earth they could constitute a new clue favouring the hypothesis of an expanding Earth. The results of applying palaeopoles and ocean-floor magnetic anomaly boundary conditions to palaeogeographical reconstructions for a variable-radius Earth are presented, taking into consideration the real continental shapes.