1. V.V. Beloussov (1907-1990) Famous opponent of plate tectonics Structural Geologist and Geodynamicist Director of Geodynamics Dept, Inst of the Physics of the Earth Member of Soviet Academy of Sciences (appointed 1953) President of Int Union of Geodesy & Geophysics (IUGG) – 1960-1963 Vice President, International Geophysical Year committee (1956) Not a member of the Communist party but is described as a Russian Nationalist Studied the East Africa Rift and became convinced that continental regions can become oceanic regions through infiltration of mafic magma and chemical transformation of crust (oceanization) Belossov interpreted Earth history in terms of vertical movement of the crust, and proposed that oceans become more numerous with time.

2. Beloussov (1970) arguments against plate tectonics 1) Magma at mid–ocean ridges must spread irregularly, so how do you get linear, parallel magnetic anomalies? 2)Metamorphic rocks formerly buried to 3 km exposed at ridge axes 3)Old rocks have been found near mid-ocean ridges (as old as 29 Ma) 4)Marine magnetic anomalies are not uniform and thickness not proportional to anomaly age (but he doesn’t know about magnetic “skewness” due to interaction with earth’s field) 5)Sediment thickness in the oceans does not correlate with the distance from ridge 6)Magnetic anomalies are not always symmetric about the ridge axis 7)Spreading ridges do not remain stationary 8)If spreading rate changes, why aren’t there earthquakes and deformation throughout the ocean basins? 9)hotspots should move with the plates 10)There should be accretionary prisms, instead sediments are undeformed at trenches 11)If lithosphere has greater density than the asthenosphere, why doesn’t it subduct immediately? And how can low density surface rocks go down to depths > 700 km where density is much greater? 12)Geology of Iceland does not look like a spreading center 13)Plate tectonics does not match the global gravity field or heat flow data 14)Plate tectonics ignores all the basic data of continental geology – tectonic cycles of vertical motion

3. Discussion 1. How does Hess begin the paper? Why do you think he began that way? What does Hess mean by “geopoetry”? (Maggie) 2. The discoveries of the 1950s and 1960s convinced most geoscientists that continents move, whereas the evidence presented by Wegener did not. What advances were most important in producing this change? (Theresa) 3. How does Hess’ argument for continent-ocean differences compare to Wegener’s? (Amanda) 4. We have seen how broad, bold new ideas are seldom shown to be entirely correct (for example, Wegener’s motive forces and Hess’s water cycle arguments). How does the inclusion of weaker arguments with strong ones affect the acceptance of an idea? (Nils) 5. What the key evidence did Hess use to suggest that the mid-ocean ridges are spreading centers where oceanic crust is formed? (Maggie) 6. Beloussov gives many arguments about why plate tectonics is wrong. Which do you think he considered to be the strongest arguments? Which do you consider to be the strongest? (Amanda) 7. How did Beloussov’s background influence his resistance to the acceptance of plate tectonics? (Nils) 8. Would the plate tectonics revolution have occurred WITHOUT the key technological advances in the 1940s and 1950s? (everybody) 9. What social and historical developments outside science were key to the plate tectonic revolution? (everybody)