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NASA Confirms What Sputnik Indicated—The Earth Is Pulsing
By John K. Davidson, Managing Director, Predrill Stresses International

Geologists are not easily convinced by geological argument, especially when their deeply held views are challenged. Virtually no one was impressed when Snider proposed continental drift in 1858. Not surprising either, given that his key South America/Africa fit was a sketch. Wegener's plate tectonics (1915) suffered for the same reason. Although Carey started to make advances with a cartographically accurate fit in 1955, it took a non geological tool, the dating of magnetic pole reversals, and Vine's application to the oceanic seabeds (1966) for horizontal displacements to be accepted. In two years plate tectonics was almost universal!

Those displacements were thousands of kilometres. What about vertical ones of hundreds of metres? Due to rotation, the Earth is flattened from a sphere, the polar radius being approximately 21 km less than the equatorial of some 6378 km. La Caille (1751) knew it was even flatter than that, with the southern hemisphere being squatter than the northern. It was the Russian Sputniks and the O'Keefe et al. (1959) report on the USA Vanguard data that confirmed the pear-like shape, or more accurately, peach-like Earth. It is 15 m higher and lower respectively at the North and South Poles, and 7 m lower and higher respectively at the northern and southern mid latitudes.

Not much you say, but NASA's satellite ranging (SLR) data (Smith et al. 1990) show this southern bulge and northern waist are not constant. The arc distance from Simosato (Japan) across the trench to Monument Peak (California) is decreasing at 33 +/- 5 mm/year, Monument Peak across the Basin and Range and the North Atlantic Ridge to Matera (Italy) is increasing at 10 +/- 5 mm/year, and Matera back to Simosato is decreasing at 34 +/- 5 mm/year, a total decrease of 57mm/year. The southern Pacific is growing, Yarragadee (Western Australia) across the trench to Huahine (Tahiti) is decreasing at 64 +/- 8 mm/year, Huahine across the ridge to Easter Island is increasing at 194 +/- 16 mm/year and Easter Island across the trench to Arequipa (Peru) is decreasing at 62+/- 7 mm/year. This adds to 68 mm/year, or 30 mm/year if the more direct route is taken from Yarragadee to Huahine (-64) then Huahine to Arequipa (94). When either is added to the South Atlantic Ridge and to the two in the Indian Ocean, it suggests the rate of the bulge may well be greater than the waist.

The northern and southern rates would account for the 7 m aberrations from a perfect oblate spheroid in a thousand years, and if continued for a few million years, would have the Earth looking like a ship's port decanter. These oblate spheroidal departures are caused by density movements within the Earth, and must be varying or pulsing. Imagine the southern bulge was 250 m in the Late Cretaceous, the Great Artesian would have been eroded or with non marine deposits, while the equivalent northern hemisphere waist would account for the quiet deep water deposition of chalk. Climatically controlled Vail eustatic cycles may still be synchronous on subsiding continental margins, but the magnitudes of the sea level rises and falls could not be everywhere equal on the pulsing, tilted geoid.

Extensional normal faulting is not common on the continents, 'local' exceptions (white areas of figure) being the East African Rift, Lake Baikal and the Basin and Range. The continents and oceans are dominated by SH, the maximum horizontal component of the stress at a point, causing head-on compression or reverse faulting (pink areas of figure), or at an angle (strike slip). Lowering or depressing the northern mid latitudes is a flattening, or curvature reduction which causes upper crustal compression; likewise on the flanks of the southern bulge.

In 1995, I suggested 16 globally synchronous compressional pulses since the Triassic. They are identifiable on seismic reflection data, and the resulting compressional features are parallel to faults which cut the crust. These crust cutting faults do not change direction, hence it is possible to obtain, and to predict, the direction and magnitude of stresses in sedimentary basins.

The earthquake map and the SLR data clearly demonstrate plate tectonic extension (pte) of the East Pacific Rise which gives rise to subduction under the Andes and Western Pacific (ptc). Note though, that with the exception of the Indonesian subduction, a spreading rate of one third of that of the EPR results in no subduction on the continental margins adjacent to the Atlantic and Indian Ridges. This means these continents are not being pushed, they are being carried or separating due to momentum differences. Maybe momentum accounts for the second and shallower class of deep Tethyan earthquakes (ptc?). Similarly, the shallow earthquakes are of two types, extensional at the ridges and compressional (or strike slip) elsewhere on the continents and oceans (pt+). Conventional plate tectonic ridge push/slab pull is lacking, the vertical forces have been missed. The SLR identified southern bulge might be reflected in the three oceanic ridges, ie, originating in the northern hemisphere and broadening southwards, and forming triple junctions. All pulsed.

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