Harold Overton is maintaining a blog introducing his ideas regarding what might be described as cell tectonics. He refers to it as Coriolis Tectonics. It is called PorOgle and can be read here.
There are a lot of illustrative pictures in the text that I have copied and you may want to go to the blog.
What we seem to be developing is a convection cell model from deep in the earth that also manages to exhibit the effects of the Coriolis force acting on the rising fluid. These cells are huge.
I have only begun to read his material, but a couple of comments are in order. Local curvature change should induce fracture patterns that are arcs if only because the crust is curved. Also scaling will be a problem, what scale is actually relevant?
Certainly the Coriolis effect will be huge on fluid masses. This presumably describes the material of the lower crust. In fact it is reasonable to assume that crust is effectively liquid for the purpose of description after perhaps thirty miles leaving room for super cells sixty miles deep and a few hundred miles across even. Smaller ones are likely to feed of these.
We will leave it for now, but the broad existence of arcs throughout the geological record has always been obvious. This is an interesting interpretation and may be helpful. Explaining the dynamics of faulting is a good point of departure.
Coriolis Tectonics Review for Jul 09
Above and below are photos of Mt. Baker, WA- which allow this active volcano of the Cascade Mountain chain to be investigated as to how it is involved in the subduction of the Juan de Fuca portion of the original Pacific plate. This treatment shows how it rotates as it rises and how an earlier magma chamber (rotating oppositely) to the west cools and shrinks.
Review of Coriolis Tectonics and Earth Movements (July 09)
Starting with the finding that the Earth’s Crust is rotating above rising and sinking (cooling) magma chambers, this investigation is expanded to explore whether thicker Crust for protruding mountains exhibits similar behavior. The first observation was that results are exaggerated in the Equatorial bulge zone (about 40N to 50S Latitudes), because of the thicker Crust, compared to that at larger Latitudes.
Examination of slickensides and sheared concrete slabs indicates that rising magma crust rotates CCW, whereas cooling Crust exhibits CW rotation. This was documented for youthful volcanoes in southern Utah (200 kyears), to show the sensitivity of this movement to time intervals.
Above is shown the rotating and cooling cell along Hf, near Hurricane UT.
The Colorado Plateau (review this from previous blogs) The transition zone, off the edge of CP, has numerous volcanoes and rotating cells for each, and also exhibits CW rotation along Hf (on the west side of Hf) and the Wasatch Line (separating CP from B&R). The Rocky Mountains appears to exhibit a similar phenomenon, with rotating cells occurring along the line of protruding blocks. These are more complicated, but again result in circular river valleys and a tilt of sink to mountain uplift across the cell diameters.
All of this analysis may be checked against the GPS vectors for the Whole Earth, using the above photo as a reference (this shows the movement of the Crust at particular stations, over a short time interval.
All volcanoes investigated (Grass Valley, Hackberry, AZ, Mt. Baker, Mt St. Helens, and Rainier, WA) showed a circular pattern of river drainage about them. This behavior is sensitive to the Latitude of location, so that those near the Equator do not indicate Coriolis rotation or circular river valleys (Indonesia and Equatorial Africa- Kilimanjaro). The HI islands near 20N Latitude do show rotation, obeying similar rules as those at greater latitudes. Arenal in Costa Rica at 10N is marginal for circular river patterns. The velocity of spinning earth at the equator is maximum, and the surface velocity becomes smaller, the further a particle of mass lies north or south of this line. Consequently, significant Coriolis rotation is noticed after Latitude of 10N or south is exceeded.
The lateral rate of movement was found to be 5 mm/year or less for cooling and shrinking volcanoes, but the preliminary evidence for actively rising magma is that larger rates occur. The reversal of rotation, upon exhaustion of the thermal expansion, can produce reversal of faulting- e.g. thrusting becoming normal faulting for the same fault plane as cooling ensues. This has not been documented, although reversal does occur (investigated by me) off the flanks of Woodchute and Wilson Mountains in AZ.
The rotation exhibits shear of the rocks at the margins of the Coriolis cells, in arcuate drainages surrounding the cells. This produces slickensides and curved canyons which easily can be seen on the Google Earth map. Occasionally there occur hot springs, which evidently result from active shear of the boundary rocks.
Below is shown the island of Cuba, surrounding a scarp on the south side, which has the Cayman Island at the center of the diameter of a Coriolis cell. Although Cuba has been influenced by lateral movement from the Yucatan strike, it still shows all the significant features of the cells found in the SW USA.
The cell is recognized, by finding a Reactionary Cell, off the NE coast of Cuba. You can see the rotation as the offshore Crust is dragged along by the main island mass (Coriolis forces work more strongly on protruding mass which is moving under a separate impetus, although there is undoubtedly a force acting on seabed which protrudes also). There is another cell to the NE of this one, but one is sufficient to see that Coriolis forces are at work- dragging the sea bottom along with the movement of the island. A caveat exists: Cuba was evidently arrested in its development of the cell- possibly by the Yucatan strike- terminating the southern portrait before it can be recognized. The known Geology of Cuba should now be incorporated, to reinforce or deny this presentation.
Incidently, this type of RC has been documented for the Valley of Fire great lateral faullting in NV, for the south part of the Grass Valley rotation, and for parts of the Rocky Mountains.
For UT and the young vulcanism near the AZ border, there occurs a centerline feature, which cuts the cell through its center- the Hurricane fault, Hf, near Hurricane, Utah. The scarp exhibits three divisions: a relatively non-rotating center third, a gradually velocity-increasing rotating outer third, and an opposite third which contains a geological feature exhibiting compression or extension according to the half of the cell which has the greater thickness. The case of Grass Valley, UT showed a sink on the slower-moving side (Laverkin) and a monocline on the faster-moving side. This is interpreted as due to the elevated (thicker Crust) side of Hurricane fault, Hf moving faster and shoving the monocline by compression, while the opposite side exhibits a lag of movement for the thinner Crust in Hurricane Valley. This general feature produces a Mogollon Rim partition in AZ, and the Wasatch Line, UT for larger rotary cells.
Above is the first Coriolis cell investigated (the Hurricane, UT Grass Valley "Discovery rotary cell"). It is the feature to be used for subsequent analyses- which have proved to be similar in many respects.
These findings will be documented further for vulcanism, and are also being tested for protruding fault blocks and the Rocky Mountains. The findings appear to be duplicated for these cases, but the interpretation is more difficult- what with additional tectonics- other than thermal extrusions- being involved. For these cases, the centerline entity does not always occur.
Coriolis cells near Hungry Horse, MT, in the Rocky Mts. are noted by circular river valleys.
These Coriolis rotating cells are so omni-present for the continents, that it appears that the Tectonic plate theory is not appropriate to use as a paradigm for movements and geothermal events inland from the subduction (Vulcanism) or collision zone. Rather than orthogonal blocks of Crust, under continents there occur rotating cells, which create shallow metamorphism, heat of friction, and lateral faulting. The proof of this may be determined by inspecting horizontal slickensides at the cell extremity, lateral fractures and faulting in concrete slabs, and circular stream patterns about active features. River valleys are seen to be dragged along the direction of rotation, at the outer edge of the cells. Salt domes, volcanoes, protruding fault blocks, and whole islands are seen to rotate CCW in the northern hemisphere, due to this mechanism. Conversely, sinking entities- such as sinks, depressions, and subsiding basins- rotate CW, again producing heat in springs, and about contiguous cells rotating in similar directions.
The Whitefish and Flathead River region is shown above- where there is a Coriolis cell, partly defined by river valleys and partly by traces in the mountain valleys. Note that it is in a region noted by thrusting traces NW-SE, which have the top plate on the west side. There is also some reversal of thrusting direction which will be portrayed in a separate photo.
Above photo is my interporetation of the interaction of thrust faulting and the Rocky Mt. trench with Coriolis rotation. The cell is a reactionary feature which reacts to the movement along the fault system- creating a rotation between two linear traces of faulting. The direction of rotation and extent of the cell will have to be located in the field with slickensides, anomalous fractures in rocks, or with any concrete slabs which are in the path of the exhibited trace.
Above photo is speculation, based on other rotating cells found in western USA. It shows how a larger movement creates the shear zone in which the Rocky Mt. trench is located. If correct, it would initiate the movement necessary for Coriolis forces to move the cell CW (sinking vertically, the opposite of those found for rising areas).
This mechanism results in large plates being influenced by Coriolis forces, upon approach to continents- on the shelves, so that the edges are rotated away from the main plate. In the process, smaller segments are produced, as they rotate and shear away from the larger plate. These smaller plates are no longer dominated by the main plate and become rotating cells, with different motions. An example is that of the large rotating boundary known as the CA NW-SE coastal fault system, which is seen to immediately become parallel to latitude lines upon entering the continental shelf.
Expanding this region, which is vital to understanding the transition from Plate tectonics to Coriolis rotation on continents, look at the following photos:
Expanding even further, below, smaller separation gridlines are found on the north side of the 40N parallel. These have 6 nm spacing (compared to 16 nm on the south side and for HI-E south side), and are on the faster-moving part of the entity (the north side has the continental shelf further to the east than the south side). This is another clue to the evolution of the grids, where faster formation develops closer arrangement of grids. Incidentally, the RIFT or spreading center lies on the north side also. This hints that velocity is connected with thermal activity (such as with HI-E seamount chain), and with heat of development-friction of moving plates against each other.
The grids located just below the 40N transform are similar to those found offshore Las Angeles and below Hawaii big island, in that they have a 16 nm separation, and in this case are parallel to the 41 m.y. Kimmei seamount transform.
The influence of the NA continental land mass is shown in the above photo- where the shelf has great influence on the rotation of a part of the Pacific plate. There is a rotation away from the positioning and orientation of the larger basin plate.
These are all active according to the tectonics known for the particular regions where they are located (faulting, vulcanism, or transition-shearing). Notice that we have a new presentation for the 40N case- in that the west side of one of the grid lines is terminated and is diagonal to the grid line (this is similar to that for the central Pacific,-but contrasting angle of presentation- for HI).
This 40N transform (Mendocino) may be viewed at the Kimmei (found there at 32N Latitude- note naming error on photo) seamount location, to find the effect that a major inflection has upon the shear orientation exhibited with gridlines in the North Pacific Ocean. This is a major clue to the events transpiring south of the HI big island (Loihi and further south), as to the incipience of the shear producing the gridlines and possibly the heat of friction- creating VULCANISM?
Notice the linear gridlines, orienting at multiples of 60 degrees. North of Kimmei, the lines trend SE, and later NE (rounding off the odd 15 degrees). This correlates with the change of direction of the major movement of the blocks of Crust, above and below the Kemmei seamount. In other words, a relative change of movement produces two diagonals with 60 degrees separation.
The oceanic shear anomalies are a large enough sample to state some similarities:
1. All of the examples occur near major disruptions to the Ocean Basin, with a proximity to a land mass;
2. There is indication of shear between Coriolis rotation and the Pacific plate;
3. The 16 nautical-mile-spaced gridlines are parallel to some larger trace, e.g. the 40N
transform near Mendoccino, the E-W fault system and offshore islands near Las Angeles, and the anomalous spiral along the Aleutian chain; and,
4. The gridlines appear similar to fractures, in that they do NOT cause significant lateral displacement of older transforms or basin traces.
THE MAIN CONCLUSION SO FAR IS THAT HI-E IS CREATED BY SHEAR OF THE OCEAN BASIN- CREATING HEAT. HOWEVER, THERE IS NO INDICATION AS TO WHAT CREATES THE ANOMALOUS SHEAR- OTHER THAN IT IS IN THE CENTRAL PACIFIC, WHERE A MECHANICAL RESONANCE OR OTHER HEAT-PRODUCING ENTITY RESIDES (MORE OR LESS PERMANENTLY, SINCE THE MESOZOIC- only disrupted in linear presentation by meteor or asteroid strikes).
Now view a coastal Mendocino feature and expand the coastal location, so that anomalies may be located:
Mendocino, CA is the "coasting out" point, where the NW-SE fault system orients gradually E-W (lookig westward) over the continental shelf- along the 40N Latitude line.
Notice in the Google photo below that the 40N transform influences the grid pattern and the rotation of surrounding seabotttom. This is a major clue to the formation of the grid lines and how a linear feature is surrounded hy Coriolis rotation. We will use this conclusion for the interpretation of the HI-E chain, and try to determine what causes the HI chain to orient consistently in a diffferent direction (N120E).
The "Big Picture" of shear versus Coriolis rotation may be noticed along the East Pacific coastline above, as indentations of the coastline or as protrusions (Heads or Points), so that the relative shear movements may be extrapolated into the Pacific Basin floor. These transforms and relative movements are almost unique for the Central Pacific basin, hinting that the North pacific is peculiar in this respect, compared to other ocean basins
Photos below introduce another feature which is related to Coriolis Forces:
Formation of Tombolos by Coriolis rotation:
On Whidbey Island, WA, there is a tombolo and spit attached to the coast near Polnell and Mariner's Cove. This feature lies between two faults investigated by USGS in P.P. 1643, which are left lateral faults continuing to Camano Island to the SE. The entire interpretation is shown on the above two photos.
These are young cells < 50k years of age, since they are entirely developed in glacial till and silted bays derived from influx from glacial input and volcanic ash.
Although USGS has inferred the underwater faulting and indicated that the faulting is normal, most large fault systems on W.I. are left-lateral, as found by my investigation of slab shearing and rock movement.
I have found from investigation of the Valley of Fire, NV lateral faulting, that two contiguous lateral faults will drag the intervening rocks to form a circular cell. I name this a reactionary cell, RC. It rotates accordng to the twist of the rocks between the two contravening actions.
The large fracture which is a part of the standard arrangement of a coriolis cell (derived by the centerline-related tilting of the cell) is shown below:
Since the cell is formed by rotation of rock about a central feature, it develops (or is determined by) a scarp or linear feature in the center- about which the circular feature is inscribed.
Below is a photo of the outlet for Pah Tempe hot spriings, Hurricane, UT, which issues from the edge of the Virgin river. This spring has a lot of information published for it, since it was a commercial unit disturbed by the placement of a dam on the river. It has a high concentration of bicarbonate dissolved in it, because of the water passing through the Palezooic limestones. Downstream, the bicarbonate precipitates, forming unusual cementation of river gravels (forming a pre-historic dam which created meanders on the river channel.