Diamond Pipe Pipe and dyke structures on Earth appear as kimberlite deposits in every continent (see Fig-Diamond Pipe). They are all located on Precambrian shield belts (but penetrate some younger sequences), and are unique in that no similar vents have developed recently. They apparently formed under tectonic conditions not currently existing on Earth. Diamond deposits show that carbon existed in Kinetic Pipes at around 200km depth, where the pressure and temperature are sufficient to form diamonds. Carbon may be drawn from the surface into the sinkhole structures or injected igneously into the column during the down casting cycle.

Quiescent vents on Earth today are kimberlite, or similar pipes. Diamond formation, associated with these pipes, required burial depths around 200 km where pressures reach 100,000 atmospheres. The superheated steam released in Archaean times, when lifting material from 200 km below the surface, was sufficient to accelerate particles over Earth's escape velocity of 11.2 km/sec.

Much of the ejected material from Kinetic Pipes can reach and exceed planet orbiting speeds. Silica rich meteorites originate from Kinetic Pipe activity, while iron rich asteroids are more likely to come from Eye spot vents. Kinetic Pipe material forms the classic ice and rock ring structures surrounding Saturn, and is possibly the origin for some low density smaller satellites. Ice and/or rock rings are present, to a waning extent at other outer giant planets. This implies that these ejection mechanisms have universal application with planets of Super Critical Mass. This Vortex stage of activity on Earth peaked over one billion years from -3500my to -2550my. Kinetic Pipe activity continued much longer, but at a considerably reduced level.


kinetic pipe This essay proposes a sink hole, drawn into the underlying plastic rock material by downwards convecting, whirl-pooling, magma flows, forms a Kinetic Pipe (see Fig-Kinetic Pipe.)

The depression below the overlying crustal or sedimentary rocks becomes geotechnically unstable. Overlying rocks collapse into the void, forming "mass cave" structures. The void continues to depress and fill with collapsed roof, runoff and ground water, carbonaceous material (new or old), and wall rock. Water pressure and detritus effectively support the steep sided walls as the pipe draws ever deeper. Depth increases to where temperature and pressure is sufficient to convert carbon into diamond. This column of material is very unstable. Any mechanism that causes the column to rise, results in the release of ever increasing amounts of energy. The release of energy only stops after the vent ejects all the superheated material. Two possible mechanisms could cause column instability including: 

a) When the convecting magma vortex eventually breaks off the underlying crustal blobs, or its vortex action diminishes; an isostatic adjustment occurs. It allows the crustal layers over a localised area to float back to a higher elevation. The reduced pressure on the superheated volatiles filling the pipe, causes a massive and gathering release of energy. Surface meltdown existed on Earth for the first 700 million years (-4550my to -3800my), before a proto continent started to form. Magma elutriation processes occurred, as with other Super Critical Mass planets which lets lighter silica, aluminium, and magnesium rich materials form a scum on the molten surface. Lava scum collects near the Vortex. As temperatures reduce, the raft becomes more permanent. Radial compressive forces (Kinetic Pipe. - G'&G") from the incoming magma, build a thick highly folded, continental core (D). A plastic raft of thinner material surrounds the thick core. Downwards flowing magma forms vortices under the plastic raft and progressively entrains some underlying surface, creating pendants (ABC). While the pendants grow longer a central void forms, and "Block Caving" occurs in the overlying brittle rocks. The central void fills with liquid, mud, and boulders. This forms a viscous hot mixture with little convection flow. The fluid mass heats and reaches high confining pressures as the depth of burial increases. Eventually a plastic blob (F) pulls away from the underside, and an isostatic release of the overlying layers occurs. The high temperature brew suddenly reacts, at lesser burial depths, to much lower confining pressures. It forms into superheated steam. Rock and fluid contents explosively eject (E) into the atmosphere, and sometimes tear the surface to form dyke structures radiating from the vent. Rock fragments become highly sheared due to their exploding moisture contents and the kinetic release of energy.

b) A long period of hot climate following a relatively cool period will cause the upper levels of the vent to heat, expand, overflow, and reduce in density. This lowers the pressure on the column and initiates converting potential energy into kinetic energy. This mechanism may explain the recently noted violent rising storms in the northern cloud patterns on Saturn (see Fig Saturn) and places Saturn at the Projectile Stage of dynamic development. These followed an extended period with the northern hemisphere pointing towards the Sun.(Ref: Geoff McNamara, Southern Astronomy, Planetary Page 52, Jan/Feb 1991: quote) "Just what the GWS (Great White Spot) is not fully understood. Saturn's normally 'calm' appearance is now considered to be the result of a high layer of aerosols (small solid particles) and haze (liquid drops) obscuring the lower atmosphere. The five large spots observed during the past 200 years have occurred with puzzling regularity - in 1876, 1903, 1933, 1960 and now 1990. This coincides with the time of mid-summer in Saturn's northern hemisphere."

A violent ejection of the pipe contents occurs when superheated steam (geyser), jets detritus high into the atmosphere. Entrained rock fragments massively shear to the point where they form a characteristic kimberlite material. Wall rocks tear from the pipe wall, and may come to rest at a higher elevation, or eject completely from the vent. Diamond bearing material, if present, can return to a near surface location, or exit the pipe completely. Subsequent weathering will produce the various known diamondiferous deposits. At the time of ejection, Si-rich projectiles may form orbiting rings around the planet. Alternatively they may return to the surface as showers of tektites immediately, or in the future.
Refer also

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