* There doesn't seem to be much ejecta around any of those craters, so they may have formed electrically, or the ejecta were blown away or melted into the terrain. Or the terrain is so tight, that ejecta isn't produced. * The last image seems to be two craters in one. The first image looks most like an impact from an oblique angle, but it's missing ejecta, I think. * The Carolina Bays are among the best examples of elongated craters on Earth, though I heard there are similar ones in other parts of Earth.
Lloyd
Re: Help Us Explain Crater Formation!
Crater Experiment Image * Here's an image from an old crater experiment video that someone sent me today. I think he told me before that the experiment involved shooting a bullet into some material, to see if it conformed to normal craters. But he hasn't provided any more details yet. I'm hoping he will reply soon. * The rim seems to be raised as in normal craters. And there may be scalloping on the right part of the rim. It even seems to be a bit hexagonal. I think high velocity impacts may produce electrical effects, by partial ionization via air friction and friction of the impact. * I also just found this image on the internet. * A 10-cm-sized laboratory hypervelocity impact crater - sciencemag.org
Lloyd
Re: Help Us Explain Crater Formation!
Conventional Crater Formation Theory * This is for reference. It comes from http://www.mnh.si.edu/earth/text/5_3_2_0.html. In and Around the Crater - The compressed rocks rebound immediately, causing an explosion that blasts out huge quantities of material. Much of this debris falls back to Earth around and in the crater. - The shock wave pulverizes surrounding rock, and the incredible pressure creates distinctive new minerals. - In a hypervelocity collision, the heat is so intense that it completely melts rocks at and near the point of impact. That molten rock turns solid again and becomes glass. Beneath the Crater - The shock wave also generates distinctive fracture patterns known as shattercones beneath the crater. The cones point toward the impact site and are mainly visible in deeply eroded Earth craters. - When the melt turns solid again, it forms a black rock called pseudotachylite. - The intense shock wave radiating from the point of impact crushes the rock below the crater and generates friction between the broken fragments. This friction melts part of the rock. Far From the Crater - Some large impacts squirt molten droplets of target rock into the atmosphere—and sometimes even above it. These droplets can land thousands of kilometers from the impact site, sprinkling vast areas of the Earth, known as strewn fields, with chunks of glass called tektites. Microtektites—much smaller bits of glass—shower even larger areas. - Giant layered tektites fall near impact site. - Splash-form tektites have droplet or splash-droplet shapes. - Flanged tektites shoot above atmosphere and remelt at reentry, taking on aerodynamic shapes.
Lloyd
Re: Help Us Explain Crater Formation!
Impacts Produce Plasma & Electricity * This seems to be an important paper; it shows that crater formation involves plasma & electrical effects, even with bolide impacts: http://www.osti.gov/bridge/purl.cover.jsp;jsessionid=CEF93A~. The more massive or fast-moving the impactor is, the more plasma and electrical effects are produced by impact.
The net charge liberated from an impact is zero, but, over the range of experimental conditions, the magnitude of the positive or negative charge carriers (Q) was found to have an approximate linear dependence on mass (m) and to have a strong dependence on impact velocity (v): Q = 9e-9 m^(0.9+-0.15) v^(2.75+-0.4) C (SI units) (1)
The negative potential of the early time data in Figure (2b) and the positive charge of the ejecta landing on the plates at late time are consistent with early ejecta acquiring a negative charge and leaving behind a residual positive charge in the plasma, the transient cavity and material ejected at late time.
In addition to plasma, a typical hypervelocity impact will produce melt and fragmental debris. Because electrons are much more mobile than ions, any debris in contact with plasma will typically acquire a negative charge. Inertial separation of the materials could then lead to separation of charge over macroscopic distances. This process, similar to static electrification that occurs in thunderclouds, can lead to substantial electric fields that are surprisingly easy to measure in the laboratory.
* The next image shows that negative charge tends to be blasted away with the ejecta of an impactor, while the plasma left behind attains positive charge. The object labeled PLASMA is the impactor, whose surface is plasma of undetermined depth.
Fig. 5. Possible configuration of charge that explains the data.
Table 2. Electromagnetic properties of representative impacts. t (sec.) E (Volts/m) I (Amps) B (Tesla) [e means "10 to the power of"] 1) Laboratory 2e-3; 8e5; 4e-3; e-9 2) Leonid Meteoroid 3e-4; e5; 0.02; e-8 3) Small Meteoroid 4e-3; 2e9; 180; e-5 4) 1 km Asteroid 100; 4e12; 2e10; 0.03
In the presence of 10 V/m electric fields, sub-micron dust grains, with just a few excess electrons of charge, will acquire accelerations of several km/s2. Perhaps electrostatically-driven dust transport may occur during impacts on airless bodies.
It has been known since Apollo that the Moon possesses a patchy remnant magnetism associated predominantly with heavily cratered terrain [8].
We suggest that macroscopic charge separation and subsequent magnetic field production during hypervelocity impact may play an important role in understanding the lunar magnetic record.
We estimate that a 1-5 kg meteoroid impacting the lunar surface at 15 km/s would, in the process of making a 3-m crater, produce a several thousand nanotesla field for 4-8 milliseconds (Example 3 in Table 2), long enough for small beads of impact melt to acquire a permanent magnetic remanence.
Lloyd
Re: Help Us Explain Crater Formation!
Crater Experiment Repost * I'm reposting this image, because I now have a little more explanation to go with it from the owner. It looks like I was mistaken, when I said earlier that I thought the impact was from a bullet fired into material. It seems now it was a ball of cement that fell into powdered cement.
The owner said: I have some video which was transferred from a 16 mm film home movie showing an experiment demonstrating impact crater formation. My father made it along with his mentor (Dr William Rhodes) while he was working on a degree back in the mid '50's. A base of dry cement powder, such as Portland Cement straight out of the bag, un-compacted, was used as the target. I don't know the thickness [probably 2 to] 6 inches deep. A ball bearing was heated and used to melt two spherical halves in two wax rods which were then used to scoop some dry cement powder into an un-compacted ball. The wax mold was two separate hemispheres, which were gently pushed together while scooping the powder into them. Placing the mold on the platform and gently pulling apart the two halves left the spheroid of powder that we see. You can see a Still where the ball of uncompacted cement powder is sitting on a platform, then falling by gravity when the platform is suddenly removed using parts of a mouse trap in the design and some kind of electrical trigger to snap the platform out of the way. The idea being that the two bodies have the same composition and density and gravity as the accelerating force. I would estimate the length of fall to be around 4 to 6 feet. The impact was filmed at 5000 frames per second and is very mesmerizing to watch with ejecta continuing to fall in slow motion for maybe a minute. You can even see the ejecta body falling which created the secondary crater, which looks much more circular in shape to me than the main crater does. I made a transfer of all of my dad's 16 mm movies onto one VHS tape using his original 1950 movie projector and a home VHS camera back in the '80's. The projector has a variable speed knob which I used to lessen the flicker. I will attempt to copy the VHS to CD, then send it on.
biknewb
Re: Help Us Explain Crater Formation!
Years ago I read about experiments like this one. An "impactor" of powdery substance - like cement or flour - was dropped in a layer of the same or another powdery substance, resulting in a crater, complete with a rim and ejecta. The flat floor gives the impression of a faithful reproduction of a lunar crater, but is probably caused by the solid base under the layer of powder.
The experiment likely was inspired by the idea of asteroids being loose conglomerates of rubble and dust.
It did not convince me then (which must be obvious from the above )
* William has now uploaded his Dad's video of the crater experiment to http://www.youtube.com/watch?v=askWCfw1-mw. The more interesting parts of the video are toward the end, because most of the rest is a bit dark.
Shelgeyr
Re: Help Us Explain Crater Formation!
I surfed across this picture of a small crater in Russia today:
Craters are circular anticlines. see http://en.wikipedia.org/wiki/Anticline . The magma is (or was) pushing under the crust creating a multi-floor pattern and thinning down of the crust. On earth the phenomenon is well known for mid-ocean rifts and continental rifts. The difference between anticlines and rifts is that the magma reached the surface for rifts, but not for anticlines.
On earth the sea floor is made by this rift system. And it is the case on other planets too. On moon the basalt sea floor is called mare and most craters are circular anticlines explaining the plentifull of concentric craters. The most spectacular of the moon is the mare Orientale, this mare is inside the "moon's far side" high land. Like the opening of the red sea and the east african rift, the mare oriental has a multi floor pattern : http://apod.nasa.gov/apod/image/0211/ma ... er4_c1.jpg google map : http://www.google.com/moon/#lat=-19.062 ... =5&apollo=
http://www.accuracyingenesis.com/mapchain.jpg The vulcano archipelago leading to haiwaii is clearly seen in google map: http://maps.google.com/maps?f=q&source= ... 72&t=h&z=4 They are built by a geological "hot spot" pushing magna in that part of the globe. But due to the slow plate movements and continental drift, these hot spots can errupt in other part of the crust over time. New eruption zones are aligned with the older ones (or at least aligned with the crust movement vector in tectonic)
The Definitive proof is that in Richat structure , the different craters are not of the same age. As shown here : http://earthobservatory.nasa.gov/IOTD/view.php?id=8536 . Just like hawaii is the youngest of the aligned vulcanos (and midway is older, for example)
The analogy with Electric Discharge Machining made by David Talbott and Wallace Thornhill here : http://thunderbolts.info/tpod/2006/arch ... crater.htm is just an analogy. In geology, this pattern is explained by under-earth magma pushing the upper crust. The Electric Discharge Machining is probably triggering the same upper crust pushing in industrial metals. There is no certainty this magma pushing is powered electricaly for geological rifts. Nevertheless, geological theories are in need of energy: Plate tectonics (mainstram) needs energy to power the convection in the mantle responsible of crust's plate movements. Current model bet on radioactive decay (and this is doubtful) Expanding earth model needs a way to empower the matter creation process. The exponential sea spreading is curently in favor for expansion http://geology.geoscienceworld.org/cgi/ ... ct/5/5/313 . we talk about it here : viewtopic.php?f=10&t=1184&start=735#p51940
davesmith_au
Re: Help Us Explain Crater Formation!
platyhelminth wrote: The analogy with Electric Discharge Machining made by David Talbott and Wallace Thornhill here ... is just an analogy. In geology, this pattern is explained by under-earth magma pushing the upper crust. The Electric Discharge Machining is probably triggering the same upper crust pushing in industrial metals. There is no certainty this magma pushing is powered electricaly for geological rifts.
And your idea is an interesting idea ... just an interesting idea. However it fails miserably to explain the surfaces of small bodies which are heavily cratered.
Comet Wild 2:
Comet Wild 2 original image credit Stardust/JPL/NASA
Phobos:
Phobos original image credit ESA/DLR/FU Berlin (G. Neukum)
On such small bodies lacking in magma, how do you account for these and the many many like them?
Cheers, Dave.
platyhelminth
Re: Help Us Explain Crater Formation!
davesmith_au wrote: On such small bodies lacking in magma, how do you account for these and the many many like them?
Yes it has to have some kind of movement, no matter how fluid is your asteroid. We know clearly that rocks can act as fluids . anticlines are an example of rock fluidity, the upper layers (not magma!) are distorted by the pressure from inside : http://www.fas.org/irp/imint/docs/rst/S ... ig2_29.jpg
May be your electricity heats up the rock inside enough to make pressure on the asteroid crust. Just like earth's craters. Thats the best explaination. You solve the power behind tectonics on earth if you can prove electricity can do this on asteroids. For the non-mainstream expanding earth model, matter creation must happen somehow in the asteroid.
Craters (particularly those with concentric circles) are not due to exterior pressure, but to internal pressure as I explained before. Even if electricity come from out-side, it must act in the interior.
CRATER ANOMALIES * The Mar 06, 2006 TPOD, "Man in the Moon" at http://thunderbolts.info/tpod/2006/arch ... 05moon.htm, has this list of crater anomalies, which are said not to be explained by impact theory, but are by E.D. Theory. 1- Lack of debris ........... Adjacent craters lack debris expected from near-ground explosions. 2- No overlap ................ Larger craters do not overlap smaller craters. 3- Minimal disturbance .. There's minimal disturbance where one crater cuts into another 4- Undisturbed basement .. Shattered basement rock is not found 5- Rim craters ............... Many secondary craters occur on rims of larger craters. 6- Rim crater chains .... Chains of small craters occur on rims of larger craters. 7- Tangential rays ......... Rays of "ejecta" are often tangential to crater rims, as if ejected from rims. 8- Concentric rings ....... Many craters have concentric rings. 9- Terraced walls .......... There is unexpected terracing of large crater walls, with melted floors of some terraces. 10- Flat floors ................. Crater floors are flat-bottomed and melted instead of dish-shaped as from impact blast. 11- 11- Crater lines .............. Many craters are in pairs or straight line chains. 12- Steep walls ............... Crater walls are steep, instead of shallow dish-shaped. 13- Circular shape .......... Craters of all sizes are remarkably circular. Oblique impacts should form oval craters. 14- Associated rilles ....... Craters often adjoin cleanly cut gouges and rilles. 15- Cratered asteroids & comets.
* Anticlines are unlikely to explain most round and hexagonal craters, especially on moons, Mars, Mercury etc, as anticlines should have irregular shapes.
platyhelminth
Re: Help Us Explain Crater Formation!
1- Lack of debris & 2- No overlap & 4- Undisturbed basement Anticlines and rifts are not impacts. there is no debris, no Shattered basement rock 3- Minimal disturbance Anticlines are relatively slow, thus making minimal disturbance. 5- Rim craters the magma (or rocks under the crater) is continuing to make pressure on a close crust spot. Thus leading to the opening of other craters. Ultimatly, for planets, if the pressure of magma is continued for a long time it may lead to basalt sea floor like on moon's mare, earth's south hemisphere+pacific and mars's north hemisphere. 6- Rim crater chains & 11- Crater lines For the same reason vulcanos follow a chain on earth (except that for Anticlines magma has not reached the surface). The chain follow a sismic line. In the cases of moon's mare (and earth seas) we can see rilles or rifts. http://vulcan.wr.usgs.gov/Imgs/Gif/Indo ... canoes.gif 7- Tangential rays Yes, just like the photograph I posted in my previous post with the fractured vulcanos in the east african rift: http://www.swisseduc.ch/stromboli/perm/ ... .html?id=6 8- Concentric rings the magma (or rocks under the crater) is continuing to make pressure on the exact same crust spot for a long geological time with the same intensity during time. Thus leadind to regular concentric lines like the mare orientale (but mare orientale is a bad example since the lava reached the surface, thus it can no longer be called a circular Anticlines, it is a rift system) in a Anticlines, the center is either a dome (if the layer of rock in center has not cracked) either a small crater (if the layer of rock in center had cracked) either flat. 9- Terraced walls & 10- Flat floors Yes, that is basalt sea spreading for the rift system. Anticlines http://upload.wikimedia.org/wikipedia/c ... PSF%29.png , important to add it earth has many linear (non-circular) Anticlines. 12- Steep walls Rift system and Anticlines lead to cliffs formation as I said in previous posts. 13- Circular shape Anticlines are not impact. They are cicular for the same reason vulcanos are circular, the only different is that Anticlines have not emited magma (and may never erupt, they are just structures due to the internal pressure) 14- Associated rilles Yes, they are linked to the rift system. Anticlines are basicaly the same. 15- Cratered asteroids & comets I already emited an hypothesis previously.
Lloyd wrote: * Anticlines are unlikely to explain most round and hexagonal craters, especially on moons, Mars, Mercury etc, as anticlines should have irregular shapes.
Lloyd wrote: such as Aorounga? There are lots of anomalies with most such craters. I doubt that the parallel markings on Aorounga are faults.
The terrain map reveal a sort of "large rift" (with parallel cliffs) : http://maps.google.com/?ie=UTF8&ll=18.5 ... 61&t=p&z=8 In The geological map http://www.fdi.net/documents/WorldBank/ ... s/Geol.pdf we see clearly that the "large rift" (parallel cliffs) are in fact parallel layers of different dates (relatively old, the different layers are organized by chronological order. This can be a Anticline pattern as I explain here http://img709.imageshack.us/i/geolchad.jpg ). The north east of Aorounga is a very recent cenezoic volcanic activity. Aorounga is clearly at the margin between the recent Cenezoic vulcanos and the old devonian cliffs. The parallel small crack lines present in Aorounga are caused by the very recent vulcanic activity. This place is cracking because of the pushing of recent vulcanism.
http://thunderbolts.info/tpod/00subjectx.htm#Craters wrote: Because a mineral sample's age depends on that sample existing today exactly as when it was initially formed, if it has been affected by radioactivity, or heat, or a blast or electricity, any measurement of its age will be inaccurate. Therefore, if a multi-billion joule electric discharge, sufficient to excavate a crater 19 miles in diameter were to strike the earth, the gamma and x-ray pulses would drastically alter the decay rate, the isotopic ratios and, perhaps, form new elements within the rocks.
Then why the geological map show a pattern so easily interpretable ? with layers carefully present in chronological order ? Radioactive decay is also very reliable (considering the radio-element input of the past was the same or similar). Only a nuclear chain reaction of these radioelement could affect it (usualy impossible with nature's concentration).
That is sad no geologist is associated with EU theorists. Some theories have realy multi-disciplinay implications. I am just an amateur geologist with a scientific background in another field.
Lloyd
Re: Help Us Explain Crater Formation!
Platy said: That is sad no geologist is associated with EU theorists.
* There are several geologists associated with EU. EU is a result of interdisciplinary collaboration. If your conclusions were correct, I'm sure our geologists would have noticed the same thing long ago. * Numerous TPODs point out evidence that conventional dating methods, including all radioactive decay methods, are extremely inaccurate. C14 is the most accurate, but can be centuries off too.
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