russell@irondogmedia.com

What are the largest and earliest craters in North America? These are the fifteen that appear to be most important and obvious. The purpose here is not to defend their existence, a gravity map is provided for each one so the reader can recognize their individual energy signature. They are the “new kids” on the block, I want to introduce them and share a little bit about why I want to know them, and let you start to know your neighbors. Before we can make friends of them, we need to start to trust them.

Figure 1: For the author, the search for the big and early craters started with the Gulf of Mexico crater. The more I studied it, the more basin like it looked. If a huge bowl shaped pit had been excavated by a crater, the Gulf is the classical cratering pit. Its sedimentary layering even gives an understanding of fallback and washback ejecta. But, it is deep with information and much more research is needed.

Figure 2: When I started to study the Gulf of Mexico, I only considered the bowl to be the Gulf of Mexico crater, but the sediments extend as far north as the 7-8th ring, southern Missouri, and the original crater rim (OCR) may be as far north as Arkansas, about ring 9. The small Chicxulub crater on the Yucatan shelf is nothing compared to the much larger Serranilla crater that formed Yucatan Peninsula, Cuba, the Cayman Trough, and much of the Caribbean Sea.

Figure 3: The next crater I recognized was the Bermuda. I was curious how Florida came to be protruding into the Gulf of Mexico crater. The Bahama Islands are laying in a 30 km wide portion of very deep water, “Tongue of the Ocean” that I identify as a Release Valley just inside the Original Crater Rim-ring that contributes to Cuba, Florida, and the Appalachians.

Figure 4: The outer rings of the Bermuda crater also contribute to the Mid Continental Rift, red section under the 4-ring, the Front Range of the Rocky Mountains in Colorado, and extending its up-thrust to the High Plateau of Mexico between the Sierra Madre Oriental and the Sierra Madre Occidental.

Figure 5: The Keys crater lie under both the Gulf of Mexico and Bermuda craters. Fractures from it defined the Sabine Block of the western gulf and the eastern Texas area. The elevated heat the Keyes crater put into the substrate combined with the Gulf of Mexico crater’s heat to allow the Bermuda crater to push Florida up in a gneissic dome instead of a rocky mountain.

Figure 6: Being a relatively early crater, much of the energy signature of the Keyes crater is swamped by later cratering. Yet, we can see how the western edge of the Gulf and the southern arc of the Sierra Madre Oriental conform to it. Later craters do not obliterate, just add their energy envelopes to the ripple pattern. Can you see the blue ring inside the sixth-ring and under the fifth-ring?

Figure 9: The Alvord crater made the second contribution to the Sevier Orogeny, but its second and third ring extend too far into Wyoming to be the major contributor. The Great Basin at the center is all that remains of the cratering basin. Looking between the fourth and fifth rings, the white squiggly line is the path of the Colorado River through the Grand Canyon, and those rings extend up into Wyoming as the Intermontane and Bighorn Basin. These are areas of the Rocky Mountains with raised topography and extremely shallow Moho in the crust. The adiabatic response of the blue ring is why.

Figure 8: The Gorda’s ring structure was first recognized off of the coast in the slight bend and wide trough that later formed in the center few rings. The Gorda’s heat contribution allowed the far annulus from the later crater to have a greater expression with in those rings.

Figure 10: The wide area of dark blue between the third and fourth ring is obvious in this gravity map. This is what I refer to as a Release Valley, the adiabatic response zone following the shock wave. It forms as the wave moves from the high energy compression wave to the low energy of the expansion release-wave portion of the energy signature.

Figure 11: The third crater adding to the Sevier Orogeny is the Blowout Mountain crater. It is the crater which left the surface traces of the Sevier Thrust Belt at the western edge of Wyoming and down across Utah. It is also the major thrust behind the Kaibab Uplift of the Grand Canyon.

Figure 12: This stacking of the three thrust from three different cratering events within roughly the same area is the source behind the idea that the Sevier orogeny is a “thick skin” mountain building process going deep into the Precambrian rocks, reactivating original Precambrian faults. The narrow dark blue band just inside the sixth-ring, which cuts off the south end of the Sierra Nevada, sets the Blowout Mountain crater apart from the Alvord crater. They were not the same thrust.

Figure 13: Tatanka is the Lakota word for the buffalo that roamed the area. The major sedimentary and hydrocarbon Williston basin is indicated. The peculiar high spot in the western edge of the basin, the Bearpaw and Little Rocky Mountains, represents the central-peak or peak-ring of a complex crater on the moon.

Figure 14: The rings of the Tatanka crater are recognized by the blue ring just inside the third-ring and sixth-ring. The fourth-ring seems to be the next energy events in the red area of the Mid Continental Ridge after the Bermuda crater.

Figure 15: The Maka Luta, Sioux words for “red earth,” crater is possibly the most important crater for the US. It defines the “foundation” of this portion of the continent. It’s the up-thrust defining the continental shelf on the Pacific, Atlantic, and Gulf coasts. The first-ring again defines the Front Range and the western limits of the Denver-Julesburg Basin, which is the eroded remnant of the impact basin.

Figure 16: With added information, outside the first ring’s Denver- Julesburg basin, the Maka Luta crater defines several important hydrocarbon basins including the Powder River, Bighorn, Mowry, Niobrara, Greater Green River, Uinta, Mancos, Hermosa, Paradox, and San Juan Basins. This suggest hydrocarbons have their primary source from the deep mantle rather that fossil organics. Looking at a map of the Sauk Megasequence finds it is defined by the Maka Luta’s eighth-ring. This includes the Tapeats Sandstone of the Grand Canyon region.

Figure 17: The Foxe crater is one of the largest mappable craters in North America. The tenth-ring largely defines the Canadian Craton and also the northern reaches of the Sauk Megasequence.

Figure 18: The center of the Foxe crater appears primarily blue, and becomes deep blue inside the sixth-ring. If the reader would care to compare it with the gravity/GRAIL view of the lunar South Pole-Aitken crater’s center, there are several remarkable visual similarities. Tomographic sections through this area shows the low gravity blue extends downwards between 300-500 km, which is well through the lithosphere and asthenosphere. These large early crater show that it is not the mountains that have very deep roots, but the craters.

Figure 19: Very early craters are challenging to identify, but the Pedregosa crater suggest it is a very early one. This is based on its identification as the center for concentric expression in the Pelusiam Megashear of North Africa. That a point could be recognized as having a small circle relationship to a linear half a globe away suggest a great coincidence or a point application of a huge shear force, such as a very large impactor.

Figure 20: The best recognition clues for the Pedregosa crater is the blue areas just inside several of the white ring linears. The one just inside the third-ring is most pronounced, including a significant portion of the northern reaches of the Gulf of California.

Figure 21: The MCR crater is named for the Mid Continental Rift that it contains. The Tatanka and Bermuda craters have been mentioned as contributing their energy signature to the Mid Continental Rift. While I drew rings for both of those craters that align with the Mid Continental Rift, the dark blue area along both sides of it suggest it was the release valleys/expansion waves that aligned. One other “chance occurrence” is the alignment from the Ipojuca crater, which is certainly a release valley expression. The Mid Continental Rift is believed to represent a failed rift across the central partion of the continent. I propose it is a buried trench like those on the sea floor that represent release valley expressions, not rifting.

Figure 22: The visible high gravity expression of the Mid Continental Rift is exactly as long as the diameter of the second-ring of the MCR crater. I would refer to this as the Open-ring that would correlate with the rebounded crust under a lunar crater. Then the Mid Continental Rift would correspond to the Mascon (Mass concentration) found in many of the larger moon craters. It has been broken up, twisted, and shaped by several later smaller craters. Towards the eastern sea coast, the MCR crater had a remarkable effect on the final shape of the Appalachian Mountains.

Figure 23: The “Aguj de Anahuac” crater was chosen to mean “Pit of the ancient Mexican people”. It arrived after the Gulf of Mexico crater, and shaped much of Mexico, pushing it back towards the gulf.

Figure 24: Aguj de Anahuac crater emphasizes the major blue/low gravity valley that underlays most of western Mexico. This crater has little to do with that trough of low gravity but crosses it. It shows up as a thrust fault regularly in the midcontinent region, but has some of its most conspicuous energy signature showing on the Eastern Pacific Ocean floor just south of the center, not visible here.

Figure 25: Having its center in the Irminger Sea, between Greenland and Iceland, the Irminger crater is the most distant crater from the North American continent. Its timing may have coincided with the Tatanka or the Maka Luta. It comes up repeatedly in trying to map thrusting linears in the central continent, and is a major contributor to the southeast-northwest portion of the New Madrid, Missouri earthquake zone.

Figure 26: The third-ring of the Irminger craters has some gravity ridges that look strikingly similar to the Mid Continent Rift. It would be an interesting study to see if they also had some structural similarity. The eighth-ring is concentric to the Canadian Rocky Mountains. The Tasman Sea crater seems to be the source of much of the up thrust in the Canadian Rockies from the southwest, but it may be that the Irminger crater adds to that up thrust from the opposite direction as it does several times across Colorado, Utah, Wyoming and Montana when viewed is much greater detail. Two to three linears around the Grand Canyon appear to conform to segments of the Colorado’s path. This suggest it may be a significant contributor forming Grand Canyon faults.

Figure 27: The Great Beaufort is another crater that seems rather far from North America. It arrived very near the time of the Maka Luta and Foxe craters because it is a third crater that made a significant contribution to sandstone deposits in the north of Canada and Alaska in the Sauk Megasequence. The Great Beaufort crater also seems to be the energy source behind the Franklin Large Igneous Province that opened up some of the Foxe crater’s faults as extrusive conduits for the lava. This suggest the Great Beaufort impact may have occurred only hours to a day after the Foxe cratering event.

Figure 28: The Great Beaufort crater was after the Gordo crater. The fifth-ring coincides with the wide trough just off the California coast that I proposed was highly visible because it had occurred within rock that the Gordo crater had already heated. That fifth-ring forms a speckled pattern all the way across the continent, and the sixth-ring defines a section of the Atlantic Ocean’s Continental shelf.

Figure 29: The Caribou crater is the smallest crater considered here, but it forms the island studded Pacific Ocean edge of British Columbia, both Vancouver Island and Haida Gwaii. But, although Caribou crater contributed to the edge of the continent, it did not contribute to the perimeter of the Sauk Megasequence. This may mean that it followed the Fox and Maka Luta craters by a day or more.

Figure 30: The most obvious indication of the positioning of the Caribou crater is the third, fourth, and fifth-rings interaction with the Cordilleran. The compressive high gravity ridges under the white rings are all paired with blue rings on their inside edge. The sixth-ring is bordered with blue on much of its distance across the midcontinent, and even when the color is all blue, as in Canada, there is a lighter blue just under the white ring signally a slightly higher gravity in that area.

Figure 31: Although I have introduced each of these craters one at the time, we must never forget they are a gang, and when we look at any single geomorphic characteristic of our Earth, we may be looking at the result of 6 or 8 individual energy thrust but acting as a gang. Sometimes the assigning of responsibility is relatively straight forward, but sometimes it is a Gordian knot defying separation into its parts.

Figure 32: Looking at them as a gang, does not a gravity map resemble a quiet pond’s surface which has had a couple of handfuls of pebbles tossed into its depth? Trying to figure all of the pattern out mathematically may stump even the largest supercomputer. Yet, taken one-at-a-time, and with a minimum understanding of how the ripples interact constructively and destructively, we may be able to follow a ring enough that our confidence is established and a center allows us to expand and integrate much of the energy signatures into a pattern of work accomplished. A confusion of circles can be decomposed to understand the implications of the pattern.

To understand the geological history of our planet, we need to see and understand all of the evidence available to us. Part of that evidence is the recognition of lineaments in the landscape visible in satellite pictures available as Landsat images used by Google Earth. Gravity maps, such as Global Gravity Anomaly, downloaded from Scripp’s Institute of Oceanography as “Marine Gravity Anomaly,” an overlay for Google Earth, provide valuable additional information.

Figure 1: The Vredefort Impact Crater of South Africa is considered to be one of the largest and oldest recognized impact craters on the Earth’s surface. It makes a pattern of concentric circles that are hard to miss on a satellite image. These implied lines in the landscape are referred to as linears, and the partial circles they form in this image are called “circular” or “arcuate lineaments.”

Figure 2: Some of the other craters that show up in this Landsat view had a major effect on the visibility of the Vredefort crater. Blue circles are three rings of the Vredefort Dome crater. “D” is the dome and “C” is the collar structures. The first blue ring is drawn just outside the collar. Blue 3-ring shows the strongest with mountain arcs showing to both the west and the east. Yellow circles 1-4 are the primary reasons the collar terminates to the southeast. Yellow 5-ring is most likely an earlier, larger crater which maybe more responsible for defining the Witwatersrand than the Vredefort Dome since it came earlier and was apparently larger.

Figure 3: Many of the linears show differences of topographic features. When the topography is viewed from an airplane, even when the elevation has been exaggerated as in this image, the circular pattern is not near as evident, because much more than just large topography produces visual linears. Any true pattern in these small features may only be observed when we are directly overhead. Other patterns can only be perceived when our field of view is much larger.

Figure 4: But, with the Vredefort Structure, careful geologic study on the ground has verified a lithologic pattern that is very consistent with a circular impact origin. While the Karoo Supergroup covers the southern half to the crater it was not responsible for the lower elevation of the ring. Instead, the yellow 1-ring of Figure 2 swallowed the heat signature’s energy imprint never allowing the ridge to thrust-up.

Figure 5: This is a very different map of the Vredefort area. Known as Global Gravity Anomaly Map overlay for Google Earth it is based on slightly different strengths of gravity as measured by satellite altimetry. Generally referred to as Free-Air Gravity Anomaly, the red areas measure a little higher gravity and the blue areas measure a little lower gravity. The differences in the pull of gravity is thought to reflect differences in topography and thickness of crust, but as the visible pattern differs markedly from a simple topography map, there must be something else involved.

Figure 6: The three pairs of circles I have drawn here relate to three different guesses as to the original crater size for the Vredefort Crater. The inside red circle is the diameter (160km) recognized by the Earth Impact Database. The blue circle is the diameter (>300km) given by Wikipedia, while the white (500 km) given by this author as the most visible in the Gravity Anomaly readings. Yet, all three circles point out two good principles.

Figure 7: 1) The colored circles were located in Landsat images, where dark shadows of ravines are more pronounced than ridges at this resolution. These more pronounced circular lineaments correspond to low gravity readings. 2) The inner, thin white circular lineaments, correspond more with higher gravity readings on this map. Yellow arrows indicate points of pronounced gravity change consistent with a circular impact lineament.

Figure 8: If we apply these same principles to all of southern Africa we will note some interesting results. The southern half of Africa has a shape we all recognize in a standard satellite image. But, look at it in Global Gravity Anomaly…..

Figure 9: Can you pick out the continent shape in this Gravity map??? If this is a new tool for you, take a few minutes; flip back and forth between the pictures until you can see the outline of southern Africa. Can you pick out a near circle of red to yellow in the southern Africa region? Let’s focus on that circular area.

Figure 10: I call it the Mabule Circle, named for a small town near its center. It is seen here in Free Air Gravity Anomaly map published by BGI, France. You may also notice the name Vredefort just below the word Mabule. The Vredefort Crater is located within the Mabule Circle. Based on the Vredefort Crater being an accepted crater, but its gravity pattern showing less distinct changes in the gravity readings, the red circle here shows a very strong circular lineament that could be a much larger circular crater.

Figure 11: While the red expression of the circle has been interrupted at the top and bottom, it has not been totally obscured at either place. This is partial occlusion at these points. It shows something has interfered or covered the expression in that area and not that this isn’t a complete circular expression. We will discuss partial occlusion more shortly.

Figure 12: Here is the Mabule circle with a much heavier line that might help you see it. When I am locating circles, I prefer a lighter line, as my eye is drawn to the heavier line, and I do not feel as able to objectively evaluate its presence. The Mabule circular lineament is one of the strongest on this planet. So, if we are going to start seeing these lineaments so we can understand them, this is a good place to start.

Figure 13: What can we really see? Looking at the same circle on a Terrane Map, the circle does correspond to many mountain ridges, gullies, rivers, and other topographic features. Take your time. Examine the circle carefully. You will only start to see these circles as you take the time to train your eyes.

Figure 14: Bouguer Gravity Anomaly is the Free Air Gravity Anomaly adjusted for the surface rock above sea level. It is as close to a gravity reading for only the crust that we can get. The Mabule and Vredefort crater and their centers are indicated with a light white circle for the crater rim and a place marker for the center. Neither show-up quite as well as in Free-Air Gravity Anomaly.

Figure 15: Yet, several incomplete circles show up in the Bouguer Gravity Anomaly. There are three marked with several black dots each. One overlapping the Vredefort circle to the northeast, a second overlapping to the southeast, and a third completely separate to the west.

Figure 16: Could you find all three of these yellow rings? Take time to flip back and forth between these images to see if you can recognize the indicators I used to identify these circles. All 4 of these smaller craters would have much greater differences in deep crustal lithology which the Bouguer map reflects rather then mountain peaks that the Terrane map reflects for the Mabule crater. There are also several other circles that can be seen here. Are all of these circular lineaments?? The next image will show some additional circles. As each of these different maps show different things, this is a strong reminder that we need to look for circular lineaments in any map we can see them in, as they find expression in different forms under differing conditions.

Figure 17: Check out the orange circles. Flip back and forth, again. Does knowing where to look help you see them?? This still is not all of the circles that can be recognized. In someways, eliminating some of the peaks leave the remaining curves more evident.

Figure 18: Other rocky bodies in our Solar System seem to be covered in craters, why don’t we see them on the Earth?? One of the excuses given is the large part of our planet is covered by water. But, with Google Earth’s inclusion od NOAA data, this is no longer a problem. This is the Eastern Pacific; if you look closely, maybe you can just make out some linear patterns running east and west through the dark blue ocean. While these aren’t circular craters, maybe they are still related to impacts.

Figure 19: Here are some of the more visible lines/ linears. Linear patterns are something we can see all over our globe. Some are circular, but many appear to be straight or nearly straight lineaments.

Figure 20: Here is the same area after converted to black and white and having the contrast raised. We can see those same linears so much clearer. We must also learn to ignore the myriad of diagonal linears going every which way. These “tank tracks” are a factor of extra data gathered in standard shipping lanes. The most obvious lines are thousands of kilometers long. Of course the question arises, “Where did they come from?? What is their meaning?” Plate Tectonics has explanations for a few of these lines, suggesting they are where the plate’s movement slowed down and stalled. But, they are too regular for such a random explanation. S.P. Gay, in an address to the American Association of Petroleum Geologist in 2012 said, “To not attempt to understand lineaments is to ignore one of the most common and basic features in geology.” My goal here is to help you start to see circular and straight lineaments, and hopefully as we see more of them; the patterns will emerge and we can start to understand where they come from. Where are their points of shear?

Figure 21: This is the Global Gravity Anomaly Map of the exact same portion of our globe. In gravity maps, blue represents lower gravity readings and red higher readings. Notice while the myriad of diagonal lines all vanish, yet, the east west lines become very defined as dark blue lines. We will notice one more thing, details do not generally show up very well on Gravity maps. Gravity maps used here are lower resolution then Google Earth Landsat images. Actually, the detail possible in Landsat images is pretty remarkable. We will look at this again later. Be aware, I don’t believe any source for these linears can be found that explains them as well as impacts. But, the basic problem for many people is seeing them in the first place.

Figure 23: In seeing lines, we are dealing with a science called “Spatial Perception.” Is there a pattern in the words in this image?? Is it random or planned?? Does there seem to be a purpose to it?? Can you identify that possible purpose?? Just because you do not know a purpose, it does not mean we should ignore that a pattern is there. Because you can not yet answer the final question does not mean that we can ignore the previous questions. Any non random pattern reflects some cause or purpose. Energy was expended to make any pattern. Complex patterns do not happen randomly.

Figure 23: Look at this small white area. There are two short lines or linears like we might see on a map in the form of a stream or a rock outcrop. Look closely, can you see a pattern in them?? Are you maybe not sure??

Figure 24: If we add this additional linear, does it help?

Figure 25: How about a little more information. Maybe now we are starting to see a pattern. Maybe the top three are a line. But, then what about the two towards the left bottom. Sometimes we cannot see a pattern because our field of view is not large enough.

Figure 26: Sometimes just a little more information will give a much clearer idea of the pattern, if there is one. We are starting to see three lines. Maybe this is a triangle. But, then we must ask the question, is this the entire pattern?

Figure 27: But, sometimes it takes a whole lot of additional information before we can apply Spatial Perception with confidence. But, just because we can see a pattern, the importance is not in what we can see. The importance is in the purpose of the pattern.

Figure 28: Spatial Perception allows us to mentally fill in and complete patterns. There may be multiple solutions, and we may have to follow each one through to its logical end to test whether it is likely or not. Using Spatial Perception we interpret the lineaments into the pattern we think most likely, and share that interpretation with others.

Figure 29: This is my interpretation of this pattern, colored to make it more visible. Seeing a nonrandom pattern gives us assurance that a purpose does exist. We may not understand the purpose. We may have all kinds of questions about this figure. Is there a white triangle in the pattern?? Is there a black triangle?? Are there three black circles or are they “Packman” figures?? If we do not admit to the white triangle, then the black triangle and black circles can not exist, and we are looking at 6 repetitive, but strange geometric shapes. They would still not be random. There is repetition of elements in a consistent arrangement. There is a type of radial symmetry at three places which gives us repeated elements. And, there are parallel elements that show a common purpose exclusive to this arrangement. All of these are interpretations about the pattern, but first we needed to determine that it existed in the sketchy linears we started with.

Much of this website will cite cratering evidence from North America, because that is where the author physically is located. This look at southern Africa was started because the ring of the Mabule crater is the most obvious circle globally in gravity maps. But, I also wanted to see if cratering as I am coming to understand it from North America holds true over the entire globe. With this look at many of the larger craters found around South Africa, I believe it confirms that my understanding of cratering applies globally.

Figure 1: The Witwatersrand Basin of the Kaapvaal craton under South Africa’s Vredefort Dome Structure holds the largest goldfields in the world. How did the gold get there? Did the Vredefort Structure/crater have anything to do with it? Was it the collision between two tectonic plates? Was it eroded out of long forgotten mountains into a near shore reef? How does the cratering history of South Africa relate to its gold??

Figure 2: Gold in the Witwatersrand Basin is found in “reef” deposits, where the native gold occurs as particles that are believed to be detrital in origin. The particles of gold are found among rounded quartz and pyrite pebbles along with an abundance of kerogen and bitumen in the “carbon” reefs. Many yellow-green diamond are found in some “reefs,” and were a valuable commodity in the early nonmechanized mining era. Now, all of these superfluous items are smashed fine to get at the gold.

Figure 3: (A) Google earth image of Vredefort Dome Structure with enhanced color, showing the arced ridges of the Collar giving it the unmistakable visual image of a crater. The collar is a circular thrust, and is in keeping with a crater, but the thrust layers continue outwards for an additional 80-100 km. The collar thrust was a circular expression of the shear energy, but it was not the only one. (B) Isopachs contour lines based on the amount of annealing in the Planar Deformation Features (PDF) are indicated. The contour lines suggest the location of four straight lineaments (CGRS) that cross the energy pattern of the crater that were also produced by points of shear.

Figure 4: PDF samples not from South Africa, but showing two sets of PDFs in each sample. The second set annealed spots in the earlier set. PDF are a type of very fine parallel fractures in the quartz crystals. They are produced by shock-waves passing through the crystal. Multiple craters from different direction produce different sets of PDFs. When later sets occur, the shock-wave’s passing is accompanied by significant heat and the second set of heat waves anneals (melts together) spots in the first set of PDFs. So, the pattern of differing amount of annealing in Figure 2B is an indication of the total amount of heat from the passing of multiple shock-waves at that location.

Figure 5: Looking at a larger area around the Vredefort structure. Moving outwards, the three views show the persistence of linear patterns that cross the crater. These linears have a small circle relationship and are referred to as Concentric Global Ring Structures (CGRS) because in many instances concentric patterns can be traced globally. Some linears will persist in being seen at greater distance, while others appear and disappear. Circular lineaments also appear, marked with dotted lines and pairs of white arrows. The collar is marked “a” in image A and continues inside the double ring in the other two views. Pairs of white arrows show annulus rings for the impact continue outward to the limit of the viewing field.

Figure 6: The annulus rings continue outward with the collar between the first two, smallest, rings. The 5-ring is labeled in both images for comparative purposes. A few of the other circles that can be seen in these topographic images are marked. Panning up and down in Google Earth will show some circles to be more visible at one elevation and other circles at another. Should this variability of viewing decrease our confidence in identifying the cratering rings? I would say, no. It is to be expected as distance makes some linears less prominent while others blend together to form other patterns. Resolution is an important characteristic, but the release wave-valley (dark ring/“crop marks”) inside the yellow rings in Image B provide confirmation that the higher density ridge exist under the yellow circular lineaments although they are much less noticeable.

Figure 7: Witwatersrand Basin’s goldfields contain the Vredefort Dome Structure (crater) at its center, and the recognized circular lineaments of that crater (Figure 5A) extends over most of the basin. But, rather than the circular pattern of the crater, the goldfield and lifted lithology reflect more of the linear patterns that we saw in Figure 4. WHY???

Figure 8: To effectively see craters and their effect on the lithology, we have to learn to operate in gravity maps. This is the gravity map of Africa, with the Google Earth Landsat image of the exact same area so you can compare and orientate yourself. For this discussion we want to limit our area to southern Africa where the Vredefort Structure and the Kaapvaal Craton are located.

Figure 9: When we get up closer in gravity maps they make more sense, but it is sometimes difficult to retain our orientation. For ease of recognition, I have outlines southern Africa and Madagascar in black rather than include the Landsat image for comparison. In a gravity map, high gravity is shown in red and low gravity is shown in dark blue. Sometimes the high gravity correlates with high topography, and sometimes it does not. Consider the high gravity just off the edge of southern Africa. It is red, but there are no mountains sticking out of the water along that section of the coast. The most visible nearly complete circular form in high gravity is this circle near Africa’s tip. I have named it the Mabule crater.

Figure 10: (A) The Mabule crater with two pairs of circles showing the high ridge for the two rings between these pairs of circles. Some of the linear patterns that are seen in the topography close ups of the Vredefort crater can be seen crossing the entire continent. (B) Some of the other circles visible in topography shown in black. The Ghanzi circle/crater corresponds directly to the Congo Craton and the Giyani circle/crater corresponds to the Zimbabwe Craton. Several circles can be seen around the area of the Kaapvaal Craton, but none of them correspond to its structure.

Figure 11: Using the gravity map, the Chobe, Bulaway, and Zimbabwe craters show up. They all have a distinct effect obliterating the strong circular pattern of the northern edges of the Mabule crater’s rings. This is an indication that these northern craters arrived after the Mabule crater.

Figure 12: There are at least two other larger craters that will need to be accounted for in a final sequence of impact to account for the total lithology. The Indlovu crater, centered near the east coast, produced an up-thrust with its outer ring within the center of the Bulaway and Zimbabwe craters. I will propose the Giyani crater arrived after the Indlovu crater interacted with the Bulaway and Zimbabwe craters and after the Mabule crater had set the continental edges to the south.

Figure 13: The inner Indlovu cratering rings seen in the gravity image. The reader is encourage to note the pattern in shades of blue in the ocean floor east of the continent, as indication of higher gravity left from up-thrust of shock-wave/compression shear from the cratering center.

Figure 14: Limpopo Metamorphic Belt complex terrain formed where the Indlovu crater overlapped the earlier Bulaway craters. The Bulaway crater would have heated the rock into a plastic state, so that the up-thrust of the Indlovu’s ring would buckle it up on edge to form the Northern Marginal Zone. The Indlovu crater-rings also overlapped the Mabule crater where the Witwatersrand strata would later occur and both of them contributed to the energy event’s heat and pressure that would draw the carbon, gold and diamonds from deep in the mantle.

Figure 15: The Witwatersrand Basin is centered under the Vredefort crater, as shown by the last ring in Figure 5A. It is cut off on the west by the Open-ring of the Mabule crater, on the east by the Open-ring of the Indlovu crater and on the north by the Bulaway crater. The up-thrusting shear from these three craters were still in the substrate and active when the Vredefort impactor arrived so all could interact together.

Figure 16: The Bushveld complex is actually a triangular area where the Indlovu, the Bulaway, and the Mabule craters overlap. I will propose the Mabule arrived last contributing its energy and sediments to the already occurring Indlovu and Bulaway craters. The later arriving Giyani crater may have pulled the differentially heated, more plastic, rock up in its crater rebound.

Figure 17: The Bushveld Complex primarily consist of two formationsthe lower complex, a layered “reef” of igneous intrusions, and an upper layer of red granite. While the standard explanation for both layers requires feeder sources from within the crystalline basement or even from the mantle below the Moho; in a cratering context, I proposing they were the first vapor condensate sediments from the three overlapping crater’s vapor clouds (igneous condensates).

Figure 18: The Kaapvaal craton underlies the Witwatersrand Basin and the Vredefort crater, and the craton generally conforms to the crater-ring of the Koster crater. As this craton’s borders do not respect the Indlovu, Bulaway, Giyani, or Mabule craters’ thrust-rings, this crater was laid over them.

Figure 19: Additional conformation that the Kaapvaal Craton was produced in a cratering sequence comes from the Koster craters limiting by additional smaller craters. Craters 1-4 are sketched craters that conform to those limiting edges with energy patterns in the gravity image. Study the four rings to see if you can recognize the gravity indication of a high and low pattern consistent with the input of a shock/release-wave.

Figure 20: Attempting to find conformation of the Koster crater, the tomography of southern Africa was viewed. The Bushveld Province (BP) in image A corresponds to the Koster impactor’s landing spot. Tracing it through the tomographic slices, the bowl shaped arc (1) of its compressed layer (red) are recognized.

Figure 21: The blue center of the green at the center of the Koster crater shows its center was pushed deep offsetting or producing a disconformity that has become known as the Moho.

Figure 22: But, there is an even larger, deeper center to the northeast under the Limpopo Metamorphic Belt that I have labelled the Barbirwa crater. The additional heat center is a major cause behind the Limpopo Metamorphic Belt’s occurrence at this point. Reexamining the tomographic slices at this point suggest they do not go deep enough to capture the bottom of the arc at this point.

Figure 23: Looking at the reaches of the Barbirwa crater in Landsat, it is evident that we are dealing with a crater of much larger dimensions even including an up-thrust in 3-ring that is a major contributor to Madagascar’s topography.

Figure 24: Looking at Barbirwa crater in gravity, we can see up-thrust all around the third ring. Not only in Madagascar and the gravity plateau south of it, but also in the parallel ridge of high gravity to the west of the continental edge. This suggest the Mabule did not operate alone forming the edges of the continent, but its energy and thrust were combined with the earlier Barbirwa’s in that area to determine the ultimate gravity pattern.

Figure 25: Looking once again at the tomographic sections, I have attributed bowl 1 to the Koster crater, however the distinct red compression may not be the bottom of the bowl because a faint blue layer occurs below it, and another red faint layer below that. The 3 red/compression bowl may be the bottom of the Bulaway crater. The 4 would represent the location of the Barbirwa crater occurring below this section. The significant arc 2 would be the correct location for the Indlovu crater’s bowl.

Figure 26: The Indlovu crater is large, but much of it extends over the ocean. By contrast, the Mabule crater is primarily contained by the edges of the continents. I will propose the Mabule crater formed the foundation of South Africa, and was the transition between craters laying down the crystalline crust and the smaller craters that produced the sedimentary cover for the land. The primary difference between the land and the ocean’s floor is not some distinction between basalt and granite, but timing in the cratering sequence when materials in the mantle had been turned over sufficiently to produce as condensates the sandstone, limestone and shales rather than the granitics and basalts of the earlier sediments.

Figure 27: The Indlovu crater stands out in gravity. Elsewhere I recognize a mascon is pulled up inside the Open-ring of a crater. The high gravity between the two white arrows is a mason, whose compression ring is shear from the Mabule crater and the blue/red Open-rings of the Indlovu crater represents its uplifted cratering bottom that limits the mascon’s expression by the Open-ring. I propose the Mabule crater arrived the day after the Indlovu. But, as large as the Indlovu crater is, it was not the first in this area.

Figure 28: The Orange crater, at ~6,900 km diameter to the outside ring shown here, and ~8,000 km diameter to the outermost ring in Figure 29, may be the largest crater in our Solar System or a CGRS beyond that crater’s rim. More study is needed.

Figure 29: The Orange crater starts near the mouth of the Orange River, but extends well into both the Atlantic and Indian Oceans. Its most distinctive topographic features are on the island of Madagascar where three sections of shoreline follow concentric to the rings

Figure 30: While the topography above the water might not show evidence for the impact, the energy pattern in the seafloor’s gravity map does testify to the cratering origin. The ridge between the two red rings and the release-valley between the two blue rings is exactly the structure expected from the compression wave followed by the trough of the release wave from a shock/release-wave pair. I refer to this pattern as the Energy Envelope of an impact. This large energy envelope came from an equally large impact. As the ridge winding through from west to east is part of the “southern Mid-Atlantic Ridge transitioning into the Indian Ridge south of Africa.” It still is a gravity ridge having nothing to do with the concept of Plate tectonics. Cratering does not ignore the evidence for ridges and valleys on the ocean’s floor, but it recognizes different reasons for their structure and origin.

Figure 31: This is the west end of Figure 29. It shows that the energy envelope evidence make much more sense when we are able to find the added circles (energy envelopes) of overlapping craters. Crater 1 here defines a section of the Orange crater rim that conforms to the red-rings, and outside crater 1 there is a distinct blue ring cutting this up-thrust red-ring. The blue-ring trough of the Orange crater is also much more distinct within this white-ring. Whether this is an earlier or later crater is indeterminate at this time. If it is an earlier larger crater, it is a distinct possibility that the up-thrust ring of the Orange crater is a mascon within the Open-ring (white-ring) of crater 1. The regular blue lines that cross the Orange crater ridge-ring are reminiscent of the release-wave valleys traced crossing the Sierra Nevada in Chapters 6 and 7.

Figure 32: This is the east end of the Orange crater’s rings shown in Figure 29. Here an even larger crater 1, recognized by its blue-ring inside the white-ring, suggest the Indian Ridge is a mascon, but it is not from the Orange crater. Within this crater 1 a second crater can also be seen crossing the rings of the Orange crater and the Indian Ridge. Ring-2 is largely recognized by the blue-ring inside the white-ring produced by a release-wave valley in the energy signature.

Figure 33: The strongest evidence to recognize the Orange crater continues to be the blue-ring (release-valley) inside the higher gravity ridge/red-ring (compression-rings). While significant parts of the high gravity ridge can be seen, a nearly continues blue release-valley can be traced once the reader has learned to pick them out.

Figure 34: This photo essay has recognition a series of much larger craters than the Vredefort Dome Structure/crater suggest a cratering history that goes back beyond the depths of topographic sections. The origin of the gold is relatively simple. It involves a multi-stage process of larger and large craters pulling up gold and other minerals in a sequence of cratering events which heated the substrate and repeatedly subjected it to surface crystallization under extreme pressure, then lifted the mineral in up-thrusting mascons in the Open-rings of those craters. It was not a continuous cycle of deposition, burial, pushed deep into the earth, and then re-eroded in a continuous maniacal cycle of millions of years, but large craters with huge heat and pressure acting on or near the surface during a limited time of bombardment that produced today’s surface lithology.

Figure 35: These craters not only left a record on the surface of the earth seen in gravity maps, but left a record in their compression layers down into the lithosphere and asthenosphere. We are not looking at a lithosphere and asthenosphere that is mobile, carrying the tectonic plates in continuous wonderings over the planet, but a wholly static lithosphere and asthenosphere topped by the mantle and crust with innumerable discontinuities produced by the deep reaches of the compression layers of many of these craters. Generally and primarily unchanged since the cratering stopped.