Iowa, USA - Impact Crater Map System
Introduction
Iowa and the whole world of geology is stuck in the Humoral Galen era or error stage. The four body humors type of thought. In the case of geology it is not updated with impact theory and is the slowest of any science to update taking 50 years to adopt tectonics. Tectonics was developed by a scientist outside of geology Alfred Wegener. Sadly medicine at least acknowledges the truth of it's long slow development history including the Galen stage. If you read geology they often fail to mention Wegener. Lying to yourself is the worst form of deception.
It is the worst of systems. Below is my system for impact crater investigation. Is this a universal system? No. Every impact is unique. As a forensic impact physics investigator you must follow the evidence not any preconceived imposed structure to bias your findings. That is after all what makes geologist fail. Impact physics is beyond the possible of any laboratory to recreate. It can only be investigated as a forensic event. The second problem with Iowa is ironically it's detail is too good. You really have to back out and look at the surrounding states to bring it back into focus.
1. Established by literature - Iowa is a crater target rich environment. Like Tennessee only the interest of an out of state geology notable got a crater certified. Robert S. Dietz came to Iowa and certified the Manson Iowa Crater along with the use of "shatter cones" to establish impact. Like the Howell, TN Impact Structure the Manson crater was brought to the attention of geologist by local interested parties, in this case the water well drillers who noted the change in water around an area. The believed location of the impact is shown below.
Alfred Wegener
You can read the usual mis-informative article about it at: https://en.wikipedia.org/wiki/Manson_crater
2. Geology Anomaly Map - While you can wait for an out of state expert to come in and certify your states craters, I recommend a more active approach. Now let's lay out the geology anomaly map side by side and visit all the many problems with the lack of any real effort to identify earth surface impact craters and do that correctly.
I think it is pretty easy to see that the Manson, Iowa Crater has been mapped incorrectly.
Iowa, Illinois Crater
James Van Allen the famous professor at Iowa State. Van Allen was entrusted with the checkout of a sensitive field magnetometer on loan from the Department of Terrestrial Magnetism (DTM) of the Carnegie Institution of Washington, DC. In learning to use the magnetometer and its associated theodolite, he made a magnetic field survey of Henry County, Iowa, which was included in the 1932 national grid published by the Department of Terrestrial Magnetism. Reflecting later on this magnetometer, he referred to it as, "...the most beautiful instrument that I have ever used."
I am going to make an observation here, like Tennessee the come and go out of state big shots do not serve the overall impact effort well. Once established incorrectly their findings are set in stone (pun). The issue of dating while always problematic is doubtful given you would first need to account for the progression of many impacts and be sure you are testing the specific impact samples. Incidentally Dietz was also a big advocate of materialistic religion the everything always existed pre big bang thinking. Sadly Dietz also instituted the folly of the shatter cone deterministic without any real understanding of the overarching shatter coning principle which plagues geology to this day. You can read more about shatter coning at: https://www.hillbillyu.com/shatter-cones
But enough of how we got stuck let's get going here.
Impact is the great excavator
3. Strata out of place.- I have a large collection of historic geology books and articles on Tennessee. I find the authors reporting geology anomaly and discussing it with great interest then attempting to fit it into some existing geological theme. The last part is the problem. Sometimes what you need is a new explanation that better fits.
How I place suspect crater circles. Any circular high differential is suspect. That and a central peek is the crater type with central uplift. The problem with this is too much detail. Iowa has been exceptionally mapped.
As you can see the estimate of one million earth surface craters is obviously correct. It is based on the 600,000 Mars craters and the Earth being twice Mars size.
Large impacts may or may not be identified. None are identical. With tectonic folding craters can be squashed into elliptical. Large impact favors old as the impact cascade principle holds for big bang pulverization as well as an individual impact pulverizing the large into small with a chain of impacts. You can read more about this at: https://www.hillbillyu.com/kinetic-impact-explosion-crater
An impact can also appear as a smudge on an anomaly map as the Frankewing Crater does in which I live.
An impact can show up in reverse magnetic blue. Some meteors are stone and do not distribute iron but do make a blue bruising mark.
Serial impact. Some bolides come apart and cause multiple impact close to each other. This is what happened at the Flynn Creek and Dycus Imapacts in Tennessee. Once again the out of state big geology notable only investigated the one which left confusion. Not really anything systematic in that approach.
4. Presence of impactites.
Iowa Impact Spheroid Shells. Oldest on the planet. Have decayed into just shells.
Specimen above is from Linn County. It is an impactite with iron pellets, manganese, crypto crystal metamorphic chert and direction of impact record from left to right. It also has shock fractal constellationing. You can read more about that at: https://www.hillbillyu.com/constellationing
Linn County is in the quadrant shown below. While the whole state is a crater debris field it is important to note another concept. Rock migration. Impactites can travel as with glacial till as do other rocks. Rocks will move down streams or move down along slopes.
5. Karst Maps - Impact can cause karst areas and even karst rings.
Impacts and Karst Areas are relatable. While not in a blow up this big of just a county some impacts will make a circular "Karst Shadow." Shown below is the state Karst Map.
Craters can have double rings and central uplifts. Just using the Karst map alone I put down suspect craters. Now let's look at the fault map.
You get the idea. While an overlay of all these suspect crater tools would improve crater confirmation; I still like to follow the impactite trail. I also drive around and look at road cuts, construction excavations, creek beds, streams and river rocks. Alas, geologist do not perceive what an impactite is, and do not recognize impactites.
So now lets look at the Iowa Experts idea of craters in their state.
6. Fault Maps - Impact can and often does show up as faults. Is like reading an x ray for broken bones.
.jpg)
Well this is sad. It is a historic small meteorite record and is missing the Decorah Crater. The surrounding dots are likely impact breakup.
7. Fossil Anomalies - Sorry, I cannot help placing suspect crater markings on this map too.
The Decorah Crater filled with sediment which contained the largest predator at the time they presume. The fossil record however is not a snapshot of living time. It is a cemetery of the dead time. The shale in which the fossil was found is often an ash based rock from the impact explosion itself. I have even found incinerated shells in the ash bentonite here in this crater the Frankewing, TN Crater. https://www.hillbillyu.com/yankees-have-worms
species of eurypterid, Pentecopterus decorahensis. Pentecopterus was scorpion-like in appearance, and the largest predator known from that time, measuring nearly 6 feet in length. Its species name was derived from "Decorah.
8. Ores - Mining in Iowa - As a model of earth impact mining records the mineral dispersion. As Iowa is not a tectonic or mafic base the ores are impact deposits often referred to as occurance mines. As each earth impact is unique these ore deposits are specific to impacts and analysis of them shows different ages and mineral content. Here is the list by ore type:
Top Commodities
in Iowa
-
Lead (72)
-
Zinc (69)
-
Iron (8)
-
Silica (7)
-
Barium-Barite (2)
-
Cadmium (1)
-
Copper (1)
-
Molybdenum (1)
Top Counties
by Total Mines
Additionally I have circled Buena Vista County home of Sulfur Springs since sulfur is such a common content of meteorites.
9. Soils - Impact makes and changes soils. Clay is a nano product of impact. You will also see regions with soil contours as residual effects.
The Ice Sheet Push
Impact Splatter
10. Topography and Hydrology - Besides the Manson Iowa Crater being discovered by well drillers you can look for anomalies, circular features etc. on the topo and hydro maps.
You get the idea. You have several areas of Iowa with more box type drainage shapes.
Zone 1
Zone 2
Zone 3
Iowa is not really flat. This is a Lidar map of the state with anomalies circled. The Outlook company makes my favorite state topo maps, but in this case it just shows the ice sheet slide better.
11. Well Drilling Reports - Obviously Iowa has the highest resolution geology mapping I have ever seen. Is a great tribute to Van Allen. Equally obvious is the many craters under the surface of Iowa. Upper landform topology is a poor tool for crater finding.
The mineral map is better. As geology is stuck in the dark ages they do not understand that most of the surface minerals are impact deposited. The mineral map and the topo map agree as indicators.
The geology anomaly map however predicts that more minerals are buried and have not been found yet along with their associated craters.
So let's double down here. You have read this far and have nothing better to do than read an old oil geology report. You see oil, water and minerals is how you get a well sunk.
https://www.iihr.uiowa.edu/igs/publications/uploads/2015-12-17_15-12-43_pic-2.pdf
Southeastern Iowa Page 7 "A major unconformity is present at the top of the Lower Devonian with the result that Middle Devonian rocks rest upon strata ranging in age through Lower Devonian, Silurian, Upper Ordovician (Maquoketa Formation), and Middle Ordovician(Galena Formation)." The term unconformity is key. These geological wiping events are best explained by impact. You see a flood or volcanic event are more likely to deposit material than wipe it away.
Page 10 "The Pecatonica and the overlying McGregor Limestone should be considered together as the Mc Gregor contains o i 1-fi II ed fractures and vu gs . The source beds for the hydrocarbons may have been the overlying carbonacous dolomites and shales of the Decorah Formation which are called 11oil rock 11 by mi.ners in the lead-zinc district of Iowa, Illinois, and Wisconsin. On distillation the shale gives off hydrocarbons and when dry burns readily. In the subsurface these rocks characteristically contain sol id "blobs 11 of hydrocarbon." This is another case of mistaken identity in geology. These carbons are often unburned products of impact. They are like charcoal.
Water well drilling book: If you can read well drilling reports for clues about impact strata these records are available for about any state. Some things to look for:
1. Unconformities - these are almost always going to be impact caused.
2. Busted up strata - this is an energy event and need to be accounted for.
3. quartz, chert of any metamorphic. if assigning origin tectonic or impact trace it don't leave it with no provenance
4. ash, bentonite, clay are likely impact products.
https://core.ac.uk/download/pdf/61090183.pdf
Nikel iron + ?(has a green tint a trace element) impact concretion from the Manson impact. These impact instant concretions are blasted out and fall like hailstones. It is very old but as you can see it is a stable metal alloy. Is a really good find.
Keisha Hornsby · Sept. 12, 2022
Found this rock in Central Iowa. Very dense, not very big. After I cleaned it, it had a shimmering look to it. It glimmered like it had gold paint on it, depending on the lighting. I decided to break it open, but I still can't tell what it is. In all the tons of rocks my husband and I have brought home from all over the state of Iowa, we've never had one look like this. A magnet does not stick to it. And the inside of it feels like graphite or reminds me of pencil lead. Maybe it's nothing special, but it had me curious.
Soil maps show the soil as impact material and are still banded around the impacts, subject to some surface movements like the proposed glacier movement in Central Iowa.
Now here is a macro key to impact origin a shift skip of strata layers. Jumps past the normal strata sequence order are unconformal.
Surface minerals are always suspect impact distributed. Any mining circle is a likely impact. Randon map is a by product of uranium decay. And lets face it most impacts are very old.
.jpg)
I believe this to be a specimen from a "Shock Floor." This would be the surface produced by the spreading shock wave from a large earth impact.
Jon Wait specimen from Parkersburg, Iowa. USA
Very old meteorite or impactite. Weathering, can it remove the smooth cavitation surface? Was it made with rough cavitation? Possible, as if it is an impactite the impact gas environment would not be oxygen.
Ken Jackman · · Oct. 9, 2022
I thought I had posted this earlier but don’t see it so if it is a duplicate I apologize. Object is believed to have been retrieved from a field in late 1800’s in Iowa. Weighs 9.5 lbs and magnets are attracted to it. Do I have a meteorite here?
I believe this to be a specimen from a "Shock Floor." This would be the surface produced by the spreading shock wave from a large earth impact.
Jon Wait specimen from Parkersburg, Iowa. USA
Shock agate. Not a radial body type, this one is directional. Feb. 7, 2024.
Collecting Lake Superior Agates
Leon Herold · ·
3 lb 7 oz Iowa find
The big NW Iowa Subduction Crater, a type 2. June 18, 2024.
Impact made blast surface from the Manson Iowa Crater. While you could be about 40 miles from Manson Impact center and it is reported to stretch out about 12 miles in your direction, crater sizes are often under reported. Take for example the Chegg Products & Services geology anomaly map. It shows the crater complex or system of connecting craters. to be much larger and continuous with where you found this specimen. See Attached. June 18, 2024.
Anesa K McGregor · ·
This rock was dug from the bank if a creek in northwest Iowa, palo Alto County. I have been trying to find out what the identification could possibly be. It was pulled up with a loader on a tractor and is so heavy it almost pulled the tractor over. It has what looks like rust in places but it us out magnetic. Also the spaces do not go through. Any ideas?
