Figures 12 and 13 make clear that Iran had made the most progress on seismic methods to measure the yield, where by the time of the slide, it assessed it was 30 percent finished. Project Amad likely had help on developing seismic methods, since Iran is in an earthquake zone and had built extensive skills and experience in seismology. The open literature on seismic methods for yield predictions was also much more extensive than that of the other methods discussed here, partly because of the work surrounding the development of verification methods for the Comprehensive Test Ban Treaty. This work was quite detailed and discussed openly in the literature and at government fora focused on the CTBT and its verification.

Beyond the theoretical seismological work mentioned in Figure 13, Iran also conducted seismic experiments using high explosives. A title page of a document related to preliminary work to develop seismic detection methods to predict the explosive yield is shown in Figure 16.

Figure 16

Archive document on developing yield estimates via seismic methods.

Translations of title page, from top to bottom: ‘In the name of God,’ ‘Analysis for the Yield Estimate of Explosions in Well Number 1, 2, and 3 of the Pour-Midani Project’ [Note an alternative spelling is Poor-Meydani], ‘Report number 1,’ ‘Abdolrahim Javaherian riyan’ [Note: author or subproject leader], ‘May 2003’

The author listed on the document is Abdulrahim Javaherian riyan. There is an Abdolrahim Javaherian, Ph.D, who is currently Professor of Geophysics, Department of Petroleum Engineering at Amirkabir University of Technology. A literature search by Mark Gorwitz produced an extensive number of his scientific publications on seismology.

The tests involved the detonation of three high explosions, ranging from 0.5 to 4.62 tons of TNT. Figure 17 is a page from this report that has the locations, dates, and times of high explosive tests in what are called wells 1, 2, and 3.

Figure 17

Page from report in archive on high explosive tests showing the time, location, and magnitude of a high explosive test on February 6, 2003 and two tests on April 17, 2003.

Figure 18 shows the locations of the Pour Midani high explosive tests in Iran and the area of the Chah Shirin mountains. Their location is near the Semnan Space Launch Center, which was built soon after these high explosive tests.

Figure 19 contains two ground photos from the archive of the area of one of the high explosive tests, which consists of an alluvial plain in this very remote area of Iran.

Figure 20 shows the location of the high explosive tests relative to the five potential underground nuclear test sites.

Figure 21 correlates one of the ground images with 3D terrain on Google Earth, which is observed when the cursor for ground-level view is placed on the coordinates given in the Nuclear Archive. This supports that the ground photos were taken, and the tests were conducted, in close proximity to the provided coordinates.

Figure 18

Location of the high explosive test sites near the Chah Shirin mountains.

Figure 19

Two archive images from the area of the Pour Midani high explosive tests.

Figure 20

The location of the high explosive tests relative to the potential nuclear test sites.

Figure 21

Correlating one of the ground photos (top) to Google Earth 3D perspective terrain of the area generated from the Nuclear Archive document’s geo-coordinates (bottom).

Figure 22

Archive images of high explosive tests. High explosives in upper left image. High explosive shaft (upper right). Possibly fill material for the shaft (bottom left) and capping it with a concrete plug, prior to detonation (bottom right).

The seismic high explosive experiment involved placing the high explosives down a shaft. The shafts were 30 meters deep. Figure 22 shows four ground images from the archive of what appears to be the preparations for a below-grade high explosive test.

After the detonations, seismic waves propagated outward were recorded at local seismic stations. Overall, Iran appears to have well documented the high explosive events. The Iranian report (Figure 17) states that the explosions were detected at a few local seismic stations up to a few hundred kilometers from the blast. The Iranian document on the high explosive tests states: “In reports 8, 9, and 10 details of recorded detonation waves by these noted networks are documented.” These reports appear to be the same ones listed in the table of Project Midan reports in Figure 13, bullet 12, which have to deal with “recording waves produced by detonations.” Obtaining access to these documents could be helpful in follow-up efforts to investigate this issue.

It is not surprising that several stations, as distant as Esfahan, recorded the explosions, particularly the largest test. Figure 23 shows a recent map of the many seismic stations in Iran, where the general location of the high explosive tests is marked on the maps.

Figure 23

Seismic stations in Iran overlain on Google Earth images. The top image shows a recent map of Iran’s seismic network and the location of the high explosive tests and the five potential underground nuclear test sites. The bottom image is a map of seismic networks of the Iranian Seismological Center. Map © Cartography Division of IRSC, by M. Dezvareh, September 2015. The inset encircles in red the seismic networks listed in the Nuclear Archive that picked up the 2003 explosive tests, which were part of preliminary experiments under Project Midan: Semnan, Tehran, Esfahan, and Mazandaran (Sari is in the Mazandaran province).

The Institute also looked for seismic evidence of these explosions outside of Iran. The closest non-Iranian station was in Turkmenistan at a distance of about 500 kilometers from the blast points. Seismic events are recorded on the websites of the International Seismological Center (IDC) ( http://www.isc.ac.uk/iscbulletin/search/catalogue/ ) and the U.S. National Earthquake Information Center (NEIC)

(https://earthquake.usgs.gov/earthquakes/search/). However, these data do not indicate any seismic event that could be associated with these three explosions.

This result is not surprising given the distances to the nearest station outside Iran, the geology, the time of the day (high noise), and the presence of standard seismic equipment not specialized in detecting high-frequency signals from local explosions. In any case, the Iranians were likely conducting these relatively small yield tests to see how the detonations would record locally.

Since 2010, the CTBTO, the implementing arm of the CTBT, has operated a high capability array station, Alibeck in Turkmenistan, 500 kilometers from the Iranian test site. This array would be expected to provide excellent coverage.

Google Earth and Bing did not have any high resolution images of the area of the high explosive tests near the time of the tests in 2003. We obtained September 9, 2016 and March 15, 2018 images from Digital Globe to try to see any lingering evidence of the tests. Part of the motivation for obtaining imagery is that tracks in the desert can last for decades.

However, the high explosive tests were conducted in the vicinity of the Semnan Space Launch Center, more officially called the “Imam Khomeini Space Center (Semnan).” Construction of this launch center reportedly started in 2003 and it continues to operate. Further complicating our analysis, in the images, we identified another area near the Space Center and closer to the location of the Project Midan high explosive tests, which we call the “Semnan Military Proving Ground,” an area for conducting a variety of testing of military explosives and mobile missile systems. We could not find any public record of such a military proving ground located east of the Semnan Space Launch Center, making this identification the first public one (see Figure 24 and Annex 2).

Figure 24

Overview of test site locations, the Semnan Military Proving Ground, and the Semnan Space Launch Center.

We believe that we have identified the location of the first nuclear related high explosive test (0.5 tons of high explosives or HE) as a circular mound of disturbed earth located at the precise location given in the Nuclear Archive document, “Analysis for the Yield Estimate of Explosions in Well Number 1, 2, and 3 of the Pour-Midani Project” (see Figure 17). This location looks the same in both the 2016 and 2018 images (Figure 25). However, we could not discount changes earlier than 2016 and following such a test in 2003.

The second site (reportedly involving tests with 4.62 and 2.15 tons of high explosives) could not be confidently identified. Nonetheless, areas of ground scraping could be identified at the end of a vehicle track that begins at an improved road and is within 200 to 300 meters of the geolocation given for the second and third nuclear related tests (Figures 26 and 27). The fact that additional new ground scraping has taken place after 2016 is evidence that the area is still being used as part of what we have labelled as the Semnam Military Proving Ground. A small possible camp or support area remnant can also be observed located about 650 meters north of the Nuclear Archive’s geolocation for the second and third high explosive tests (Figure 27).

Figure 25

Possible location of first high explosive test on February 6, 2003.

Figure 26

Area of second and third high explosive tests.

Figure 27

Geolocation of second and third high explosive tests and their correlation with ground imagery from the Nuclear Archive and recent commercial satellite imagery.

Comparison of the terrain in the ground photos of the Project Midan high explosive test activities provides excellent correlation with what can be observed at the geolocations on commercial satellite imagery of the site and in perspective views generated with Google Earth, leaving no doubt that the geolocations of the nuclear related high explosive tests found in the Nuclear Archive are quite accurate (Figure 27). Despite the thirteen plus years since the high explosive tests occurred in early 2003, using what high resolution imagery was available, we do believe that we were able to locate the first test site, but we are not confident that the second and third test site(s) can be similarly located.

Each test area of the Semnan Military Proving Ground has its own dedicated bunkered structure, probably for fire control and diagnostics located along the improved road at various intervals from one to three kilometers apart. As can be seen in Annex 2, we have identified two high explosives test areas and two “probable” missile test launch sites. The Iranians utilized two such test areas further east along the improved road, where the geolocations in the chart place the high explosive test locations about 1.2 kilometers directly south of the improved road where a bunkered structure is present.