The official case file, classification D. Describes the sighting, the gendarmerie's and GEPAN's sampling, the soil and plant results, and concludes the cause could not be determined. Links the scanned original documents.
“Un phénomène important inhabituel s'est produit ce jour là, et l'enquête n'a pas permis d'en déterminer l'origine.” source
In French; summarised in English. The date is the page's last update; case number 1981-01-00849.
OFFICIALGEPAN, Centre National d'Études Spatiales (CT/GEPAN-00013) · 1983-03-01
GEPAN's full technical report: the timeline of the inquiry, the witness interviews (the witness is anonymised as ‘Monsieur C’), the soil analyses by several laboratories, the INRA plant biochemistry, and a cautious conclusion.
“Ainsi une enquête comme celle que nous venons de présenter pose plus de questions qu'elle n'apporte de réponse” source
Scanned document with an OCR text layer; quotations checked against that layer.
OFFICIALBiochemistry laboratory, Institut National de la Recherche Agronomique (INRA), for GEPAN · DATE TO VERIFY
The plant-analysis file published by GEIPAN. According to GEPAN's note 16, it found pigment losses of 30 to 50% in leaves nearest the trace, correlated with distance, and raised an intense electric field as a possible cause.
Image-only scan; its text could not be read in this session. The summary follows GEPAN note 16 and the GEIPAN case page.
The gendarmerie report published by GEIPAN. According to GEPAN's note 16, the gendarmes recorded the witness's statement on 9 January and described two concentric circles of 2.20 and 2.40 metres in diameter.
Image-only scan; its text could not be read in this session. The summary follows GEPAN note 16, which quotes the report.
GEIPAN's own history and classification: GEPAN created in 1977, SEPRA from 1988, GEIPAN from 2005. Category D means an observation unexplained despite the information GEIPAN holds.
CLASSIFIEDDeclassifiedFILE NO. 011SHEET 2 OF 2
Analysis
Our own reading of the file, written from the sources on the other sheets. Opinion is marked as such.
Trans-en-Provence is famous because something was measured. Gendarmes sampled the ground the day after; laboratories found compacted soil, traces of iron, phosphates and zinc, blackish residues and heating below 600 °C; a biochemistry laboratory at INRA found damage in alfalfa that grew with proximity to the trace. All of it is published by a state agency, which is rare.
The weak points are just as documented. There is one witness. GEPAN arrived forty days later, after heavy rain, on a site that sceptics say had been trampled by visitors. The gendarmes' first description compared the marks to skidding tyres, according to the sceptics' reading of the file. The plant results came from a single laboratory and their cause was not determined. GEPAN's own conclusion is careful: a sizeable event happened, and the analyses do not confirm what the witness described.
Our label is Unexplained because the official body investigated and reached no conclusion on the cause. It would move to Explained if the tyre or vehicle hypothesis were tested on the original samples and photographs and it fitted.
What it shows
That France's official UAP office investigated a landing report with soil and plant analyses by several laboratories, and published the results and the original documents.
That the laboratories found real changes at the trace: compacted soil, metal and phosphate traces, blackish residues, heating below 600 °C, and plant damage correlated with distance.
That GEIPAN still classes the case D: unexplained despite the information it holds.
What it doesn't prove
That a craft landed. The account has one witness, and GEIPAN says the analyses give no proof of it.
That the trace was made by the object described. GEPAN called the possible interpretations too diverse and vague to confirm the account.
That the plants were exposed to an unknown energy. The cause of the damage was not determined; an electric field was only a hypothesis.
The other side
Sceptics argue the case was never unexplained, only under-investigated. GEPAN came forty days late, after heavy rain, to a site walked over by onlookers, journalists and amateur investigators. The marks were two separate arcs, not a ring, and the gendarmes likened them to tyre skids; the black residue's components (carbon black, zinc, phosphates) match tyre rubber. A car turning on the path was never ruled out. The story began with a neighbour keen on UFOs, and the witness later made remarks that sound like an admission. On this reading it is a small joke that grew.
A detailed sceptical critique of the GEPAN inquiry: late intervention, a trampled site, tyre-skid marks, a tyre-like black residue, problems with the plant analysis, and a reconstruction of the case as a joke that got out of hand.
“L’hypothèse que les marques observées aient pu être produites par les roues d’un véhicule automobile, qui auraient ripé à plusieurs reprises lors de manœuvres de demi-tour, n’a donc jamais pu être sérieusement réfutée.” source
Chapter of the preliminary online version of a book later published by book-e-book.com (December 2007). Sceptical commentary, not an official finding.
TO VERIFY Candidates, not yet checked
The INRA plant-analysis file and the gendarmerie report (PV n° 28) on cnes-geipan.fr are image-only scans; their text was not read directly. Exact dates and wording to be checked by eye.
Other documents on the GEIPAN case page (ALAT, Météo, SNEAP, LDP and DER analyses, photographs) were listed but not opened.
Jacques Vallée, ‘Return to Trans-en-Provence’, Journal of Scientific Exploration (1990): not opened.
Michel Bounias's 1982 INRA–CNES contract report on the alfalfa (cited by the sceptics): not opened.
The witness's 1989 television remark and the mayor's comment quoted by the Observatoire Zététique: secondary quotations, original broadcasts and articles not found.
The witness's name is widely published; GEIPAN's file anonymises him. Editor to decide whether the archive names him.
Found, but not linked to a source we trust. Not on the sheets until they are.