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I have been examining Sentinel-2 multispectral imagery of an area located on the island of Borneo in Indonesia near 0.04918° S, 116.530° E with an area of 38.60 km2 - 8.46km by 6.65km

link to mapping

The landscape shows a circular to elliptical pattern approximately 4–6 km in diameter with multiple concentric rings visible in:

  • SWIR moisture-sensitive bands
  • NIR vegetation response
  • visible bands under contrast stretching
  • several different index combinations

Observations:

  • The rings remain stable across different dates and seasons.
  • They appear in SWIR bands that are less affected by vegetation, indicating possible subsurface or soil-property differences.
  • The pattern does not follow river channels, drainage lines, fire scars, or known land-use boundaries.

The polygon of the location:

{"type":"Polygon","coordinates":[[[116.548891,0.077848],[116.550951,0.075188],[116.554041,0.074759],[116.559019,0.071068],[116.559362,0.067205],[116.564426,0.05476],[116.564856,0.042315],[116.562366,0.036049],[116.557388,0.035105],[116.556616,0.029097],[116.55138,0.023947],[116.530952,0.016565],[116.480827,0.052099],[116.533184,0.081882],[116.540222,0.079136],[116.548891,0.077848]]]}

Here's the original vegetation satellite imagery

Vegetation Map

I'm also providing you with NIR, SWIR and visible Red band combined imagery

NIR, SWIR and visible Red band combined imagery

Area

enter image description here

Elevation shadow

enter image description here

Fin scale

enter image description here

Question:

What natural processes are known to generate kilometer-scale circular or multi-ring patterns in tropical lowland environments, particularly in areas mapped as peat or swamp, and what data types (DEM, SAR, geological maps, peat-core data, etc.) would help distinguish between the possibilities?

What classes of geomorphological or geological processes (e.g., peat-dome hydrology, subsurface structure, paleo-lake basins, compaction features, buried geomorphology, etc.) can produce such a pattern, and which datasets would be most appropriate to analyze next?

Is there any particular information available on this formation as I'm unable to find ANY references online?

[P.S. I'm not a specialist, so excuse me for possible mistakes]

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    $\begingroup$ Aliens? Just kidding... Some kind of water recession marks maybe, like this picture? Each ring would represent a former level of a paleolake. Just a wild guess. $\endgroup$ Commented 2 days ago
  • $\begingroup$ Could be, but the surrounding area must have undergone significant changes if the original elevation was 100 meters above current sea level. Still doesn't explain the shape (to me). Can not know for sure $\endgroup$ Commented 2 days ago
  • $\begingroup$ A description of the surrounding area says it is large forested peatland with seasonal inundation during the first quarter of the year. In terms of human uses there appear to be herb collection, small scale logging, and catching of freshwater fish, with the latter being a major economic factor in the area, leading to the digging of canals and ditches. If this is a natural feature, a seasonal lake seems a possibility? If man made, could it be a concentric system of ditches (seems highly speculative and far-fetched, though). $\endgroup$ Commented 2 days ago
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    $\begingroup$ @Number16BusShelter I assume by "legal status" you are referring to a nature preserve or some such (it isn't mentioned in the question, unless I overlooked it)? How long has the current legal status been in place? Have you tried to retrieve older satellite imagery (from the 1980s, say) for comparison purposes? $\endgroup$ Commented 2 days ago
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    $\begingroup$ We would just like to know, have you tried to retrieve older imagery for comparison purposes? A look at older imagery shows this pattern does not fully exist. Tell us what you have found or think this could be. Imagery clearly shows evidence that this is a developed and surveyed area (roads, fence lines, fields). Perhaps you have some interesting ideas to add. We are clueless, too, but the concentric aspect might indicate managed land clearing and/or resource harvesting (logging). The Copernicus link you provided was helpful. $\endgroup$ Commented 2 days ago

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