DHAMTARI SINKHOLE
20.708300,81.558300
Description
An allegedly »giant sinkhole« (ADYALKAR et al. 1973, 1980) in the shape of an elongated ellipse (up to 14 km by 8 km wide and 60 m deep), which covers an area of about 88 square kilometres, actually consists of an in-filled syncline buried under a cover of Quaternary alluvium (sand, clayey sand and clay with kankar) draining intra-alluvial percolation waters. SITUATION: Near the town of Dhamtari (note 1) in the Raipur basin and in the triangle (note 2) between the left (west) bank of the river Mahanadi and the right (east) bank of the Kharun (note 3). Geologically, »this sinkhole … [is formed] at the contact of the Chandrapur sandstone and the Charmuria limestone« (ADYALKAR & RAMANNA 1980: 49). DESCRIPTION: »The shape of the sinkhole is … controlled by the trend of the major structural joints and the strike of the Purana formation. …The Kharun river has a discharge of nearly 100 klpm [1667 ltr/s] during the summer peak, which is about ten times the flow of the Mahanadi in the same period. This has now been attributed to the karstic resurgences with sources in the buried giant sinkhole [note 4] of Dhamtari« (ADYALKAR, PHADTARE & RAMANNA 1973).
NOTE 1: Dhamtari N20°42': E081°33': 326.8 m asl (Everest 1830) on Survey of India sheet 64-H/10 (edition 1980).NOTE 2: ADYALKAR et al. (1973, 1980) position the »Dhamtari Sinkhole« between N20°40': E081°27' and N20°48': E080°49' (unspecified geodetic datum probably Everest 1830) and thus some 10 km to 20 km south-east of the Kharun / Kharua River. NOTE 3: Kharun River joins near N21°34': E081°39' (WGS84) the river Seonath, the »Kharua River« on AMS sheet NF44-11 Raipur (U502 series, 1960 edition) and »Karun« on the India Road Atlas (Eicher Goodearth 2006: 73 G5. NOTE 4: It may have slipped from the attention of ADYALKAR et al. (1973, 1980) that "karstic resurgences" do not rise from alluvium but resurge from karst, which is: »A landscape created on soluble rock with efficient underground drainage. Karst is characterised by caves, dolines, a lack of surface drainage and other climatically controlled features …« (LOWE & WALTHAM 1995: 21).
Caves nearby
| Distance (km) | Name | Length (m) | Depth (m) |
|---|---|---|---|
| 51.3 | BHATGAON BLEBBY CAVE | ||
| 51.3 | BHATGAON BOREHOLE CAVES | ||
| 53.6 | NAWAGAON SINKING, Mangalore River | ||
| 54.2 | SARGI RESURGENCE, Rajim | ||
| 58.9 | KHARUN KARSTIC RESURGENCE | ||
| 59.9 | RAIPUR ARTESIAN SPRING | ||
| 62.3 | SIRIKALAN SINKING, Sukha River | ||
| 87.9 | KHARORA ARTESIAN SPRING | ||
| 94.1 | KAUADIH |