Tektonik Pothole

The Tektonik pothole is among the specially protected caves of Hungary. It is located in the Aggtelek National Park area. Together with the other caves of the Aggtelek Karst and the Slovak Karst, the cave has been part of the World Heritage since 1995. It is the eighth deepest cave of the Aggtelek Karst. It is one of the six specially protected caves of Bódvaszilas.

Description

On the Upper Mountain plateau, about 960 m from the peak of Vecsem-bükk, in the sinkhole named Bak Antal, whose namesake lived in the 18th century, the entrance of the Tektonik pothole opens. It is the fourth deepest pothole of the plateau. About 70 m from it, roughly 25 m higher, the Moszkitós pothole opens. From Bódvaszilas, one must travel 2 km following the blue cross sign, and when almost reaching the edge of the plateau, the first sinkhole beside the path, on the east side of the Bak Antal sinkhole, is the entrance of the Tektonik pothole. The cave’s location is marked on tourist maps.

In the highly protected nature reserve, in a forest, at the foot of a 0.5 m high rock overhang, there is a hard‑to‑notice broken cave entrance, a narrow fissure measuring 1 × 0.5 m with a vertical orientation.

The cave formed in middle Triassic limestone along tectonic fault lines. The cracks were enlarged by underwater dissolution, seeping waters and, to a lesser extent, collapses. It did not function as a water sink. The thoroughly surveyed cave is 350 m long, 80 m deep, with a vertical extent of 80 m and a horizontal extent of 45 m. The vertical extent is characteristic of the cave. It consists of several parallel shafts. Its structure is labyrinthine, similar to the Szabó‑pallagi pothole, but the shafts are narrower. The shafts are not connected stepwise but are linked by fissure‑aligned openings.

Its terminus is a fissure filled with rock debris. Finger-like stalactites, as well as pendant dripstones, flowstone dripstones, stalactite poisoning, typical (spherical) pea stone and large calcite crystals formed in the cave at the place called Giant Calcite. Bats occur in its passages. The fill contains guano and bat bones. Sometimes large animals fall into it and die. The unsealed pit can be visited with a permit, using rope‑technical equipment and good physical fitness.

The cave occurs in the literature under the names 59 (Kósa 1992), L‑1 (Kósa 1992), Tektonik Shaft (Takácsné, Eszterhás, Juhász, Kraus 1989) and Tektonik pit (Csernavölgyi 1974) and designations. The pit received its name from the discovering VMTE Tektonik Cave Research Group. In 1977 the cave was first called Tektonik pit in the literature (Kordos 1977).

Research history

In 1973 a member of the VMTE Tektonik Cave Research Group discovered and explored the cave, which at the time was thought to be 78 m deep. According to the compilation published in 1977 in Karst and Cave, on 31 December 1977 Hungary’s 32nd deepest cave was the Tektonik pit located in the Aggtelek Karst, 76 m deep on 31 December 1977, with unknown depths in 1976 and 1975. This compilation is more up‑to‑date than the list published in the May 1978 MKBT Invitation. In the June 1978 issue of the MKBT Invitation it was published that the Tektonik pit on the Aggtelek Karst, omitted from the list titled “Hungary’s deepest and longest caves”, has a depth of 76 m according to László Lukács.

At the 1982 National Hiking Meeting of the Hungarian Karst and Cave Research Society it was one of the hiking destinations. The book *Caves of Hungary* published in 1984 does not mention the cave, nor is it listed in the national cave list. According to the status as of 31 December 1987, Tektonik‑zsomboly, with a vertical extent of 76 m in the 5450 cave‑cadastral unit, is Hungary’s 38th largest cave by vertical extent. According to the compilation, the depth list published in *Karst and Cave* in 1977 records the cave at a depth of 76 m.

In the special 1989 issue of *Karst and Cave* a English‑language study (The caves of Hungary) was accompanied by a list of Hungary’s deepest caves. According to the list, the 76 m deep Tektonik‑zsomboly (Tektonik Shaft) lying in the Aggtelek Karst was Hungary’s 38th deepest cave in 1988 (the cave was also 76 m deep in 1977). The BEAC Cave Research Group surveyed the shaft. Measured along the cave’s polygon the length is 140.85 m, the depth 77.35 m, and the horizontal extent 14 m. An approximately 100–120 m side tunnel was not included in the polygon length. During the mapping of the cave in 1990–1991 new sections were discovered by climbing the still‑unexplored chambers. Attila Nyerges drew in 1990 the plan‑section maps of the Tektonik‑zsomboly, the Main‑well cross‑section maps, the Entrance‑well cross‑section maps, the east‑west projected longitudinal section map and the partial plan map of the cave. Attila Nyerges compiled in 1991 the cave’s three‑dimensional, i.e., isometric map and the plan projection map.

The geographical location of the pothole is shown in the figure published in 1992 in Karst and Cave, which presents many of the Lower Mountain's Hungarian part, its potholes and sinkholes. Attila Kósa first published the cave's projected longitudinal section map made in 1991 and the planimetric map made in 1991 in his book published in 1992. The geographical location of the cave can be observed on one of the maps showing the Hungarian side of the Lower Mountain plateau. Together with several data three literary works dealing with the cave are listed. The longitudinal section map differs from the planimetric map drawn in 1991. On the published map the depth of the cave's deepest point is 77.3 m, on earlier maps 80 m. The cave was one of the trekking destinations of the international speleology camp organized by the MAFC Cave Research Group, held between 27 December 1994 and 1 January 1995. The Tektonic pothole has been part of the World Heritage since 1995. According to the thesis prepared by Attila Nyerges in 1997, the 80 m deep Tektonic pothole is the 6th deepest cave of the Hungarian part of the Lower Mountain.