Tatabányai Bányász Cave

The Tatabányai Bányász Cave is one of those periodically operating characteristic water-absorbing caves, which is located in the Gerecse Mountains in the Danube–Ipoly National Park. Bats also occur in its passages.

Description

In the valley between Kő-hegy and Halyagos-hegy in the Gerecse, in the Kis-rét area, on the outskirts of Tatabánya, at about 300 m above sea level, the cave has a vertical entrance axis and a steel‑plate door. Near the busy tourist trail marked with a red stripe that runs along the eastern edge of the Kő-hegy plateau, there is the opening whose bottom opens.

The dismantled entrance shaft is 1.5×1.5 m in cross‑section. The almost vertical shaft is 1–2 m in diameter and 7 m deep. From the bottom, a passage continues with smaller steps and connects at a depth of 12 m to the ceiling of a chamber. The very steep lower chamber is 9–10 m long, 2–4 m wide and 4–12 m high. The periodically active water‑absorbing cave was formed along the thick‑bedded limestone Triassic EÉK–DDNy‑oriented fault line by the dissolving action of infiltrating waters. Its walls are finely corroded and free of formations. The lower part is always moist, but drips are rare. It can be visited with the permission of the Danube–Ipoly National Park Directorate.

The Gerecse Cave Research and Nature Conservation Association carried out bat observations in the Tatabányai Bányász Cave, during which they identified 2 bat species; the lesser mouse‑eared bat and the common bat, among the group members. Based on the few data available so far, the cave can be considered a conditionally small‑species‑ and individual‑number winter bat roost.

In 1981 the cave was first called Tatabányai Bányász-cave in its literature. The cave appears in its literature under the names 7-8. water sink (Székely 1994), 7-8. water sink (Juhász 2007), 7 water sink (Sashegyi 1972), 7 water sink (Sashegyi 1972), 7 and 8 water sink (Lendvay 1979), 7 water sink (Juhász 1994), Bányász-cave (Lendvay 1975), Csemetekerti water sink (Lendvay 1979), Csemetekerti-water sink (Székely 1994), Kisréti water sink (Lendvay 1979), Tatabányai-Bányász-cave (Lendvay 1975) and tatabányai Bányász-cave (Kordos 1984).

Research history

In 1964 the 2nd section research group of Vasútépítő Törekvés broke through this seasonal cave, in which the members observed encouraging air movement, but encountered a collapse. There was no time and energy for further development. In the spring of 1965, during field surveys, several small water sinks were recorded, one of which is located near the Turul. The Vasútépítő Törekvés cave explorers knew it under the names Csemetekerti water sink and Kisréti water sink. They planned to develop it in 1966, but this did not happen due to the group leader’s military service. According to the group report published in the 1966 Karst and Cave Research Bulletin, at the end of March and beginning of April 1965 the group members began field surveys on the Gerecse side facing Tatabánya, during which they found several small water sinks. The most encouraging among the found water sinks is near the Turul monument. This water sink is artificially filled by the forestry service.

In the first days of 1972 the Tatabányai Szénbányák Barlangkutató Csoport continued the investigation of the 7th water intake, partially explored in 1971. The group's 1972 report states that the intake is inactive for most of the year, operating only during particularly heavy showers. It is equipped with a bolt to prevent collapse of its square mouth. The opening gradually widens downward, reaching a diameter of 1.5–2 m after a few meters. At 9–10 m there is a steep and narrow funnel, which is 5–6 m long. A small ledge is found at a depth of 16 m. From 16 m onward on the D side, a vertical, wooden ladder attached to the clay ledge reaches the floor at a depth of 25 m. A fissure formed along the bedding plane is 14 m long, 15 m high and 3 m wide. The chamber sloping toward the EK is filled with debris, its lower part filled with clay. In 1972, trial drilling advanced the members about 3 m forward. Further exploration was hindered by the small team size and insufficient equipment.

In 1975 the Fényes Elek Barlangkutató Szakosztály surveyed the cave during the spring camp and at that time set up a meteorological station at the end point. A photographic documentation consisting of black-and-white photos and color slides was completed. Its entrance, which was very collapse‑dangerous, was cleared in the second half of the year, allowing exploration to begin at the deepest point of the cave. The works were led in the first half of the year by Lendvay Ákos and Doronyai József, and in the second half by Szécsényi László and Hermann Béla.

In 1976 the Kőbánya Cave Exploration and Mountaineering Section worked in the cave during the spring camp and then on three‑day work trips. According to the Section’s 1976 report, the deposition of a large amount of debris is hazardous, therefore the members’ first task in 1977 was to open a new entrance. The cave air temperature was measured at three locations. Two tables showing the results of the meteorological measurements were published in the 1976 MKBT Report. The old scaffold was in such poor condition that it had to be dismantled and carried out of the cave because of its danger. At the deep point a demolition was started in a 120 × 120 cm section. A new scaffold was built, but after the insertion of the second member of the frame a collapse occurred. At that time the researchers were working at a depth of about 3.5 m. The debris accumulated in the very steep chamber slipped and, falling through the insufficiently high scaffold, fell onto the demolition site.

No personal injury occurred, but some of the tools remained under the debris. Work can only continue if the collapse‑dangerous entrance is sealed and a new entrance is opened. There is an opportunity to open a new entrance and the excavated debris must be brought to the surface through it, because it is not advisable to accumulate it in the steep chamber. The Section’s 1977 report states that securing and filling the very collapse‑dangerous cave in Turul Forest was an urgent task for the Section. The researchers led by László Szécsényi closed the dangerous part at several places and, because of hikers, blocked the entrance.