A Pinge ([ˈpɪŋə], plural: Pingen) or Binge ("binger") is the name given in German-speaking Europe to a wedge-, ditch- or funnel-shaped depression in the terrain caused by mining activity. This depression or sink-hole is frequently caused by the collapse of old underground mine workings that are close to the Earth's surface. Unlike natural landforms, a Pinge is a direct result of human activity. The term has no direct equivalent in English, but may be translated as "mining sink-hole", "mine slump" or, in some cases, as "glory hole".
Origin of the word
In the original sense of the word, the mining terms Pinge or Binge go back to the activity known as pingen which meant something like "prospecting". An aufgepingter lode was one near the surface of the ground. The Pinge was therefore like a primitive, open pit mine.
Subsequently, the term was transferred to the funnel-shaped depressions that formed at the surface above filled or collapsed mineshafts. In lode mining, shafts and pits followed the strike of the lode and left behind the typical lines of Pingen (Pingenzüge) associated with medieval mining that may still be seen, for example, in the Thuringian Forest, the Upper Harz Mountains, the Ore Mountains and the Eschweiler area in central Europe.
Later on, the term Pinge was applied to many kinds of depression left in the terrain as a result of mining activity, including the holes left by opencast pits in surface mining or the cave-ins above underground mines. The latter occurred either as a result of the unexpected consequences of active mining (often associated with accidents or disasters) or the subsidence above abandoned mines. They were sometimes willingly and knowingly accepted, for example, when mining was carried out by a method known as block caving.
A Pingenzug is a row of several Pingen in succession.
Types
A Pinge can arise in different ways. In some cases it is caused by surface excavation. In other cases it follows the extraction of mineral deposits at a shallow depth and the associated collapse of the overburden that can result in subsidence at the surface. Pingen caused by surface mining generally date to the 16th and 17th centuries and are mostly only 0.5 - 1 metre deep. Deeper Pingen, caused by collapse of the overburden, date to the 18th and 19th centuries. The Pinge, which is caused as a result of the subsidence of the surface of the terrain, is usually surrounded by a ring-shaped mound (German: Halde). A number of Pingen form trenches up to 250 metres long and 15 metres wide.
Excavation
Initially, the extraction of ore or coal took place near the surface at outcrops of the main deposits. Excavations of seam-like deposits were carried out by digging out bowl-shaped depressions, the so-called Pütts, that miners hewed out along the course of the seam with picks and shovels. Once digging reached the water table, groundwater ran into the hole. If the quantity of water was so great that it entered the pit faster than it could be drained, the holes filled up with groundwater. To make matters worse, the ingress of water and the consequent softening of the soil reduced the stability of the side walls. For this reason, the pit was simply abandoned in such cases and a new one dug some distance away. Over the years, these hollows became Pingen. In the southern Ruhr, there are numerous such Pingen caused by surface mining. Subsequent erosion and collapse has produced funnel-shaped hollows, the Pingen. Where Pingen have resulted from surface mining, small ring-shaped tips were often made by dumping the waste rock.
Another origin of Pingen occurred in a method of lignite mining called Kuhlenbau or "pit mining". Here, the brown coal was extracted by means of small, square, open pit known as a Kuhle. As one pit was exhausted, it was filled with spoil from the next. In this way, a row of several hollows or Pingen was created.