Cave Rocky Relief And Its Evolution Of Old HuangLong Cave

Factors shaping the karst underground leave the traces on the rocky perimeter of the caverns. The associated rocky features are rocky relief. In domestic we also call it as cave corrosion feature, cave microtopography, speleogen, or small cave feature. The relief is frequently an important speleomorphogenetical indicator and, as such an indispensable component of interdisciplinary speleological researches. With large cave shape, the rocky relief is an important indicator of the study of cave development evolution, the analysis of hydrological characteristics and hydraulic conditions. Rarely is their development explained, but there is no series of studies of rocky relief as a speleogenetical indicator.This paper takes Kunming Old Huanglong cave as the research object. Through the observation of the old Huanglong cave rocky relief, such as in indoor data collection, field survey, observation and measurement, taking pictures, and analysis of the causes these rocky relief, we have several conclusion as follow:1. The general trend of the passage is east-west direction. The direction of the passage is controlled by the nearly transmeridional fault at the carbonate area. Through the comparison of the Rose diagram of Structural fracture and the Rose diagram of passage in Old HuangLong Cave, we can find that the direction of the structural cracks and the direction of the tunnel are broadly consistent.2. The rocky relief in old HuangLong Cave is rich. We measured the total of 66 case points. There are five typical features be found in old Huanglong cave, respectively flow mark, corrosion tube, pothole, notches and bulge. The types of flow mark and pothole are the most and they distributed in the whole cave, and other typical features are distributed in the last half.3. At the type of flow mark, what we relatively easy to identify is waving flow mark that it is formed by the combined action of erosion and corrosion. The formation of pothole is connected with joint corrosion on the condition of subsurface flow. The flow corrodes the joint, and then produces a vortex perturbation to make the rock be eroded. The generation of corrosion tube is related to the hydrological conditions. Its formation due to the state of full charge in the limestone at the upper part of the sand shale, and dissolve the limestone along the crack. The type of notches are all transformed by the sediment in the later period. The genesis of bulge is mainly influenced by the lithology of the rock.4. The rocky reliefs all over the cave. Then, because of the tectonic uplift, the underground water constant dissolved the bottom rock and found a new outfall at the gap in the middle. Therefore the water flow was discharged here. During this period, because the new channel was not unobstructed, the discharge capacity was limited to result in flood congestion and accumulation of sediment. So, it caused the second half in the filling or semi-filling states to transform the old rocky relief frequently. At the same time, although the discharge capacity of the shaftlike sinkhole was limited, but the underground water also constantly discharge downward to fluctuate the groundwater table. Just because of the fluctuation of water, the shalftlike sinkhole was formed on the wall near the gap.5. Factors cause the processes acting upon the rock and remove their products. We have five categories based on the cause of formation, and respectively as rocky form due to water flow, rocky feature at the contact with fine-grained sediments, Rocky feature due to water tricking down the perimeter of shafts and passages, and the air currents due to moisture condensation give rise to the development of typical rocky features.6. We can find the two parts of the old Huanglong cave development in different stages. For the old Huanglong cave development process, we can speculate that in the pried of old Huanglong cave development process, it has experienced many times filling empty-to fill empty again process, until the sinkhole in the last second of the cave replaced by the new groundwater seepage path, completely out of groundwater, to form the cave today.