This paper focuses on caves in Pleistocene carbonate conglomerates in Slovenia and for the first time defines them as eogenetic. The conglomerates show no deep burial that would resemble the ...mezogenetic stage of diagenesis and are still in the phase of early diagenesis (i.e. eogenetic stage). Based on speleological analysis the eogenetic caves were grouped into four types; (1) linear stream caves, (2) shelter caves, (3) breakdown caves, and (4) vadose shafts. All four types of caves, described in this paper, can appear individually, however, complex cave systems are often a combination of passages of different types.
Ivan Gams – karstologist KRANJC, A
Acta geographica Slovenica : Geografski zbornik,
01/2013, Letnik:
53, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Academician Ivan Gams is Slovenia's best known researcher of karst and the most prolific author of works on karst. During his first job at the Institute of Geography of the Slovenian Academy of ...Sciences and Arts, he started researching the karst surface and underground. He published several in-depth publications on karst caves, the most well-known being the studies of the shaft Triglavsko brezno in the 1960's. Right from the beginning, he focused on issues to which he then dedicated more or less his whole life − and which were also widely recognized by professional public both at home and abroad −, namely corrosion intensity determined by the hardness of water and the discharges of karst rivers and springs, and the method of limestone tablets. Within the geomorphology of karst, Gams was mostly dealing with the karst polje, especially its definition and evolution.
Konya region is located near Tuzgölü (salt lake) in the center of Turkey. The surface of the study area which is between Çumra-Karapınar and Aksaray-Sultanhanı-Obruk plains in the Konya region is ...2,100 km
2
. Obruk landforms are concentrated in a 100 km
2
section of the study area which contains approximately 50 obruks. The climate is typically continental and annual average precipitation varies between 314.2 mm/year in Sultanhanı, 298.4 mm/year in Karapınar, and 333 mm/year in Beşağıl. Evaporation value is 1,444 mm/year. In the study area, agricultural activities are carried out on 5,115 ha of land, which is irrigated from the 109 wells drilled and operated by several soil-water cooperatives. The static water levels in the wells vary between 75–91 m. Even though Karapınar and Sultanhanı plains are closed basins, there is groundwater connection between them. Since the groundwater flow in this area is canalized between some lithological and tectonic barriers, the underground formations are eroded by groundwater flow moving between the limestone. Over time, dissolution occurs within the limestone formations and they eventually collapse. Generally speaking, circular obruks are formed in horizontal layers and oval ones are observed in layers with inclination. Some obruks reach the groundwater table. The main composition in the study area is, from the oldest to the youngest, Paleozoic schist–fillit–quartzite–crystallized limestone and Mesozoic ophiolites, Cenozoic limestone with pebble, marl, clay, calcite, silica, dolomites and tufa, marl layers with gypsum and salt, lacustrine limestone with tufa layers and andesite near the volcanites, sediments of clay, sand, pebble, and silt of Plioquaternary and basalt flows. Samples collected from all of the sampling stations were analyzed and hydrochemical graphs were prepared. According to hydrochemical evaluations, pH is between 7.1 and 8.2, EC is between 840 and 1,965 μmho/cm, and hardness varies between 40 and 81 FS°, and the water is classified as C
3
S
1
category according to US Salinity Laboratory interpretations. With respect to irrigation water criteria, the water is of good quality, but not good as drinking water. In the study, the effects of dissolved CO
2
in groundwater on karstification were also investigated. Water from wells drilled at Yarımca, Açıkkuyu, and Badırık plains contains large amounts of CO
2
. As is commonly known, those waters which contain CO
2
more than 50 mg/l are considered to be corrosive and can cause dissolution of limestone. Through the preparation of topographical elevation maps of the groundwater, water level maps were drawn and the flow direction of groundwater, recharge area of groundwater, groundwater hydraulic balance and level fluctuations of the groundwater, as well as the locations of possible exploitation sites were determined.
Dedicated work of Dragutin Gorjanović-Kramberger is hereby presented on the occasion of celebration of one hundred and fifty years of his birth. His dedication in the development of first mapping ...sheets for geology map of "Croatia and Slavonia" and works in other areas of "practical geology" have led to the development of "Geological council" and independence of Croatian geology from foreign influence.
The buried Chicxulub impact structure is marked by a dramatic ring of sinkholes (called cenotes if containing water), and adjacent less prominent partial rings, which have been shown to coincide with ...maxima in horizontal gravity gradients and a topographic depression. These observations, along with the discreteness and spacing of the features, suggest a formation mechanism involving faulting in the outer slump zone of the crater, which would thus have a diameter of approximately 180 km. An opposing view, based primarily on the interpretation of gravity data, is that (he crater is much larger than the cenote ring implies. Given the association of the known cenote ring with faults, we here examine northern Yucatan for similar rings in gravity, surface features and elevation, which we might expect to be associated with outer concentric faults in the case of a larger, possibly multiring, structure. No such outer rings have been found, although definite patterns are seen in the distribution of karst features outside the crater rim. We explain these patterns as resulting mainly from deformation related to the block fault zone that parallels tbe shelf edge of eastern Yucatan.
Nickpoint recession in the Buchan karst, southeastern Australia, has resulted in the formation of an underground meander cut‐off system in the Murrindal River valley. Three nickpoints have been ...stranded in the surface channel abandoned by the subterranean piracy, and these can be correlated with river terraces and epiphreatic cave passages in the nearby Buchan River valley. The presence of palaeomagnetically reversed sediments in the youngest cave passage in the Buchan valley implies that the topographically lowest nickpoint in the Murrindal valley is more than 730 ka old, and the other nickpoints are probably several million years old. The nickpoints are occasionally active during floods, but the diversion of most surface flow underground has slowed down their retreat to the extent that they have been effectively stationary for several million years.
Underground nickpoint migration has been by both incision within major phreatic conduits and their abandonment for lower‐level passages. The nickpoints are all present in the upstream part of the cave system, but have not migrated past the sink in the river channel, despite the long period of time available for this to happen. The sink is characterized by collapsed limestone blocks; these filter out the coarse bedload from the river channel. As a result, erosion within the cave passages is dominantly solutional and therefore slower than in the surface channel, where it is mostly mechanical. In addition, to transmit a drop in base level the cave system requires the removal of a larger volume of rock than for the surface migration of a nickpoint, because any roof collapse material in the subsurface system must be removed. These factors have slowed the migration of the base‐level changes through the subsurface system, and may be a general feature in caves that have diffuse sinks as their main inputs.
Razvoj znanstvenih disciplina koje se s raznih aspekata bave Zemljom, njenim postankom, njenom poviješću, sastavom i procesima kroz koje je prolazila ili upravo prolazi, izuzetno je napredovao ...posljednjih nekoliko desetljeća. Količina znanja se enormno povećala, a s njim i terminologija kojom se to znanje izražava. Točno poznavanje značaja nekog izraza posebno je važno za osobe koje se i same bave stručnim i znanstvenim radom, koji prate radove objavljene u stručnim časopisima i koje i same u njima objavljuju svoje radove.
Ovdje su prikazani prikupljeni pojmovi iz područja fenomena krša koji se odnose na njegove površinske i podzemne morfolološke oblike.
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