Invitation for a PhD Defense... My PhD Defense
It is available only in Bulgarian however the language of photography gives a glimpse on the field work. Although it took about a month, it marked my dissertation. And it wouldn't be possible without the support of my friends, some mentors and organisations - some help that I greatly appreciate.
PS The abstract (in Bulgarian) can be found HERE.
Using GPR for Cavity Detection in the Vicinity of Duhlata Cave
Atanas Rusev, Tanya Slavova, Rangel Gyurov
Duhlata cave is the longest (18 km in length) cave in Bulgaria, located in Bosnek karst area. Its 8 underground rivers flow is several times less than the surface springs flow, and probably more underground rivers and cave galleries are still undiscovered. For many years in Pepeliankata cave, located nearby, have been made attempts to discover its lower levels and to penetrate in new cave galleries and underground rivers that also stems from the same springs. Ground Penetrating Radar is used, for the first time in Bulgaria, to locate new cave entrances and galleries close to the surface, nearby Peleiankata Cave. Several possible new cave entrances and a cave room were located after analyzing results from the GPR’s radagrams.
Balkan Speleological Conference, Sofia, 2014
Mapping the Zhivata Voda Cave (The Living Water), Bosnek Karst Region
A Tale About the Living Water and Gravimetry
Analysis of the Applied Gravimetric Techniques for Detection of Underground Cavities
Tanya Slavova
Gravimetric methods are based on the natural gravity field of Earth. Measuring it with high accuracy and resolution makes it possible to resolve a variety of issues - from fundamental problems to tasks of small scale but large significance. Technological progress during the last decades have also expanded the applications, and the principle, which gravimetric methods are based on, confirmed their applicability for certain targets.
Cavities are features with typically high density contrast to the surrounding rock. On one hand, their detection is a classical gravimetric task. On the other hand, exploring their exact location, shape and size is an important issue for engineering, various sciences and ecology.
Spatial Cave Mapping in Bulgaria
Tanya Slavova, Atanas Rusev, Asparuh Kamburov
Caves are natural underground spaces formed and shaped over millions of years. Usually part of bigger caverns, they give a first-hand view of water, biology, oil and other subsurface distributions as well as a glimpse of the past when they perhaps offered a shelter or sanctuary. Therefore, when exploring a cave, it is useful to not only collect geometric information such as gallery dimensions and directions but also to take photographs and notes of any specific features of interest. Since safe storage, easy management and proper representation of spatial data can be difficult using traditional methods, these are all key requirements in the search for modern solution.
Optimizing the Period of Remeasuring the National 1st Order Levelling Network in Order to Determine Contemporary Vertical Crustal Movements
The article is available only in English HERE.
Modern Methods and Devices for Mapping Underground Galleries and Natural Caves
Eng. Tanya Slavova
Abstract: It is made a review of the classical techniques and devices used for mapping underground galleries and natural caves. A new method is supposed and realized by the means of modern technologies in the Pepelyankata cave nearby the village of Bosnek, Pernik Province.
A GPS receiver is used to determine the coordinates of an initial point, which accuracy is later improved by postprocessing. Another device - a combination between a laser rangefinder, a compass and an inclinometer, is used to measure the polygon and certain points inside the cave. All of the measurements are transferred wirelessly to a PDA device and represented by a suitable field software with GIS capabilities. Some other data, including photos made by the PDA’s integrated camera, is collected as an additional attribute information about the points.
Back in the office, it is built-up a TIN model to define the main direction of the cave, its surface, volume and other morphological features. It is also compared with the results of a previous mapping of the cave which is done by other means, to figure out the advantages and disadvantages of the supposed method. The model is also drawn on an orthophoto map of the region in order to find relations between the geological features of the ground and cave’s morphology.