| Jurij Kasjan | |
| Birth Date: | 6 May 1961 |
| Birth Place: | Snjatin, Ukraine |
| Years Active: | 1978–present |
| Known For: | speleology, deep cave projects |
| Alma Mater: | Ivano-Frankivsk National Technical University of Oil and Gas |
| Children: | Anastasija, Sergej, Denis, Evgenij, Anatolij |
Jurij Mihajlovič Kasjan (also spelled Yuriy Mikhailovich Kasyan, Iurii Mihajlovič Kasian, pron. Yooreey Mikhaylovich Kasyan; Юрий Михайлович Касьян; born 6 May 1961 in Snjatin) is a Ukrainian speleologist, most known for his work in cave exploration, especially as the Call of the Abyss research project coordinator. He was heading the speleological expeditions to caves of the Arabika massif in Abkhazia and, with Aleksandr Klimčuk, to Aladaglar massif in Turkey. Some of the world's deepest caves were explored, including the first cave, deeper than 2,000 m, the Krubera-Voronja Cave.
Kasjan was born in Snjatin, a small town in Western Ukraine, in the Ivano-Frankivsk Oblast (Province), to the north of Moldova. His father Mihail Jurjevič Kasjan was chairman of the District Council of the Sports Society "Grain Ear", which promoted athletic development in the countryside, and his mother Nelja Dmitrievna was a statistician in the accounting department of the district party committee. After high school in Snjatin where he also pursued swimming and freestyle wrestling he graduated (1984) in geology at the Ivano-Frankivsk National Technical University of Oil and Gas in the province capital Ivano-Frankivsk. After graduation he moved to Poltava for a job in the regional branch of the All-Union Research and Design Institute for Explosive Geophysical Survey Methods. Kasjan continued as instructor at the Poltava regional center of education in tourism and local history and from there moved on to a career in industrial rope access.
In the autumn of 1978, at the beginning of geology study in Ivano-Frankivsk, there were 3 available extra-curricular courses: in tourism, rock climbing and speleology. From the latter two Kasjan chose speleology as the closest to geology and joined the Ivano-Frankivsk speleo club Протей [Proteus]. He stayed till 1984, since 1981 he was its chairman. In 1984 he founded the Poltava speleoclub "Poltava-speleo", which he led until 2003. In 2004 he joined the Kiev speleoclub; for several years he was the head of its speleo school, he is a longtime member of the club board.
In 1992 Kasjan was one of the founding members of the Ukrainian Speleological Association (UkrSA). As of April 2019 he is the vice-president of the UkrSA; he served as president in the years 1998–2001 and 2006–2007. Since 2003 he is an honorary member of the UkrSA, in 1996 and 2012 Kasjan was the recipient of the UkrSa Diploma for Outstanding Achievements.
He is the coordinator of the Training and Methodological Commission of the UkrSA, MIPKAR and “Call of the Abyss” projects, head of the UkrSA Cave Rescue Team.
From 1978 to 1998 Kasjan's caving activity was mostly devoted to caves of Western Ukraine and the Crimea, such as Gvozdetsky abyss, Liu-Khosar shaft, Shaft of the lost ones and discovery and mapping of over 1,5 km long Poltavskiy branch of the labyrinthine Mlinki cave. He initiated a program of marking and revising the caves of the Karabi plateau in the Crimea (1998).
From 1998 Kasjan participated in several international caving expeditions, to Arabika massif in Abkhazia (as a leader since 1999), to Skalarjevo brezno cave on Mt. Kanin in Slovenia and Aladaglar mountain range in Turkey as the leader of operations in the cave.
Cavers are known for their superstition, and Kasjan was never tempted to estimate expedition potential in advance:
Kasjan's most important achievements are connected to exploration of a cave system above the eastern coast of the Black Sea, in the Ortobalagan valley in Abkhazia.He was leading the following expeditions, nearly always organized by the Ukrainian Speleological Association:
His right hand in most of these projects was Russian cave diver from Simferopol, Gennadij Samohin; as of July 2019 cavers from 20 countries have participated in the list (sorted in descending order by the number of expeditions – given after the country name if exceeding 1): Ukraine (21), Russia (14), Israel (8), United States (4), Bulgaria (3), Lithuania (3), Poland (2), Spain (2), United Kingdom (2), Belarus, Belgium, Britain, France, Iran, Ireland, Italy, Lebanon, Moldova and Turkey.
Kasjan also made a major contribution to exploration of caves in the Aladaglar mountain ridge above the southern coast of Anatolia in Turkey, in the framework of the Call of the Abyss project. From 2002 to 2008 over 150 new caves were examined in the area, most notably Kuzgun cave, discovered in 2003, explored 400 m deep and in 2004 to its final (as of 2019) depth of 1400 m. In 2005, 2008 and 2013 three caves in the vicinity which could lead to greater depth were examined, 900 m deep side branch in Kuzgun was explored and engineering works at the cave bottom, which would stabilize loose collapse, were undertaken. In 2018 and 2019 Kasjan lead expeditions to new caves in the neighbouring area, also as part of the project.
Kasjan documented the underground explorations in which he participated in over 100 short films.His photographs, especially from the Krubera-Voronja cave were published in several national and international journals, books such as The Darkness Beckons,and other publications, including the official cave photo site of theUkrainian Speleological Association. He was a juror in international cave photography competitions.Since 2004 Kasjan is the editor of the Ukrainian speleo journal Свет [Light].