Tracing the fingerprints of an ancient volcano

Tracing "fingerprints" of the ancient volcano

A volcanic eruption on the island of Thera thousands of years ago contributed to the collapse of Minoan culture and was a turning point in the history of Western civilization. However, the exact date of this event is unknown. Scientists want to establish it by looking for "fingerprints" eruptions in the rings of trees.

Southern Europe, the Middle Eastód and Egypt are the regions of the world with the most complete historical and archaeological data describing at least 10,000 years of. They are a record of wars, climate change, natural disasters. However, most of these events are not very precisely placed in time. The history of ancient civilizations also includes prolonged periods called "dark ages", for whomórych lacks any sources ofóde sources of historical information.

International Complexół scientistsóin, led by prof. Tomasz Ważny of the Nicolaus Copernicus University in Toruń, therefore intends to fill in some of these gaps by defining the dates of key events shaping the history of the cultures of the eastern basin of the Mediterranean Sea with theófrom the wild. In the Balkan-Egyptian Dendrochronology Project, which he is heading, the researchers want to use dendrochronology, i.e. analysis of the growth ofóin annual trees.

– Trees annually record the conditions of their surroundings in their wood structure. This record remains preserved in the wood in the form of so-called. jarów for hundreds or even thousands of years. The reliability of radiocarbon dating has been questioned in recent years, cores taken from glacialóin have a break, and only dendrochronology can provide unambiguous and indisputable dating expressed in calendar years. Sometimes it even allows to determine the season of the year in which theówhich was a concrete historical event,” stresses Prof. Important.

Scientists hope that the series of growthsóin the annual trees will enable them to date with the accuracy of the year pointóin the feedbacks of Western civilization, such as extreme climatic events or natural disasters. – The idea is to use dendrochronology to trace the ancient history of the eastern Mediterranean basinóCentury and to clarify a number of historical puzzles, whichóre still unexplained, wokółóof which there are numerous controversies,” explains the conversationóPAP reporter.

The most important intention of the scientistów is the precise dating of the volcanic eruption on the island of Thera, now known as Santorini. A volcanic eruption in the Aegean Sea not only blasted the island, but caused a gigantic tsunami thatóhe height of the volcano may have reached several tens of metersów. Cataclysm móhead contribute to the considerable destruction in Crete – óThe early center of Minoan culture and to the decline of that culture.

– The explosion was a turning point in the history of civilization. According to classical traditional dating, supported by archaeology, the volcano erupted around 1500-1550 r. p.n.e. However, radiocarbon dating pushes the date back a hundred years póThen. If the radiocarbon estimates were confirmed, the seemingly hitherto unassailable chronology of ancient Egypt would require a major overhaul, notes Prof. Important.

However, to conduct the study, scientists need wood and charcoal from the second millennium p.n.e. Some of the material already available for analysis comes from archaeological sites and tombsców. More scientists are yet to find in Turkey, Greece or the Balkans.

As described by Prof. Important, through wider rings the trees record favorable years for them; through narrower ones, unfavorable years. – The very narrow increments are a record of some phenomenon causing the so-called “narrowing”. The stress of a tree, that is, a definite negative reaction to unfavorable conditions. It could have been a climatic phenomenon or disaster, która severely interferedóThe tree’s growth. In extremely unfavorable years, trees may not grow at all for a year or even several years- mówi prof. Important. The longest incremental calendars date back to the 9th millennium p.n.e.

Trees can respond to a volcanic eruption in two waysób – depending on the distance to the epicenter of the explosion. PopióVolcanic lava fertilizes the soil at a distance of several hundred kilometersóin from the volcano. This causes the trees growing there to record a series of wider incrementsóin annual. On the other hand, trees closer to the epicenter may be damaged, strong ash fall can also significantly disrupt theócial process of photosynthesis. Then extremely narrow annual increments are produced. Already this is for the scientistóinówka, where – in który jars – look for "imprintóin the toeów" volcanic eruption, whichóry destroyed Thera.

However, it is not enough to find the volcanic signal itself in the wood. It is still necessary to identify który volcano móhead cause it. 4 thousand. years ago in the MediterraneanóIn the past, volcanic activity was much greater than it is now. – Identification "imprintóin the toeów" specific volcano is done on the basis of precise chemical analysis, elemental composition, isotopic composition of wood from individualólnych growthów. Identifying the eruption on Thera based on componentsów chemical components of volcanic origin embedded in the structure of a particular jar, will be a very difficult task, admits Prof. Important. Developed „incremental calendar” and disbursed timber remains with annual precision will allow verification of the history and dating of the prehistory of the eastern Middle Agesóbumblebee.

The five-year study, subsidized in the MAESTRO program by the National Science Center with more than PLN 3 million, will involve scientists from Greece, Germany, Turkey, Croatia, Bulgaria and the US University of Arizona – where the world’s largest growth research laboratory is locatedóin annual trees.