UK archaeologists have discovered previously unknown traces of ancient structures that look like markings in the fields. The find was made possible by the heat, because of which the grass above the ruins, hidden by a thin layer of soil, grew differently than in the surrounding area. This is reported by Science Alert.
According to the publication, the marks indicate the location of the remains of the foundations of castles, fortresses, farm houses and mansions that date back to different periods of time, including the primitive era (for example, the Iron Age) or the first half of the 20th century. Some of them are known to scientists, but the prolonged summer drought, which had no analogues since the 70s of the last century, helped to discover new archaeological sites.
There are several mechanisms for the formation of such marks. First, plants can dry out completely due to the heat if they grow directly over stone walls or foundations that prevent the soil from accumulating enough moisture. In another case, water can accumulate in artificial ditches filled with soil, and then the grass above them, on the contrary, grows better than in other places. Differences become noticeable with relatively long periods of drought, so under normal conditions the ruins remain hidden for many years or decades.
The 1976 drought helped British explorers discover many new archaeological sites. Scientists believe 2018 could be just as productive, especially given the advances in unmanned aerial vehicle technology that allows markings to be seen from above.