I am also aware that speleothems are rarely pure calcium carbonate, but often contain large amounts of impurities such as soil or clay particles or surface organic material. |
Speleothems usually display a layered or banded structure in cross section, not unlike growth rings in a tree. |
More interesting for purposes here is that prolonged droughts can mask hurricanes and other major rainfall events in speleothems. |
In eight groups of rockfalls more than 75,000 years old, broken speleothems are the only record of the prehistoric seismicity. |
In caves, a variety of features collectively called speleothems are formed by deposition of calcium carbonate and other dissolved minerals. |
The most common type of speleothems studied for palaeoclimate are cylindrical stalagmites. |