Answer:
potassium-argon dating
Explanation:
Potassium-argon (K-Ar) dating technique is the most appropriate dating method for establishing the age of a volcanic ash. It is most applicable for dating minerals and rocks more than 100,000 years old. It is based on measuring the product of the radioactive decay of an isotope of potassium (k) into argon (Ar). Since potassium is a common element found in many volcanic ash layer, the time since re-crystallization is calculated by measuring the ratio of the amount of argon 40 (Ar-40) accumulated to the amount of potassium 40 (K-40) remaining in these volcanic ashes.
Answer:
sudden and quicker
Explanation:
The climate on Earth has always been changing, and there are numerous factors that have had their influence on it. Some of the factors are the plate movement and the astronomical causes. Both of these factors though result in gradual changes of the climate, which can take thousands or even millions of years in order to have a significant change. The volcanic eruptions are another story. They are also one of the factors that influence the climate, but unlike the other two factors that are mentioned, the volcanic eruptions cause sharp and sudden climate changes. If the volcanic eruption is massive, or there are several volcanoes around the world erupting at the same time, they are able to change the global climate in just few days. Usually it is the enormous amounts of ashes and other particles released in the atmosphere that are blocking the sunlight and cause sudden cooling of the planet.
Industrialisation. Or that's what I think