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.
For the water currents flow from the equator to the poles the presence of the unequal solar heating and the coriolis force exerted by the rotation of the earth is due to action to take place as the place in the surface of the earth is heated by the sun similar the water are driven by the winds to the east i.e the anticlockwise and to the south in the clockwise direction and this creates pattern of the cold and warm waters being drifted from the top to poles to the equatorial areas.
<u>This up-down movement created by the rotation is a significant life in the balance of the temperatures on the earth. </u>
<u>And hence creates a pattern of the movement of the warm and the cold current in the ocean that heats and respectively warm and cools the temperature of the coastal and with there respective periods.</u>
