Matematičko određivanje promene brzine rotacije Zemlje na osnovu geoloških podataka

Mathematical determination of a change of the Earth's velocity on the basic of geological data

Abstract

In this paper the an attempt was made, using mathematical calculations based on geolug^ il (paleontological) data, to determine reduction of the Earth’s rotation velocity within its geological history, that was caused by tidal affects induced by gravitational pull of the Earth, the Moon and the Sun. Both the data on paleontological study of fossilized coral skeletons (thecae) and comparative analyses of modem coral skeletons represented die basis of these calculations. Thus, it was established, by determining the number of daily growth bands within annual growth rings of coral's thecae that a year lasted about 400 days in the Middle Devonian, about 385-390 days in the Upper Carboniferous and 380 days in the Lower Triassic. Under pressumption that the Earth’s rotation velocity reduced according to linear law within this time interval, it was calculated that for the last 385 million years this reduction was about 20 seconds per million years, the same as the length of a day increased. On this basis, duration of a day was established for a more distant geological past (up to 4000 million years ago) and a prognosis was given for duration of a day in the future.