Seven Days in Creation

In the beginning God created the heavens and the earth. And the earth was without form, and void; and darkness was upon the face of the deep. There is a major time span between the creation of earth and the creation of man. This is commonly referred to as the Gap Theory. Please follow carefully. Based on scientific study, the Earth has been here for millions of YEARS! The time between the creation of the earth and when God started to prepare earth for His ultimate creation "man" was an astronomical amount of time. If everything God creates is good, what happened to the earth to make it dark, without life and without form?