I would venture that Chapters Eight and Nine are describing the Great Tribulation. We noticed in the preceding chapter the people who had been saved out of the Great Tribulation.
The first angel sounded his trumpet, and there came hail and fire mixed with blood, and it was hurled down on the earth. A third of the earth was burned up, a third of the trees were burned up, and all the green grass was burned up. (Revelation 8:7)
And out of the smoke locusts came down on the earth and were given power like that of scorpions of the earth. They were told not to harm the grass of the earth or any plant or tree, but only those people who did not have the seal of God on their foreheads. (Revelation 9:3)
Such is the tribulation that is coming. Perhaps it is the Great Tribulation.
The Day of Wrath is described in a future chapter, I believe. Wrath and tribulation are not at all the same condition. Wrath is not redemptive. Tribulation may be thought of as chastening, in many instances, and as such can be redemptive.
The chaos in the world of today makes me believe that the current catastrophic events are leading up to the Great Tribulation. However, first must come the worldwide witness of the coming of the Kingdom of God to the earth.
Today it appears that the earth is vomiting out its inhabitants because of the prevalence of sin, particularly that of abortion on demand. I believe the closing days of the Church Age are going to be filled with every sort of trouble and confusion. We do well if we draw close to the Lord Jesus and seek to live by His Life.