So there were no oceans before the flood? In the couple of thousand of years before the flood the water wasn't at its lowest point? :idunno:
Is this yet another miracle, in addition to the ones Baumgardner already admitted are required?
Come on, surely you are capable of better critical thinking than that. But maybe the concept is new to you and I doubt that you stopped to read anything so I'll help.
Step one, the world is created with both land and water. However, there is no rain, rather plants receive their moisture through mist. Think of that "primordial environment" that you sometimes hear described when evolutionists try to fit in how all the abundance of ferns and giant insects fit into things...
Genesis 2:4-6 KJV
(4) These are the generations of the heavens and of the earth when they were created, in the day that the LORD God made the earth and the heavens,
(5) And every plant of the field before it was in the earth, and every herb of the field before it grew: for the LORD God had not caused it to rain upon the earth, and there was not a man to till the ground.
(6) But there went up a mist from the earth, and watered the whole face of the ground.
Step two, skip forward about 1600 years. God sends a flood to destroy the earth. For some reason, rain falls for the first time, and it continues to rain. And although much water came from the rains, there is another source of water, namely the "fountains of the deep."
Genesis 7:10-12 KJV
(10) And it came to pass after seven days, that the waters of the flood were upon the earth.
(11) In the six hundredth year of Noah's life, in the second month, the seventeenth day of the month, the same day were all the fountains of the great deep broken up, and the windows of heaven were opened.
(12) And the rain was upon the earth forty days and forty nights.
In other words, water came from above, but it also came from below. Some came from the atmosphere (which formed a continual mist until this time) but the rest came from below the earth. Now what does this mean with basic math?
It means that if Current Oceans = former Massive Rains + former Massive Fountains + Former Oceans, that the former oceans are less than current oceans. I could write this mathematically as:
Former oceans < current oceans
Were there oceans before the flood? Undoubtedly so, but not in the scale that we have now. Let's translate this for you. They were smaller and/or shallower because they had less water mass in them. That also means that they weighed less.
When water from beneath the earth is moved to above the earth and covers everything by 15 cubits that is a lot of water. Were you to flatten the today's mountains and valleys with the water you find in today's oceans would cover the planet well over. Today's oceans are exceedingly deep.
I don't know if you have taken engineering courses, but there is a concept that certain materials can bear certain loads before they begin to deform and/or break. If you take large amounts of a heavy substance out from underneath something and instead place it on top, you may start to exceed its limits.
When the limits of a tectonic plate are reached, it does not "vaporize" the water on top of it. It may start to shift and slide or bend. If there are vacated spots beneath it (where water is no longer) it may start to collapse in that area. When one section starts to dip in, more water flows in, the weight and stress increases, and an ocean starts to deepen.
When an ocean starts to deepen, water flows in. If water flows in, it is flowing AWAY from someplace else. And as on part of the plate sags and starts to break, other portions get pushed up. Imagine smashing through a piece of wood with your hand, notice that you may break the board but the edges of the board go up.
Oceans and mountains would form together. For the most part, water drains into the oceans. In other places it may get stuck in lakes or larger watersheds. Should one of the large lakes later break loose it would quickly carve through that rock forming a canyon. But ultimately, water flows downhill and collects in the oceans.
So when you ask "there were no oceans before the flood?" Of course there were, but they couldn't have had the same depth and water volume as today because a lot of the world's water wasn't in the oceans. It was beneath the ground and in the atmosphere.
You asked about other miracles. Who is counting? From the perspective of a hamster, we perform multiple miracles just driving to work each day. We think of it as a single task and think nothing of the individual actions. Triggering this flood was a miracle, and it changed the earth environment permanently. Whether the tool of this triggering was a series of volcanoes, a comet strike, or the Divine Hammer of God the effect is the same and it still requires god-like intervention.