Oldest Body of Seawater Found in Giant Crater

This is not in any form or fashion the "oldest body of seawater yet found" nor is it unusual to find ancient trapped seawater.

"Connate water" is water trapped in sediments at the time of their deposition. Whether or not connate water is preserved in large quantities depends on the local permeability structure of the sediments and the regional hydrology. However, it's very common for connate water to be preserved more or less indefinitely (particularly in shales).

In other words, there's a _lot_ of trapped seawater almost everywhere you look.

What's unique about this isn't that there's trapped seawater, and it's certainly not the oldest connate water discovered (nor do the authors of the actual article claim that it is).

It's unique because:

A) it's direct evidence that the Central Atlantic had a very high salinity even long after it opened. (The authors are using the term "north atlantic" for some strange reason, but this segment is more commonly referred to as the "central atlantic")

B) The connate water survived a metorite impact without being highly disturbed.

Geologists and oceanographers generally have to rely on indirect evidence from the analysis of solid materials in deep sediment cores when estimating temperature and salinity levels of the ancient oceans. But now a team from the US Geological Survey has identified a body of underground water that is actually a remnant of a past ocean water, a body of Early Cretaceous North Atlantic sea water. Deep drilling at the site of the Chesapeake Bay impact crater has yielded groundwater with an isotope and chemical composition signature that together with model analysis suggests that it was trapped in the sediments before the impact occurred around 35 million years ago. The water may have lain undisturbed for much longer: it has an average salinity of about 70 parts per thousand, twice that of modern sea water, and is probably 100–145 million years old.

http://www.nature.com/nature/journal/v503/n7475/full/nature1...

Is there significant creation of "new" water on the earth? I suppose water produced in combustion of hydrocarbons would qualify, but seems to me that's tiny compared to the existing amount of water, which is all roughly the same age (ancient) and is just continually cycling between vapor (evaporation) and liquid (clouds/rain) state.

This discovery is simply water that has been in isolation for a long time.