delta

Perseverance was dispatched to the Jezero Crater because it showed qualities that may have meant it was once conducive to life, including signs it was once a delta when Mars could sustain liquid surface water.

Ms. Low rehashes that old story, but concedes the delta is at least partially a product of the fact that “many women want to spend time at home with their children.”

The country is essentially a large delta crossed by three major rivers, the Rhine, Schelde, and Maas, that flow into the unpredictable North Sea.

Over time, sediment carried by rivers built deltas at the head of the Gulf, cutting off tidal access to inland areas.

Many of its largest cities -- including Shanghai, Shenzhen and Hong Kong -- sit in delta regions made of soft, water-saturated sediment that naturally sinks over time.