delta: (in geology) Land that forms in the mouth of a river as silt that had been carried in the water settles out as currents slow when the river meets a larger body of water. Deltas allow the water to fan out in new channels, and sometimes to create wetlands for waterbirds and other animals.
downstream: Further on in the direction in which a stream is flowing or the path stream water takes as it flows towards a lake or sea.
fracture: (noun) A break. (verb) To break something and induce cracks or a splitting apart of something.
geology: The study of Earth’s physical structure and substance, its history and the processes that act on it. People who work in this field are known as geologists. Planetary geology is the science of studying the same things about other planets.
sea: An ocean (or region that is part of an ocean). Unlike lakes and streams, seawater — or ocean water — is salty.
sediment: Material (such as stones and sand) deposited by water, wind or glaciers.
tissue: Made of cells, it is any of the distinct types of materials that make up animals, plants or fungi. Cells within a tissue work as a unit to perform a particular function in living organisms. Different organs of the human body, for instance, often are made from many different types of tissues.