Extensional Sedimentary Basins



So I have just had a lecture at my university about extensional sedimentary basins, and I just don’t understand it.

How do they stratigraphically develop, and what structural and geodynamic processes control them, and how do they do it?

Any links to any good articles/papers etc. that you know will also be greatly appreciated, so I can have a read myself too!

Thank you Reddit!

In: Earth Science

Extensional sedimentary basins form at divergent boundaries. The two plates are moving apart, causing a rift to form. Examples of this include the Mid-Atlantic Oceanic Ridge (oceanic rifting) and the East African Rift Valley (continental rifting).

As the rifting occurs, the crust thins because it is being stretched out. Think of it as pulling apart two ends of play doh. Eventually, you will get a basin in the middle.

Erosion transfers sediment from topographic high points to topographic lows, so eventually, the basin that forms will accumulate the outwashed sands, silts, clays. Over time, sedimentation will cause these sediments to chemically bind forming sedimentary rocks.