An inverted river delta is special category of river delta in which the narrow end of the delta emerges on the seafront and the wide end is located further inland, so that with respect to the seafront, the locations of both ends of the delta are inverted. A delta is a Landform where the mouth of a River flows into an Ocean, Sea, Estuary, Lake or another river

Explanation

A picture of California's Sacramento-San Joaquin River Delta, with Suisun Bay at left-center and the Carquinez Strait at far left

In a typical river delta, the narrow end of the delta is located at the point where a river enters a delta, with a wide fan-shaped sedimentation region extending outward into the body of water into which the river empties. The Sacramento-San Joaquin River Delta is an expansive inland River delta and Estuary in northern California in the United States. Suisun Bay (pronounced "soo-soon" is a shallow Tidal estuary located at in central California, USA. The Carquinez Strait is a narrow tidal Strait in northern California. In some rare cases, the delta is located at the waterway's exit from a large, flat valley, yet still inside the valley. The sediment is dropped within the valley and the clear water then exits into a bay or the ocean, so the apex of the delta is at this exit, a configuration said to be inverted from that usually seen. Inverted deltas typically do not last long in geological terms, since they tend to fill up with sediments rather quickly and eventually become normal deltas.

Examples

The Sacramento-San Joaquin River Delta

A classic example of an inverted river delta is the Sacramento-San Joaquin River Delta, which lies at the confluence of the Sacramento and San Joaquin rivers in California. The Sacramento-San Joaquin River Delta is an expansive inland River delta and Estuary in northern California in the United States. The Sacramento River is the longest River entirely within the U The San Joaquin River ( 330 miles (530 km long is the second-longest River in California, United States. California ( is a US state on the West Coast of the United States, along the Pacific Ocean. The water from the rivers that drain the entire, large California Central Valley exit through the Carquinez Strait, a narrow gap in the Coast Range. The Central Valley is a large flat valley that dominates the central portion of the U The Carquinez Strait is a narrow tidal Strait in northern California. The Coast Ranges of California constitute one of the eleven traditional geomorphic provinces of California. An inverted river delta exists behind this strait.

The Tagus River

Another example is the delta of the Tagus river in Portugal, although due to sedimentation this delta is now only very partially inverted, with the valley now mostly filled with sediment. The Tagus ( Latin Tagus, Spanish Tajo, Portuguese Tejo, pron. It is still about 15km wide and 25km long, compared with the 2km wide exit into the sea, and forms a large lagoon with large and very shallow sand banks which go uncovered during low tides. The delta used to be even bigger thousands of years ago.