Padre Island
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Padre Island, the world's longest barrier island, is a Gulf coast island with white sandy beaches at the south end, along the coast of southern Texas. It is named after Padre Jose Nicolas Balli (177?-1829), who served as collector of finances for all the churches in the Rio Grande Valley and founded the first Mission in present Cameron County.
Padre Island is some 130 miles (210 kilometers) long, stretching from the city of Corpus Christi, in the north, to the town of Port Isabel in the south. The island is oriented generally north-south, with the Gulf of Mexico on the east, and Laguna Madre on the west. The island's northern end connects to Mustang Island by roadway. The southern end of the island is separated from Brazos Island by the Brazos Santiago Pass.
The island as a whole is sparsely populated; that said, the towns of South Padre Island and Port Isabel are located at its southern end. The central part of the island is preserved in a natural wild state as Padre Island National Seashore. Since 1964, the island has been divided by the artificial Port Mansfield Channel, and as a result, "North Padre Island" and "South Padre Island" are often used to refer to the separate portions of the island. Padre Island is located in Cameron, Kenedy, Kleberg, Nueces, and Willacy counties.
Padre Island is young in geological terms, having formed only in the last several thousand years.
[edit] Geology
Geologically speaking, Padre Island is a young island. It is one of 300 islands stretching from Maine to Mexico. These natural barrier islands act to protect the mainland from the direct onslaught of storms.
Padre Island began forming as a submerged sand bar some 4500 years ago, as shown by radiocarbon dating of shells. Geologic speculation indicates the emerged island itself may be 1000 to 1500 years younger. Barrier island origins have been debated for many years by geologists, but it is agreed they are formed and modified by such factors as sediment type and supply, sea-level directional changes, current and wave strength and direction, and tide magnitude.
It is theorized that Padre Island formed from offshore shoals with later growth aided by spit accretion. (A spit is a long, narrow tongue of sand extending from a mainland shoreline and formed by the shoreline drifting of sediments.) After a history of shifting, abandonment and reestablishment by storm breaches, many tidal inlets were slowly closed and short islands were joined to form today's longer islands.
Padre Island graphically illustrates the life and sequences of a barrier shoreline: accretionary or building phase, equilibrium or stability phase and erosion or destructional state. The northern half of Padre Island's shoreline is in equilibrium; the southern half (and much of the remaining Texas coastline) is in an erosional stage. Wind, wave and current action continue to rework and shape the island. South Padre Island has been in a destructive phase for a long time, probably having retreated landward (along with the lagoon and mainland shoreline). All of Padre Island will probably retreat landward through long-term erosion due to three causes: interruption and decrease in sediment supply, relative sea level rise, and tropical storm activity. Today, hurricane washovers and wind-carried sand deposited in the Laguna Madre build Padre Island's landward side at the expense of the Laguna Madre.
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