Ha Long Bay, Vietnam

By Cahaya Asia -

Ha Long Bay, within the Gulf of Tonkin, includes some one,600 islands and islets, forming a spectacular seascape of limestone pillars. attributable to their precipitous nature, most of the islands are uninhabited and unaffected by somebody's presence. The site's outstanding scenic beauty is complemented by its nice biological interest.

Ha Long Bay, situated within the Gulf of Tonkin, includes some 1600 islands and islets forming a spectacular seascape of limestone pillars. attributable to their precipitous nature, most of the islands are uninhabited and comparatively unaffected by human influence.

The geomorphology of Ha Long Bay is thought as a drowned karst landscape attributable to the exceptional combination of its limestone karst options that are subject to repeated regression and transgression of the ocean over geological time. The limestones of Ha Long Bay are eroded into a mature landscape of fengcong (clusters of conical peaks) and fenglin (isolated tower options) karst features, changed by ocean invasion at a later stage.

The smaller islands are fenglin towers of 50m to 100m high with height. several have vertical walls on all or most sides and these still evolve by rock falls and enormous slab failures.

Marine invasion of Ha Long Bay has added an additional component to the traditional method of lateral undercutting of the limestone towers and islands. the foremost conspicuous feature being the most notch cut into the complete rocky coastline. Notches are a feature of limestone cliffs worldwide, however those of Ha Long Bay are exceptionally well developed and, at several sites, extend into arches and caves. This method of undercutting and subsequent erosion maintains the steep faces of the fenglin karst towers and thereby perpetuates the spectacular nature of the landscape.

A distinctive feature of Ha Long Bay is that the abundance of lakes at intervals the larger limestone islands.
Extensive limestone caves represent another vital feature of Ha Long Bay, with 3 main sorts able to be identified: recent phreatic caves shaped below the water table of the time; recent karstic foot caves shaped by lateral undercutting of cliffs at base level; and marine notch caves shaped bewildered level where rock structures are powerfully eroded and eventually reduced to a wave cut platform.

In summary, Ha Long Bay possesses an incredible diversity of caves and alternative landforms that derive from the bizarre geomorphological method of marine invaded tower karst. These areas give a novel and in depth reservoir of information for the longer term understanding of geoclimatic history and therefore the nature of karst processes in a very complicated setting.