Holocene tectonic uplift on the Hua-tung coast, eastern Taiwan

We used radiometric dates from 19 sites to determine the Holocene uplift rates of the 140-km-long Hua-tung coast in eastern Taiwan. These rates ensure that the formation of major marine terraces on the coast, several tens of meters in height, is related to the deglacial relative sea-level cycle, with which the uplift rates were further constrained by the elevations of the marine-terrace elements. Uplift rates are less than 4 mm/yr in the northernmost 30 km-long coast, and are 4–7 mm/yr in the adjacent 30-km-long coast. The rest of the coast is generally uplifted 7–9 mm/yr, with local troughs ( 700 m) and high (>40 m) mudstone platforms are observed to slope below the sea level. These changes in uplift rate or style are all accommodated on the surface by warping. Most of them are irrelevant to the known bedrock structures, suggesting a change in uplift style, and perhaps also mechanics, of the coast during the Holocene.