晚新生代台灣西部前陸盆地之震測地層學、前凸起隆升與前陸演化
Other Title
Seismic stratigraphy, Forebulge uplift and Foreland Evolution of Late Cenozoic West Taiwan Foreland Basin
Date Issued
2007
Author(s)
俞何興
Abstract
This study try to understand the depositional sequences of the West Taiwan Foreland Basin which is a transition between passive margin setting and uplift orogen setting and of evolution of foreland sequences, using seismic profiles, bathymetry data and previous researches.
Within the foreland basin system, the Changyun Sand Ridge located at the middle of Taiwan Strait could be regard as a modern forebulge depozone, and the Wuchiu Depression might be a corresponding backbulge depozone; Strike-slip duplex at the north of Penghu Island might be regard as a second-order escape extrusion under flexure tectonics influencing on passive margin; The thickness of foreland sequence is affected by flexural faulting system in front of orogeny load at early stage, and migration of depositional center going on with propagation of orogen; Instead of landward migration, the behavior of forebulge should be uplifted vertically and onset between 6.5 - 5.6 Ma. The tectonic effect by foreland basin system might not be significant since Kueichulin Formation corresponded to eustatic sea level change and the Kueichulin Formation might means an unaffected tecton - sediemntary unit. The locality might be the hinge of forebulge flex.
The Luzon Arc has collided collide with Euro - Asia continent margin since late Miocene. The slope sediments and Allochthon bended the lithosphere and formed the forebulge in the middle of Taiwan Strait. The eroded part of forebulge was transported eastward and deposited Kueichulin Formarion which was controlled by eustatic sea level than tectonics on the hinge of forebulge and Chinshui Formation which is recognised as a initial deepening of foreland basin and not correspond to eustatic sea level change. The thickness is controlled by flexure faulting system. After Pleistocene the uplift of Taiwan orogen was fast and Hsuehshan Range became the prominent sediment source, the Cholan Formation was formed; At later stage and deposition center shift after Central Range appeared, forming the Tuokoshan Formation. Lasting, active tectonics accompanied with sediment supply from Taiwan orogen, results in modern West Taiwan Foreland Basin System.
Subjects
前陸盆地系統
震測地層
foreland basin system
seismic stratigraphy
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-96-R94241306-1.pdf
Size
23.53 KB
Format
Adobe PDF
Checksum
(MD5):bc84a0f35796ed9b2d7d903014b61ff7