Mountain building in Taiwan: A thermokinematic model

The Taiwan mountain belt is classically viewed as a case example of a critical wedge growing essentially by frontal accretion and therefore submitted to distributed shortening. However, a number of observations call for a significant contribution of underplating to the growth of the orogenic wedge. We propose here a new thermokinematic model of the Taiwan mountain belt reconciling existing kinematic, thermometric and thermochronological constraints. In this model, shortening across the orogen is absorbed by slip on the most frontal faults of the foothills. Crustal thickening and exhumation are sustained by underplating beneath the easternmost portion of the wedge (Tananao Complex, TC), where the uplift rate is estimated to ~6.3 mm a^(−1), and beneath the westernmost internal region of the orogen (Hsueshan Range units, HR), where the uplift rate is estimated to ~4.2 mm a^(−1). Our model suggests that the TC units experienced a synchronous evolution along strike despite the southward propagation of the collision. It also indicates that they have reached a steady state in terms of cooling ages but not in terms of peak metamorphic temperatures. Exhumation of the HR units increases northward but has not yet reached an exhumational steady state. Presently, frontal accretion accounts for less than ~10% of the incoming flux of material into the orogen, although there is indication that it was contributing substantially more (~80%) before 4 Ma. The incoming flux of material accreted beneath the TC significantly increased 1.5 Ma ago. Our results also suggest that the flux of material accreted to the orogen corresponds to the top ~7 km of the upper crust of the underthrust Chinese margin. This indicates that a significant amount (~76%) of the underthrust material has been subducted into the mantle, probably because of the increase in density associated with metamorphism. We also show that the density distribution resulting from metamorphism within the orogenic wedge explains well the topography and the gravity field. By combining available geological data on the thermal and kinematic evolution of the wedge, our study sheds new light onto mountain building processes in Taiwan and allows for reappraising the initial structural architecture of the passive margin

Geomorphology of the southernmost Longitudinal Valley fault: Implications for evolution of the active suture of eastern Taiwan

In order to understand fully the deformational patterns of the Longitudinal Valley fault system, a major structure along the eastern suture of Taiwan, we mapped geomorphic features near the southern end of the Longitudinal Valley, where many well‐developed fluvial landforms record deformation along multiple strands of the fault. Our analysis shows that the Longitudinal Valley fault there comprises two major strands. The Luyeh strand, on the west, has predominantly reverse motion. The Peinan strand, on the east, has a significant left‐lateral component. Between the two strands, late Quaternary fluvial sediments and surfaces exhibit progressive deformation. The Luyeh strand dies out to the north, where it steps to the east and joins the Peinan strand to become the main strand of the reverse sinistral Longitudinal Valley fault. To the south, the Luyeh strand becomes an E‐W striking monocline. This suggests that the reverse motion on the Longitudinal Valley system decreases drastically at that point. The Longitudinal Valley fault system is therefore likely to terminate abruptly there and does not seem to connect to any existing structure further to the south. This abrupt structural change suggests that the development of the Longitudinal Valley suture occurs through discrete structural “jumps,” rather than by a continuous northward maturation

Fault diagnosis and yield enhancement in defect-tolerant VLSI/WSI parallel architectures.

This dissertation presents an integrated high-level computer-aided design (CAD) environment, the VAR (VHDL-based Array Reconfiguration) system, for the tasks of design, diagnosis, reconfiguration, simulation, and evaluation in a defect tolerant VLSI/WSI (Wafer Scale Integration) parallel architecture modeled by VHDL. Four issues in the VAR system are studied: (1) the development of a CAD framework for reconfigurable architectures, (2) the development of an array model, and its VHDL description and simulation, (3) the development of efficient fault diagnosis techniques, and (4) the development of a systematic method for evaluating architectures and yield. The first issue describes the modules in the CAD framework and their functionalities. The second issue addresses the hierarchical VHDL description and simulation of the array model, and the detailed designs of its components. The third issue proposes two fault diagnosis algorithms based on the parallel partition approach and the self-comparison approach respectively, and an optimal group diagnosis procedure. These fault diagnosis techniques all have the contribution of reducing testing time significantly under different application scenarios. The fourth issue depicts a complete set of figures of merits for quantitative architecture and yield evaluation. Although an easily diagnosable and reconfigurable two-dimensional defect tolerant array is used as an example to illustrate the methodology of VAR, the VAR environment can be equally applied to other parallel architectures. VAR allows the designers to study and evaluate fault diagnosis and reconfiguration algorithms by inserting faults, which are generated according to actual manufacturing yield data, into the array and then locating the faulty elements as well as simulating the reconfiguration process. Thus, VAR can assist the designers in evaluating different combinations of fault patterns, fault diagnosis and reconfiguration techniques, and reconfigurable architectures through the figures of merit with aim at architectural improvements. Extensive simulation and evaluation have been performed to demonstrate and support the effectiveness of VAR. The results from this research can drive the applications of large area VLSI or WSI closer to reality and result in producing low cost and high yield parallel architectures

Reactivation of Inherited Oblique Continental Margin Structures During the Development of the South-Central Taiwan Fold and Thrust Belt

The Taiwan orogen is forming due to the oblique collision between the Eurasian continental margin and the Luzon Arc. This configuration provides an opportunity to study the effect of inherited structures on the development of a fold and thrust belt (FTB). During the extensional tectonic history of the margin several NE trending basins filled with Eocene to Early Oligocene sediments developed on a pre-­‐Cenozoic basement, and further extension took place on the outer margin during the Middle to Late Miocene. The margintransition from the platform to the slope, and the large-­‐scale extensional features of the margin project obliquely onland across south-­‐central Taiwan. These basins are now involved in the Taiwan FTB.Peer Reviewe