Zhaohui Wu

Bio: Zhaohui Wu is an academic researcher. The author has contributed to research in topics: Identification (biology) & Physics. The author has an hindex of 1, co-authored 1 publications receiving 45 citations.

The high-efficiency methods to identify lithology with well logging plates or a program

Abstract: As traditional manual method to identify lithology of cored wells is laborious and lack of efficiency, two efficient methods are used this time. One method is the identification with well logging plates while another is a program. The critical values of 5 kinds of well loggings are found to be relatively stable through many trials, and some major steps should be taken before using the logs. First is to find standard rock types and their logging values. Rock types are more reliable after the observation under microscopes. The second step is to find out the logging data ranges of each rock type. The third step is to quantitatively identify rock types with the optimal critical values. In this process, the multi-array logs (M2Rn) is found to be the most effective log to distinguish mudstone and oil reservoir. Low density (DEN) value is effective to distinguish the lightest matter or pores. The other two well logs, i.e. AC and CNL, can be used to distinguish whether there is limy content. Wave impedance (PD=DEN/AC) log can be a supplementwhen that kind of data is available, and finally all lithology is identified after that. The result that calculated from well logs with a program is similar to litholgy of drilling cores. Through many trials and errors, it is finally found and proved to be a successful approach to automatically and efficiently distinguish rock types in the software of Direct and Petrel. This method is more efficient and easier to operate with a program when there are hundreds of wells, and it is a progem made that work possible. There is more widespread use in deep carbonate buried hill with this method, simply by changing the lithology codes and critical values in the program.

Numerical simulation of large wave heights from Super Typhoon Nepartak (2016) in the eastern waters of Taiwan

Abstract: Super Typhoon Nepartak (2016) was used for this case study because it is the most intense typhoon that made landfall in Taiwan in the past decade. Winds extracted from the Climate Forecast System version 2 (CFSV2) and ERA5 datasets and merged with a parametric typhoon model using two hybrid techniques served as the meteorological conditions for driving a coupled wave-circulation model. The computed significant wave heights were compared with the observations recorded at three wave buoys in the eastern waters of Taiwan. Model performance in terms of significant wave height was also investigated by employing the CFSV2 winds under varying spatial and temporal resolutions. The results of the numerical experiments reveal that the simulated storm wave heights tended to decrease significantly due to the lower spatial resolution of the hourly winds from the CFSV2 dataset; however, the variations in the storm wave height simulations were less sensitive to the temporal resolution of the wind field. Introducing the combination of the CFSV2 and the parametric typhoon winds greatly improved the storm wave simulations, and similar phenomena can be found in the exploitation of the ERA5 dataset blended into the parametric wind field. The overall performance of the hybrid winds derived from ERA5 was better than that from the CFSV2, especially in the outer region of Super Typhoon Nepartak (2016).