Drainage Development in the Dunhuang Basin, NE Tibet, Controlled by Multi-Segment Fault Growth

The Dongbatu Shan (DBTS, also known as the Nanjie Shan), which interrupts the northern Tibetan foreland in the Dunhuang basin, is an active anticline. It has accommodated the northwestern growth of the eastern Altyn Tagh fault system (ATF). Although several thrust faults have been identified around the DBTS, their evolution history and influence on regional landscape have received little attention during the late-Quaternary. In this study, several geomorphic methods are used to investigate the interaction between drainage development and tectonic movement around DBTS. Based on high-resolution satellite images, field investigation, and cosmogenic nuclide 10Be dating method, the fluvial landform sequences around DBTS were constructed. Using quantitative geomorphology methods including landscape relief profile, asymmetry factor (AF), and transverse topographic symmetry factor (T), we hypothesize that drainage deflection is controlled by multi-segment fault growth. Combining the results of the above-mentioned methods, we propose that Yulin He, flowing across the DBTS, had gone through several abandonments since the late mid-Pleistocene due to the lateral propagation of DBTS. Affected by the discharge of channel and multi-segment fault growth, our research confirms that the direction of river abandonment may have decoupled with the mountain range propagation trend. Based on the chronology dating, the DBTS has gone through two severe uplifts since ∼208 ka and the shortening rate across the central DBTS is constrained to be ∼1.47 mm/yr since ∼83 ka. Given the fact that thrust faults are widely developed around DBTS, we propose that the flower-like structure formed by the northward growth of the eastern ATF could better explain the development of the secondary subparallel faults.

TO THE QUESTION ABOUT TAMPONATION OF THE ABDOMINAL CAVITY

Professor Mikulicz, in 1886, proposed his own method of tamponation of the abdominal cavity. Among the properties of such a tampon, the main role is undoubtedly played by its draining action, and therefore tamponation should be considered as an improved method of drainage. On this basis, I will briefly trace the issue of drainage development and then move on to tamponation.

Land Drainage Development Processes and Changes in the Context of Runoff Change in Northern Lithuania

The impact of the drainage of excessively wet land on river runoff has so far been assessed differently and very carefully because of its complexity and diversity. The article analyses changes of drained land areas and runoff in the river basins of Mūša, Lėvuo Tatula and Nemunėlis. Wet land areas in the Mūša, Lėvuo and Nemunėlis rivers basins account for more than 70% from the total basins area and in the Tatula about 90%. Increase of drained land areas in the studied river basins has no significant influence on the change of river runoff. Studies have shown that the change in drained land areas did not affect the change in runoff height. Drainage does not have a significant effect on changes in the annual runoff distribution of the studied rivers.