2019 Kirk Bryan Award

Presented to Kristen L. Cook with Jens M. Turowski and Niels Hovius

Kristen L. Cook

Kristen L. Cook

Awarded for: 2014, River gorge eradication by downstream sweep erosion. Nature Geosciences 7: 682-686. DOI: 10.1038/NGEO2224.

 
 

Citation by Alison Duvall, University of Washington

It is my honor to write the citation for this year’s Kirk Bryan award-winning paper by Kristen Cook and co-authors. Their study focuses on the Daan River and the gorge that it has carved into an anticline in the tectonically active western foothills of Taiwan. The anticline grows from successive uplift events along the Chelungpu fault, most recently during the Chi-Chi earthquake in 1999. The authors capitalized on a brilliant natural experiment investigating the effects of earthquakes and fault motion on rivers, completing a tectonic geomorphology study with a twist.

Instead of focusing on the coseismic formation of a gorge, as others have done previously, the authors investigate the gorge disappearance in the years following the initial uplift and incision. In doing so, they get to the heart of the fluvial processes acting on the channel over time– the processes that ultimately dictate the full life cycle of bedrock gorges. To explore this problem, the authors did the meticulous and onerous work of mapping channel width and documenting lateral erosion processes in the gorge and upstream. Their results reveal a mechanism of gorge eradication, which they coin “downstream sweep erosion”, that rapidly transforms a steep sided canyon into a beveled floodplain. They further argue that this process should erase the uplifted Dongshi anticline topography in as little as 50 years! The paper makes for an enjoyable read not just because the topic is fascinating, but also because the writing is clear and compelling, the illustrations masterful, and for the surprisingly thorough nature of such a short piece. In its rather brief life, Cook et al. (2014) has generated wide interest and citations. I anticipate the paper will continue to spark discussion and inspire future research for generations to come.

 

Response

We’d like to thank Alison Duvall for her very kind words and for both thinking of our paper and putting in the work to nominate it. We’d also like to thank those that wrote letters in support of the nomination and the QG&G division for selecting our paper for this award. It’s a great honor and one that came as a huge surprise! Since I’m representing the team, I’d like to highlight my co-authors: Jens Turowksi and Niels Hovius. Collecting nice data is one thing, but figuring out what you can learn from it is not always so straightforward, and this paper arose from extended discussions among Jens, Niels and I. It was a great collaborative effort, which made it quite a fun paper to write. I also want to thank a number of people who are not co-authors. First, and most important, is John Suppe. John was my postdoc supervisor during my years at National Taiwan University, when most of the data collection for this paper was done. John was an extremely generous supervisor, providing me with support and mentoring while giving me the freedom to pursue my own projects. I couldn’t have done the Daan River work without his support, and I am very grateful for it. This paper is one of the results of a long-term monitoring campaign in the Daan River, and over the years I have had a huge amount of field assistance from a wide range of people. I can’t name everyone, but Mong-Han Huang, Po-Nong Lee, Chia-Yu Chen, and Wan-Yun Ho each spent a considerable amount of time out on the river with me, patiently putting up with survey after survey after survey.

In general, I hope that this paper highlights some of the benefits of long-term monitoring campaigns. When I started working on the Daan River, I didn’t really know what would come out of it, but I figured that something interesting would probably happen, so I’d better stick around to watch it. I was lucky to be able to continue watching for almost ten years, and to record a whole range of interesting and sometimes unexpected things, such as the role of bedload in driving erosion and the impact of channel width differences on bedload flux variability. This was possible because of the very flexible funding that John and Niels received from Taiwan’s Ministry of Science and Technology and from Germany’s Helmholtz Association, and their willingness to direct some of it my way year after year. This sort of monitoring can yield tremendous insights into geomorphic processes, but requires patience and investments of time and money beyond a typical project length. I hope that, as a community, we can continue to find time and resources for this.

Niels, Jens and I thank you all again.