Times are displayed in (UTC-05:00) Central Time (US & Canada) Change

Apparent Hack’s Law in River Deltas

Session: Geomorphology and Surface Processes Across the Solar System

Presenting Author:

Tian Dong

Authors:

Dong, Tian Yang¹, Vulis, Lawrence², Ma, Hongbo³, Tejedor, Alejandro⁴, Goudge, Timothy Andrew⁵

(1) School of Earth, Environmental, and Marine Sciences, University of Texas Rio Grande Valley, Edinburg, TX, USA, (2) Department of Civil and Environmental Engineering, University of California Irvine, Irvine, California, USA, (3) Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, illinois, USA, (4) Institute for Biocomputation and Physics of Complex Systems, Universidad de Zaragoza, Zaragoza, Spain; Department of Civil and Environmental Engineering, University of California Irvine, Irvine, California, USA, (5) Department of Earth and Planetary Sciences, The University of Texas at Austin, Austin, TX, USA,

Abstract:

River deltas are densely populated, ecologically vital landscapes threatened by rising sea levels. Distributary Channel Networks (DCNs) disperse sediment to build deltaic land, yet their relationship remains elusive. Inspired by Hack’s Law that shows watershed drainage area scaling with channel length in Tributary Channel Networks, we analyze a global dataset of DCNs and discover a similar scaling between distributary channel length and nourishment area, the land-building counterpart to drainage area. Despite this apparent global scaling, we find two distinct local land-building patterns: Uniform Delta Networks consistently follow Hack’s Law, while Composite Delta Networks exhibit a scale break, transitioning from space-filling growth around the delta apex to linear growth near the coast. This unrecognized growth pattern offers insights into where delta restoration projects may be most effective.