Fluvial response to an historic lowstand of the Great Salt Lake, Utah

Abstract

Understanding fluvial adjustments to base level changes benefits the fields of sequence stratigraphy, geomorphology and petroleum geology. This investigation is a modern case study of the channel dynamics of Lee Creek and the Goggin Drain, two streams that are part of the Jordan River drainage into the endorheic Great Salt Lake of northern Utah, a lacustrine system that has experienced multiple, decadal-scale base level changes. Since 1965, the lake level has fluctuated in elevation more than 6 m, transitioning from an historic lowstand [< 1279 m above sea level (a.s.l.)] to an historic highstand (>1284 m a.s.l.), and in 2009-2010 approaching an historic lowstand. This study uses detailed aerial images, fieldwork and LiDAR data to link the modern geomorphology and channel hydraulics to specific variations in sediment transport, channel form, and avulsion behavior. Although Lee Creek and the Goggin Drain are situated only a few kilometers apart and share similar shore zone gradients, substrates and vegetation patterns, and have been subjected to the same changes in lake level, their channel forms have evolved very differently. Differences in discharge patterns are likely the most influential factor causing the meandering form of Lee Creek and the braiding channel of the Goggin Drain. Despite the differences in discharge, total sediment eroded from the two streams is comparable and can be attributed to similar stream power/unit stream width in the two streams. Although Lee Creek has not recently been avulsive, three major avulsions of the Goggin Drain have taken place since 1965. Two possible styles of avulsion are interpreted: an allogenic response to changing base level, and an autogenic response dictated by channel morphology and hydraulics. Despite a wealth of available information, avulsions cannot be unequivocally attributed to one style or another. Caution should be used when attempting to link the complex process of avulsion to causal mechanisms.

Log‐jams and avulsions in the San Antonio River Delta, Texas

“…Avulsions occur in aggrading systems and are thus common in deltas. Both internal or external conditions or forcings may promote or inhibit avulsions (see for example, Stouthamer and Berendsen, ; Taha and Anderson, ; Skorko et al , ). However, the specific location and timing of avulsions is not predictable, and is highly contingent on localized conditions and histories, and the timing of flood and other hydrogeomorphic events (Jones and Schumm, ; Makaske, ; Slingerland and Smith, ; Gouw, ; Phillips, , ).…”

Interpretación y cartografía de paleolíneas de costa lacustres mediante fotografías aéreas de alta resolución y datos LiDAR en la laguna de Gallocanta (NE España)

“…Los MDT obtenidos mediante datos LiDAR ayudan a una caracterización morfométrica de la superficie terrestre mucho más precisa, que puede dar lugar a mapas de gran detalle, así como a nuevas líneas y posibilidades de análisis morfométrico (Bishop et al, 2012). Más allá del obvio interés de los datos LiDAR para la ordenación del territorio o para la gestión de recursos y riesgos naturales (Raji et al, 2011;Saksena y Merwade, 2015), la topografía de alta resolución sirve también para la obtención automática de la geometría y curvatura del relieve (Tarolli et al, 2012), para analizar la hidrología superficial (Barber y Shortridge, 2005;Jones et al, 2008;Schumann et al, 2008;Skorko et al, 2012), o para el análisis morfodinámico de zonas costeras (Woolard y Colby, 2002;White y Wang, 2003;Raji et al, 2011;Benavente et al, 2013;Fernández-Núñez et al, 2017).…”

Geomorphic Response of a Low‐Gradient Channel to Modern, Progressive Base‐Level Lowering: Nahal HaArava, the Dead Sea

“…Stewart, 1996;Tucker & Whipple, 1999), or field surveys for kilometer-scale channel evolution on temporal scales of 10 2 -10 7 years (e.g., Crosby & Whipple, 2006;Haviv et al, 2010;Loget & Van Den Driessche, 2009;Törnqvist et al, 2006;Woolfe et al, 1998). Several studies have documented channel evolution at field scales associated with ongoing or recent base-level lowering for channel segments on the order of 10 2 to 10 3 m long (e.g., Adams, 2012;Ben Moshe et al, 2008;Hassan & Klein, 2002;Skorko et al, 2012;Storz-Peretz et al, 2011).…”

“…Reconstruction of an ancient longitudinal profile is rare and generally discontinuous on spatial and temporal scales, especially when determining the evolution of knickpoint position and shape (Loget & Van Den Driessche, 2009). Studies of recent field-scale channel evolution have the potential to fill this knowledge gap (e.g., Adams, 2012;Ben Moshe et al, 2008;Hassan & Klein, 2002;Skorko et al, 2012). They allow characterization of the external forcing and geomorphic response at relatively high spatiotemporal resolution based on diverse direct field measurements.…”

“…Channel response to base‐level lowering has previously been studied using experimental flumes (e.g., Begin et al, ; Brush & Wolman, ; Gardner, ; Grimaud et al, ; Holland & Pickup, ; Wood et al, ), numerical models (e.g., Begin et al, ; Ben Moshe et al, ; Bonneau & Snow, ; Leeder & Stewart, ; Tucker & Whipple, ), or field surveys for kilometer‐scale channel evolution on temporal scales of 10 2 –10 7 years (e.g., Crosby & Whipple, ; Haviv et al, ; Loget & Van Den Driessche, ; Törnqvist et al, ; Woolfe et al, ). Several studies have documented channel evolution at field scales associated with ongoing or recent base‐level lowering for channel segments on the order of 10 2 to 10 3 m long (e.g., Adams, ; Ben Moshe et al, ; Hassan & Klein, ; Skorko et al, ; Storz‐Peretz et al, ).…”