Jim Elder

Ottawa, Canada


Mesquite Flat Sand Dunes, Death Valley, USA

Geology: Sand & Dunes


Aeolian dunes and sandstone: Overview (intro, including animations)

Strata dip and thickness: True and apparent (including phone-compatible tools)

Numerical Models

Dune field morphology (model of migrating bedforms)

Model of stratigraphic bounding surfaces produced by migrating bedforms (stratigraphy)

Sampling dune sand (effect of sampling on grain-size distribution results)

Observations & Interpretations

Grainflow/avalanching, vortices, grainfall at Coral Pink Sand Dunes State Park, USA (videos)

Grainflow/avalanching (video)

Thin sections of grainflow with pinstripes

Cornice deposit (grainfall lee of the brink)

Sand micrographs (photos of sand grains); stereogram of Navajo sand grains

Air flow in the lee of a dune (recirculation cell)

Grainflow (slipface avalanche deposits)

Cross-sectional profile of some avalanche tongues/troughs

Coral Pink Dunes State Park, Utah, USA:

Dune migration (analysis of Google Earth imagery)

Stoss slope trenches (internal dune structure)

Serial sections (image stacks for 3D reconstructions) of rock samples:

Kanab Goldenstone (Triassic Shinarump Formation; Utah USA)

Iron-oxide concretion A (Jurassic Navajo Sandstone; Utah USA)

Iron-oxide concretion B (Jurassic Navajo Sandstone; Utah USA)


Making pinstripe laminae visible in dry sand (a refinement of Bagnold's water seep method)

Measuring cross-sectional profiles of dune features (using the shadow of a straight-edge)

Detecting subsurface slipface shear (using a sand column of contrasting colour)

Making air flow visible (using simple streamers)

Making sand flow visible using an adapted Hele-Shaw cell

Measuring dip (eg., angle of repose)

Photographic reference scale (for scale, colour, and perspective)

Protecting photographic gear from blowing sand

Enhancing low-contrast photos (post-processing to improve visibility)

Serial sectioning to obtain images for 3D reconstruction (using a rock saw)

Particle analysis: Obtaining representative subsamples (spinning riffler)

Journal articles, conference posters

Elder & Loope at Coyote Buttes, USA. Volume 25 (2), 2009

Backwasting rock sheets of the Navajo Sandstone, Utah, USA
DB Loope, JF Elder, VA Zlotnik, GR Loope, D Blythe
Earth Surface Processes and Landforms 47 (10), 2628-2642

Jurassic earthquake sequence recorded by multiple generations of sand blows, Zion National Park, Utah
DB Loope, JF Elder, VA Zlotnik, RM Kettler, DT Pederson
Geology 41 (10), 1131-1134

Downslope coarsening in aeolian grainflows of the Navajo Sandstone
DB Loope, JF Elder, MR Sweeney
Sedimentary Geology 265, 156-162

An 8-event Jurassic earthquake sequence of ~1 yr duration recorded by clastic pipes and dikes within dune cross-strata, Zion National Park, Utah
DB Loope, JF Elder, VA Zlotnik, RM Kettler, DT Pederson
Geological Society of America Abstracts with Programs 44(7), 547, 2012/11/7
2012 GSA Annual Meeting, Charlotte

Origins of pinstripes and grainflow strata in eolian sandstones: Lessons from the Navajo Sandstone at Coyote Buttes, Arizona-Utah
DB Loope, JF Elder
2007 GSA Annual Meeting, Denver

Eolian pin stripes in the Navajo Sandstone: Two distinct modes of origin
DB Loope, CW Zanner, JF Elder
2005 GSA Annual Meeting, Salt Lake City

Boundary between two sets of aeolian cross-strata, Paw Hole, Utah (Navajo Sandstone)