Monday, May 29, 2017

Highlights: The Shape of Sand

Interpreting depositional setting is a fundamental task of many sedimentary geologists.  Existing analytical techniques using sediment properties to characterize depositional setting and related mechanism of transport can produce results with varying accuracy or can be cost prohibitive. Here, Eamer and co-workers describe a new method that uses freely available software and an optical microscope to differentiate coastal sands transported by eolian and littoral processes. The method is based on the principle of eolian sand sorting, in which wind preferentially transports rounded grains to angular grains. The software was used to classify grain solidity. Results from application of this method are promising, with correct identification of the transport mechanism of 76% of nearly 6000 tested sand grains. Determining the depositional setting of sand grains provides important information for paleoenvironmental reconstruction, stratigraphic interpretation, and applied sciences (e.g., hydrogeology).

Distinguishing depositional setting for sandy deposits in coastal landscapes using grain shape by Jordan Blair Reglin Eamer, Dan Hirsh Shugar, Ian James Walker, Olav B. Lian, and Christina M. Neudorf

Friday, May 26, 2017

Highlights: Good (Tidal) Beach Reading

Tide-dominated beaches are widespread in today's world, and coastal researchers have recently begun to address their sedimentary character, finding that they differ notably from the more familiar, purely wave-dominated beaches. Nonetheless, ancient tide-dominated beaches are infrequently recognized, perhaps for want of suitable sedimentological criteria and facies models. Smosna and Bruner present the facies reconstruction of The Cambro-Ordovician Cabos Formation of northern Spain, a system interpreted to represent an ancient tide-dominated beach system. In describing sedimentologic observations and the criteria on which the interpretation is based, this analysis constitutes a beginning step in constructing the sedimentological framework for a virtually unknown (or at least poorly documented) paleoenvironment. 

Friday, May 19, 2017

Highlights: Sources in the Chaco

Foreland basins are the ultimate sink for much of the sediment derived from erosion of fold-and-thrust belts in convergent margins. To better understand the evolution of the Andean cordillera, and convergent-margin syn-orogenic sediments in general, McGlue and others integrate geomorphological observations with analyses of composition, texture, and U-Pb ages of modern detrital sediments of the Río Bermejo megafan in the Chaco foreland basin, northern Argentina. The results document that provenance reflects the lithology of the parent material and the transport distance, with maturity increasing farther from the thrust front and sediment fining towards the forebulge. These data enhance understanding of distributive fluvial systems in overfilled retroarc foreland basins, and may improve interpretation of ancient analogs that have been the source of critical information on the history of convergent orogenic belts. [Editor’s note: other Chacos are interesting as well.]

An integrated sedimentary systems analysis of the Río Bermejo (Argentina): megafan character in the overfilled southern Chaco foreland basin by Michael M. McGlue, Preston H. Smith, Hiran Zani, Aguinaldo Silva, Barbara Carrapa, Andrew S. Cohen, and Martin B. Pepper

Tuesday, May 16, 2017

Highlights: Unraveling Unroofing in the Piceance

As numerous JSR papers have illustrated, sediment provenance can provide key insights for interpreting climatic controls on stratigraphy, estimating paleoaltimetry, and reconstructing the timing and mechanisms of tectonic processes; after all, there are various causes for unroofing. Here, Foreman and Rasmussen examine the provenance of sediment the Wasatch Formation exposed in the Piceance Basin of Colorado to explore the unroofing history of surrounding uplifts. Integrating new and compiled paleocurrent measurements, sandstone petrographic compositions, and U-Pb detrital-zircon ages, the results refine unroofing history and revised age constraint for the Sawatch (Laramide) Range.  The data provide new perspectives on mechanisms behind the shift from Sevier to Laramide tectonism, and at a finer scale, implicate major shifts in deposition within the Wasatch Formation related to fluctuations in tectonics and climate.

Tuesday, May 9, 2017

Highlights: JSR: Jammin’ Speedy Results

Although most authors (ultimately) appreciate of the rigorous editorial process at JSR, many may not realize that JSR currently has no backlog for getting accepted manuscripts to publication

What exactly does that mean for authors?  In short: Quicker publication. 

To provide perspective: your humble blogger and a student had a manuscript that was accepted for publication in another well-respected society journal in September, 2016.  We were told it would appear in press in May 2017 (!!)...but we just heard that “oops we meant August 2017...maybe.”  That’s a year delay!  Likewise, another competitor journal lists dates of acceptance online. Their most recent issue (April 2017) shows that some manuscripts that were accepted in August 2016 just now have their official final version published.

In marked contrast, manuscripts at the Journal of Sedimentary Research accepted for publication in April 2017  will appear in their final published version online in May 2017!  A matter of a few weeks!  Yowzah – Speedy Gonzales!  

Now to be fair, faster is not always better, and sometimes fast can be “too fast” and get you in trouble. And of course, there are some different (eh?) and interesting ways to speed up things. Some other journals post accepted manuscripts online early, but that’s “kind of” a pre-publication, but, as savvy JSR PaperClip readers know, you can see a lot of fake stuff on the internet.

But wouldn’t you just rather see your accepted manuscript published for real sooner than later?!  Submit it to JSR.

Thursday, May 4, 2017

Highlights: Zany Zircons Mix It Up

Provenance data from sand-sized sediment is an important tool in sedimentology, tectonics and structural geology. To understand the role of sedimentary process in controlling provenance signatures in sand-sized sediment at the scale of entire sediment dispersal systems, Sickmann and others explore U-Pb detrital-zircon data from a series of modern second-order river-to-deep-marine depositional systems in central California. The results illustrate that changes in provenance signatures from sand-sized sediment across dispersal systems and between dispersal systems potentially are influenced by sedimentary processes - and not by tectonic evolution of sources or the evolution and expansion of drainage basins as commonly assumed. These data emphasize understanding the potentially important role of sediment mixing in the marine realm, systems with changes in sediment pathways that can create variable pathways.

Monday, May 1, 2017

JSR Outstanding Paper 2015

This April at AAPG, SEPM announced the winner of the Outstanding Paper Award for JSR. The award is determined through a combination of nominations and votes from the editorial board and a metric of citations from GeoScienceWorld. We are very happy to present the OP award for 2015 (yes, we know we are behind a year) to three papers!

Gary J. Hampson, Robert A. Duller, Andrew L. Petter, Ruth Robinson, and Philip A. Allen


Ted E. Playton and Charlie Kerans

Congratulations to our winners!