Please ensure Javascript is enabled for purposes of website accessibility

Category : Science Spotlight

Posted : Monday, November 27, 2023
Edited By : Sean Brown
Tuesday, November 28, 2023

Science Spotlight: TSR + Clark Gilbert

Rebekah Grmela

Welcome to our member and publication highlight series: the SEPM Science Spotlight! 

This series is a feature that enables SEPM members to dig in deep and learn more about the work of their members and SEPM publications. Read below to learn more about a recent work in SEPM's The Sedimentary Record journal, and contact Clark to talk science! 

Would you like your work featured? Consider applying here or submitting your info with your next SEPM journal submission. 


NameJ Clark Gilbert
Geologist, Bureau of Reclamation, Engineering Geology and Geophysics Group, Technical Service Center in Denver, CO. 
PhD from Colorado School of Mines, M.S. from Wichita State University and B.S. from Sewanee.

PublicationThe Sedimentary Record

Title of PaperSubmarine-Channel Element Architecture Demonstrates Facies Heterogeneity in Both Strike and Dip Views: Miocene Modelo Formation, Lake Piru, California, USA

Authorship of PaperJ Clark Gilbert and Zane R Jobe

New insights and global importance of the study, a summary of results and methods used to achieve them, and major outcomesSubmarine channels deliver vast quantities of sediment into ocean basins and the deposits left by these systems host important archives of paleoenvironmental change and are major targets for hydrocarbon production and carbon sequestration. However, similarities between channel subenvironments often make their identification difficult, particularly because some subenvironments are transitional or quite variable. While large channel complexes can often be resolved on seismic data, only outcrop data yields high-resolution detail of their internal heterogeneity. This study integrates 10 measured sections with drone-based photography to document lateral and vertical changes in depositional architecture in a well exposed outcrop of a submarine-channel element in the Miocene Modelo Formation at Lake Piru, California.

The channel-element architecture is well constrained by erosional-surface mapping and lateral and vertical facies changes. The 3-dimensionality of the outcrop provides a unique example to demonstrate this heterogeneity in both strike (i.e., cross-sectional view) and dip orientations (i.e., longitudinal view). This channel element has a predictable vertical facies succession of thin sandstones and mudstones, mass transport deposits and amalgamated sandstones. The element is capped by a siliceous mudstones that provide a unique marker of hemipelagic deposition and the presence of an abandonment surface. The amalgamated sand packages are thickest in axial locations and thin over a distance of 500 m in the dip direction, but thin over 150 m in the strike direction toward two locations along the same margin. This thinning is used to constrain the dimensions and sinuosity of the channel element. We interpret a channel-element width of 550 m, a thickness of 29 m and an aspect ratio of 19:1, which is in agreement with previously published ranges of channel-element dimensions. With the documentation of lateral facies heterogeneity in orientations slightly oblique to both strike and dip, this study provides important data for understanding channelized sediment gravity flow dynamics in submarine channels and aids in evaluating reservoir-model volume and connectivity estimates.

"SEPM and its members have always been supportive of my research through grants, conferences and publication in the Sedimentary Record. I am honored to have my PhD research showcased by such a great organization."

More about Clark: Former Student Liaison for the Rocky Mountain Section of SEPM. My research quantifies how sediments fill basins and uses that depositional record to interpret changes in tectonics or sediment routing. I have used detrital zircon geochronology, automated mineralogy, X-ray fluorescence, drone photogrammetry and data science methods in Python to build depositional models that quantify these changes. I now build 3D models of the surface and foundation geology of dams around the western U.S. for the Bureau of Reclamation to investigate seepage issues and potential seismic and landslide hazards."   

Where you can learn more: You may  reach out to Clark (or Zane Jobe) via Twitter or email here