Spheroidal and honeycomb weathering
One of the beaches we frequent, off the beaten track and commonly deserted, has at its south end cliffs of […]
In the field
How to read a sea level curve
Changes in sea level, or baselevel, are central to all forms of genetic stratigraphy. Shorelines migrate basinward or landward because
Facies and facies models
Facies and facies models are fundamental tools for sedimentology and sequence stratigraphy. This is part of the How To…series on
Baselevel, base-level, and base level
Baselevel is a datum. This is part of the How To…series on Stratigraphy and Sequence Stratigraphy Baselevel is a datum.
All the Stratigraphies
Preamble: This post outlines the development of formal stratigraphy, focusing on Chronostratigraphy. Entire books have been devoted to this topic; one of the most entertaining and enlightening is Martin Rudwick’s excellent account of the conduct of 19th century gentlemen who argued the case for the Devonian. My account is woefully brief, but there you have […]
Volcanics in outcrop: Pyroclastic fall deposits
A look at volcaniclastics – pyroclastic fall deposits in outcrop This is part of the How To… series on describing
Mineralogy of carbonates: Stromatolite reefs
An example of a Paleoproterozoic stromatolite reef This is part of the How To…series on carbonate rocks Reefs are the
Sedimentary structures: Stromatolites
A look at stromatolites and cryptalgal laminates in outcrop This is part of the How To…series on describing sedimentary rocks
Mount St. Helens: 40th anniversary
May 18, 1980, a crisp, clear Cascade mountains morning was rent by the catastrophic eruption of Mount St. Helens.
Volcanics in outcrop: Secondary Volcaniclastics
A look at reworked volcaniclastics in outcrop This is part of the How To… series on describing rocks that in