Abalone Cove

This southern shore of the Palos Verdes Peninsula has a bit of a geological reputation - and not just because of its Tertiary sediments, Pleistocene marine terraces, and late Holocene cobble beaches. I first heard about Portuguese Bend in college in the context of large deep-seated landslides (and the ramifications for continuing to develop them long after the risk was recognized, as I recall). I guess the Portuguese Bend slide is perennially on the move. The impacted stretch of Palos Verdes Drive is a roller coaster with warning signs, unexpected dips, and patched asphalt. The waterlines are on the surface, which I suppose makes them easier to inspect and repair.

AERIAL VIEW

Abalone Cove is in the western portion of this messy geology. Part of it was active in the 1980s, although I guess that involved only a small area of a much larger landslide complex that extends far into the local hills. Interestingly, Wayfarer's Chapel, just up the hill from here, must be on more stable ground, as it's been there since at the early 1950s and remains intact.

The central portion of the Abalone Cove beach is armored with old concrete rubble, the lower parts of which were rounding into conglomeratic cobbles. But there were also much more appealing natural cobble beaches in both directions. By the way, that what makes these beaches more appealing isn't just that the cobbles lack rebar, but that there is still an upper beach, whereas on the armored section (as on armored beaches pretty much everywhere), the back beach is pretty much buried under the armor itself.

The bluff that rises behind the beach shows both the topography and the twisted stratigraphy typical of big landslides.