Today's 16-mile hill and coast ride took me to the top of Poinsettia Lane, then down to the Coast Highway. Lost ~400 ft of hard-earned vertical on the always fun Poinsettia descent.
Since we've been talking about sea cliff retreat, I snapped this shot of the failing cliff between the swanky Alila Marea resort above and South Ponto Beach below.
The deeply gullied reddish upper layer is the Bay Point formation — a weak, poorly lithified sandy mudstone around 2 million years old. This badlands-style erosion is a sure sign of soft rock. Not proving to be a great foundation for the resort.
Showing directly beneath the Bay Point at the bottom of the cliff is the much stronger tan Torrey Pines sandstone, some 45 million years old. Loose cobble eroded from very hard ~130 million year-old volcanic rock some 150 mi inland protects the Torrey Pines from most wave impacts but not all.
What happened here during the missing 43 million years of geologic record between the Bay Point and Torrey Pines layers is anyone's guess.
View north from the resort. You can see why they wanted to put a resort on this vantage point, but there have already been some small slumps around the perimeter.
Love watching late afternoon sunlight play on and through the waves.
Gratuitous glamour shot. What a pleasure this thing is to ride!