Saturns equinox rings ice wall B


A stunning image of Saturn’s B ring, near the last Saturn equinox, with what appears to be a wall of material that goes vertical for over 2 kilometres. The rest of the B rings normal height is suggested to be only 10 meters (30 feet) high.

Vertical structures, among the tallest seen in Saturn’s main rings, rise abruptly from the edge of Saturn’s B ring to cast long shadows on the ring in this image taken by NASA’s Cassini spacecraft two weeks before the planet’s August 2009 equinox. Part of the Cassini Division, between the B and the A rings, appears at the top of the image, showing ringlets in the inner division.

Cassini’s narrow angle camera captured a 1,200-kilometer-long (750-mile-long) section arcing along the outer edge of the B ring. Here, vertical structures tower as high as 2.5 kilometers (1.6 miles) above the plane of the rings – a significant deviation from the vertical thickness of the main A, B and C rings, which is generally only about 10 meters (about 30 feet).
The Tallest Peaks | NASA Cassini

Are they a variation of clouds in the upper atmosphere or am I just looking for that sort of thing? Wind (current) streaked formations? Icy dusty plasmas, energised layers, flows, transformers …

Images like this are only possible around the time of Saturn’s equinox, which occurs every half-Saturn-year, or about every 15 Earth years. The illumination geometry that accompanies equinox lowers the Sun’s angle to the ring plane and causes structures jutting out of the plane to cast long shadows across the rings.
Saturn’s B ring peaks | European Space Agency

The dark grey spikes are the clouds shadows? Are they down into the material and seen through it or the shadow cast onto the ‘wall’ surface?