Koko Crater Photos

The following photos were taken by me, (Nathan Yuen) on Thursday, March 26, 1998 during a hike to expore the fascinating rock formations of Koko Crater and the geology of the region.

Koko Crater is the horseshoe-shaped volcanic crater on the Kaiwi Coast with an opening on its northeast side. Koko Crater is the highest and most prominent of the series of volcanic vents that are oriented in a northeasterly line along the coast which includes Koko Head, Hanauma Bay, Kahauloa Crater, Kalama Crater, Manana (Rabbit Island), and Kaohikaipu (Manana's low-lyng companion).
From Sandy Beach one can easily see the odd-looking dark-colored rock formations, sometimes called parasol ribbing which appear to hang precariously off the outside of the crater rim. Made when the soft light-colored layer of tuff (welded ash) eroded away from beneath the hard dark-colored layer at the surface, these unusual ledge-like formations can be found in many places in the crater.
Starting my exploration from Blow Hole at Halona Point, I was fortunate to see the waves crash the against the rocks, create pressure beneath the rocky ledge, and force plumes of mist out the hole high into the air! Here is a shot from way off on Sandy Beach of a white plume of water emanating from Blow Hole and small one from close-up. Here is a picture of the charming little cove at Halona Point.
As I started the ascent through the small valley just opposite the cove, I could plainly see the many layers of tuff and the sparkle of olivine crystals in the rocks. When I reached the end of the valley, the natural bridge off in the distance came into view. The arrow in this picture shows the dark-colored rock of the natural bridge over the soft light-colored rock which eroded away over the passage of time. When I reached the hole under the arch, I noted that the hole is about 30 feet long and 8 feet high, and oriented at an angle of what must be about 45 degrees. The dark-colored hard rock above the hole which forms the bridge is about 8 feet wide and 6 feet thick. Here is a shot of the higher end of the arch. Here is a shot of the lower end of the arch.
As I reached the lip of the crater, a strong wind greeted me. Blowing in strong gusts, I clung to the rocks at several of the more harrowing spots along the rim. Here is a shot of the opening in the northeast wall from ontop the crater. Here is a shot of Blow Hole, Halona Point, and the Cove from high above.
When I reached Pu'u Ma'i, the highest point on the crater, Hanauma Bay sparkled magnificently below in the sunlight as its shallow green, azure, and teal waters melded into the deep blue waters of the ocean. What a beautiful sight!