Baja California
The second day of the Sea Bird's journey in the Gulf of California began with a perfect dawn as we lay anchored near Isla San Ildefonso. The sun rose behind thin wisps of high clouds that glowed with orange color above a tranquil sea. Zodiacs were launched just as the sun reached the horizon and we boarded for a exploration of the rugged coast.San Ildefonso is underlain by silica (SiO2), poor volcanic rocks known as basalt. These rocks are quite dissimilar to the silica rich volcanic rocks that we see on most of the Gulf islands. The contrasting chemistry of the silica rich and silica poor volcanic rocks or bimodal chemistry is typical of volcanic rocks found in areas where the Earth's crust has been rifted by tectonic forces. Numerous fractures and faults could be seen cutting through the rocks on the island -- many of these are red with iron staining or white with calcite or silica precipitate -- evidence for fluid movement through the broken rock. The eastern cliffs include large bulbous extrusions of lava or 'pillows' -- evidence for extrusion of the lava into water. Faults and overall heterogeneous nature of the basaltic volcanic rocks have allowed waves to sculpt them into a near honeycomb maze of steep cliffs, rugged inlets, and small caves.
During our Zodiac cruises we were treated to the sight of numerous Cormorants, Blue and Brown-Footed Boobies, Pelicans, Sally Lightfoot crabs. In addition we were treated to views of a Wandering Tattler on the shore line, a lone American Oyster Catcher also on the shore, and a Frigate bird flying over the boat. Some of us also glimpsed a sea lion swimming along the shore. A wonderful way to start the day!
The second day of the Sea Bird's journey in the Gulf of California began with a perfect dawn as we lay anchored near Isla San Ildefonso. The sun rose behind thin wisps of high clouds that glowed with orange color above a tranquil sea. Zodiacs were launched just as the sun reached the horizon and we boarded for a exploration of the rugged coast.San Ildefonso is underlain by silica (SiO2), poor volcanic rocks known as basalt. These rocks are quite dissimilar to the silica rich volcanic rocks that we see on most of the Gulf islands. The contrasting chemistry of the silica rich and silica poor volcanic rocks or bimodal chemistry is typical of volcanic rocks found in areas where the Earth's crust has been rifted by tectonic forces. Numerous fractures and faults could be seen cutting through the rocks on the island -- many of these are red with iron staining or white with calcite or silica precipitate -- evidence for fluid movement through the broken rock. The eastern cliffs include large bulbous extrusions of lava or 'pillows' -- evidence for extrusion of the lava into water. Faults and overall heterogeneous nature of the basaltic volcanic rocks have allowed waves to sculpt them into a near honeycomb maze of steep cliffs, rugged inlets, and small caves.
During our Zodiac cruises we were treated to the sight of numerous Cormorants, Blue and Brown-Footed Boobies, Pelicans, Sally Lightfoot crabs. In addition we were treated to views of a Wandering Tattler on the shore line, a lone American Oyster Catcher also on the shore, and a Frigate bird flying over the boat. Some of us also glimpsed a sea lion swimming along the shore. A wonderful way to start the day!
