Monday, 30 May 2016

The Pisgah Crater, California

Pisgah Crater, or Pisgah Volcano is a volcanic cinder cone in the Mojave Desert between Barstow and Needles, California United States. Pisgah Crater is in the Craters category for San Bernardino County in the state of California. The volcanic peak is about 2.5 miles, had a historic elevation of 2,638 feet. Although, mining activities has reduce the peak lit bit, but had a severe environmental impact. A Canadian based company “Can-Cal Resources Limited” presently owned the mountain specializes in exploration of precious minerals in California. The site of the Mount Pisgah Volcanic Cinders Mine, that produced pumice for commercial use and various cinder products, and sand was used to depict black sands of Iwo Jima in the film Letters from Iwo Jima. Moreover, the mountain top has been removed and scoured into an irregular shape.

Due to natural erosion and mining operation the crater has lost of must its original cinder cone shape. The base diameter of Pisgah Crater is 488 meters and stands 98 meters above the surrounding high desert terrain. Furthermore, the mountain contains a large number of lava tubes, which are frequented by cavers and, these lava tubes in the area are a bit popular and with no trouble accessible destination for caving. However, no authentic data available when Pisgah Crater was last erupted, but many geologist, believes, Pisgah Volcano is the youngest vent of four cinder cones, may have been activity more than 2,000 years ago. Though, many others believe the last eruption could be occurred around 30,000 to 50,000 years ago. The volcano is basaltic, a reliable commonly used potassium-argon for dating purpose would be difficult anyway. A similar nearby Amboy Crater is interbedded with Bristol Playa sediments are somewhere 100,000 years old.
This volcano is very popular geology research site, not uncommon to find university classes and professional seminar groups around the mountain, geological survey activity also occurs at the mountain every so often. Moreover, the volcano erupted at least three times, produced porphyritic basalt, rocks from the first eruptive phase are almost aphanitic. The lava found around the volcano consists of a'a and pahoehoe, with considerable concentrations of olivine, plagioclase and rich amounts of gypsum can be found coating rocks near the cinder cone. The Pisgah Lave Field is located in a valley, with the Cady Mountains (Sleeping Beauty Mountains) to the north, looks like a lady lying on her back with her long dark hair trailing off to the east.

Therefore, the first eruption was a basaltic flow created extensive lava fields, and evidence of intrusive structures, it is believed the cinder cone was formed during this time. The second phase produced similarly extensive flows, while the third eruption produced substantial amounts of tephra. It is believed that most of the present cinder cone consists of pyroclastic material that originated from this final eruption. Well, On the Halfway up, there’s a dark hill called Sunshine Crater Cinder Cone distinctly older than Pisgah Crater, are off limits because they are within the 29 Palms Marine Base. Mount Pisgah name is derived from Bible, is described as a peak on Mount Nebo.