Twenty-one years ago I drove across the great plains and southwest deserts of the United States on my way to California. Iraq had just invaded Kuwait and gas prices soared. I made a note of the highest price: $1.79 per gallon in Amboy California, which is near the southwest portion of the mojave desert. While in Amboy, I noticed a lava flow and prominent cinder cone and vowed to return. Twentyone years and over 2 dollars per gallon later, I returned.
Amboy Crater, viewed from the western rim (spliced together from three photos)
The drive north from Joshua Tree National Park to Amboy crosses classic alluvial fans. These alluvial features evelope the base of the mountains and form vast gradual slopes where you can drive for miles, barely noticing any elevation change.
The cinder cone rises 250 feet from the surface, making it unmistakable:
A mile-long trail leads from a parking lot to the cone and crosses the lava flow and it's varying features. Here, the flow's low, wavy shape is highlighted by the dry grass:
And here the texture is that of a pushed up parking lot, rock black as asphalt and cracked. Plants and sand exploit the cracks.
The composition of the cone has texture differences. Right is crumbly; and left, more of a charcoal color and texture comparable to graphite powders. The left also has distinct erosion channels.
A view looking down from the crater rim near the transition between textures.
A close up of the texture change:
After my visit, I found Amboy Crater on GoogleEarth, which is just like being there, unless of course, you've actually been there.
Notice the satelite photo from GoogleEarth shows streaks from the cinder cone and other features. These streaks weren't apparent to on the ground, and if they are real, my guess is that the streaks are wind deposits, darker grains blown from the cinder cone and other outcrops, and deposited onto the sand dusted flow. It is likely the winds blow consistently to the south east, something to follow up on.
Something on the sparse wildlife:
A very unusualy insect, unless I presume, you live here.
And a few plants:
Possibly a mallow or type of lilly growing among the lava rock -- another plant to identify.
Bright yellow encelia bushes peak around March and make a delightful contrast with the dark rock.
One last note: The best time to visit is Oct - March when the temperatures are mild. The lava flow heats up in the sunlight and would be dangerous for most people to cross when April-Sept temperatures start in the 90s.
I use this blog as a companion to my website www.brightstarstemeculavalley.org, where I call attention to local light pollution and share my enthusiasm for science and astronomy. I'm also a contributor to www.SkepticalScience.com.