Oceanus_Procellarum

Resources of Oceanus Procellarum
by David Dietzler 2009

The Ocean of Storms offers interesting possibilities for resource utilization on the Moon. These resources might be of great value to lunar and Earth orbital industry in the future.

1) KREEP terrain. Some of the richest KREEP terrain exists in the Ocean of Storms. This could be a source of potassium and phosphorus, the two major fertilizer ingredients with nitrogen being the third, for agriculture. Potassium hydroxide could serve as a caustic for chemical processes. Phosphorus is indispensable for making solar panels. While p-type solar panel material might be made by doping silicon with aluminum instead of boron which is rare on the Moon, n-type material must be doped with phosphorus. We won't get very far on the Moon without electricity and we can't get solar panels without phosphorus so it seems reasonable that industrial bases should be located near KREEP terrain. However, it might be argued that solar thermal electric generation systems with aluminum or magnesium reflectors and titanium or steel boiler tubes and turbogenerators could be made anywhere on the Moon where Ca and Al rich highland regolith and Fe-Mg-Ti rich mare regolith are available such as a coastal location. Solar thermal electric systems reach 25% efficiency while silicon PVs are 10-15% efficient. Solar thermal systems are more complex therefore they require more maintanence. Presently it is not known whether silicon PVs or solar thermal systems offer more practicality and economy when it comes to making them on the Moon. Lunar manufacturing is still in its infancy. Hard data will be required to make this decision.

KREEP also contains rare earth elements. These REEs might be used for alloying iron, steel, aluminum, magnesium and titanium since many of the elements commonly used for alloying on Earth are lacking on the Moon. REEs are also used in many electronics applications and as catalysts. Their industrial uses are too many to be listed here. For more information, see: http://www.rareelementresources.com/s/Uses.asp

2) Pyroclastic glass. Volcanic glass, also called pyroclastic glass, is found in many places on the Moon. The largest deposit is in the Ocean of Storms just west of the Aristarchus Plateau (area 37,400 km^2).) Glass from volcanic fire fountains contains more chlorine, nickel, copper, zinc and gallium than is common in regolith and these elements can be obtained by roasting the glass particles [1]. The glass can also be reduced with hot hydrogen to gain oxygen. Chlorine is needed to extract aluminum by electrolysis, make silane and silicones, form silicon tetrachloride to obtain pure silicon for PVs, and table salt when combined with lunar sodium. Nickel is useful for iron and steel alloying and as a catalyst for shifting hydrogen and carbon monoxide to methane and water. Copper and zinc are used for alloying aluminum and magnesium respectively. Gallium can be combined with arsenic to make high efficiency solar panels.

3) Volcanic gas? This one is highly speculative. The Marius Hills in the Ocean of Storms contain over 200 low volcanic domes. Could there be intact chambers of volcanic gas there? Could this gas contain carbon monoxide, sulfur compounds, even water? Subduction zone volcanoes on Earth like the famed Mt. St. Helens emitt lots of water vapor from the ocean drawn under by geological processes. Hot spot volcanoes like Hawii also emitt water vapor from deep within the Earth though not as much as subduction zone volcanoes. The domes of Marius Hills will be more like hot spot volcanoes.

We will need lunar orbiters with powerful ground penetrating radars to investigate below the surface of the Moon. We will also need landers with geophones, sort of like underground sonar systems used to hunt for oil on Earth, and explosives or inert projectiles collided with the Moon to set up vibrations in the Moon that might reflect off of sub-selene formations including volcanic gas pockets. Then we will need robotic landers with drills that can tap this gas, should it exist, and analyze its composition.

If we found large quantities of CO, S compounds, even H2O beneath the Moon, this might be easier to tap by drilling than mining for ice in near absolute zero cold trap craters in polar areas. Carbon monoxide gas could be combined with lunar oxygen obtained by molten silicate electrolysis perhaps to make CO2 for CELSS. It could also be used for carbon for steel making, other metal extraction processes, even metal matrix composites like graphite/magnesium or silicon carbide/aluminum. Hydrogen from water could be combined with carbon to make some plastics. Sulfur could be used for sulfur concrete and sulfuric acid for metal extraction.

There is also the possibility that the Moon is "burping" radon from its interior. While radon is not very useful, its presence, should it exist, indicates the decay of uranium. Could the domes of Marius Hills exist because of large quantities of uranium below the surface decayed and released heat? Could there be more uranium and perhaps thorium too down below in richer deposits than KREEP which only contains about 4ppm U and 10 ppm Th? Since uranium decays to lead, could there be lead down there? Lead might not be useful as an industrial metal but it can be used to stain glass and get real red colored glass thus it would be valued by lunar artisans. Perhaps shaft mines could be dug with cabled teleoperated robots to get at these speculative deposits of uranium, thorium and lead.

While these sub-selene resources of volcanic gas and radioactives are mere conjecture at this time, the possibility of their existence is so tantalizing that we must investigate.

Location of a mining base or mining bases within the range of ground vehicles for access to the KREEP terrain, pyroclastic glass deposits and volcanic domes of Oceanus Procellarum will require more study. The base or bases should be located near a coast so that Fe-Mg-Ti rich mare regolith as well as Al-Ca rich highland regolith can be mined. Off road vehicle convoys and small gauge railroads will be needed; perhaps pipelines too. The base or bases would initially consist of an "industrial seed" of robotic mining, regolith refining and manufacturing devices that could self replicate using only lunar resources and small cargoes from Earth. Small human crews would supervise the robots. As the seed grows into full fledged smelters, factories and larger habitat more humans will go to the Moon. Industrial production will have to reach a scale at which millions of tons of materials were produced every year for a solar power satellite building project. Thousands of large helium 3 mining tractors would be built also. Scientific research, tourism, Moon made ships for asteroid mining and asteroid deflection forces to repel asteroids on collision course with Earth or our bases on the Moon, support for Mars colonization efforts in the form of metal for spaceships and propellant as well as equipment to be used on Mars mined and made on the Moon, and probably unforseen uses of lunar materials, will all emerge.

1] Cooper, B.L. (1994) Reservoir estimates for the Sulpicius Gallus region. Space 94: Engineering, Construction and Operations in Space, pp. 889-896. American Society of Civil Engineers, New York.