3. The emergence of organic compounds from the interactions between land, sea, air, and sunlight
3.1. Rocks and minerals
Using the method outlined in section 1.1., wc extracted minerals from six types of rocks: (a) granite, a typical rock found in the upper crust; (b) orthociase, a component mineral of granite; (c) basalt a typical rock found in the earth's lower crust; (d) enstatite, a component mineral of basalt; (e) olivine, the principle rock-forming mineral of the upper mantle; and (f) diopside, a calcium-rich mineral found in pyroxenite.
We selected these rocks and minerals to help us understand which types of organic compounds can be obtained from the mineral solutions extracted from them.
3.2. Methods and materials
There are pioneering studies, such as Miller [5], which concern the emergence of organic compounds from inorganic compounds. However, we have focused our experiments on the birth of life on the earth not under extreme conditions of pressure and temperature, but in a normal atmospheric environment in the present age. We conducted tests to see what would happen in the interaction of land, sea, primeval air, and sunlight by dissolving gas that represents the primeval atmosphere, in a mineral solution and generating photoreactions. To speed up the reaction time, we used ultraviolet light (low-pressure mercury lamp) instead of sunlight. Figure 10 shows the reaction apparatus used in our experiments. The 1-liter reaction tank was made of high-purity quartz glass. We filled this tank with 800 cc of pure water (18.25 M) and then added minerals extracted from the rock and mineral specimens mentioned above. The mineral concentrations were varied from several ten to several hundreds ppm. This solution was subjected to 10 h of bubbling with high-purity gas (CO2:N2 = 1:1) that resembled the primeval atmosphere, after which it was exposed to ultraviolet light for 100-500 h. We did the same experiment but used a high-purity gas mixture (N2:O2:CO2 = 7:2:1) that resembles the present-day atmosphere.
Table 2 shows the quantitative analysis of the solutions. Alcohols and certain aromatic hydrocarbons were easily synthesized from the granite and orthoclase, and aromatic hydrocarbons were readily obtained from diopside. From basalt, enstatite, and olivine, important organic compounds for life were readily synthesized, including the precursors of amino acids, fats, sugars, and certain nucleic acids and the components of nucleic acid. Basalt, enstatite, and olivine are substances found in or adjacent to the mantle, and are characterized by their extremely high phosphorus (P) content, as compared with other types of rock such as granite. This high P content caused the synthesis of ADP and ATP, which are within the components of nucleic acids. This implies that when life first appeared on the earth, intensive volcanic activity caused vast quantities of basaltic lava to flow into the sea.
