Procellarum KREEP Terrane The Procellarum KREEP Terrane, or PKT, is a large province on the near side of the Moon that has high abundances of KREEP. KREEP is an acronym built from the letters K (the atomic symbol for potassium), REE (rare-earth elements) and P (for phosphorus), and is a geochemical component of some lunar impact breccia and basaltic rocks. Notably, it is high in thorium, a rare earth element, distinguishing it from the other terranes. The PKT is on the near side of the moon, and covers 16 \% of the lunar surface  . Despite this, it contains 60\% of all basaltic flows. KREEP has been shown to lower the melting point of rocks similar to those found on the Moon, and is expected to have contributed to volcanism in the region.  The inner FHT lies exclusively in the far side of the Moon, whereas the outer FHT spans both sides and is the one of two terranes on the near side of the Moon, along with the PKT. No spacecraft have landed on the inner FHT, as the only lander to the far side touched down in the South Pole-Aitken Terrane. In contrast, the outer FHT has been the subject of human landings and sample return. South Pole-Aitken Terrane The South Pole-Aitken Terrane, or SPAT, may simply represent deep crustal materials of the Feldspathic Highlands Terrane. It has thorium levels between those of the PKT and FHT. The SPAT can be divided into two terranes, an outer and an inner SPAT. The outer SPAT has less iron oxide and thorium than its inner counterpart, although the thorium levels are still between those of the PKT and FHT. The terrane has its origins in a large impact that occurred early in the Moon's history and which had a major impact on the Moon's thermal evolution  .
Procellarum KREEP Terrane The Procellarum KREEP Terrane, or PKT, is a large province on the near side of the Moon that has high abundances of KREEP. KREEP is an acronym built from the letters K (the atomic symbol for potassium), REE (rare-earth elements) and P (for phosphorus), and is a geochemical component of some lunar impact breccia and basaltic rocks. Notably, it is high in the KREEP element thorium, at a level of 4.8 ppm. This is a major factor distinguishing it from the other terranes. The PKT is on the near side of the moon, and covers 10 \% of the lunar surface , or 16\% if one includes the maria lying within the FHT . Despite this, it contains 60\% of all basaltic flows. KREEP has been shown to lower the melting point of rocks similar to those found on the Moon, and is expected to have contributed to volcanism in the region. Overall, 6\% of the lunar surface (and hence 9\% of the FHT) consists of maria within the FHT, such as Mare Moscoviense. FHT maria have on average only 2.2 ppm of thorium, which is twice as much as the lunar average but significantly less than the levels seen in the PKT maria. Outer FHT non-maria regions contain 1 ppm of thorium, and only 0.3 ppm of thorium in the inner FHT. The inner FHT lies exclusively in the far side of the Moon, whereas the outer FHT spans both sides and is the one of two terranes on the near side of the Moon, along with the PKT. No spacecraft have landed on the inner FHT, as the only lander to the far side touched down in the South Pole-Aitken Terrane. In contrast, the outer FHT has been the subject of human landings and sample return. South Pole-Aitken Terrane The South Pole-Aitken Terrane, or SPAT, may simply represent deep crustal materials of the Feldspathic Highlands Terrane. It has thorium levels between those of the PKT and FHT. The SPAT can be divided into two terranes, an outer and an inner SPAT. The outer SPAT has less iron oxide and thorium than its inner counterpart, although the thorium levels are still between those of the PKT and FHT. The terrane has its origins in a large impact that occurred early in the Moon's history and which had a major impact on the Moon's thermal evolution . The SPAT corresponds to the darker region in the far side of the moon. The inner and outer SPAT cover 5.3\% and 5.7\% of the lunar surface, respectively. Despite collectively covering 11\% of the surface, SPAT contains only 5.8\% of the thorium in the lunar crust .
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thorium, a rare earth element,
the KREEP element thorium, at a level of 4.8 ppm. This is a major factor
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16
10
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, or 16\% if one includes the maria lying within the FHT
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Overall, 6\% of the lunar surface (and hence 9\% of the FHT) consists of maria within the FHT, such as Mare Moscoviense. FHT maria have on average only 2.2 ppm of thorium, which is twice as much as the lunar average but significantly less than the levels seen in the PKT maria. Outer FHT non-maria regions contain 1 ppm of thorium, and only 0.3 ppm of thorium in the inner FHT.
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. The SPAT corresponds to the darker region in the far side of the moon. The inner and outer SPAT cover 5.3\% and 5.7\% of the lunar surface, respectively. Despite collectively covering 11\% of the surface, SPAT contains only 5.8\% of the thorium in the lunar crust