Levels of U.S. aid to Pakistan have waxed and waned since the 1980s, according to American geo-political initiatives. Since 9/11, the country has received $19.34 billion in economic and military aid from the U.S. for its cooperation in the so-called âwar on terror.â.
There are three types of basalt lava flows: pillow, pahoehoe, and aa. Pillow Lava: Pillow lavas are volumetrically the most abundant type because they are erupted at mid-ocean ridges and because they make up the submarine portion of seamounts and large intraplate volcanoes, like the Hawaii-Emperor seamount chain.Pahoehoeâ and âaaâ are Hawaiian words that describe lava. Pahoehoe Lava: Pahoehoe is the second most abundant type of lava flow. Pahoehoe near the coast of Kilauea. Photo by Steve Mattox, 1989.
Two types of lava flows, pahoehoe and aa, are different textural forms of otherwise identical lava. The smooth-textured pahoehoe lavas (left) are formed by stable upwelling of gas-poor lava, whereas the hackly-surfaced aa flows are produced during eruptions with high lava fountaining of gas-rich magma.