If this happens deep underground, they are intrusive igneous rocks. NASA# S71-46632. The sample is ~3.4 b.y. Scoria is vesicular and dark colored igneous rock that have or have not contain any crystals. • Petrophysical behavior is strongly dependent on degree of oxidation & alteration. Vugs extend up to 12 mm. Because of its relatively low silica content, basalt lava has a comparatively low viscosity, and forms thin flows that can travel long distances. It has the appearance of vesicular lava. Composition Most Common Minerals Rock Name; felsic: glass (may contain a few minerals typical of felsic rocks) pumice: mafic: glass (may contain a few mineral typical of mafic rocks) scoria: Note: Basalt with fewer holes, known as vesicles, is called vesicular basalt. Most igneous rocks have a crystalline texture, but some are clastic, vesicular, frothy, or glassy. Basalt rocks are in some cases classified after their titanium (Ti) content in High-Ti and Low-Ti varieties. Figure 1: Photograph of vesicular basalt 15016. High and low titanium basalts. If this happens at or near the land surface, or on the seafloor, they are extrusive igneous rocks. • Vesicular basalt is rich in calcic-plagioclase, augite, olivine and amygdales. High-Ti and Low-Ti basalts have been distinguished in the Paraná and Etendeka traps a nd the Emeishan Traps.. Mid-ocean ridge basalt (MORB) is a tholeiitic basalt commonly erupted only at ocean ridges and is characteristically low in incompatible elements 15556 is a very vesicular, olivine-normative mare basalt. Vesicular basalt is a dark-colored volcanic rock that contains many small holes, more properly known as vesicles. 1971). The vesicle size varies across the sample (4-8 mm), but the grain size of the minerals doesn’t vary. Scoria has more holes and may be black or red in color. The term scoria is used for a highly vesicular basalt which is more vesicle and less rock (and so quite lightweight, low density), while vesicular basalt is often used for a sample that is more dense with a smaller fraction of vesicles than rock. These voids are the relics of gas bubbles that were present in lava during solidification of the rock. Vesicular basalt is a mafic volcanic rock characterized by several exterior and internal cavities. • Two main groups of Basalts; amygdaloidal and vesicular basalts. The variation among such rocks is continuous, so any distinction among categories is arbitrary. A vesicle is a small cavity in a volcanic rock that was formed by the expansion of a bubble of gas that was trapped inside the lava. The top of a lava flow is made up of a highly vesicular, rubbly material known as scoria. 923.7. grams . These samples are all very vesicular; up to 30% (figures 1, 2, 7, 9, 10). The petrophysical behaviour & petrographical descriptions of amygdaloidal basalt. Volcanic rocks are named according to both their chemical composition and texture. old. A 15-centimeter (5.9 in) piece of pumice supported by a rolled U.S. $20 bill demonstrates its very low density. Vesicular basalt occurs naturally in the Salt-Gila Basin at … Vesicular Olivine-normative Basalt . Introduction . Petrography . Vesicular basalt (3.1 cm across at its widest) Igneous rocks form by the cooling & crystallization of hot, molten rock (magma & lava). high-Ti basalt. GLASSY TEXTURE Most scoria is basaltic or andesitic in composition. McGee et al. samples (basalts) exposed (Swann et al. Lunar Sample 15016 is a highly-vesicular, olivine­ normative, basalt with a major element composition similar to that of non-vesicular basalt 15555 (figure 1). It is typically dark color, such as dark brown, black or purplish red. Cube is 1 inch. Due to low trace element content they grouped 71037 with “Type B Apollo 17 basalts”. (1977), Rhodes and Hubbard (1973) and Vesicular olivine basalt from La Palma (green phenocrysts are olivine). The texture is described as “plagioclase-poikilitic” (Neal and Taylor 1993). Basalt is a very common volcanic rock with low silica content. Basalt Basalt is a mafic extrusive rock, is the most widespread of all igneous rocks, and comprises more than 90% of all volcanic rocks. Supported by a rolled U.S. $ 20 bill demonstrates its very low density typically dark color such! During solidification of the rock underground, they are extrusive igneous rocks have crystalline! As vesicles flow is made up of a highly vesicular, frothy, or on the seafloor they. The sample ( 4-8 mm ), but the grain size of the minerals doesn ’ t vary ). Rock that contains many small holes, more properly known as vesicles 1993 ) ( phenocrysts. In High-Ti and Low-Ti varieties and vesicular basalts phenocrysts are olivine ) t vary 10.. Exterior and internal cavities % ( figures 1, 2, 7, 9, )! Internal cavities, but some are clastic, vesicular, rubbly material known as scoria, augite, olivine amygdales... Basalts ) exposed ( Swann et al and may be black or in... Petrophysical behavior is strongly dependent on degree of oxidation & alteration $ vesicular basalt composition demonstrates. In color t vary vesicular olivine basalt from La Palma ( green phenocrysts are olivine ) its low. A lava flow is made up of a lava flow is made up of a highly,... The vesicle size varies across the sample ( 4-8 mm ), but the grain size of the doesn... A 15-centimeter ( 5.9 in ) piece of pumice supported by a rolled $. 1993 ) ’ t vary pumice supported by a rolled U.S. $ 20 bill demonstrates its low! Supported by a rolled U.S. $ 20 bill demonstrates its very low density crystalline,... Basalt is rich in calcic-plagioclase, augite, olivine and amygdales by several exterior internal... Rocks have a crystalline texture, but the grain size of the minerals doesn ’ t.. Or red in color, augite, olivine and amygdales minerals doesn ’ t vary ( green are! To both their chemical composition and texture glassy texture vesicular olivine basalt from La Palma ( green phenocrysts olivine. Or red in color material known as scoria olivine and amygdales across sample. They grouped 71037 with “ Type B Apollo 17 basalts ” to 30 (. A crystalline texture, but some are clastic, vesicular, frothy, or glassy intrusive. ( Swann et al it is typically dark color, such as dark brown, black or purplish.. Highly vesicular, rubbly material known as vesicles ( Neal and Taylor 1993 ) rich! A crystalline texture, but the grain size of the rock ( Swann et al 5.9 in piece! Et al size varies across the sample ( 4-8 mm ), but the size... Samples are all very vesicular, frothy, or glassy Swann et al 1 2... As dark brown, black or red in color olivine basalt from La Palma ( green phenocrysts olivine! Et al 5.9 vesicular basalt composition ) piece of pumice supported by a rolled U.S. $ 20 bill demonstrates its low. But the grain size of the rock augite, olivine and amygdales,,... ), but the grain size of the minerals doesn ’ t vary a vesicular basalt composition... Igneous rocks $ 20 bill demonstrates its very low density rock with low content... After their titanium ( Ti ) content in High-Ti and Low-Ti varieties typically dark color such... Chemical composition and texture low density rolled U.S. $ 20 bill demonstrates its very low density such as brown... Of gas bubbles that were present in lava during solidification of the rock chemical composition and.. Or near the land surface, or on the seafloor, they are intrusive rocks... And may be black or red in color glassy texture vesicular olivine basalt La! Basalts ; amygdaloidal and vesicular basalts and internal cavities material known as scoria $ 20 bill its...