Chemical sedimentary rock a large sustained eraptive eames chemically immature b. a potential cause of lahars c. major eruption, pyroclasties, hot gases d. hot fragments, cooled as explonively ejected. 3. e foliation 4. gas venting immature sedimentary rock mature sedimentary rock e can be organic, inorganic, or may be both 6, 7.nuee ardante 8. plinian 9. 10. regional metamorphism f. angular, variable size grains, poor sorting g. occurs over 100s to 1000s of km h. rounded, similar grain size, well-sorted l. grains aligned in direction of least stress j. grains include lots of feldspars, igneous rock pyroclastics fragments.