- Volcanic breccia—Dacitic to andesitic lithic tuff breccia with lesser (crystal) lithic lapilli tuff and minor agglomerate; typically dark green-gray to light gray, but multicolored with red, green, and black to gray volcanic clasts and matrix common; weathers to gray-brown. Breccia beds are generally very thick, massive, and moderately to poorly sorted. Bomb breccias are common in the map area, with maximum clast size varying from 18 to 60 in. (45–180 cm) at significant sites 14P (sec. 19, T27N R8E), 18Q (sec. 22, T27N R8E), 21G (sec. 30, T27N R8E), 30L (sec. 35, T27N R7E), and 54M (sec. 32, T27N R8E), with the largest observed bomb at 31N (sec. 24, T27N R7E). Poorly sorted volcanic breccia interbedded with volcanic sediments (unit Evcp) at site 21G contains bombs up to 43 in. (110 cm), indicating catastrophic input of breccia into fluvial basins. Pumiceous lapilli tuff beds are generally mapped as tuff (unit Evtp). However, a few pumiceous tuff breccia beds are compositionally similar to pumiceous lapilli tuff beds and may be coarser-grained equivalents. Some breccia beds contain scattered dark-gray basaltic andesite to basalt clasts, and a few contain minor exotic greenstone, metasandstone, and metachert clasts derived from nonvolcanic sources (Danner, 1957). Unit Evbxp consists for the most part of very thick pyroclastic flow deposits containing homogeneous dacite fragments, likely resulting from volcanic dome collapse. Some breccia beds are thinner pyroclastic surge deposits in volcanic epiclastic rocks or flow breccia beds in flows. Thin to very thick interbeds of epiclastic volcanic sandstones in a few outcrops show that some very thick breccia units are the result of emplacement of stacked pyroclastic deposits into restricted fluvial basins. Unlike more distal volcanic Mount Persis unit environments, lahars are rare in the map area and included with unit Evbxp. Unit Evbxp clasts in nearby quadrangles are either (1) two-pyroxene andesites that are petrographically and geochemically similar to the Mount Persis unit andesite flows, or (2) semi-vesicular, light-green dacite clasts (63–70% SiO2)(Dragovich and others, 2009a,b, 2010a,b, 2011a,b, 2012). As in adjacent quadrangles, breccia clasts in the Sultan quadrangle appear to be mostly augite ± hornblende to plagioclase ± quartz phyric dacite (63–65% SiO2). Some dacitic breccia may correlate with the extensive hornblende-phyric dacite breccia unit (38.1 Ma) of Tabor and others (1993) to the east of the map area.