▁er upt ed ▁ 9 . 4 ▁my a ▁from ▁an ▁unknown ▁vent ▁and ▁has ▁a ▁volume ▁of ▁ ▁of ▁d ac ite . ▁While ▁the ▁vent ▁location ▁is ▁unknown , ▁the ▁composition ▁of ▁the ▁ign im br ite , ▁and ▁its ▁d ating ▁and ▁distribution , ▁indicate ▁an ▁association ▁with ▁this ▁group . ▁The ▁dom es ▁are ▁poor ly ▁research ed , ▁with ▁the ▁Cos cal ito ▁d ome ▁dated ▁ 8 . 9 – 8 . 7 ▁my a ▁and ▁Cer ro ▁A min cha ▁ 8 . 0 1 . ▁The ▁total ▁volume ▁of ▁this ▁group ▁is ▁, ▁indicating ▁a ▁flux ▁rate ▁of ▁. ▁ ▁The ▁G ordo ▁group , ▁which ▁er upt ed ▁ 6 – 4 ▁my a ▁following ▁a ▁probable ▁ 2 - mill ion - year ▁hi atus , ▁is ▁located ▁in ▁the ▁southern ▁and ▁western ▁parts ▁of ▁the ▁cluster . ▁Cer ro ▁G ordo ▁itself ▁( 5 . 4 9 ▁my a ) ▁has ▁a ▁cr ater ▁that ▁is ▁bre ached ▁west wards , ▁expos ing ▁about ▁twelve ▁radial ▁dy kes ▁but ▁with ▁no ▁trace ▁of ▁a ▁de br is ▁a val anche . ▁One ▁of ▁the ▁larger ▁cent res ▁of ▁the ▁cluster , ▁G ordo ▁is ▁associated ▁with ▁a ▁la va ▁field ▁on ▁its ▁western ▁side ▁that ▁is ▁dated ▁ 4 . 9 ▁my a . ▁Cer ro ▁Pu qu íos ▁and ▁Cer ro ▁Neg ro ▁( 5 . 8 1 – 5 . 2 8 ▁my a ) ▁lie ▁on ▁the ▁southern ▁side