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Puerto Rico geologic map units in Bayamón quadrangle

af Artificial fill(Holocene)
Qa Alluvium(Quaternary)
Qb Beach Deposits(Quaternary)
Ql Landslide Deposits(Holocene-Pleistocene ?)
Qs Swamp Deposits(Holocene-Pleistocene ?)
QTs Blanket Sand Deposits(Quaternary ? late Tertiary ?)
Ta Aguada Limestone(lower Miocene)
Hard granular calcarenite overlain by alternating beds of chalky marl and rubbly limestone. Maximum estimated thickness, l50 m. Exposed from the San Juan quadrangle to the Aguadilla quadrangle and in the Utuado quadrangle
Tay Aymamon Limestone(lower Miocene)
Dense limestone and chalk. Maximum estimated thickness, 200 m. Exposed along the north coast of Puerto Rico from the Vega Alta quadrangle to the Aguadilla quadrangle
Tcb Cibao Formation(lower Miocene-upper Oligocene)
Calcareous clay, marl, and chalky limestone.
Tcbq Quebrada Arenas Member(Tertiary)
Dense limestone alternating with chalky limestone.
Tcbr Río Indio Limestone Member(Tertiary)
Limestone lenses of marly clay or beds of chalky limestone, grades into Mucarbones Sand laterally
TKh Hornblende quartz-diorite porphyry(Eocene)
Porphyritic hornblende quartz diorite, minor hornblende-granodiorite, quartz monzonite, and quartz diorite; locally pyritized, molybdenite-bearing, and/or includes disseminated chalcopyrite in the groundmass. Exposed in the San Sebastian, Bayaney, Monte Guilarte, Adjuntas, Cayey, Coamo, Maricao, Ponce, and Corozal quadrangles
Tmu Mucarbones Sand(lower Miocene ? upper Oligocene)
Quartz sand, interbedded with glauconitic, calcareous sand and thin-bedded calcareous clay. Maximum known thickness, l20 m. Exposed in the Corozal, Ciales, Naranjito, Bayamon, and San Juan quadrangles
Trp Río Piedras Siltstone(upper Paleocene)
Volcanic sandstone, siltstone, and basal conglomerate. Maximum thickness, l,400 m. Exposed in the Aguas Buenas, Naranjito and San Juan quadrangles
Ts San Sebastian Formation(middle ?-upper Oligocene)
Shaley clay, sandstone, and conglomerate. Estimated maximum thickness, l00 m. in outcrop, about 328 m. in the subsurface. Exposed in the San Sebastian, Moca, Central La Plata, Bayaney, Utuado, Florida, Ciales, Corozal, Naranjito, Bayamon, and San Juan quadrangles