coal measures /ˈkəʊl ˌmeʒəz/ rocas carboníferas: The rich organic matter deposited is the origin of the numerous coal measures.

carboniferous /ˌkɑːbəˈnɪfərəs/ carbonífera: fern-like fronds found in carboniferous rocks

granitic /grænˈɪtɪk, grəˈnɪt-/ granítica: Granitic rocks melt at about 650-700 degrees Celsius.

igneous /ˈɪgniəs/ ígnea: We crossed an expanse of igneous rock, red, potholed and uneven.

sedimentary /ˌsedɪˈmentəri/ sedimentaria: Mining corporations are interested in probing beneath the sedimentary rocks to find new deposits.

metamorphic /ˌmetəˈmɔːfɪk/ metamórfica: Last spring, the team discovered more metamorphic rocks along a different stretch of the Red River fault.

calcareous /kælˈkeəriəs/ calcárea: a layer of calcareous rock

porous /ˈpɔːrəs/ porosa: The bizarre, dreamlike landscape was formed by soft, porous rock from volcanic activity and eroded by the elements.

volcanic /vɒlˈkænɪk/ volcánica: The Romans constructed the temple mainly from local volcanic rock that they then faced with marble.