On the continents, gabbro can be found within thick lava flows of basaltic composition, where slow cooling allows large crystals to form. Gabbro will also be present in the deep plutons that form when magma chambers that feed basaltic eruptions crystallize.
Large volumes of gabbro are present beneath extensive flood basalts such as the Columbia River flood basalts of Washington and Oregon and the Deccan Traps of India.
