Basalt is one of the most common igneous rocks found. It is the major constituent of the upper layer of the ocean floors (usually as pillow lava), and hot spot volcanoes (such as Ring of Fire Area). Basalt commonly forms on the continents, usually the result of hot spot activity.
Breccia is a sawed slab of rock with fragments are composed of quartzite (metamorphosed quartz sandstone). Breccias with shape form are associated with mechanical weathering in regions of high tectonic activity. It often deposited in alluvial fans at the base of slopes.
Conglomerate is a sawed slab of rock with rounded gravel particles that has been wet with water before photographing mostly toward the upper size range of granules (4-64 mm). In context of the outcrop this rock was deposited subaqueously (below water) or in fan deltas. Conglomerates this immature are associated with regions of high tectonic activity, typically relatively close to the sourceland.
Diorit is an intermediate igneous rock from the middle of Bowen's Reaction Series. This specimen is low on the mafic side, but the next specimen runs high. Quartz is sometime present between 5% and 20%, but if quartz exceeds 20% the rock is called a grano diorite. Diorite is the result of fractional melting of a mafic parent rock above a subduction zone. It is commonly produced in volcanic arcs. It emplaces in large batholiths
Dolomite is fine grained rock with conchoidal fracture and weak laminations running parallel to bedding. The laminations are probably algal laminates. Commonly associated with regions of tectonic stability or shallow water environments associated with continental shelves or epeiric (epicontinental) sea.
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