Provenance (geology) Provenance (geology) Provenance in geology, is the reconstruction of the origin of sediments. The Earth is a dynamic planet, and all rocks are subject to transition between the three main rock types: sedimentary, metamorphic, and igneous rocks (the rock cycle). Rocks exposed to the surface are sooner or later broken down into sediments. Sediments are expected to be able to provide evidence of the erosion history of their parent source rocks. The purpose of provenance study is to restore the tectonic, paleo-geographic and paleo-climatic history. In the modern geological lexicon, "sediment provenance" specifically refers to the application of compositional analyses
Issues relating to biofuels Issues relating to biofuels There are various social, economic, environmental and technical issues with biofuel production and use, which have been discussed in the popular media and scientific journals. These include: the effect of moderating oil prices, the "food vs fuel" debate, poverty reduction potential, carbon emissions levels, sustainable biofuel production, deforestation and soil erosion, loss of biodiversity, effect on water resources, the possible modifications necessary to run the engine on biofuel, as well as energy balance and efficiency. The International Resource Panel, which provides independent scientific assessments and expert advice on a variety of resource-related themes, assessed the issues