Resumen de Lake-Basin Type, Source Potential, and Hydrocarbon Character: An Integrated Sequence Stratigraphic–Geochemical Framework
Kevin M. Bohacs, Alan R. Carroll, John E. Neal, J. Mankiewicz Boczek
Rocks associated with lakes probably account for more than 20% of current worldwide hydrocarbon production (Kulke, 1995;Calhoun, 1999),and lacustrine organic-rich rocks are significant sources of these hydrocarbons. Lacus-trine sources and reservoirs are important in many areas of current and future exploration opportunities: Africa, South America, southeast Asia, China ( Hedberg, 1968;Powell, 1986;Smith, 1990;Katz, 1995).
The years since the last AAPG lake Memoir (Katz,1990) have seen both an expansion of work on modern and ancient lake systems and a focusing on their hydrocarbon potential. Through the efforts of individual workers and teams in academia and industry, along with collaborative efforts (e.g. ,IGCP-GLOPALS, International Association of Limnogeology),we have significantly increased our knowledge of lake systems on two fronts: key processes and sedimentary response-record(e.g., Anadon et al., 1991;Gierlowski-Kordesch and Kelts,1994; Katz, 1995).
Particularly enlightening have been the increase in (1)basin-scale studies of ancient systems that integrate stratigraphy, sedimentology, biofacies, and inorganic and organic geochemistry, (2) the use of reflection seismic data to gain large-scale 3-D perspectives on basin-fill history, (3) studies by petroleum-industry scientists that benefit from this large-scale perspective and physical, chemical, and biological processes and responses, and (4) studies of modern lakes and closely associated Quaternary deposits focused on key elements of sediment delivery and dispersal, organic production and preservation, and temporal evolution of lake hydrology (again aided by seismic-scale perspective, especially in east Africa) (e.g., Johnson et al., 1987;Scholz, 1995). Analytical advances and a broader experience base integrated into geological context have also contributed; geochemists have better tools for difficultnonmarine organic-matter mixtures
