During a period of 82 years (1931-2013), 39 genetic terms were introduced for various deposits. Of the 39 terms, only ten are meaningful in understandin8 the true depositional origin (e.9., turbidites), the remain...During a period of 82 years (1931-2013), 39 genetic terms were introduced for various deposits. Of the 39 terms, only ten are meaningful in understandin8 the true depositional origin (e.9., turbidites), the remaining 29 are just jargons (e.g., seismites, tsunamites, etc.). The genetic term "seismites", introduced by Seitacher (1969) for recognizing pa[aeoearthquakes in the sedimentary record, is a misnomer. The term was introduced in haste, based on an examination of a single exposure of the Miocene Monterey Formation (10 m) in California, without a rigorous scientific analysis. The fundamental problem is that earthquake is a triggering mechanism, not a depositional process. Type of triggers cannot be recognized in the ancient sedimentary record because evidence for triggers is not preserved by nature. Soft-sediment deformation structures (SSDS), commonly used as the criteria for interpreting seismites, are a product of liquefaction. However, liquefaction can be induced by any one of 21 triggers, which include earthquakes, meteorite impacts, tsunamis, sediment loading, among others. Brecciated ciasts, typically associated with earthquake-induced deposits in the Dead Sea Basin, are also common depositional products of debris flows (i.e., synsedimentary product unrelated to earthquakes). Also, various types of SSDS, such as duplex-like structures and ctastic injections, can be explained by synsedimentary processes unrelated to earthquakes. Case studies of sandstone petroleum res- ervoirs worldwide, which include Gulf of Mexico, North Sea, Norwegian Sea, Nigeria, Equatorial Guinea, Gabon, and Bay of Bengal, reveal that there is compelling empirical evidence for sediment loading being the primary cause of SSDS. The Krishna-Godavari Basin, located on the eastern continental margin of India, is ideal for sediment failures by multiple triggering mechanisms where overpressure and liquefaction have ted to multi-origin SSDS. Because tsunamis and meteorite impacts are important phenomena in d展开更多
文摘During a period of 82 years (1931-2013), 39 genetic terms were introduced for various deposits. Of the 39 terms, only ten are meaningful in understandin8 the true depositional origin (e.9., turbidites), the remaining 29 are just jargons (e.g., seismites, tsunamites, etc.). The genetic term "seismites", introduced by Seitacher (1969) for recognizing pa[aeoearthquakes in the sedimentary record, is a misnomer. The term was introduced in haste, based on an examination of a single exposure of the Miocene Monterey Formation (10 m) in California, without a rigorous scientific analysis. The fundamental problem is that earthquake is a triggering mechanism, not a depositional process. Type of triggers cannot be recognized in the ancient sedimentary record because evidence for triggers is not preserved by nature. Soft-sediment deformation structures (SSDS), commonly used as the criteria for interpreting seismites, are a product of liquefaction. However, liquefaction can be induced by any one of 21 triggers, which include earthquakes, meteorite impacts, tsunamis, sediment loading, among others. Brecciated ciasts, typically associated with earthquake-induced deposits in the Dead Sea Basin, are also common depositional products of debris flows (i.e., synsedimentary product unrelated to earthquakes). Also, various types of SSDS, such as duplex-like structures and ctastic injections, can be explained by synsedimentary processes unrelated to earthquakes. Case studies of sandstone petroleum res- ervoirs worldwide, which include Gulf of Mexico, North Sea, Norwegian Sea, Nigeria, Equatorial Guinea, Gabon, and Bay of Bengal, reveal that there is compelling empirical evidence for sediment loading being the primary cause of SSDS. The Krishna-Godavari Basin, located on the eastern continental margin of India, is ideal for sediment failures by multiple triggering mechanisms where overpressure and liquefaction have ted to multi-origin SSDS. Because tsunamis and meteorite impacts are important phenomena in d