The well known Cretaceous seaway in North America was recognized in the middle of the last century and the Palaeogene seaway in East China was proposed by the author recently. The two seaways located on the opposite s...The well known Cretaceous seaway in North America was recognized in the middle of the last century and the Palaeogene seaway in East China was proposed by the author recently. The two seaways located on the opposite sides of North Pacific Ocean may be not a coincidence, and a comparative study was made in this paper. The results show that the two seaways inundated basins share several similarities particularly in basin origin, filling processes and reservoir facies. It is suggested that reservoir facies of estuarine sandstone and shelf bar sandstone related to sea level fluctuation, which are well developed in the Cretaceous seaway covered basins in North America might have been also developed here in Palaeogene seaway inundated basins in East China. Therefore it is worth paying more attention to finding these new reservoir facies on this side of the Pacific ocean. Evidences of sedimentology and ichnology indicate that good prospects are likely.展开更多
The fuel consumption of a ship has always been an important research topic,but nowadays its importance has even increased as it is directly related to a ship’s greenhouse gas(GHG)emissions,which is now tightly regula...The fuel consumption of a ship has always been an important research topic,but nowadays its importance has even increased as it is directly related to a ship’s greenhouse gas(GHG)emissions,which is now tightly regulated.In this paper,such a dynamic model is presented.The ship’s resistance in calm water and propeller’s performance in open water are required as input.The hull efficiency is estimated empirically.The diesel engine is modelled by a first-order transfer function with a delayed response and its performance is calibrated with the data from the manufacturer’s catalogue.A governor is applied to maintain the pre-set engine’s rotational speed and to control the engine fuel rate.A slope limiter is employed to approximate the actual engine operation during engine transients.The default values can be obtained from the manufacturer engine load acceptance diagram.The developed model is implemented in MATLAB SIMULINK environment.After validation against third-party published results,the influence of using different types of governors on ship speed and fuel consumption is investigated.The model is also applied to simulate the fuel consumption of a ship during a typical acceleration manoeuvre and the scenario of a real ship encountering harsh weather conditions.展开更多
The Turonian Notom Delta is one of the Ferron fluvial-deltaic wedges deposited in the foreland basins of the Cretaceous Seaway of North America.The wedge is exposed three dimensionally in the Henry Mountains region Ut...The Turonian Notom Delta is one of the Ferron fluvial-deltaic wedges deposited in the foreland basins of the Cretaceous Seaway of North America.The wedge is exposed three dimensionally in the Henry Mountains region Utah,USA.High-resolution sequence stratigraphic analysis along a 35 km dip-oriented outcrop belt shows that the wedge consists of six depositional sequences.Ammonite and Inoceramid biostratigraphy and 40Ar/39Ar age dating of various bentonites show that the wedge was deposited from 91.25 Ma to 90.63 Ma,an interval of merely 0.62 Ma.Assuming each sequence is formed over a similar time span,each sequence,thus,represents about 105 yr,suggesting high-frequency depositional sequences.Amplitude of relative sea-level changes,built on shoreline trajectory,is 2-61 m,with an average of only 20 m.Fluvial incision during high-frequency and low-amplitude relative sealevel fall is mainly around the highstand prism.Incision diminishes rapidly up dip and down dip,and the resultant incised valleys are narrow and shallow.Such sea-level fluctuations also result in small,stratigraphically complex shoreline sandstones that need special attention during hydrocarbon exploration.展开更多
文摘The well known Cretaceous seaway in North America was recognized in the middle of the last century and the Palaeogene seaway in East China was proposed by the author recently. The two seaways located on the opposite sides of North Pacific Ocean may be not a coincidence, and a comparative study was made in this paper. The results show that the two seaways inundated basins share several similarities particularly in basin origin, filling processes and reservoir facies. It is suggested that reservoir facies of estuarine sandstone and shelf bar sandstone related to sea level fluctuation, which are well developed in the Cretaceous seaway covered basins in North America might have been also developed here in Palaeogene seaway inundated basins in East China. Therefore it is worth paying more attention to finding these new reservoir facies on this side of the Pacific ocean. Evidences of sedimentology and ichnology indicate that good prospects are likely.
文摘The fuel consumption of a ship has always been an important research topic,but nowadays its importance has even increased as it is directly related to a ship’s greenhouse gas(GHG)emissions,which is now tightly regulated.In this paper,such a dynamic model is presented.The ship’s resistance in calm water and propeller’s performance in open water are required as input.The hull efficiency is estimated empirically.The diesel engine is modelled by a first-order transfer function with a delayed response and its performance is calibrated with the data from the manufacturer’s catalogue.A governor is applied to maintain the pre-set engine’s rotational speed and to control the engine fuel rate.A slope limiter is employed to approximate the actual engine operation during engine transients.The default values can be obtained from the manufacturer engine load acceptance diagram.The developed model is implemented in MATLAB SIMULINK environment.After validation against third-party published results,the influence of using different types of governors on ship speed and fuel consumption is investigated.The model is also applied to simulate the fuel consumption of a ship during a typical acceleration manoeuvre and the scenario of a real ship encountering harsh weather conditions.
文摘The Turonian Notom Delta is one of the Ferron fluvial-deltaic wedges deposited in the foreland basins of the Cretaceous Seaway of North America.The wedge is exposed three dimensionally in the Henry Mountains region Utah,USA.High-resolution sequence stratigraphic analysis along a 35 km dip-oriented outcrop belt shows that the wedge consists of six depositional sequences.Ammonite and Inoceramid biostratigraphy and 40Ar/39Ar age dating of various bentonites show that the wedge was deposited from 91.25 Ma to 90.63 Ma,an interval of merely 0.62 Ma.Assuming each sequence is formed over a similar time span,each sequence,thus,represents about 105 yr,suggesting high-frequency depositional sequences.Amplitude of relative sea-level changes,built on shoreline trajectory,is 2-61 m,with an average of only 20 m.Fluvial incision during high-frequency and low-amplitude relative sealevel fall is mainly around the highstand prism.Incision diminishes rapidly up dip and down dip,and the resultant incised valleys are narrow and shallow.Such sea-level fluctuations also result in small,stratigraphically complex shoreline sandstones that need special attention during hydrocarbon exploration.