Abstract Mudstone breccias deposited by debris flows in the lacustrine Green River Formation of the Piceance Creek Basin, Colorado, may not represent random and unpredictable events as previously thought. Spectral analysis of mudstone breccia beds in the Wolfridge Minerals John Savage #24-1 basin center core reveals a record of short eccentricity (94.58 kyr), obliquity (50.78 kyr and 39.26 kyr), and precession (21.85 kyr and 18.56 kyr). Of particular interest to this investigation are the records of eccentricity and precession, together which indicate that insolation forcing of monsoons occurred every ~18–21 kyr, and that every ~94 kyr, insolation maxima exceeded a threshold of 528 W/m2, resulting in more significant monsoon amplification. Strengthened monsoon activity would have led to an increase in precipitation and runoff delivered to the lake. This increase in inflow resulted in lake-level rise which, in turn, decreased basin slope stability and triggered periodic sub-lacustrine debris flows that deposited the mudstone breccias.

中文翻译：

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湖底泥石流的日照强迫——季风强化是否起到了作用？始新世湖泊绿河组，Piceance Creek 盆地，科罗拉多州

摘要 泥岩角砾岩沉积在科罗拉多州 Piceance Creek 盆地湖相绿河组中的泥岩角砾岩可能并不像以前认为的那样代表随机和不可预测的事件。Wolfridge Minerals John Savage #24-1 盆地中心岩心泥岩角砾岩床的光谱分析揭示了短偏心率（94.58 kyr）、倾角（50.78 kyr 和 39.26 kyr）和岁差（21.85 kyr 和 18.56 kyr）的记录。这项调查特别有趣的是偏心率和岁差的记录，它们一起表明季风的日晒强迫每~18-21 kyr 发生一次，并且每~94 kyr 日照最大值超过528 W/m2 的阈值，导致更显着的季风放大作用。季风活动加强会导致降水和流入湖泊的径流增加。