Notes: Following Johnson's approach taken in the GSA Special Paper 284, we have tried to formalize our thinking placing HALIP as an event in a system framework. This system diagram involves 2 axes. The vertical one represents time and portion of the classic rock cycle. The horizontal one is a line of reasoning linking a geologic outcome with a contributing cause. In particular a geologic event pertubates the system by changing some primary factors, such as relief. In turn, expert rules indicate how those changing factors modify the basic processes such as clay production by silicate hydrolysis, and thus modify the material at a a stage in the 'rock cycle'. This framework could actually be implemented as a computer model where a user specifies initial conditions, and events, and the output is sediment character. At this stage this is a useful way for us to explore multiple working hypotheses. As one example consider magmatic underplating and its possible stratigraphic effects as recently modeled by MacLennan and Lovell. A uplift subsidence cycle should effect relief, and detritus production and transport. Additionally diagenesis may be affected by a change in the local geothermal gradient.

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