Holocene Evolution, OFR 01-076

APPENDIX – ARCVIEW CALCULATIONS

Individual surface generation:

The calculations for the individual surface generations assume that the ravinement and lowstand surfaces have been clipped with the appropriate portions of the polygons corresponding the a particular time frame.  The italicized grid names are suggested grid name, but may be changed depending on an individual's naming convention.

11 thousand years ago

Shelf

((-60.0.AsGrid - [rav11ty]) < ([rav2pres] * 0.2143)).Con(-60.0.AsGrid, [rav11ty] + ([rav2pres]*0.2143))

Bay

( [Low11ty] > -60.0.AsGrid).con([Low11ty],-60.0.AsGrid)

 10 thousand years ago

Shelf

((-47.0.AsGrid - [rav10ty]) < ([rav2pres] * 0.2857)).Con(-47.0.AsGrid, [rav10ty] + ([rav2pres]*0.2857))

Bay

( [Low10ty] > -47.0.AsGrid).con([Low10ty],-47.0.AsGrid)

9 thousand years ago

Shelf

((-32.0.AsGrid - [rav9ty]) < ([rav2pres] * 0.3571)).Con(-32.0.AsGrid, [rav9ty] + ([rav2pres]*0.3571))

Bay

( [Low9ty] > -32.0.AsGrid).con([Low9ty],-32.0.AsGrid)

8 thousand years ago

Shelf

((-20.0.AsGrid - [rav8ty]) < ([rav2pres] * 0.4286)).Con(-20.0.AsGrid, [rav8ty] + ([rav2pres]*0.4286))

Bay

( [Low8ty] > -20.0.AsGrid).con([Low8ty],-20.0.AsGrid)

7 thousand years ago

Shelf

((-15.0.AsGrid - [rav7ty]) < ([rav2pres] * 0.5000)).Con(-15.0.AsGrid, [rav7ty] + ([rav2pres]*0.5000))

Bay

( [Low7ty] > -15.0.AsGrid).con([Low7ty],-15.0.AsGrid)

6 thousand years ago

 Shelf

((-11.0.AsGrid - [rav6ty]) < ([rav2pres] * 0.5714)).Con(-11.0.AsGrid, [rav6ty] + ([rav2pres]*0.5714))

Bay

( [Low6ty] > -11.0.AsGrid).con([Low6ty],-11.0.AsGrid)

5 thousand years ago

Shelf

((-8.0.AsGrid - [rav5ty]) < ([rav2pres] * 0.6429)).Con(-8.0.AsGrid, [rav5ty] + ([rav2pres]*0.6429))

Bay

( [Low5ty] > -8.0.AsGrid).Con([Low5ty],(-8.0.AsGrid < [present]).Con(-8.0.AsGrid, [present]))

Beach

[Beach5ty] + [rav2pres]

 4 thousand years ago

Shelf

((-5.5.AsGrid - [rav4ty]) < ([rav2pres] * 0.7143)).Con(-5.5.AsGrid, [rav4ty] + ([rav2pres]*0.7143))

Bay

( [Low4ty] > -5.5.AsGrid).Con([Low4ty],(-5.5.AsGrid < [present]).Con(-5.5.AsGrid, [present]))

Beach

[Beach4ty] + [rav2pres]

3 thousand years ago

Shelf

((-3.0.AsGrid - [rav3ty]) < ([rav2pres] * 0.7857)).Con(-3.0.AsGrid, [rav3ty] + ([rav2pres]*0.7857))

Bay

( [Low3ty] > -3.0.AsGrid).Con([Low3ty],(-3.0.AsGrid < [present]).Con(-3.0.AsGrid, [present]))

Beach

[Beach3ty] + [rav2pres]

2 thousand years ago

Shelf

((-1.5.AsGrid - [rav2ty]) < ([rav2pres] * 0.8571)).Con(-1.5.AsGrid, [rav2ty] + ([rav2pres]*0.8571))

Bay

( [Low2ty] > -1.5.AsGrid).Con([Low2ty],(-1.5.AsGrid < [present]).Con(-1.5.AsGrid, [present]))

Beach

[Beach2ty] + [rav2pres]

 1 thousand years ago

Shelf

((-0.5.AsGrid - [rav1ty]) < ([rav2pres] * 0.9286)).Con(-0.5.AsGrid, [rav1ty] + ([rav2pres]*0.9286))

Bay

( [Low1ty] > -0.5.AsGrid).Con([Low1ty],(-0.5.AsGrid < [present]).Con(-0.5.AsGrid, [present]))

Beach

[Beach1ty] + [rav2pres] 

Filter

Low-Pass filter applied to all surfaces to remove the NODATA values within the study area where "Agrid" is the grid being filtered

[AGrid].Filter(#GRID_FILTERTYPE_LOW,FALSE)

Surface Shift

These values reflect the amount each surface will be shifted so that that the same color legend can be used with all surfaces and the zero value represents that time periods shoreline. Where the depth to the sea level curve is an integer, that value is used as the shifting value. Where the depth to the sea level curve is a floating point value, that value is adjusted by 0.1 due to ArcView’s poor handing of legends on floating point grids.

[surf11tyclip] + 60

[surf10tyclip] + 47

[surf9tyclip] + 32

[surf8tyclip] + 20

[surf7tyclip] + 15

[surf6tyclip] + 11

[surf5tyclip] + 8

[surf4tyclip] + 5.4

[surf3tyclip] + 2.9

[surf2tyclip] + 1.4

[surf1tyclip] + 0.4

The following equations are the equations used to shift the 1000 yr BP surfaces as well as the modern day DEM. Where the study area shifted surface exists, those grid values are used. Outside that clipped surface, the shifted present day DEM values are used. The exception to this is the Columbia River outside the study area. In all cases, the present day bathymetery for the Columbia River is used for aesthetic purposes.

"Colriver" is the present day bathymetry of the Columbia River outside the study area.

"Cranddem" is the present day DEM and Columbia River.

"Surf*clip" refers to the filtered surface at a particular time interval, clipped to the study area bounding polygon.  These grids are contained on the CD-ROM.

(([Colriver] .IsNull).Con((( ([Surf11tyclip]+60).IsNull).Con(([Cranddem]+60),([Surf11tyclip]+60))),[Colriver]))

(([Colriver] .IsNull).Con((( ([Surf10tyclip]+47).IsNull).Con(([Cranddem]+47),([Surf10tyclip]+47))),[Colriver]))

(([Colriver] .IsNull).Con((( ([Surf09tyclip]+32).IsNull).Con(([Cranddem]+32),([Surf09tyclip]+32))),[Colriver]))

(([Colriver] .IsNull).Con((( ([Surf08tyclip]+20).IsNull).Con(([Cranddem]+20),([Surf08tyclip]+20))),[Colriver]))

(([Colriver] .IsNull).Con((( ([Surf07tyclip]+15).IsNull).Con(([Cranddem]+15),([Surf07tyclip]+15))),[Colriver]))

(([Colriver] .IsNull).Con((( ([Surf06tyclip]+11).IsNull).Con(([Cranddem]+11),([Surf06tyclip]+11))),[Colriver]))

(([Colriver] .IsNull).Con((( ([Surf05tyclip]+8).IsNull).Con(([Cranddem]+8),([Surf05tyclip]+8))),[Colriver]))

(([Colriver] .IsNull).Con((( ([Surf04tyclip]+5.4).IsNull).Con(([Cranddem]+5.4),([Surf04tyclip]+5.4))),[Colriver]))

(([Colriver] .IsNull).Con((( ([Surf03tyclip]+2.9).IsNull).Con(([Cranddem]+2.9),([Surf03tyclip]+2.9))),[Colriver]))

(([Colriver] .IsNull).Con((( ([Surf02tyclip]+1.4).IsNull).Con(([Cranddem]+1.4),([Surf02tyclip]+1.4))),[Colriver]))

(([Colriver] .IsNull).Con((( ([Surf01tyclip]+0.4).IsNull).Con(([Cranddem]+0.4),([Surf01tyclip]+0.4))),[Colriver]))

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