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Maunga Whau (Mt Eden) is one of about 50 volcanos in the Auckland volcanic field. This data set gives topographic information for Maunga Whau on a 10 m by 10 m grid. A matrix with 87 rows and 61 columns, rows corresponding to grid lines running east to west and columns to grid lines running south to north.

Perspective view - volcano

Available layers:

- volcano_maungawhau.asc — the 10 m DEM digitized from the topo map;

Grid definition:

ncols: 61
nrows: 87
xllcorner: 2667400
yllcorner: 6478700
cellsize: 10 m

proj4:+init=epsg:27200

Lineage:

Digitized from a topographic map by Ross Ihaka. These data should not be regarded as accurate.

\> data(volcano)
>library(spatstat)
>LLC <- data.frame(E=174.761345, N=-36.879784)
>coordinates(LLC) <- ~E+N
>proj4string(LLC) <- CRS("+proj=longlat +datum=WGS84")
>LLC.NZGD49 <- spTransform(LLC, CRS("+init=epsg:27200"))
>volcano.r <- as.im(list(x=seq(from=2667405, length.out=61, by=10),
+     y=seq(from=6478705, length.out=87, by=10), 
+     z=t(volcano)\[61:1,\]))
>volcano.sp <- as(volcano.r, "SpatialGridDataFrame")
>proj4string(volcano.sp) <- CRS("+init=epsg:27200")
# str(volcano.sp)
# spplot(volcano.sp, at=seq(min(volcano.sp$v), max(volcano.sp$v),5),
+    col.regions=topo.colors(45))
>write.asciigrid(volcano.sp, "volcano\_maungawhau.asc", na.value=-1)

Data owner: LINZ
Location:Volcano Maungawhau, Auckland, New Zealand
36° 50’ 50.586” S,174° 45’ 56.646” E
See map: Google Maps

Attachment:
volcano_maungawhau.zip

Short title: landform

Inputs: Digital Elevation Model, classification parameters.
Outputs: Map showing landform classes according to Pennock and Corre (2001).

Purpose and use:

Landform Classification based on method of Pennock and Corre (2001). Classify landform units based on relief parameters provided using the topo.aml. Original Source are papers by Pennock et al., Rewritten in aml as closely as possible. Requirements: topo.aml, killgrids.aml, logoff.aml

Programming environment: Arc AML
Status of work: Public Domain
Reference: Geomorphometry: Concepts, Software, Applications

Short title: DEMsim

Inputs: control.txt - 1020 precise measurements (photogrametric + spot heights); elevations.txt - 2051 points (contours + spot heights); dem10m_tin.asc - 100x150 pixels 30m DEM.
Outputs: simulated DEMs, simulated error surfaces, error assessment statistics.

Purpose and use:

Script to generate and simulate DEMs and assess the error of the height measurements. Prepared for the needs of a research paper ‘Geostatistical modelling of topography using auxiliary maps’. Please consider testing the script before you use it with large datasets.

Programming environment: R / S language
Status of work: Public Domain
Reference: {Geostatistical modelling of topography using auxiliary maps}
Data set name: Zlatibor

Attachment:

zlatibor-1.zip

Short title: g_landf

Inputs: %1 - table with central values has to have same domain as the class map, %2 standard fuzziness factor (1.5), %3 - domain, %4 - SLOPE, %5 - PLANC and %6 - ACV.
Outputs: membership values (0-1) to each generic landform (stream, ridge, slope, plain, pit and peak)

Purpose and use:

Extracts six generic landforms (stream, ridge, slope, plain, pit and peak).

Programming environment: ILWIS
Status of work: Public Domain
Reference: Geomorphometry: Concepts, Software, Applications

g_landforms.zip

Ebergötzen is 10x10 km study area in the vicinity of the city of Göttingen in Central Germany (51°30’03.16’’–51°35’31.45’‘N; 10°00’28.67’’–10°09’15.21’‘E). This area has been extensively surveyed over the years, mainly for the purposes of developing operational digital soil mapping techniques. The dataset has also been frequently used by the SAGA development team and the SciLands GmbH in many of their demonstrations and documents.

Courtesy of Gehrt Ernst, the State Authority for Mining, Energy and Geology, Hannover, Germany.

The final Google Earth layout showing predicted soil texture fractions in topsoil.

Available layers:

- points.dbf - the point dataset consists of lab measurements four variables are available: SAND, SILT and CLAY (all expressed as % of mass measured for the 0-30 cm layer of soil) and SOILTYPE (type of soil based on the German classification system).
- DEM25.asc - 25 m DEM derived from the topo-maps;
- DEM100.asc - 100 m SRTMDEM;
- landimg.lan - LANDSAT image bands obtained from the http://image2000.jrc.it Corine Land Cover 2000 Project. The image consists of seven bands.
- ZONES.asc - 1:50.000 geological map of Germany.

Grid definition:

ncols: 400
nrows: 400
xllcorner: 3570000
yllcorner: 5708000
cellsize: 25 mproj4:+init=epsg:31467

Lineage: All input raster maps are in ArcInfo *.asc format, and the point data (tables) are in a *.dbf format. All coordinates are in the official German coordinate system, zone 3 (germany3): Transverse Mercator Projection, central meridian is 9°, false easting 3500000, Bessel 1841 ellipsoid with Potsdam datum. The bounding coordinates of the study area are: XMIN=3570000, YMIN=5708000, XMAX=3580000, YMAX=5718000. The input raster maps are available in two grid resolutions: 25 m (fine) and 100 m (coarse). The sand, silt and clay values have been determined by using the so-called_texture by hand_method: a surveyor distinguishes to which of the 32 texture classes a soil samples belongs to, and then estimates the content of fractions. E.g. texture classSt2has 10% clay, 25% silt and 65% sand.

Data owner: State Authority for Mining, Energy and Geology, Hannover, Germany
Reference: Gehrt, E., Buhner, J., (2001) Vom punkt zur flache — probleme des ‘upscaling’ in der bodenkartierung. In: Diskussionsforum Bodenwissenschaften: Vom Bohrstock zum Bildschirm. FH, Osnabruck, pp. 17-34.

Location:Ebergotzen, Germany
51° 34’ 19.2324” N,10° 6’ 28.7964” E
See map:Google Maps

Attachment:

ebergotzen.zip

ebergotzen_input.zip