Graphics Programs Reference
In-Depth Information
4.
Signal processing
- This includes all techniques for manipulating a signal
to minimize the effects of noise, to correct all kinds of unwanted distor-
tions or to separate various components of interest. It includes the design,
realization and application of fi lters to the data. These methods are widely
used in combination with time-series analysis, e.g., to increase the signal-
to-noise ratio in climate time series, digital images or geophysical data.
5.
Spatial analysis
- The analysis of parameters in 2D or 3D space. Therefore,
two or three of the required parameters are coordinate numbers. These
methods include descriptive tools to investigate the spatial pattern of geo-
graphically distributed data. Other techniques involve spatial regression
analysis to detect spatial trends. Finally, 2D and 3D interpolation tech-
niques help to estimate surfaces representing the predicted continuous
distribution of the variable throughout the area. Examples are drainage-
system analysis, the identifi cation of old landscape forms and lineament
analysis in tectonically-active regions.
6.
Image processing
- The processing and analysis of images has become
increasingly important in earth sciences. These methods include manipu-
lating images to increase the signal-to-noise ratio and to extract certain
components of the image. Examples for this analysis are analyzing satel-
lite images, the identifi cation of objects in thin sections and counting an-
nual layers in laminated sediments.
7.
Multivariate analysis
- These methods involve observation and analysis
of more than one statistical variable at a time. Since the graphical repre-
sentation of multidimensional data sets is diffi cult, most methods include
dimension reduction. Multivariate methods are widely used on geochem-
ical data, for instance in tephrochronology, where volcanic ash layers are
correlated by geochemical fi ngerprinting of glass shards. Another impor-
tant example is the comparison of species assemblages in ocean sedi-
ments in order to reconstruct paleoenvironments.
8.
Analysis of directional data
- Methods to analyze circular and spherical
data are widely used in earth sciences. Structural geologists measure
and analyze the orientation of slickenlines (or striae) on a fault plane.
Circular statistics is also common in paleomagnetics applications.
Microstructural investigations include the analysis of the grain shape
and quartz c-axis orientation in thin sections. The methods designed to
deal with directional data are beyond the scope of the topic. There are
