GRAViMAG
========

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Web interface
-------------

**GRAViMAG**\ :math:`^2` is a web-based application for the processing
and interpretation of potential data:

-  gravity
-  magnetic
-  self-potential data.

The **GRAViMAG**\ :math:`^2` software is opened in a web browser. Simply
point the browser to the relevant url. Then, a **start screen** should
be shown:

.. figure:: images/GRAViMAG01.png
   :alt: *GRAViMAG start screen*

   *GRAViMAG start screen*

From this start screen, you can access:

-  open **old** projects
-  create **new** projects

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Create new project
------------------

we start creating a new project. Under ``Choose project``, we use
``new`` to create a new project. Fill in the form, search the location
in the map, and save the new project.

.. figure:: images/GRAViMAG02.png
   :alt: *GRAViMAG New project*

   *GRAViMAG New project*

The newly created project is opened and the location displayed.

.. figure:: images/GRAViMAG03.png
   :alt: *GRAViMAG Existing project*

   *GRAViMAG Existing project*

An existing project information can be edited later …

Once the project has been created, we start adding **gravity** and
**magnetic** data sets.

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Gravity data set
----------------

Under ``Gravity data``, we choose ``new`` to create a new gravity data
set. We need to label the new data set, then it appears in the dropdown
list below. We load this newly created data set.

**Note:** If the data set has been processed, its data trace is shown in
the map view window.

.. figure:: images/GRAViMAG04.png
   :alt: *GRAViMAG Existing project*

   *GRAViMAG Existing project*

Below the label, several tabs have appeared, which we need to manage the
data set:

-  **General**
-  **Base**
-  **Data**
-  **Raw**
-  **Process**
-  **View**
-  **Tides**
-  **Export**

General
~~~~~~~

This tab holds general information about the data set. Besdies an info
string ``INFO``, and the names of the operators ``OPERATOR``, the start
time ``TIME`` of the data set is given, an offset time relate to GMT
time ``OFFSET``, the instrument used ``INSTRUMENT``, a reference density
``RHO``, and the use of an earht tide file ``TIDES``.

The tide file needs to be uploaded first, and is the output of the
program ``eterna34``\ …

.. figure:: images/GRAViMAG04a.png
   :alt: *GRAViMAG General tab*

   *GRAViMAG General tab*

Base
~~~~

This tab holds information about the base point.

Here, coordinates, and possibly a known absolute gravity value [mGal],
are stored ``BASE1``. If no absolute gravity value is known, the value
``-1`` indicates that absolute gravity is calculated grom the geoid.

Then the repeted measurements of the base points are listed ``DRIFT1``.

.. figure:: images/GRAViMAG04b.png
   :alt: *GRAViMAG Base tab*

   *GRAViMAG Base tab*

Data
~~~~

This tab holds information about the data points.

Here, we can upload the file exported from the **CG-6 gravimeter**. To
accomplish this, we first iuse ``Delete all data`` to clear the table,
then use ``Import (CG-6 format)`` to import the gravity data.

If we have already processed the **accurate coordinates and
elevations**, we can swap them with the reading from the gravimeter,
using ``Replace coordinates``.

.. figure:: images/GRAViMAG04c.png
   :alt: *GRAViMAG Data tab*

   *GRAViMAG Data tab*

.. figure:: images/GRAViMAG04d.png
   :alt: *GRAViMAG Data tab*

   *GRAViMAG Data tab*

Raw
~~~

This tab lists the information from the input tabs in an **ascii
format**, usable for external processing…

Process
~~~~~~~

This tab is used to **process** the information entered. If the input
tabs has been entered correctly, a log file will be shown …

.. figure:: images/GRAViMAG04e.png
   :alt: *GRAViMAG Process tab*

   *GRAViMAG Process tab*

View
~~~~

In this tab, the processed **Bouguer anomaly** can be visualised as a
line plot.

.. figure:: images/GRAViMAG04f.png
   :alt: *GRAViMAG View tab*

   *GRAViMAG View tab*

Tides
~~~~~

In this tab, the loaded **Earth tides** can be visualised as a line
plot.

.. figure:: images/GRAViMAG04g.png
   :alt: *GRAViMAG Tides tab*

   *GRAViMAG Tides tab*

Export
~~~~~~

In this tab, the processed Bouguer gravity data can be exported into the
**geodyn** format.

.. figure:: images/GRAViMAG04h.png
   :alt: *GRAViMAG Export tab*

   *GRAViMAG Export tab*

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Magnetic data set
-----------------

Under ``Magnetics data``, we choose ``new`` to create a new magnetics
data set. We need to label the new data set, then it appears in the
dropdown list below. We load this newly created data set.

**Note:** If the data set has been processed, its data trace is shown in
the map view window.

.. figure:: images/GRAViMAG05.png
   :alt: *GRAViMAG Existing project*

   *GRAViMAG Existing project*

Below the label, several tabs have appeared, which we need to manage the
data set:

-  **General**
-  **Data**
-  **Raw**
-  **Process**
-  **View**
-  **Daily**
-  **Export**

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