optional, single

—

Indicates the length in metres as a real number of the shorter side of an area (rectangle), for example examined through an archeological survey, or a biological mapping.

<sitedata>

—

<arealength>, <maximumdepth>, <minimumdepth>, <sitedata>

<sitedata>
    <-- the longer side of the examined area has a length of 3 m -->
    <arealength>3.0</arealength>

    <-- the shorter one has a width of 2 m -->
    <areawidth>2.0</areawidth>
</sitedata>