def plot_mag_map_basemap(fignum, element, lons, lats, element_type, cmap='RdYlBu', lon_0=0, date=""):
    """
    makes a color contour map of geomagnetic field element

    Parameters
    ____________
    fignum : matplotlib figure number
    element : field element array from pmag.do_mag_map for plotting
    lons : longitude array from pmag.do_mag_map for plotting
    lats : latitude array from pmag.do_mag_map for plotting
    element_type : [B,Br,I,D] geomagnetic element type
        B : field intensity
        Br : radial field intensity
        I : inclinations
        D : declinations
    Optional
    _________
        cmap : matplotlib color map
        lon_0 : central longitude of the Hammer projection
        date : date used for field evaluation,
               if custom ghfile was used, supply filename


    Effects
    ______________
    plots a Hammer projection color contour with  the desired field element
    """
    if not has_basemap:
        print('-W- Basemap must be installed to run plot_mag_map_basemap')
        return
    from matplotlib import cm  # matplotlib's color map module
    lincr = 1
    if type(date) != str:
        date = str(date)
    fig = plt.figure(fignum)
    m = Basemap(projection='hammer', lon_0=lon_0)
    x, y = m(*meshgrid(lons, lats))
    m.drawcoastlines()
    if element_type == 'B':
        levmax = element.max()+lincr
        levmin = round(element.min()-lincr)
        levels = np.arange(levmin, levmax, lincr)
        cs = m.contourf(x, y, element, levels=levels, cmap=cmap)
        plt.title('Field strength ($\mu$T): '+date)
    if element_type == 'Br':
        levmax = element.max()+lincr
        levmin = round(element.min()-lincr)
        cs = m.contourf(x, y, element, levels=np.arange(
            levmin, levmax, lincr), cmap=cmap)
        plt.title('Radial field strength ($\mu$T): '+date)
    if element_type == 'I':
        levmax = element.max()+lincr
        levmin = round(element.min()-lincr)
        cs = m.contourf(
            x, y, element, levels=np.arange(-90, 100, 20), cmap=cmap)
        m.contour(x, y, element, levels=np.arange(-80, 90, 10), colors='black')
        plt.title('Field inclination: '+date)
    if element_type == 'D':
        # cs=m.contourf(x,y,element,levels=np.arange(-180,180,10),cmap=cmap)
        cs = m.contourf(
            x, y, element, levels=np.arange(-180, 180, 10), cmap=cmap)
        m.contour(x, y, element, levels=np.arange(-180, 180, 10), colors='black')
        plt.title('Field declination: '+date)
    cbar = m.colorbar(cs, location='bottom')