\begin{table}%t5
\caption{\label{comp_goettel}Same as Table~1 but for the mineralogical surface
composition given by \citet{goettel}. $S_{i}$ is given in $N$~cm$^{-2}$~s$^{-1}$.}
%\centerline
{\small
\begin{tabular}{cc|cc|cc}
\hline
\hline
 & \multicolumn{1}{c}{Cintala} & \multicolumn{2}{c}{Dermott et~al.}  & \multicolumn{2}{c}{Wiegert et~al.} \\ 
 &   & BM-LB & BM-G
 &  BM-LB & BM-G  \\
 \hline\noalign{\smallskip}
 Na & $1.0537\times 10^{5}$ & $4.5641\times 10^{7}$ & $2.5483\times 10^{7}$   & $2.7661\times 10^{6}$ & $1.5444\times 10^{6}$\\
 K & $4.2243\times 10^{3}$ & $1.8298\times 10^{6}$ & $1.0216\times 10^{6}$    & $1.1090\times 10^{5}$ & $6.1917\times 10^{4}$\\
 Mg & $4.7795\times 10^{6}$ & $2.0702\times 10^{9}$ & $1.1559\times 10^{9}$   & $1.2547\times 10^{8}$ & $7.0054\times 10^{7}$\\
 Ca & $5.1513\times 10^{5}$ & $2.2313\times 10^{8}$ & $1.2458\times 10^{8}$    & $1.3523\times 10^{7}$ & $7.5504\times 10^{6}$\\
\hline
\end{tabular}}
\tablebib{(1) \citet{goettel}.}\vspace{2mm}
\end{table}