It might be better if you use values for the terrestrial surface, which can significantly vary from the values of the upper crust. You may also differentiate varying lithologies. We calculated some values you could use two years ago (see linked open access publication). However, the contained tables might contain only some of the heavy metals you are interested in.

Best regards, Nils

http://link.springer.com/article/10.1007%2Fs00531-010-0635-x

Article The geochemical composition of the terrestrial surface (with...

I suggest you to use chemical partitioning technique to develop local standards form metals in near shore sediments.

Thanks Dr. Nils 

Dear Dr. Karbassi . i did the analysis on the shallow marine sediments and i have a local concentrations  for the heavy metals at the study area , but i want to compare the result to a standard values of heavy metals . i miss understand what did you mean by Chemical partitioning technique 

Dear Dr Mounir El-Kahawy.

A world-wide standard for heavy metals in coastal area does not exist. You can compare your data to the continental crust as proposed, but this comparison has no real meaning because the lithology of the watersheds around your coast could be different from the CC. You can also compare your data to references values used for toxicity. But I guess that the best for you will be to make a comparison with some other data that you must find on litterature and which have been measured nearby your area. The trace metal content depend on many parameters including sand, clay, carbonate and organic matter fraction, and obviously on the anthropogenic inputs. The variability within the coastal zone could be thus very high, even on a small area.

One approach is to use pre-industrial levels from the area where you have your samples. Of course this implies that or you have data on this pre-industrial period or that you date your sediments using 210Pb or 217Cs to find the basal non-anthropogenic levels.

Thanks a lot Dr. Olivier for your outstanding Answer . wish for you the best

Thanks so much Dr. Bernardo for your answer 

By chemical partitioning analysis you can know about the association of metals with various sedimentary phases. Therefore, you would be able to separate lithogeneous fractions from anthropogenic ones. In this way, you will be able to develop standards for your area of study. 

I suggest you to use mean shale values. Since you are working on a coastal area, she will give you a good correlation with reality. Meanwhile you may use a rock which covers most of the watershed. In an research in south Iran, I used carbonate rock values as the reference since carbonates cover more than 70% of the area. If you are working in a sedimentary or mafic igneous terrain, CC underestimate or overs\estimate some elements.

Dear Dr. Soroush i would use it but the bottom facies of the shallow marine area in the area of study not a shale but it's mostly mudy silt and silty sand  facies . so i hope to ask is it right if i  depend on the average shale values although the facies is mudy silt  and sandy .

Regards

I Think it is acceptable for silt. However for sandy facies, do you think that the sands are composed of shell debris (carbonates) or other materials?  Then i recommend you to use accordingly. 

yes  Dr. Soroush, The sand facies composed of shell debris with ranges between 12-53 % of carbonates .

Then in such a condition I use carbonate reference values

Thank you a lot Dr. Soroush  for your Answer . wishing for you the best .