Zinc-lead mineralization in northern and northeastern Iraq

الملخص EN

This is a review paper on zinc-lead deposits and occurrences in northern and northeastern Iraq.

These deposits can be genetically classified as low-temperature hydrothermal strata-bound deposits composed of simple sulfide ores of Zn-Pb, commonly associated with barite in the Northern (Ora) Thrust Zone, and as volcano-sedimentary deposits, composed of Zn-Pb-Cu-Fe sulfide ores and Zn-Fe skarns in the Shalair Terrain, NE Iraq.

The former deposits are hosted in carbonates of wide age range (Permian – Tertiary), whereas the later (Marabasta) is found in phyllites of the Triassic imbricates.

The Zn-Pb mineralizations of Iraq form part of the Alpine Metallogenic Belt extending from the Atlantic Ocean in the west to Iran in the east.

They are forming local metallogenic provenances in northern and northeastern Iraq, running parallel to the main fold and thrust belt direction in the north and the Zagros suture in the northeast.

Most of them are classified as strata-bound deposits where structure and lithology were the main physical factors controlling the distribution of these deposits.

Faults, joints, fractures and permeable strata acted as paths in the transportation of the ore-bearing solutions.

Generally, the low-temperature strata-bound deposits of N Iraq are dominated by sphalerite, galena, barite and pyrite with smithsonite, cerussite and goethite as weathering products, while the ore mineralogy in the volcano-sedimentary and skarn deposits in NE Iraq is represented by galena, sphalerite, pyrrhotite, marcasite, arsenopyrite, pentlandite, magnetite, willemite, gahnite and garnet.

Limonitic gossans are common phenomena in the oxidized zones of these deposits and occurrences.

The mostly studied of these deposits are the Duri-Serguza deposit, described as epigenetic low-temperature strata-bound hydrothermal mineralization, and the Marabasta deposit which was described as a volcano-sedimentary strata-bound deposit, partly developed, by low-grade metamorphism, into a skarn deposit.

The Iraqi Zn-Pb-barite deposits and occurrences have not yet been proved to be economic, but they may become a potential source for some metals after further exploration.