geochemical investigation of trace elements in crude oil and core well rocks of the southern east in iraq

The concentrations of trace metals in crude oil samples and core well rocks obtained from five oil fields: halfaya, noor, amara, north, and south buzurgan, were analyzed using an atomic absorption spectrophotometer. the results showed the ranges of the trace transition elements are in core well rocks in the order ni (4.292-7.113 ppm), fe (2.541-4.256 ppm), zn (0.953- 2.056 ppm), co (1.262-1.38 ppm), cu (0.181-1.31 ppm), cd (0.419-0.71 ppm), mn (0.278- 0.387 ppm), cr (0.217- 0.343 ppm), pb (2.508- 31.333 ppm), sn (0.149-0.537 ppm), the metalloid (0.105-0.212 ppm), the alkaline metals ca (14.19- 19.31 ppm), mg (9.205- 10.55 ppm), ba (3.989-6.928 ppm), the alkali metals k (7.395-13.52 ppm), and li (0.842- 1.134 ppm). while in crude oil , the order v was in the range (2.523- 102.741 ppm), ni in the range (20.143-28.103ppm), zn (5.142- 8.723 ppm), fe (2.016- 5.872 ppm), mn (0.756- 1.042 ppm), co (0.483-0.924 ppm), cu (0.2830- 0.871 ppm), cr (0.283- 0.731 ppm), cd (0.1870- 0.631 ppm), alkaline metals ca (4.441- 9.424 ppm), mg (3.869-9.724 ppm), ba (2.211- 3.792 ppm), alkali metals k (4.122- 6.631 ppm), and li (2.175-4.897 ppm). the post-transition metals pb was in the range of (3.631-9.892 ppm), sn (0.189-0.312 ppm), and metalloid in the range of (0.106-0.252 ppm). trace element ratios ca/mg, mg/ca, mn/ca, and cr/ni, were used to unravel the genetic correlation among the core well rocks and v/ni, v/(v +ni) ratios showed marine origin and oxic conditions of the crude oil.