{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,7,16]],"date-time":"2025-07-16T12:58:01Z","timestamp":1752670681923},"reference-count":0,"publisher":"Prof. Marin Drinov Publishing House of BAS (Bulgarian Academy of Sciences)","issue":"7","license":[{"start":{"date-parts":[[2022,7,29]],"date-time":"2022-07-29T00:00:00Z","timestamp":1659052800000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/copyrights.bg\/%D0%B7%D0%B0%D0%BA%D0%BE%D0%BD-%D0%B7%D0%B0-%D0%B0%D0%B2%D1%82%D0%BE%D1%80%D1%81%D0%BA%D0%BE%D1%82%D0%BE-%D0%BF%D1%80%D0%B0%D0%B2%D0%BE\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["C. R. Acad. Bulg. Sci."],"abstract":"<jats:p>Geochemical features of the deep-sea sediments from a high polymetallic nodule area in the eastern part of the Clarion-Clipperton Fractures Zone (CCZ), NE Pacific were studied. Box-corer samples from six stations in individual depth layers 0\u20133, 3\u20135, 5\u201310, 10\u201320 cm were collected from 4300\u20134500 m depth. The deep-sea sediments were classified as clayey-siliceous oozes according to the mineral and grain-size analyses. The chemical composition of the studied samples is compatible with that of pelagic sediments. Manganese content varies from 0.16% to 0.70% being the highest in the geochemically active layer (top 7\u201312 cm) and decreases with depth. The Mn\/Fe ratio, Ba, Co, Ni and Cu have the highest values in the first (0\u20133) and second (3\u20135) layers and decrease with depth. REE range is 195.84\u2013357.79 ppm showing low variation between the layers. PAAS-normalized REE patterns show significant enrichment of MREE and HREE with strong negative Ce anomaly and weak positive Eu and Y anomalies. The geochemical characteristics of the studied sediments infer polygenic origin. The redox sensitive oxides and barite presense, Eh values and negative Ce anomaly, indicate oxidizing environment of sediment formation.\u00a0<\/jats:p>","DOI":"10.7546\/crabs.2022.07.10","type":"journal-article","created":{"date-parts":[[2022,7,29]],"date-time":"2022-07-29T12:42:01Z","timestamp":1659098521000},"page":"1018-1027","source":"Crossref","is-referenced-by-count":10,"title":["REE and Trace Elements Distribution in the Deep-sea Sediments from the Interoceanmetal (IOM) Polymetallic Nodule Exploration Area in the Clarion-Clipperton Fractures Zone, NE Pacific"],"prefix":"10.7546","volume":"75","author":[{"given":"Atanas","family":"Hikov","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zlatka","family":"Milakovska","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Valcana","family":"Stoyanova","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elitsa","family":"Stefanova","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomasz","family":"Abramowski","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Silvia","family":"Chavdarova","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Milen","family":"Stavrev","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"4381","published-online":{"date-parts":[[2022,7,29]]},"container-title":["Proceedings of the Bulgarian Academy of Sciences"],"original-title":[],"link":[{"URL":"https:\/\/proceedings.bas.bg\/index.php\/cr\/article\/download\/119\/119","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/proceedings.bas.bg\/index.php\/cr\/article\/download\/119\/119","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,7,29]],"date-time":"2022-07-29T12:42:03Z","timestamp":1659098523000},"score":1,"resource":{"primary":{"URL":"https:\/\/proceedings.bas.bg\/index.php\/cr\/article\/view\/119"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,7,29]]},"references-count":0,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2022,7,29]]}},"URL":"https:\/\/doi.org\/10.7546\/crabs.2022.07.10","relation":{},"ISSN":["2367-5535","1310-1331"],"issn-type":[{"value":"2367-5535","type":"electronic"},{"value":"1310-1331","type":"print"}],"subject":[],"published":{"date-parts":[[2022,7,29]]}}}