English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Lead-zinc mines and prospects in the Municipio de Januaria, in. northern Minas Gerais, Brazil, are scattered along both sides of the Eio SSo Francisco for more than 100 kilometers. Seven deposits of lead and zinc and one fluorite prospect are grouped in a small area from 10 to 15 kilometers west of the village of Itacarambi. Others lie in a wide area surrounding the city of Januaria, of which only two small occurrences are described in this report, Production of lead from these deposits has been small and discontinuous, totaling only a few tons of lead and several hundred kilograms of silver. In 1957, the surface zone of residual blocks of oxide ore at Mina Janeiro, west of Itacarambi, was explored; several thousands tons of hand-sorted ore was stockpiled and a few hundred tons was shipped to Bio de Janeiro for pilot-plant extraction of zinc. In the same year, a fluoride deposit near Mina JanelSo was explored. Reserves of the deposits west of Itacarambi are judged to be small on the basis of surface showings; those of deposits near Janudria are considered to be of no commercial importance. Sedimentary rocks in the Januaria region include the Bambui series and the Bauru formation. The Bambui series consists of flat-lying carbonate and finegrained clastic rocks of possible Ordovi'cian or Silarian age. The base of the series is not exposed. A section of part of the Bambui series west of Itacarambi is 520 meters thick. The lower half includes six limestone and dolomite units of various types; the upper half is composed mainly of calcareous siltstone, and mudstone. West of the city of Januaria, the Bambui series consists of substantially the same units but the section is only 104 meters thick. The Bambui series east of the Rio Sao Francisco in the section at Alto de Palmeiras is 210 meters thick and copsists mainly of calcareous mudstone and siltstone, with some interbedded. dark-gray limestone. The Bauru formation of Cretaceous age overlies the Bambui series. It is continental in origin and consists of massive, fine-grained red-bed sandstone and small amounts, of siltstone containing variable proportions of calcareous, siliceous, and limonitic cement. The Bauni formation characteristically caps buttes and mesas; near the city of Januaria it is 90 ineters thick. M.ost strata of the Janu&ria region are only slightly warped or faulted. West of Itacarambi, a broad anticline that is 6 tP 8 kilometers in length, trends N,

Geology of the lead-zinc deposits in the Municipio de Januaria, State of Minas Gerais, Brazil