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ABSTRACT  The Brazilian speleological heritage is protected by laws, and every region where caves are present requires scientific studies to assist in environmental licensing. In the context of mining in iron formations, the near-surface geophysical studies using electroresistivity survey were performed in the cave N4E-0022, located at the N4EN iron mine, Carajas Complex, northern Brazil. The near-surface geophysical surveys generated continuous images that enhanced the lithostructural mapping of the lateritic profile, especially in places to which access by conventional methods was difficult. The electrical resistivity profiles were acquired with the dipole-dipole arrangement in the upper portion of the cave. Three sections were performed in SW-NE direction and two in SE-NW direction, totaling 435 meters of acquisition. The geoelectrical signatures were correlated with the lithologic logs of drillholes, the geophysical well logging and with the typical lateritic profile in the cave N4E-0022 surroundings. The results showed a satisfactory interpretation for the near-surface geoelectrical profiles and evolved to a comparison with the lateritic profile (lateritic crust, transition horizon, and saprolite horizon), providing inherent resistivity signatures for each modeled material. Keywords: applied geophysics, iron cave, Carajas. RESUMO  O patrimonio espeleologico brasileiro e protegido por leis, e qualquer regiao com a presenca de cavidades precisa de estudos cientificos para auxiliar o licenciamento de empreendimentos. No contexto da mineracao em terrenos ferriferos, estudos geofisicos rasos utilizando eletrorresistividade foram executados na cavidade N4E-0022, localizada no extremo norte da Mina de N4EN, Complexo Carajas. A geofisica rasa gerou imagens continuas que potencializaram o mapeamento lito-estrutural do substrato rochoso, principalmente em locais de dificil acesso aos metodos convencionais. Os perfis de eletrorresistividade foram adquiridos com arranjo dipolo-dipolo na porcao superior da cavidade. de modo paralelo entre si na porcao superior da cavidade. Tres secoes foram executadas na direcao SW-NE e duas na direcao SE-NW, totalizando 435 metros de aquisicao. As assinaturas geoeletricas das secoes foram correlacionadas com as descricoes litologicas de furos de sondagem, perfilagens geofisicas de furos de sonda e o mapeamento de detalhe do perfil lateritico no entorno da cavidade N4E-0022, evidenciando um resultado satisfatorio para as interpretacoes realizadas. Os resultados evoluiram para uma comparacao com o perfil de alteracao tipico de rochas ferruginosas (crosta lateritica, horizonte de transicao e saprolito), e forneceram assinaturas de resistividades inerentes a cada material modelado. Palavras-chave: geofisica aplicada, caverna ferrifera, Carajas.

Geoelectrical Signatures and their Relationships with the Lateritic Horizons: A Case Study of the N4EN Mine’s Iron Cave, Carajás Complex, Brazil