The discovery of the Atlantida Cu-Au-Mo porphyry deposit is a recent example of exploration success under cover in a traditional mining jurisdiction. Early and appropriate acquisition of geophysics ...was a key tool in the discovery and in guiding resource definition drilling through the lifecycle of the project. Close review of the geophysical response of the deposit with respect to its lithological distribution and petrophysical properties has allowed it to be fully characterised despite no mineralisation being exposed at surface. Data acquired over the project includes induced polarisation, ground and airborne magnetics, gravimetry and petrophysics.
The distribution of the key lithologies is demonstrated to be readily defined via a combined application of susceptibility and density properties, which agree well with geophysical data acquired at surface. This is in contrast to the electrical properties which instead map the extent of mineralisation associated with the hydrothermal system via chargeability, and the location of copper bearing sulphides via resistivity
In combination these characteristics can be used to infer depth to exploration targets and potential for high grade mineralisation in a geological context. Future exploration will be increasingly reliant on the understanding of the surface manifestations of buried deposits in remotely acquired data. This review summarises the application and results of these principles at the Atlantida project.
This paper analyzes one of the boldest editorial ventures checked early in the deployment of modern information journalism from American and French matrices. The magazine Atlantida: mensario ...artistico, literario e social para Portugal e Brazil was edited by two of the leading journalists of both countries, João do Rio and João de Barros (1915-1920) under the auspices of the respective governments. This proposal aims to raise elements of the press and culture and the media history. As daily journalism takes a turn prioritizing the most informative aspect, magazines emerge as space also dedicated to vehicular opinion and other media. How are methodological experience and innovation, national and international historiography (speci cally in the history of printing), history of culture and the media interrelated? This magazine is inserted in-depth discussion on the Brazilian national identity, especially in response to the growing “antilusitanismo” reaching the climax in 1922. Therefore, we will describe the constituent elements of the magazine concerning its historical moment.
The Turonian age in the Pelotas Basin is represented by the Atlântida Formation, which consists mainly of marine dark shales and siltstones with intervening layers of carbonates. It has yielded a ...neritic fish assemblage that includes lamniform, pycnodontid, cladocyclid, clupeomorph, basal euteleostean, dercetid, enchodontid and holocentrid remains. In this assemblage there is a small fish, here described as
Parawenzichthys minor gen. et sp. nov. It is characterized by having a low and elongate body, prominent snout, drop-shaped nasal, smooth dermal bones, toothless jaws, a mandible-suspensorium joint placed at the posterior portion of the orbit, very small pleural ribs, and at least 50 smooth vertebrae. Although superficially very similar to
Santanasalmo elegans, known from the Albian of the Araripe Basin, it is separated by a combination of features of skull and, particularly, in the caudal endoskeleton. The first uroneural shows reduced anterior outgrowth and is fused to the compound centrum (first preural + ural centra), and the second uroneural is very long. There are six hypurals, the first of which is the largest. Taking into account the presence of derived conditions in the skull and caudal endoskeleton, the fish is assigned to Protacanthopterygii, sharing certain derived features with the argentinoid
Wenzichthys congolensis from the non-marine Lower Cretaceous of Gabon (Africa).
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Parawenzichthys minor is a very small fish reaching about 30 mm estimated body length. ► It shares with
Wenzichthys congolensis toothless jaws, parasphenoid, and vomer, and compound centrum. ► It was tentatively assigned to Argentinoidei (Protacanthopterygii), due to the absence of stegural.
We describe
Speleonectes atlantida
n. sp. as the third species of Remipedia that was found outside the main distribution area of this group in the Caribbean region.
S. atlantida
was collected by cave ...divers equipped with closed circuit rebreathers from the far interior of the Túnel de la Atlántida, an anchialine volcanic lava tube, on the Canarian island of Lanzarote. The new species occurs in sympatry with
S. ondinae
, to which it is morphologically closely related.
S. atlantida
can be distinguished from
S. ondinae
by a more slender habitus and smaller pleurotergites in the posterior trunk. The valid status of
S. atlantida
as a new species of Remipedia could be corroborated by intra- and interspecific comparisons of 16S rDNA and CO1 sequence data.
: Dercetid fishes are common in Tethyan marine deposits of Europe, Asia and Africa. In this paper, we describe a South American dercetid fish, Brazilodercetis longirostris gen. et sp. nov., based on ...juvenile and adult specimens found in core samples at c. 4000 m sediment depth in the Atlântida Formation (Pelotas Basin, southern Brazil). Brazilodercetis longirostris is a slender, elongate fish recognized on the basis of the following features: prominent snout; contact between mesethmoid and frontals very anterior to the orbit; mesethmoid separating the premaxillae for half of their length; juvenile specimens bearing wedge‐like teeth on the anterior third of maxilla; long and shallow crest crossing epioccipital, parietal and posterior border of frontal; a pipe‐like preopercle; and reduced neural spine at the middle point of neural arch. Brazilodercetis shares a number of features with the other dercetids, including a pointed snout that is longer than the lower jaw (with Rhynchodercetis and Hastichthys), a medioparietal skull roof (with Cyranichthys and Benthesikyme), an unroofed posttemporal fossa (with Dercetoides, Rhynchodercetis and Pelargorhynchus), a flange on the anguloarticular (with Dercetoides, Hastichthys, Rhynchodercetis and Cyranichthys), untoothed premaxillae (with Hastichthys and probably Rhynchodercetis), and a single row of teeth on the maxillae (with Dercetis, Benthesikyme, Rhynchodercetis, Pelargorhynchus, Dercetoides and Hastichthys).
The first holocentroid fish from South America, Pelotius hesselae gen. et sp. nov., is described from the Turonian of the Atlântida Formation, Pelotas Basin, southern Brazil. It is a small fish ...preserved in a dark gray neritic shale from a drill-core sample collected at a depth of around 4,000 m. The inclusion of P. hesselae in the Holocentroidei is supported by the presence of four spines in the anal fin, the penultimate one being the longer, and an expanded neural spine of the fourth preural centrum. Although preservation is insufficient to permit detailed morphological description of the skull and caudal skeleton, the high number of dorsal spines (10), the median suture in the posterior portion of the pelvic bone, and the presence of seven rays in the pelvic fin exclude Pelotius from the Trachichthyoidei, Stichocentridae and Pycnosteroididae and suggest its inclusion in the Holocentridae. On the other hand, it shares with the clade Erygocentrus + Tenuicentrinae + Myripristinae + Holocentrinae the apomorphic presence of two predorsals. Pelotius hesselae is distinguished from all other known holocentroids by having unusual coarse ornamentation in the anterior edge of preopercular and opercular, and lateral portion of the maxilla.