“Ponta Da Ferraria E Pico Das Camarinhas” Geosite (São
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Geoheritage DOI 10.1007/s12371-016-0203-2 ORIGINAL ARTICLE Monitoring of the Visitors Impact at BPonta da Ferraria e Pico das Camarinhas^ Geosite (São Miguel Island, Azores UNESCO Global Geopark, Portugal) Ana Lima1 & João Carlos Nunes2 & José Brilha3 Received: 19 April 2016 /Accepted: 17 October 2016 # The European Association for Conservation of the Geological Heritage 2016 Abstract BPonta da Ferraria e Pico das Camarinhas^ is a Keywords Azores UNESCO Global Geopark . Monitoring . protected geosite in São Miguel Island in the Azores archipel- Geoconservation . Carrying capacity . Geosite ago, Portugal. Due to its importance for the geoconservation strategy of the Azores UNESCO Global Geopark, monitoring actions of visitor impact were implemented in order to assure Introduction that the main geological features of this geosite continue to be in a favourable status of conservation, taking into account In everyday language, monitoring can be interpreted as the act present public use. Different types of data were collected over of measuring a certain topic. This activity can be based on a one-year period aiming at the identification of factors that systematic observations of certain aspects related to a specific may affect the geosite and also the assessment of the eventual problem in order to gather information on the characteristics decrease of relevance that this geosite has experienced of this problem and its evolution over time (Spellerberg 1991). throughout that period. Among the many geological features The repetition of measurements or observations over time for that occur in the geosite, the littoral cone (or pseudocrater) was the purpose of detecting changes distinguishes monitoring considered the most threatened due to its uniqueness and high from inventory and assessment. An inventory or assessment vulnerability. The number of visitors was also analysed with is usually the first step for the establishment of a monitoring respect to the geosite’s carrying capacity. The monitoring of project, since the knowledge of the spatial and temporal char- this geosite allowed the definition of practical actions, in par- acteristics of the study area is essential to develop an efficient ticular to be addressed to the governmental agency who is monitoring strategy (MacDonald et al. 1991). A vast range of responsible for the management of this geosite. features can be monitored in natural sciences, including veg- etation growth, animals’ behaviour, climate variations, earth- quakes or volcanic events. Also, geoconservation strategies (Henriques et al. 2011) use monitoring to understand the evo- * Ana Lima ’ [email protected] lution of a geosite s relevance over time (Wimbledon et al. 2004, García-Cortés et al. 2012,Brilha2016, Díez-Herrero João Carlos Nunes et al. 2015, Vegas et al. 2015). [email protected] Monitoring is an important tool in environmental planning José Brilha and management because it provides the necessary information [email protected] to determine if a resource or a process continues to be affected by a certain threat, or otherwise, is recovering due to the imple- 1 Earth Sciences Centre, University of Minho, Campus de Gualtar, mentation of appropriate management practises (Marion and 4710-057 Braga, Portugal Leung 2011; García-Cortés et al. 2012; Vegas et al. 2015). 2 University of Azores & Azores UNESCO Global Geopark, Rua Mãe The monitoring of management plans aims to check if their de Deus, 9501-801 Ponta Delgada, Açores, Portugal objectives are being met, if the selected strategies are the most 3 Institute of Earth Sciences, Pole of the University of Minho, Campus adequate to meet the objectives and if the proposed actions de Gualtar, 4710-057 Braga, Portugal were effectively implemented (Portugal 2002). Geoheritage This paper presents and discusses an assessment of visitor São Jorge, Pico, Faial and D. João de Castro Bank (a submarine impact between October 2011 and October 2012 at the BPonta da volcano between Terceira and São Miguel islands). On these 27 Ferraria e Pico das Camarinhas^ Natural Monument, one of the volcanic systems, there are about 1750 monogenetic volcanoes, geosites in the Azores UNESCO Global Geopark (Lima 2012). either dispersed along the flanks and inside the depressions in the summit of the polygenetic volcanoes or on the fissural ba- Azores UNESCO Global Geopark saltic systems. These monogenetic volcanoes include domes and coulées, tuff rings and tuff cones, maars, scoria and spatter The Azores archipelago is a Portuguese Autonomous Region cones and eruptive fissures (Lima et al. 2010). located in the North Atlantic, on the triple junction between The international relevance of the Azorean geodiversity, the North American, Eurasian and African (or Nubian) plates. the high number and scientific importance of the geological It is composed of nine islands, some islets and the surrounding heritage, together with the rich biological and cultural heritage seafloor. The islands can be divided into three groups: the constituted the background for the Azores government deci- Western Group with the Corvo and Flores islands, the sion to implement a geoconservation strategy through the cre- Central Group with Faial, Pico, São Jorge, Graciosa and ation of the Azores Geopark (Lima 2009), which was integrat- Terceira islands and the Eastern Group with São Miguel and ed in the European and Global Geoparks Networks (EGN/ Santa Maria islands (Fig. 1). GGN) in March 2013. Lima et al. (2010) have identified ThevolcanicislandsoftheAzorespresentawiderangeof 121 geosites in the nine islands and the surrounding sea floor, landforms, reliefs and structures due to the type of eruptions and with international, national and regional relevance. Based on rocks produced and subsequent weathering and erosion (Lima this inventory, 57 main geosites were selected to be included 2009). They are characterized by 16 major polygenetic volca- in the management strategies of the Azores UNESCO Global noes and 11 fissural basaltic systems, nine of them being active Geopark. BPonta da Ferraria e Pico das Camarinhas^ geosite is and located in the islands of São Miguel, Terceira, Graciosa, one of these geosites. Fig. 1 Location of the Azores archipelago, Portugal Geoheritage BPonta da Ferraria e Pico das Camarinhas^ Geosite lava delta, Moore (1991) describes a tristanite lava flow in the fossil sea cliff with 74,000 ± 6000 years B.P. (Fig. 2). BPontadaFerrariaePicodasCamarinhas^ geosite is located During the movement of the lava flow into the sea, water in the westernmost sector of São Miguel Island (Fig. 1 and steam accumulated underneath the lava flow. This steam pro- Fig. 2). Pico das Camarinhas (Fig. 3) is a basaltic scoria cone duced small explosions on the top of the lava delta forming a with three craters on the summit, elongated along a general W- structure with conical shape, but without a feeding conduit. E trend, which defines a radial tectonic alignment of the Sete This structure known as littoral cone or pseudocrater (Fig. 3)is Cidades central volcano. Ponta da Ferraria (Fig. 2 and Fig. 3) extremely fragile and very rare in the Azores archipelago is a lava delta formed by basaltic lava flows, which erupted (Nunes and Lima 2009). fromPicodasCamarinhasmonogeneticvolcano840 ±60years Rocks of Ponta da Ferraria lava flow have a very high ago, during one of the 46 flank eruptions of Sete Cidades concentration of xenoliths/cumulate with a relatively homo- volcano (Moore 1991; Nunes and Lima 2009). This lava delta, geneous mineralogical composition (plagioclase and amphi- also named as Bfajã^ in the Azores, has a typical triangular boles) but with diversified textures. Also, at the northern part shape, a finger-like shoreline contour, and is characterized by of the fossil sea cliff and dispersed in the ankaramitic lava vertical plunging sea cliffs in most of its contour. It has an area flow and scoria deposit of Várzea Cone (5000 and of 129,431m2 and an altitude of about 15 m in the central part 15,000 years), there are ultramafic xenoliths of granular rocks (Nunes and Lima 2009). According to Carvalho et al. (2009), rich in olivine and pyroxene, which were initially formed deep the Ponta da Ferraria lava flow has a thickness of about 20 m, in the mantle (Nunes and Lima 2009). with top and bottom clinkery layers. East of Pico das Camarinhas scoria cone, there is an older There is a fossil sea cliff (Fig. 3) where geological forma- volcano, a trachytic dome (Fig. 3) associated with the same tions of Sete Cidades volcano can be observed, namely, ba- radial fracture of Sete Cidades volcano. Both volcanoes were saltic and trachytic s.l. lava flows, lapilli and pumice deposits, fed through the same magmatic chamber, but they represent ignimbrites and sub-vertical dykes (Nunes and Lima 2009). two different lithological compositions, trachyte and basalt Near the natural thermal pool at the southernmost part of the (Nunes and Lima 2009). Fig. 2 Geological map of the Ponta da Ferraria area (Nunes and Lima 2009) Geoheritage Fig. 3 Main geological features at “Ponta da Ferraria e Pico das Camarinhas” geosite. a Fossil sea cliff. b Pico das Camarinhas scoria cone. c Littoral cone (or pseudocrater). d Trachyte lava dome. e Ponta da Ferraria lava delta. f Natural thermal pool In addition to these geological features, at the southernmost geographical, biological, scenic and socioeconomic impor- part of Ferraria lava delta, water emerges at the sea level with a tance. Concerning the scientific value, this geosite occupies temperature of 62.5 °C (Carvalho et al. 2009); (Fig. 3). the 14th position among all the 121 geosites of the Azores Despite the inexistence of subaerial gas emissions in Sete Geopark and the third position among the 27 geosites of São Cidades volcano, submarine fumaroles are known near the Miguel island (Lima 2007; Nunes et al. 2011). Presently, it is Ferraria and Mosteiros coastal areas (Carvalho et al. 2009). used for educational, cultural, tourism and science activities; The Ferraria thermal water has physicochemical characteris- its economic importance is related with the existence of a local tics compatible with an origin resulting from a mixture of spa as a private business (Lima et al.