Puyango, Ecuador Petrified Forest, a Geological Heritage of the Cretaceous Albian-Middle, and Its Relevance for the Sustainable Development of Geotourism

Geodiversity treaties have multiplied and given rise to geological heritage as a singular value of protection and preservation for territories. The Puyango Petrified Forest (PPF) is a recognized Ecuadorian reserve, which was declared a National Heritage Treasure. It has an area of 2659 hectares, and it is located in the south of Ecuador, between the provinces of El Oro and Loja. The petrified trunks and trees were buried by volcanic lava, dating from the Cretaceous Period, 96 to 112 million years ago. Thus, silicification and carbonization, two important fossilization events, have produced hundreds of samples of paleontological wealth in Puyango. The objective of this work is to methodologically assess the geodiversity of a fraction of the PPF by registering its geological heritage and value for its preservation and sustainable development. The methodology is based on: (i) Analysis of information on the territory used for tourist visits, as a pilot study area. Presentation of paleontological components and their main sections to enhance their geotouristics value; (ii) Assessment of the geological heritage for its geotourism categorization with a recognized scientific methodology and one proposed by the co-authors propose; and (iii) Analysis of Strengths, Weaknesses, Opportunities, and Threats (SWOT) as a guide for protection and development strategies. Findings reveal the high geotourism potential for a Geopark Project in Puyango, since only 300 hectares are used for tourism and the remaining area is a virgin environment for research and improving knowledge of geodiversity and biodiversity.


Introduction
Geodiversity considers all the geological elements of the Earth's crust, from the landscape to its internal structure that constitutes the various materials such as rocks, minerals and fossils. It is an inanimate part of nature, but at the same time significant to sustaining biodiversity, since the soil and subsoil generated by a series of geological processes are what sustain it, and what together are part of the natural beauty of a site; however, geodiversity has been downplayed by historically giving Figure 1. Study area of the Puyango Petrified Forest and its geosites in the provinces of El Oro and Loja. Modified from [28].
Before becoming a tropical dry forest, Puyango was a sea, which dried up and transformed into large hectares of forests and animals. Due to natural cataclysms, geological movements and time, the organisms buried underground arose on the surface forming a trace of the planet's remote past and a transcendent number of ancient and representative fossils that correspond to marine organisms that currently oscillate between 60 and 120 million years [26]. In this regard, Puyango emerged under coastal and terrestrial marine conditions in a relatively narrow basin caused by the continuous erosive tectonism, deformation, displacement, and deposits of pyroclastic materials during the Cretaceous. Before the Andes rose to the end of the Cretaceous 65 million years ago, gymnosperm forests originated on a relatively flat area like the lithified sediments that currently lean in different directions due to folding and tectonism. During this period, the area had a warm temperature. However, with the floods and volcanic activity east of the Andes, the forests were destroyed and deposits of buried trunk layers in alternating sequences of siltstones, sandstones, graywackes and conglomerates were reestablished by erosion [29]. The Andes mountain range slowly submerged the forest, placing it south of its current position in a subtropical climate along with calcium carbonate deposits and the presence of marine fossil invertebrates belonging to shallow water. The geological formation of the site is defined as a sequence of sedimentary rocks of the Late Cretaceous period formed by thin layers of calcareous black shales, crystalline, and massive black limestones, volcanic agglomerates, gray-green siliceous shales, brown shales, and volcano-sedimentary shales ( Figure 2). In this type of Cretaceous (Albian-Middle) age materials, the petrified wood is found and in the upper part of the Coquina volcanic material, brown calcareous clays with mollusks and ammonites. In addition, a decreasing sedimentary volcanic grain sequence, clayey sandstones, tobaceous silt with petrified wood and reddish clay can be observed [30]. The trunks were dragged in an aqueous medium of remains of pyroclastic materials and deposited together with the sediments in a marine environment where they were covered by sediments as a result of the erosion of the Andes. Sediments are divided into four geological formations such as the Zapotillo, Cazaderos, Ciano, Ambín and Before becoming a tropical dry forest, Puyango was a sea, which dried up and transformed into large hectares of forests and animals. Due to natural cataclysms, geological movements and time, the organisms buried underground arose on the surface forming a trace of the planet's remote past and a transcendent number of ancient and representative fossils that correspond to marine organisms that currently oscillate between 60 and 120 million years [26]. In this regard, Puyango emerged under coastal and terrestrial marine conditions in a relatively narrow basin caused by the continuous erosive tectonism, deformation, displacement, and deposits of pyroclastic materials during the Cretaceous. Before the Andes rose to the end of the Cretaceous 65 million years ago, gymnosperm forests originated on a relatively flat area like the lithified sediments that currently lean in different directions due to folding and tectonism. During this period, the area had a warm temperature. However, with the floods and volcanic activity east of the Andes, the forests were destroyed and deposits of buried trunk layers in alternating sequences of siltstones, sandstones, graywackes and conglomerates were reestablished by erosion [29]. The Andes mountain range slowly submerged the forest, placing it south of its current position in a subtropical climate along with calcium carbonate deposits and the presence of marine fossil invertebrates belonging to shallow water. The geological formation of the site is defined as a sequence of sedimentary rocks of the Late Cretaceous period formed by thin layers of calcareous black shales, crystalline, and massive black limestones, volcanic agglomerates, gray-green siliceous shales, brown shales, and volcano-sedimentary shales ( Figure 2). In this type of Cretaceous (Albian-Middle) age materials, the petrified wood is found and in the upper part of the Coquina volcanic material, brown calcareous clays with mollusks and ammonites. In addition, a decreasing sedimentary volcanic grain sequence, clayey sandstones, tobaceous silt with petrified wood and reddish clay can be observed [30]. The trunks were dragged in an aqueous medium of remains of pyroclastic materials and deposited together with the sediments in a marine environment where they were covered by sediments as a result of the erosion of the Andes. Sediments are divided into four geological formations such as the Zapotillo, Cazaderos, Ciano, Ambín and Progreso. Marine invertebrate fossils such as gastropods, ostracods, and bivalves, which are associated with microfossils of the order of the foraminifera and calcareous nanophosiles of the Cretaceous (Middle Albian) age, are found in the layers of sedimentary materials [31]. The Puyango river is the limit between the provinces of El Oro and Loja and represents a great geological fault in the East-West direction. It has caused the folding of rocks at the gorges of El Chirimoyo, Cochurco and El Limón streams [32,33]. Progreso. Marine invertebrate fossils such as gastropods, ostracods, and bivalves, which are associated with microfossils of the order of the foraminifera and calcareous nanophosiles of the Cretaceous (Middle Albian) age, are found in the layers of sedimentary materials [31]. The Puyango river is the limit between the provinces of El Oro and Loja and represents a great geological fault in the East-West direction. It has caused the folding of rocks at the gorges of El Chirimoyo, Cochurco and El Limón streams [32,33].

Materials and Methods
The proposed methodology for this study comprised three phases ( Figure 3): (i) analysis of information from the pilot study area, the case of the Puyango Petrified Forest, scientific information regarding its geological interest, the presentation the paleontological components and their main geotouristic sections; (ii) assessment of the heritage site, using the methodology of the Spanish Inventory of Places of Geological Interest (IELIG, acronym in Spanish) and another proposal by authors to assess its geotouristics potential; and (iii) the results were confirmed with a Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis, to assess the heritage site status, and propose sustainable development strategies in the SWOT matrix [34].

Materials and Methods
The proposed methodology for this study comprised three phases ( Figure 3): (i) analysis of information from the pilot study area, the case of the Puyango Petrified Forest, scientific information regarding its geological interest, the presentation the paleontological components and their main geotouristic sections; (ii) assessment of the heritage site, using the methodology of the Spanish Inventory of Places of Geological Interest (IELIG, acronym in Spanish) and another proposal by authors to assess its geotouristics potential; and (iii) the results were confirmed with a Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis, to assess the heritage site status, and propose sustainable development strategies in the SWOT matrix [34].

First Phase: Identification of the Pilot Area
In the first phase, the researchers realized a technical visit about the outstanding characteristics of the studied forest, which was carried out with a tourist guide and some national tourists. The route of the place consists of six stations of great geological and paleontological interest, in addition to the collection of historical and scientific information carried out in the sector [26,29,30] through the configuration of a database in scientific publications, works outreach, project reporting and data collection through expert interviews as the basis for further evaluation. This route included the use of database in Geographic Information Systems (GIS) to obtain a map of the tourist route recorded in the Puyango forest.
Finally, this phase included the description geological, paleontological aspects and relevant observations of the geotouristics potential of seventeen possible geosites. We also presented its paleontological components that give the forest an important scientific interest for geologists and paleontologists. Much of its evidence was recorded in fossils such as petrified wood samples and remains of mollusc shell moulds that were found in some streams belonging to the provinces of El Oro and Loja, giving great geotouristics interest to the forest. Besides that, a stratigraphic column belonging to the Las Concreciones stream was described, and finally, it showed pictures of marine fossil invertebrates of the classes of pelecypod and cephalopod molluscs.

Second Phase: Quantitative and Qualitative Evaluation
Moreover, the applied methodology comprises two factors: (1) intrinsic value of the Site of Geological Interest (LIG, acronym in Spanish), highlighting the geological aspects, and (2) use-value of the LIG. Therefore, with the collaboration of paleontologist Nelson Jiménez and archaeologist Jorge Marcos, experts who evaluate the scientific, didactic and touristic premises value, surveys are collected. The experts assign weights to each premise of the methodology developed in [18] (Table  1), where the degrees of Scientific interest (Si), Didactic interest (Di) and Touristic interest (Ti) are obtained. The scores of each parameter vary from 0, 1, 2 and 4, where 0 is the lowest score and 4 the highest, scores that are multiplied by the weight of the individual interests given in the methodology (Table 1).

First Phase: Identification of the Pilot Area
In the first phase, the researchers realized a technical visit about the outstanding characteristics of the studied forest, which was carried out with a tourist guide and some national tourists. The route of the place consists of six stations of great geological and paleontological interest, in addition to the collection of historical and scientific information carried out in the sector [26,29,30] through the configuration of a database in scientific publications, works outreach, project reporting and data collection through expert interviews as the basis for further evaluation. This route included the use of database in Geographic Information Systems (GIS) to obtain a map of the tourist route recorded in the Puyango forest.
Finally, this phase included the description geological, paleontological aspects and relevant observations of the geotouristics potential of seventeen possible geosites. We also presented its paleontological components that give the forest an important scientific interest for geologists and paleontologists. Much of its evidence was recorded in fossils such as petrified wood samples and remains of mollusc shell moulds that were found in some streams belonging to the provinces of El Oro and Loja, giving great geotouristics interest to the forest. Besides that, a stratigraphic column belonging to the Las Concreciones stream was described, and finally, it showed pictures of marine fossil invertebrates of the classes of pelecypod and cephalopod molluscs.

Second Phase: Quantitative and Qualitative Evaluation
Moreover, the applied methodology comprises two factors: (1) intrinsic value of the Site of Geological Interest (LIG, acronym in Spanish), highlighting the geological aspects, and (2) use-value of the LIG. Therefore, with the collaboration of paleontologist Nelson Jiménez and archaeologist Jorge Marcos, experts who evaluate the scientific, didactic and touristic premises value, surveys are collected. The experts assign weights to each premise of the methodology developed in [18] (Table 1), where the degrees of Scientific interest (Si), Didactic interest (Di) and Touristic interest (Ti) are obtained. The scores of each parameter vary from 0, 1, 2 and 4, where 0 is the lowest score and 4 the highest, scores that are multiplied by the weight of the individual interests given in the methodology (Table 1). Then, the total provides the value of Si, Di and Ti. If the LIG exceeds 266 points, it is considered a place of "Very high" interest. Hence, the scores between 134 and 266 will be of "High" interest, and those lower than 134 points will be considered to be of "Medium" interest. Furthermore, a qualitative evaluation about conservation of the site is achieved, where the Susceptibility of Degradation (SD) of the site is evaluated based on the Fragility (F) and the vulnerability due to anthropogenic Threats (T). With the SD, researchers can obtain the Protection Priority (PP) for Si, Di, Ti of the LIG and rank the interests according to the PP value in its different vertices: scientific (SPP), didactic (DPP), touristic-recreation (TPP), and global (PP). Taking the threshold of the pilot project in the Iberian Cordillera [18] for a given value of the SD as reference, if the value is higher than 26, the PP degree "High" of the LIG. If the SD is equal to 26, the PP degree is "Medium". The "Medium-high" and "Medium-low" PP will be around 8. To obtain the values of fragility (F) and threat (T) that allow prioritizing and monitoring of the conservation status, where it is susceptible to degradation, and to quantify the priorities SPP, DPP, TPP, and PP, the researchers used the following equations: Moreover, the authors include a completed form of the proposed methodology that includes the Scientific, Didactic, Tourist and Popular Interest factors with Accessibility, Sensitivity and Conservation status (SDTPI-ASC), considering the 17 LIGs of relevant geological-paleontological importance. This approach strengthens the evaluated geological heritage. For this purpose, the interest categories are divided into Scientific interest (Si), Didactic interest (Di) and Touristic interest (Ti) and Popularization interest (Pi), with its sections on accessibility to the place, sensitivity to plunder and current conservation status, as a basis for future studies.

Third Phase: Strategies
In this phase, based on expert judgment, the SWOT matrix configuration was done, with experiences from technical visits and studies in the Puyango Petrified Forest (BPP). This matrix allows establishing opportunities for geotourism development, identifying strengths, weaknesses and threats. The particular singularity of the territory in its geological and paleontological heritage has been highlighted, with a high interest for national and international geologists interested in investigating the geological record of the place, the scientific, educational and recreational use to strengthen the local economy.
There is a high fossil content, pleated structures, sedimentary, volcanic, metamorphic rocks with a natural, integral and biodiverse perspective, with samples of petrified trunks, pelecypods, macrofossils and ammonites. In the analysis of experts, the limitations or problems of the geosites are also considered, to turn them into new strategies for local development.
A SWOT analysis was carried out to assess the conservation status of the heritage site and to propose sustainable development strategies in a SWOT matrix [34], where the Puyango geopark project has great potential to promote the development of geotourism in the zone.

Identification of the Pilot Area
The identification of the pilot area includes the visit of the tourist trail carried out in the Puyango Petrified Forest (PPF), in the province of El Oro. This guided route lasts approximately 45 min and observation stops are made at the stations: (1) Lava flows, (2) Path of the Araucarias, that is a genus of evergreen coniferous trees in the family Araucariaceae, (3) Deposit of petrified logs, (4) Carboniferous zones, (5) Path of the Giant, and (6) Giant Petrine (Figure 4). macrofossils and ammonites. In the analysis of experts, the limitations or problems of the geosites are also considered, to turn them into new strategies for local development.
A SWOT analysis was carried out to assess the conservation status of the heritage site and to propose sustainable development strategies in a SWOT matrix [34], where the Puyango geopark project has great potential to promote the development of geotourism in the zone.

Identification of the Pilot Area
The  For a better scientific reference about LIGs, Table 2 details the important geological aspects such as geological structures and type of rocks found in the geosite, as well as paleontological aspects that stand out for their fossil content, the type of fossilization and the number of petrified trunks found in each geosite which makes it an excellent geotouristic remnant.  For a better scientific reference about LIGs, Table 2 details the important geological aspects such as geological structures and type of rocks found in the geosite, as well as paleontological aspects that stand out for their fossil content, the type of fossilization and the number of petrified trunks found in each geosite which makes it an excellent geotouristic remnant.
Some of the LIGs mentioned in Table 2 belong to the province of El Oro, such as the streams Sábalos, Las Palmas, El Tigre, El Guineo, El Gringo, Quemazón and in the province of Loja are the El Chirimoyo, Cochurco, El Limón, Las Concreciones and Tunima ( Figure 5). In the Cochurco, El Chirimoyo and Las Concreciones streams, remains of mollusk shell molds such as pelecypods and ammonites have been found in the limestones [26].  Some of the LIGs mentioned in Table 2 belong to the province of El Oro, such as the streams Sábalos, Las Palmas, El Tigre, El Guineo, El Gringo, Quemazón and in the province of Loja are the El Chirimoyo, Cochurco, El Limón, Las Concreciones and Tunima ( Figure 5). In the Cochurco, El Chirimoyo and Las Concreciones streams, remains of mollusk shell molds such as pelecypods and ammonites have been found in the limestones [26]. Moreover, a stratigraphic column of the Las Concreciones stream is shown ( Figure 6) as a result of the scientific research carried out in. The stream adopted that name because at the beginning of the stream, precisely upstream, there are concretions of limestone rolled from the upper part, whose outcrop is made of sedimentary material. On the shales, limestones, marls and thin layers of clay are observed. Limestone concretions of 0.80 m in diameter are observed in the rock with a light gray hue. The limestones are crystalline with pyrite as a mineral. In addition, the concretion of two Ammonite molds lie, and a large limestone outcrop approximately 7 m thick stands out at the end of the station Moreover, a stratigraphic column of the Las Concreciones stream is shown ( Figure 6) as a result of the scientific research carried out in. The stream adopted that name because at the beginning of the stream, precisely upstream, there are concretions of limestone rolled from the upper part, whose outcrop is made of sedimentary material. On the shales, limestones, marls and thin layers of clay are observed. Limestone concretions of 0.80 m in diameter are observed in the rock with a light gray hue. The limestones are crystalline with pyrite as a mineral. In addition, the concretion of two Ammonite molds lie, and a large limestone outcrop approximately 7 m thick stands out at the end of the station [27].  The fossil invertebrates are marine and belong to the pelecypods and cephalopod classes of mollusks ( Figure 7). The cephalopod class is represented by ammonoids represented by the internal and external molds as well as petrified shells in the Cochurco, El Chirimoyo, El Limón, Las Concreciones, and El Guineo streams. The internal molds of mollusks with Nucula spp, Inoceramus concentricus, Astarte spp and Heterodontido (See Supplementary Figures S1-S4) [26]. The fossil invertebrates are marine and belong to the pelecypods and cephalopod classes of mollusks (Figure 7). The cephalopod class is represented by ammonoids represented by the internal and external molds as well as petrified shells in the Cochurco, El Chirimoyo, El Limón, Las Concreciones, and El Guineo streams. The internal molds of mollusks with Nucula spp, Inoceramus concentricus, Astarte spp and Heterodontido (See supplementary Figures S1, S2, S3, S4) [26].

Evaluation
The results of phase ii with the scientific, didactic and touristic interests are presented according to the IELIG methodology with its justification in Table 3.
To obtain the value of each item of interest, Equations (1)-(3) were used. Results reveal that the Puyango Petrified Forest presents a "Very high" and "High" global degree of interest in the Scientific (Si), Didactic (Di) and Touristic (Ti) aspects. Although some of them have a "Middle" public interest (Figure 8), the reason is that the lack of strategies that promote the geodiversity of the area through geotourism. Population density (potential aggression) The town is located at the entrance to the forest tourist complex that belongs to the province of El Oro, Las Lajas canton. It has an economically active population of approximately 200 people, mostly farmers [26].
To obtain the value of each item of interest, Equations (1)-(3) were used. Results reveal that the Puyango Petrified Forest presents a "Very high" and "High" global degree of interest in the Scientific (Si), Didactic (Di) and Touristic (Ti) aspects. Although some of them have a "Middle" public interest (Figure 8), the reason is that the lack of strategies that promote the geodiversity of the area through geotourism. The results of the applied evaluation of the IELIG methodology are represented in Table 4, noting that there are four LIGs with Geological Interest (IG) "Very High", nine of interest "High" and four "Medium", reflecting the great relevance of the Puyango Petrified Forest. The Global Protection Priority (PPG) values are also shown, finding most of the LIGs with the rating of "Medium-low".

Representativeness
The Puyango Petrified Forest (PPF) is a source of knowledge and well-being and it is the unique place with the best paleontological exposure in Ecuador. The area shows a sequence of volcano-sediment from the Cretaceous age (Albian-Middle). A collection of petrified trunks, fossilized leaves of common gymnosperms and remains of mollusk shell molds of the Southern Cretaceous have been found in PPF deposits.

Prototype location character
PPF is a site of geological interest and a good example of a paleontological deposit, where specimens of petrified trunks and other allochthonous from Aptian-Middle and Jurassic-Cretaceous are found in situ.

Degree of scientific knowledge of the place
There are several works published in national and international journals performed by geoscientists and theses carried out by students and professionals on geological, paleontological, archaeological, botanical, cultural, economic and tourism topics.

State of conservation
PPF presents a regular state of conservation. Some deteriorated areas prevent the observation of geological characteristics (landslides). Some information panels are partially deteriorated.

Observation conditions
The observation of several silicified trunks of Araucariaceas and Metapodocarpoxylon specimens, marine invertebrate fossils of the phylum Mollusca of the pelecypods class and cephalopod (ammonoids) possible. The fossilized flora corresponds to the subphylum of the mid-Mesozoic gymnosperms of the Zamites, Dioonites, Nilssonia, Otozamites, Podozamites, Carpites, and other genera. It is also a dry-tropical forest ecosystem that preserves species (fauna and flora) existing today.

Rarity
The petrified trunks of Puyango represent one of the largest collections of petrified wood in Ecuador and probably in the world. The site has unique characteristics from the Cretaceous Period.

Geological diversity
The paleontological aspect stands out as the main geological interest, followed by the stratigraphic, sedimentological, structural and geological history. Secondary features are the historical/archaeological, biodiversity, cultural and landscape. There is a camping area less than 500 m from the forest.

Socioeconomic environment
The most common economic activities are the short cycle crops sowing and coffee, cattle and pig raising.

LIG size
Area of 2.6 ha. with 17 LIGs.
Vulnerability to plunder A paleontological site of great value, with numerous specimens and easy plunder.

Natural threats
Possible landslides, flooding of rivers, weakening of the soil and climatic variations due to severe droughts. The results of the applied evaluation of the IELIG methodology are represented in Table 4, noting that there are four LIGs with Geological Interest (IG) "Very High", nine of interest "High" and four "Medium", reflecting the great relevance of the Puyango Petrified Forest. The Global Protection Priority (PPG) values are also shown, finding most of the LIGs with the rating of "Medium-low".
The fossilized trunks resulted from the fossilization process, especially petrification by replacing organic matter such as cellulose and limenine with silica [33,35]. The paleontological importance with the highest concentration of logs has been found in the old Puyango-Alamor highway and El Chirimoyo, El Limón, and Cochurco streams, where specimens of logs of up to 26 m long by 2.2 m in diameter have been located (Figure 9). The fossilized trunks resulted from the fossilization process, especially petrification by replacing organic matter such as cellulose and limenine with silica [33,35]. The paleontological importance with the highest concentration of logs has been found in the old Puyango-Alamor highway and El Chirimoyo, El Limón, and Cochurco streams, where specimens of logs of up to 26 m long by 2.2 m in diameter have been located (Figure 9). From the point of view of the conservation of LIG, it is necessary to determine the susceptibility of degradation. This analysis is performed through the fragility and natural threats components. Hence, mitigation actions can be taken to reduce as far as possible the vulnerability of the geosite and the damage caused by an event and anthropic threats identified in the sector. The data obtained as a result of the implementation of Equations (6)-(10) were presented in Table 4. With this values, Protection priorities "Medium-low" were identified for each of the protection priority parameters  From the point of view of the conservation of LIG, it is necessary to determine the susceptibility of degradation. This analysis is performed through the fragility and natural threats components. Hence, mitigation actions can be taken to reduce as far as possible the vulnerability of the geosite and the damage caused by an event and anthropic threats identified in the sector. The data obtained as a result of the implementation of Equations (6)-(10) were presented in Table 4. With this values, Protection priorities "Medium-low" were identified for each of the protection priority parameters SPP, DPP, TPP and PP, which depend on the value calculated in the LIG Degradation Susceptibility (SD), this parameter is calculated independently of the others. The Figure 10 shows the sections of SPP, DPP and TPP with a global Protection Priority (PP) "Medium-low", except for two LIGs with a PP "High".
Sustainability 2020, 12, x FOR PEER REVIEW 18 of 24 SPP, DPP, TPP and PP, which depend on the value calculated in the LIG Degradation Susceptibility (SD), this parameter is calculated independently of the others. The Figure 10 shows the sections of SPP, DPP and TPP with a global Protection Priority (PP) "Medium-low", except for two LIGs with a PP "High".  Table 5 illustrates the SDTPI-ASC methodology.   Table 5 illustrates the SDTPI-ASC methodology.

Strategies
The results obtained through a SWOT analysis, which required extensive geological-paleontological fieldwork with experts and people from the community, are presented in Table 6. The authors took the Sustainable Development Goals (SDGs) into account to obtain strategies in terms of sustainable geotourism.

Discussion
The results obtained based on the IELIG's methodology provided data for both a quantitative and qualitative analysis, where the experts in geological, paleontological and archaeological sciences highlighted the forest's value as a unique example of the Cretaceous Period at a national level, which requires the recovery and preservation of its importance of the PPF as an Ecuadorian unique example of the Cretaceous Period, which requires the recovery and conservation of its heritage for sustainable development [37]. Additionally, the analysis suggested that the geotourism alternative supports the "Puyango" Geopark project. Experts have considered a referential assessment from 17 LIGs taken in the forest which on average are described as "below average" accessibility, "poor" sensibility and a "below average" conservations state that supports the usage of strategies to enhance the development of this area destinated for the geotourism as a pedagogical tool; it also promotes the restitution and improvement of geological and paleontological informative panels. Thus, it is essential to incorporate a web page to strengthen and increase the influx of tourists in the area, where the site is scientific and cultural information is disseminated nationally and internationally and to keep a record of annual visits.
The methodological study allows considering the PPF as a Geological Interest Place (LIG, acronym in Spanish) for the geological, paleontological, historical and cultural environment that surrounds it. The results evidenced to "Very high" geological interest in the LIGs "PPF Touristic trail", "Sábalos stream", "El Limón stream" and "PPF Interpretation Center"; "High" geological interest in "Cochurco stream", "Chirimoyo stream", "El Guineo stream", "Gringo Beach", "Las Concreciones stream", "Quemazón stream", "Tunima stream", "El Tigre stream" and "Playón Las Pailas" highlighting the paleontology of the place. The LIG Protection Priority (PP) scores classified as "Medium-low" in most LIGs; this is because the Puyango Petrified Forest (PPF) is a protected natural reserve of public administration, which gives it the competence and authority to management and protection policies. The LIGs to "PPF Touristic trail" and "PPF Interpretation Center" have a "High" rating of Protection Priority since they have a high influx of national and international visitors [17]. In the assessment, vulnerability to plunder also responded to the anthropic threat caused directly by collectors as the paleontological appeal is an intrinsic characteristic of the geosite. Therefore, knowing its PP fosters the adoption of measures for the conservation of the LIG [38,39].
Despite having high values in the geological-paleontological interest, it is necessary to monitor PPF, implement the proposed strategies and analyze its tourist development since it has 13,000 visitors per year, 70% are domestic tourists and 30% foreign [40]. Furthermore, the present study identifies shortcomings in terms of the infrastructure, as the place demands services for tourists such as accommodation, restaurants, a health care center and internet access and media communication. Nevertheless, PPF, with just 2659 hectares, has great potential compared to other forests with a large concentration of petrified wood such as the Jaramillo Petrified Forest National Park in Santa Cruz-Argentina of the Middle-Upper Jurassic Period [41]. The latter has 15,000 hectares and an average of 4800 tourists a year. Another case is the Petrified Forest National Park in Arizona, United States, of the Triassic Period, that includes more than 20,000 ha and around 5800 visitors per year [42,43].
Therefore, the results obtained in this study were satisfactory and provided necessary information to evaluate possible threats that affect the forest and its heritage in a natural environment and to boost the execution and implementation of scientific and territorial ordering in projects according to the population's capacity and the reality of the site [44,45].

Conclusions
The assessment of the methodology of the Spanish Inventory of Places of Geological Interest (IELIG, acronym in Spanish) carried out on seventeen different stations in the Puyango Petrified Forest, proved that it is a Place of Geological Interest (LIG, acronym in Spanish). Thus, PPF is in the categories of Very high and High interest in the scientific, tourist and educational sectors, for its great potential and geological relevance to promote geotouristic development.
The geodiversity of the forest is the main strength of the area, since it is considered a geological-paleontological heritage site, for purposes of touristic interpretation. PPF is one of the few sites in the world where you can analyze the paleontological aspects of the prehistoric flora and relate it to the current plant landscape. These characteristics make PPF an icon of geotourism in the sector. Hence, the proposed methodology SDTPI-ASC assessed the 17 LIGs in a preliminary stage and gave PPF a great value as a place of geological-paleontological heritage. Moreover, this analysis is a significant contribution to academia and its application facilitates the recognition of LIGs. Thus, the geopark project generates an alternative for the scientific, cultural and economic development of the population through a territorial order that addresses the 2030 Agenda and contains 17 Sustainable Development Goals (SDGs).
The importance of anthropogenic threats (deforestation, overgrazing, sample collection, burning of vegetation for new land and planting) and natural threats (landslides, river floods, severe droughts) faced by the geosites urge the protection and conservation of the LIGs. Therefore, strategies will substantially improve environmental, geological and paleontological conservation, as well as community participation and dissemination in the short and long term.
Finally, the development of bilateral relations with the neighboring country Peru will stabilize the intra-border situation and encourage Peruvian tourism to the PPF area. In addition, it will promote relations with international organizations interested in supporting the proposal for the sustainable conservation and resource management of the Puyango geopark project.  Figure S1: Macrofossils, Figure S2: Macrofossils, Figure S3: Microfossils, Figure S4: Microfossils.