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Abstract The objective of this research was to determine seismic events latitude and longitude using support vector machines (SVMs) and seismic records from “El Rosal” station, which is located 40 kilometers northwest of Bogotá, Colombia. A total of 504 SVMs models were tested to determine latitude and 504 models for longitude, with various combinations of complexity factor and kernel function exponent, applied to earthquakes of 2, 2.5, 3 and 3.5 ML in time windows of 15 , 10 and 5 seconds. The best results showed errors of 40 kilometers for latitude and 30 kilometers for longitude, with respect to the place where the earthquakes were generated. These outcomes might be improved by applying additional descriptors during SVMs training stages, such descriptors can be related to Fourier frequency spectra, predominant period and wavelet transform coefficients.

The purpose of this research is to apply a new approach to make a fast determination of earthquake depth using seismic records of the “El Rosal” station, near to the city of Bogota – Colombia, by applying support vector machine regression (SVMR). The algorithm was trained with descriptors obtained from time signals of 863 seismic events acquired between January 1998 and October 2008; only earthquakes with magnitude ≥ 2 were contemplated, filtering its signals to remove diverse kind of noises not related to earth tremors. During training stages of SVMR several combinations of kernel function exponent and complexity factor were considered for time signals of 5, 10 and 15 seconds along with earthquake magnitudes of 2.0, 2.5, 3.0 and 3.5 (Ml). The best classification of SVMR was obtained using time signals of 15 seconds and earthquake magnitudes of 3.5 with kernel exponent of 10 and complexity factor of 2, showing accuracy of 0.6 ± 16.5 kilometers, which is good enough to be used in an early warning system for the city of Bogota. It is recommended to provide this model with a previous phase of deep-shallow classification.

A Support Vector Machine Regression (SVMR) algorithm was applied to calculate the epicenter distance using a ten seconds signal, after primary waves arrive at a seismological station near to Bogota - Colombia. This algorithm was tested with 863 records of earthquakes, where the input parameters were an exponential function of waveform envelope estimated by least squares and maximum value of recorded waveforms for each component of the seismic station. Cross validation was applied to normalized polynomial kernel functions, obtaining mean absolute error for different exponents and complexity parameters. The epicenter distance was estimated with 10.3 kilometers of absolute error, improving the results previously obtained for this hypocentral parameter. The proposed algorithm is easy to implement in hardware and can be employed directly in the field, generating fast decisions at seismological control centers increasing the possibilities of effective reactions.

The objective of this research is to apply a new approach to estimate arrival azimuth of seismic events using seismological records of the “El Rosal” station, near to the city of Bogota – Colombia, by applying support vector machines (SVMs). The algorithm was trained with time signal descriptors of 863 seismic events acquired from January 1998 to October 2008; considering only events with magnitude ≥ 2 ML. The earthquake signals were filtered in order to remove diverse kind of low and high frequency noise not related to such events. During training stages of SVMs, several combinations of kernel function exponent and complexity factor were applied to time signals of 5, 10 and 15 seconds along with earthquake magnitudes of 2.0, 2.5, 3.0 and 3.5 ML. The best classification of SVMs was obtained using time signals of 5 seconds and earthquake magnitudes greater than 3.0 ML with kernel exponent of 10 and complexity factor of 2, showing accuracy of 45.4 degrees. This research is an improvement of previous works related to earthquake arrival azimuth determination from data of one single seismic station employing machine learning techniques.

The present research work examines three aspects of great importance for the future supply of oil and gas in Colombia. 1) The geographic and stratigraphic distribution of hydrocarbon resources for use in estimations of the contribution of different field sizes to the total supply of oil and gas in Colombia. 2) The current state of the hydrocarbon reserves in Colombia and factors that influence their increase or decrease; statistical tools are used to calculate the volume of hydrocarbons that may be found in the future. 3) The observed decline of hydrocarbon production in Colombia, which is used to estimate the amount of resources that may be extracted in the future once peak production has been reached. Based on these three aspects, we constructed different scenarios to forecast the potential production of oil and gas in Colombia. In addition, we calculated the amount of hydrocarbon reserves in these scenarios. Resumen El presente trabajo resume tres aspectos considerados de gran importancia para el futuro suministro de petróleo y gas en Colombia. Estos son: 1) La distribución ¿geográfica y estratigráfica? de los recursos hidrocarburiferos como herramienta para conocer la contribución de los diferentes tamaños de campo a la producción total de hidrocarburos en Colombia; 2) El estado actual de las reservas de hidrocarburos en Colombia y los factores que inciden en el incremento o disminución de las reservas, que son dos asuntos temas que inciden en el futuro suministro de estos recursos. Al respecto, por medio de herramientas estadísticas se calcula el volumen de hidrocarburo que puede ser encontrado en el futuro. 3) Las tasas de declinación en la producción de hidrocarburos observados observadas en Colombia, permiten modelar los recursos que pueden ser recuperados en el futuro una vez alcanzados los picos de producción. Bajo esta hipótesis, se construyen diferentes escenarios que resumen pronostican la posible producción de petróleo y gas en Colombia para los próximos años, además se calculan las reservas de hidrocarburos para los mismos escenarios.

It's time to present our second volume of 2017. The result of a great effort to put into your hands some works of the best quality. With this selection of articles, an invitation to the Colombian Geology Congress. As every two years, in a city strategically picked up to show the best of the Colombian and Latinamerican Geology, the Sociedad Colombiana de Geologia entity (Colombian Geology Society) presents the XVI Congress of Geology and the third Explorers Symposium. The venue is Santa Marta, a touristic city in the Caribbean. Register for technical courses and field visits are still open. The event is scheduled August 28 until September 1, 2017. Recent months, it has been confirmed in Colombia a gas reservoir with at least 520 meters of netgross at the Kronos well, which suggests a substantial increase in the gas reserves of the country. Sure, a subject to be analyzed during the Congress. The discovery, which left the first results in 2015, is proved in a depth of 4,795 meters, including a 1,835-meter water table. The state-managed company Ecopetrol holds a 50% share in this block, according to news releases by them, as the 50% remaining is of Anadarko, an operator company. These figures are on the same way that the energy reserves around the world, where new techniques and exploration have reached peaks to cover the current demand for oil and related products for decades. This growth of reserves in the world goes hand in hand with the investment. Ecopetrol, for example, announced the increase of its exploration budget this year to US$ 650 million with the final purpose of intensifying the search for new hydrocarbon reserves. But mining in the Earth would be not the unique perspective to analyze. Goldman Sachs wrote a recent note explaining that “space mining could be more realistic than perceived,” according to an interesting article published by The Washington Post on 28 April 2017. The report analyzes the possibilities and bets the mining out of the Earth is a decade away. For the next year, the NASA plans to vacuum materials from a 2,000-foot-wide asteroid called Bennu; sure it would be the cornerstone. Thanks for your attention to this number of the Earth Sciences Research Journal and the little reflections proposed in this letter. With the best regards, Carlos Alberto Vargas Jimenez Editor in chief