There Change the design of the studying process in University during the covid-19 pandemic from face to face to online learning needs some tools to support it. Some tools coming with their own advantages and disadvantages. One of them is Zoom. It becoming tools liked by many lecturers and college students because easy installation process and complete features although it is not free and easy to hack. Nevertheless, internet access is still becoming a big problem in online learning. A mix between two tools of online learning is one of the solutions, for example, zoom and google classroom application. Zoom is used for virtual communication in online learning but it does not provide features for sending the assignment. Otherwise, google classroom provides features to send and receipt some assignments, and it can save the quote on the internet. Both of them will complete each other to support all needs in online learning.

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In July 2018, Lombok Island in Indonesia shaked by earthquake of Flores Fault. The earthquake is felt in surounding Lombok like Bali. There are two major earthquake source in Lombok, they are Flores fault in the north, and subduction zone in the south. There are more than 300 fatalities of human, and more than 270.000 refugees. The government of Indonesia established that Lombok Earthquake was a national disaster. This research is aimed to describe how the subduction zone around Lombok both it come two major of earthquake source and to answer the rumor is the earthquake affect Rinjani vulcano in Lombok activity or not.

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The subduction zone occurs in Java Island analyzed based on data of tectonic earthquake. Earthquake data used is P wave velocity accessed from the ISC website from 1900-2013 years located along the Java Island. ISC is an organization that provides a variety of data tectonic earthquakes around the world, but the data used is the data before relocation. Relocation needs to reposition the hypocenter, so it can result a new position based on geological model. The relocation is using Jacobian's matrix and AK135 velocity model of P wave in each depth. The tomography process using FMTOMO software from result of new hypocenter represent the subsurface condition at a depth of 0-700 km. The result of hypocenter relocation is shifted horizontally to the southeast while vertically relatively shallow. The results obtained from the tomographic analysis of north-south section show the response of the velocity wave where high value shown in blue color as subduction zone and low value shown red color under volcanic as the partial melting. Tomographic 3D visualization displayed by Voxler software shows the different subduction in Java Island. Result of 3D analysis indicate that the subduction in West Java until Central Java relatively sloping than subduction in East Java.

One of important thing in locating hypocenter process is determine P and S arrival time of the seismogram. Beside that, frequency analysis by FFT method is needed to know the character of the seismogram, like dominant frequency. For further analysis, FFT method can be a good tools in determine P and S wave arrival time in the spectogram form. This process is called automatic picking.