tulisan – Page 11 – EARTH,SPACE & BEYOND

UNDERSTANDING OUR PLANET Q/A #2- Why doesn’t Earth keep getting larger if the rocks is continually created?

January 9, 2017March 17, 2017 by S.T. PradopoNo Comments

UNDERSTANDING OUR PLANET Q/A #2- Why doesn’t Earth keep getting larger if the rocks is continually created? - The concept of rock creation is similar as a cycle. The rocks that are formed on the outside of the earth come from the inside of the earth. Therefore, when rocks are formed on the outside of the earth, they leave empty spaces inside the earth. In reality, the "empty space inside" that I mentioned could be very small and is not deep in the earth's crust. Rocks are formed from lava (igneous rocks) or from part of the earth's crust (sedimentary rocks).Rocks are created at rift zones in the crust--they are also plowed into the mantle at subduction zones and melt.They don't add any weight to the earth because when the weight of the rocks is added to the weight of the rest of the earth, the total weight is the same as it was before the rocks were formed. Generally saying,...

UNDERSTANDING OUR PLANET Q/A #1- Why some parts of the lower mantle hotter than other parts?

January 8, 2017March 17, 2017 by S.T. PradopoNo Comments

UNDERSTANDING OUR PLANET Q/A #1- Why some parts of the lower mantle hotter than other parts? - First of all, the earth temperature is higher proportionally direct according to the pressure. This explains why the core is hotter than the lower mantle and the lower mantle is hotter than the upper mantle. The major factor causing heat beneath the earth is fusion reactions in the core. This reaction is involving some radioactive element such as uranium (U), thorium (Th), potassium (K). In subduction zone crustal material goes down deep into the mantle. It is assumed that the subducted crustal materials will be uniformly distributed in the whole mantle. Yet, based on many studies, there are geophyscial as well as geochemical evidence that some of these crustal material can go as deep as core-mantle boundary. Later on, the experts found particular zones where some of these crustal materials get concentrated. As mentioned before, these crustal materials are strongly enriched in heat producing...

Science, Philosophy, and Physical Geography by Robert Inkpen (Chapter 1. Ideas, Change and Stability in Physical Geography)

January 7, 2017March 9, 2017 by S.T. PradopoNo Comments

Bab 1. Pemikiran, Perubahan dan Stabilitas dalam Konteks Keilmuan Geografi Fisik Karya Terjemahan : Science, Philosophy, and Physical Geography by Robert Inkpen. Disclaimer : Buku "Science, Philosophy, dan Physical Geography" oleh Robert Inkpen diterjemahkan oleh S.T Pradopo dalam rangka tugas mata kuliah Filsafat Ilmu Pengetahuan Program S3 Ilmu Geografi. Tidak digunakan untuk kepentingan komersial. Harap selalu mencantumkan pengarang dan sumber referensi apabila ada pihak-pihak yang ingin menggunakan. Terimakasih. Ringkasan Ide dalam geografi fisik bergerak dinamis dalam ruang dan waktu. Perkembangan pengertian tentang realitas dapat mengikuti satu dari tiga model : progresif, paradigma atau program riset. Representasi dunia yang lebih baik dan progresif didapatkan dengan membangun sesuatu berdasarkan kesuksesan dari peneliti terdahulu dalam model pertama. Pengetahuan bersifat kumulatif dan menuju pengetahuan absolut atas realita sebagaimana realita itu sendiri. Paradigma berfokus pada sekelompok peneliti yang meneliti ide spesifik tentang sebuah realitas. Pilihan paradigma lebih mendekati sebuah tekanan sosial seperti halnya tentang logika, pilihan yang objektif. Bukanlah sebuah keniscayaan bahwa pengetahuan diturunkan dari suatu paradigma memberikan sebuah representasi...

SIMPLE MODEL FOR TSUNAMI HAZARDS ESTIMATION

January 6, 2017March 17, 2017 by S.T. PradopoNo Comments

SIMPLE MODEL FOR TSUNAMI HAZARDS ESTIMATION - CASE STUDY : BANTUL REGENCY, YOGYAKARTA PROVINCE - A tsunami (pronounced sue-nahm-ee) is a series of huge waves that can cause great devastation and loss of life when they strike a coast.Tsunamis are caused by an underwater earthquake, a volcanic eruption, an sub-marine rockslide, or, more rarely, by an asteroid or meteoroid crashing into in the water from space. Most tsunamis are caused by underwater earthquakes, but not all underwater earthquakes cause tsunamis - an earthquake has to be over about magnitude 6.75 on the Richter scale for it to cause a tsunami. About 90 percent of all tsunamis occur in the Pacific Ocean The word tsunami comes from the Japanese word meaning "harbor wave." Tsunamis are sometimes incorrectly called "tidal waves" -- tsunamis are not caused by the tides (tides are caused by the gravitational force of the moon on the sea). Regular waves are caused by the wind. A tsunami starts when a huge...

HOW TO ESTIMATE LANDSLIDE HAZARDS USING SIMPLE MODEL?

January 6, 2017March 17, 2017 by S.T. PradopoNo Comments

HOW TO ESTIMATE LANDSLIDE HAZARDS USING SIMPLE MODEL? CASE STUDY OF BANTUL REGENCY, YOGYAKARTA PROVINCE A landslide or landslip is a geological phenomenon which includes a wide range of ground movement, such as rock falls, deep failure of slopes and shallow debris flows, which can occur in offshore, coastal and onshore environments. Although the action of gravity is the primary driving force for a landslide to occur, there are other contributing factors affecting the original slope stability. Typically, pre-conditional factors build up specific sub-surface conditions that make the area/slope prone to failure, whereas the actual landslide often requires a trigger before being released. Landslides occur when the stability of a slope changes from a stable to an unstable condition. A change in the stability of a slope can be caused by a number of factors, acting together or alone. Natural causes of landslides include: groundwater (porewater) pressure acting to destabilize the slope loss or absence of vertical vegetative structure, soil nutrients, and soil...