Bench stability in open pit mines : a methodology for jointed rock masses
The methods used to determine the overall gradients of the slopes in open pit workings aim to sufficiently eliminate all risk of failure on a scale comparable wich the pit walls. For this the slopes musc be made shallow gradual and reinforcing measures must generally be applied. Most often these consist of ensuring the drainage of the slopes and in limiting the effects of blasting (reinforcement is generally too costly in the case of very high slopes and deep planes of failure).
Generating a blocky rock mass
Abstract A block generator has been developed to reconstruct the three-dimensional block structure around excavations in rock. The blocky rock mass defined by the generator is an essential input to study of the stability of the jointed rock masses in the vicinity of excavations, using either single block stability analysis techniques, or block model codes. The generation method enables us to include knowledge of the tectonic history of the rock mass in order to make maximum use of the usually limited data on the fracture sets. A computer language BGL (Block Generation Language) has been developed to facilitate application of the method. The main features of BGL are outlined and a tutorial example is presented. Finally, the problem of graphically displaying the joint systems of three-dimensional blocky rock masses is discussed, and a novel graphical display method is presented.
Seismic and Sequence Analysis of Middle to Late Miocene Deposits of Northeast Java Basin
DOI: 10.17014/ijog.2.2.101- 110 This study is focused on Middle to Late Miocene sediments. As depicted in the regional geology of Indonesia, the area of study is part of Northeast Java Basin. There are three phases of tectonism in the basin: extensional tectonics at Eocene-Oligocene time, compressional tectonics at Middle Miocene, and compressional tectonics at Miocene-Pliocene time. The result of the study shows three sequences were developing during Middle to Late Miocene, those are: (1) Middle Miocene sequence-1 (MM-1 sequence) consisting of a Lowstand Tract System deposition in Middle Miocene-1 (LST MM-1), Transgressive System Tract deposition in Middle Miocene-1 (TST MM-1), and Highstand System Tract deposition in Middle Miocene-1 (HST MT-2); (2) Middle Miocene sequence-2 (MT-2 sequence), comprising Transgressive System Tract Middle Miocene-1 (TST MM-2), and Highstand System Tract deposition in Middle Miocene-1 (HST MM-2); (3) Late Miocene sequence-1 (LM-1 sequence), composed of a Lowstand Tract System deposition in Late Miocene -1 (LST LM-1) and a Transgressive System Tract deposition in Late Miocene-1 (TST LM-1).