׉?4ׁB!בCט{u׉׉ 7cassandra://pgJHLEezW516GNvRVR-w5QlJJyKjVKXWrZ2uJfcWNOs\o` ׉ 7cassandra://d3mCMOUf5QL14E673XV39slCKV66nZW2S368G1_TjEs-G`S׉ 7cassandra://AYT27v_ap-k-D5dq8_jlXtgRcmAbtHwcQpS5Y5xiB-g`̵׉ 7cassandra://xFCp_itmsjrD5jwm_B4M6evh5V8CIj1oaJDFM3prrbo=L͠[sט{u׈+E ׈E[r׉E4Sub-bottom specialist Geophysical solution provider ׉ 7cassandra://AYT27v_ap-k-D5dq8_jlXtgRcmAbtHwcQpS5Y5xiB-g`̵[r[r{בCט{u׉׉ 7cassandra://mlM8J8lIMMQjUm4xQ9CVuBbfpuqPMtvvKdAKZx55HyY` ׉ 7cassandra://euU0xfdvoiJXBlF8DCTDK16V5oRn120sy1xAYzdXOSI `S׉ 7cassandra://PsSDQuBV2B0nUHNv-ElRW6oqdidX43rqbgB8p_oAa9U`̵׉ 7cassandra://Sg8999fPKIz0_jno-pqYfvG9N6DqoWIt7QwIG_v5Em8 b͠[sט{u׉׉ 7cassandra://-5FDE1sq_NYjS7HXx_GkbzAtl9pFF_MpJAQaLt732MM` ׉ 7cassandra://7YfWCdCprVzg6lmfaGauFLONcvL-bIeMNb1hsu-6YKU3`S׉ 7cassandra://Pxo5nzKS1isWRmzMOBPw5afmfYD5VZtnzkmipOX_f7I`̵׉ 7cassandra://uFYaBPUfnZiG7rm_J9REQTNxP2WgSX3XtPSyXYzkEJct ͠[sנ[soE9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉Ewww.stema-systems.nl ׉ 7cassandra://PsSDQuBV2B0nUHNv-ElRW6oqdidX43rqbgB8p_oAa9U`̵[r׉EStema Systems Stema Systems has since 1986 been delivering specialized services and equipment to the hydrographical survey industry, we have done so while keeping in mind the strenuous and strict requirements that our customers work with and have come to expect of Stema. Stema Systems has a history of providing hydrographic equipment to the survey, dredging industries as well as some well renowned educational institutions. The reason that Stema Systems clients chose our service and products over and over again is for our in-depth knowledge, our insight into their needs and our willingness to go over and beyond to ensure that the client achieves the goal that they have set themselves. As part of these investigations Stema Systems provided active assistance in acoustical investigation of the seabed with Stema Systems purposely developed Silas Software Suite together with sampling and rheological analysis of (semi)-fl uid sediments. Given the ever changing environment that Stema Systems operates in, it is continuously improving and developing new products, these range from complete survey boats to the detection of sub-sea cables, our philosophy is to work with our customers to achieve the needed solutions that will enable them to perform at an optimal level. In 2016 Stema developed a cable detection system that would enable the location of cables and object buried in the seabed, based on the EBP system in combination with the Silas Software Suite, adding this capability into the Stema portfolio, providing our clients with the possibility to monitor depth of burial of cables for installation and also maintenance projects. Stema Systems welcomes all questions and opportunities to think with and work with solution providers and to this end we would welcome you to contact us for any and all questions, enquiries or potential projects that you may have. With regards, Pepijn P. Peter managing director www.stema-systems.nl 3 ׉ 7cassandra://Pxo5nzKS1isWRmzMOBPw5afmfYD5VZtnzkmipOX_f7I`̵[r[r{בCט{u׉׉ 7cassandra://l2hrtthRirIsCZ2emLWo6UjVm3wX7OiyOPluINvzZDI` ׉ 7cassandra://luUlxAvvNTf7voOLgV4-dc8y1wG-T3RGVzNt1twFHBk8_`S׉ 7cassandra://RzjsXm74LXG3UW8VS_6kp-0XhAWW_iIfaESCZi1_MzI)`̵׉ 7cassandra://0LXiI_A0U2dN4tIYzMH0FSBGq5SWvUT9FT28t_mMl0Ir͠[sט{u׉׉ 7cassandra://9uHFHOhVhxMKs3E6U0TuuDiX4bjw5P3lf_Vyy5GNfyQR+` ׉ 7cassandra://CdCfkVLAWmdAf77Rd3KNQNd8OOvk4TnqEe4DF2Xxnk8.`S׉ 7cassandra://OUOVdvFSgLuLQKLxRrug5SAxcL_bFGU_8mUgKZh0Q-U.`̵׉ 7cassandra://OblIlO1cWfpFl7Xwqa_mELORywllotwc8o-9M3YyTaU< /͠[sנ[swH9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉ENSilas Silas is a complete data acquisition, processing and interpretation software suite, that covers a wide range of tasks. The Silas Software Suite has been developed to allow you to obtain the best quality data and easy access to multiple data types to best evaluate the subsurface conditions. It is compatible with multiple sources and can process sub-bottom profi lers, boomers, sparkers, parametric and chirp systems. The system covers the range from deep penetration to ultra-high resolution. Whether you look for general sub-surface geology, cables, pipelines and other objects or fl uid mud surveys. For sub bottom classifi cation and interpretation the Silas Software Suite can easily integrate borehole and map data into the data set, providing the information that is sought allowing for detailed interpretation. www.stema-systems.nl ׉ 7cassandra://RzjsXm74LXG3UW8VS_6kp-0XhAWW_iIfaESCZi1_MzI)`̵[r׉EOKey OEM OEM elements input data hardware colour related to the product sheet 5 ׉ 7cassandra://OUOVdvFSgLuLQKLxRrug5SAxcL_bFGU_8mUgKZh0Q-U.`̵[r[r{בCט{u׉׉ 7cassandra://cLF_80HJkBeog2Sdo2g4kCaxur9TPXrr9KXFBKIoNlY3]` ׉ 7cassandra://b6-1XF_S9lVwl1SZPpyvH6Y9EEhgwnabzxGPrN9YLowK_`S׉ 7cassandra://H3KdW4sLErUmbHPueKJ5-rbGTGT4fTvC1XJRaQYU2lsP`̵׉ 7cassandra://MsMuxeo_2KKRoKCldy4b7XBoeeK9YO5Eh93h7Eb0UAA :c͠[sט{u׉׉ 7cassandra://WGw7fM9OuM4MYQt0KhmjnOGE7MdcrLiFC14qsz3jX1Q` ׉ 7cassandra://qHGkoWHq47NHptxwgGRO6ghEoBF-rh8Bol1Dm3PqgiED`S׉ 7cassandra://Ww_4W_NMpn6q2kbJ4AH36v5s6Q3j-0sjJThYIM7FJVk`̵׉ 7cassandra://m_qXJZOjVFeuEI1_dJ8Q510LNUIXEFrK8ASwsF2zG8k͠[sנ[s"wH9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉ESilas Seismic acquisition and processing software suite Deliverables • Nautical Depth • Site investigation / Layer detection • Object / Cable / Pipeline detection Silas is a complete data acquisition, processing and interpretation software suite, that covers a wide range of tasks. The Silas software package has been developed to allow you to obtain the best quality data and easy access to multiple data types to best evaluate the subsurface conditions. It is compatible with multiple sources and can process the full-wave signal from sub-bottom profi lers, boomers, sparkers, parametric and chirp systems. The system covers the range from deep penetration to ultra-high resolution. Whether you look for general sub-surface geology, cables, pipelines and other objects or fl uid mud surveys. For sub bottom classifi cation and interpretation the Silas Software Suite can easily integrate borehole and map data into the data set, providing the information that is sought allowing for detailed interpretation. Silas recording with integrated borehole data. Pipeline detections with Silas Object detection. Key features • Import of profi les for accurate seismic interpretation • Ultrahigh resolution (combination with USB-A/D) • Seg Y Import - Export Related products EBP RheoTune Object detection Mapview of Silas profi les with multibeam bathymetry. Geo Consulting Sales & rental www.stema-systems.nl ׉ 7cassandra://H3KdW4sLErUmbHPueKJ5-rbGTGT4fTvC1XJRaQYU2lsP`̵[r׉E cSilas Seismic acquisition and processing software suite Specifications Acquisition Digital high resolution seismic acquisition. Supports USB-A/D card and UDP inputs/outputs. Real-time data and single trace monitoring, including real-time output of depth values of bottom track and a bottomlayer: hard bottom or iso-density level (requires calibration). Processing Silas Density Pro License Digital seismic processing package that enables the user to identify, analysis and interpret the geological features found in the sea bottom. With features such as: • Layer tracing • Position and tide corrections • Navigation view • Cross-points • Batch fi ltering • Signal correction • Borehole import/export • Density calibration of seismic data for nautical depth management • Fluid mud migration studies • Predictive multiple reduction • Seismic parameter assessment • Sub-bottom classifi cation module Matrix import Silas module: displays multibeam or gridded data loading in seismic records to check against or match with height data. Frequency fi ltering Silas advanced signal processing modules for S/N enhancement providing a wide range of frequency fi lters. Deconvolution Silas advanced signal processing modules for S/N enhancement providing spiking deconvolution tools. Horizontal stacking and multiple suppression Silas advanced signal processing modules for S/N enhancement by suppression and enhancement techniques. Density calibration and calculation Tool to match acoustic data with in-situ density profi les. Calculation of synthetic density profi le per trace. Tool required for real time density mapping. Overlay borehole and geotechnical data Import and overlay of borehole data (BH, CPT, chemical tests, density, etc.) on seismic records. Subbottom material classifi cation Signal analysis and matching to material properties of subbottom layers: Impedance, absorption and velocity module. Density (red) and yield stress (blue) profi les in a fl uid mud layer recorded by the RheoTune, implemented in Silas. GeoTiff mapviewer Import of geotiff data (multibeam, sss, geological map etc) and presentation in plain view. Automated contact detection Contact recognition based on two quantifi able parameters which enable a more objective classifi cation of detected contacts. SEG Y import / export Silas module: reads and stores seismic data in various SEG Y-formats. 7 ׉ 7cassandra://Ww_4W_NMpn6q2kbJ4AH36v5s6Q3j-0sjJThYIM7FJVk`̵[r[r{בCט{u׉׉ 7cassandra://kEOh8sQymoWvmZLx-pH-kxyGHH6uLNjSUFe_zwAtmH8` ׉ 7cassandra://ITCThlESmpJxNH8Qv2oUL-uZL_4wQcJsL7YlJCFlwOI@Z`S׉ 7cassandra://0iwtJSRWan457U6hSj55rNtBRBY0n_TqcID6VWA3nGY`̵׉ 7cassandra://gtSZkw7nyNmtu2FZs49Ktrz7op7jsPEU4tblsNvguWc3͠[s#ט{u׉׉ 7cassandra://heKtW1rOQVYENQSmokBEj_ze_sF1SA6-LRCM8yVxnwoD` ׉ 7cassandra://eGO5pQEZqs3XILs2G39KWQaErJ1wenW6z4c-QIXmW1M3 `S׉ 7cassandra://GY1KPzZ8vXjo5HCTLRGRY700D7tViSNDREilNn_L6Sk+`̵׉ 7cassandra://WwTqtbUyd0HBDJpkUViCbEBv6v97oxnIN1t7OlsImwg͠[s$נ[s&wH9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉E\EBP Ultra-high resolution sub-bottom profi ling Deliverables • Ultra-high resolution sub-bottom profi ling • Cable detection • Fluid mud detection The EBP system has been developed to yield optimal results in the area of 3 – 33 kHz sub bottom acquisition range. It offers the choice of transducers dependant on requirement and processes this via its unique USB-A/D confi guration to ensure the highest resolution of your data. With the full digitalization of the signal the system enables full and quick import of the acquired data into the Silas Software Suite, ensuring the high resolution transmission of data for full processing. Silas profi le recorded with EBP system to identify top and bottom of fl uid mud layer. Stema EBP Sub-bottom Profi ler system. Choice of transducers will be recommended to fi t required result. Key features • Easy to deploy and operate • Multiple frequency range 3 - 33 kHz • Easy to integrate in survey setup Related products Silas Object detection Sales & rental Example of transducers used with EBP system to detect export and infi eld cables. www.stema-systems.nl ׉ 7cassandra://0iwtJSRWan457U6hSj55rNtBRBY0n_TqcID6VWA3nGY`̵[r׉EEBP Ultra-high resolution sub-bottom profi ling Specifications Frequency High band: 100 kHz - 1 MHz Low band: 3.5 kHz - 50 kHz Power Output High band: 900 W RMS at 200 kHz Output Low band: 2 RMS Input 110 or 220 V AC - 24 V DC, 120 W Interfaces 4xRS232 Ethernet interface Output Raw seismic wiggle (user select sampling rate) Digitized depth levels (echo-sounder pre-sets) Real-time density level (requires calibration) Transducer options • 3 – 7 kHz • 10 – 14 kHz • 24 / 33 kHz Vertical resolution • Depends on frequency and cycle selected • 24 kHz 1 cycle < 10 cm • 4 kHz 1 cycle < 40 cm Penetration • Depends on soil type and frequency • 24 kHz: clay / mud, typical 5 m • 4 kHz: clay / mud, typical 10 – 20 m • 4 kHz: sand, typical 5 m Peripheral equipment options • Boomer • Sparker • Bubblegun Data acquisition Display profi le and individual trace, external heave, colour control, position input, signal offset correction, auto-start (slave from Survey PC), real-time density computation Data processing Display profi le and individual trace, unlimited layer defi nition, auto-tracing, layer copying, swell fi lter, external heave/tide, sub bottom amplifi cation, navigation display, cross points and quick line select, targets, export layers to ascii or CAD, graphics export to html, bmp, jpeg Example of Silas sections with detected cable (left) and detected pipelines (right). 9 ׉ 7cassandra://GY1KPzZ8vXjo5HCTLRGRY700D7tViSNDREilNn_L6Sk+`̵[r[r{בCט{u׉׉ 7cassandra://b17OHOJbIXBWWRRYD24XlpMlTvFY_cXFlDsNhdBMxME` ׉ 7cassandra://woe3KH-s1ddwD14PAb6wLIrQ2HfNIlkSo9cSdsRuYvAIJ`S׉ 7cassandra://DZSWKrMuj0sOLK7NJ15Kd5d1RfhA0rm7yUGhmAmAdr0Y`̵׉ 7cassandra://cO4eWVAgkpBnYj10TPfxeGTHaOzUWS7fuCXPnxgD1-kU͠[s'ט{u׉׉ 7cassandra://6SUGM-mF7iXqjGcHYGa2g4pHb8Ea0j3WEh-oPf1TASU&` ׉ 7cassandra://bxMzC0g0hBYPh8nzMgrQUzPgjlsOKMzSLcA_rJ7NYfM2`S׉ 7cassandra://9cDkFzMEdjCBUZa6ZPsXamG2Re18a3GK4px1_JBTZVI"`̵׉ 7cassandra://JNvXhZ-_V-d8NzeXGJ9Qr1h2LGBzaptQhBZV1BxV_w4>͠[s(נ[s*wH9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉E\RheoTune Density and yield stress measurement Deliverables • • • • Density profiles • Nautical depth Properties of fluid mud Yield stress profi le Density profi les f fl Yield stress profile The RheoTune is a versatile system that provides both density as well as yield stress profi les of fl uid mud simultaneously. The fact that the RheoTune is pre-calibrated makes it easy and quick to deploy, enabling swift and accurate data acquisition. Running proprietary software for both acquisition and processing results in a detailed almost real time display of the profi le that can be imported into sub–bottom profi ling processing suites enabling a full and comprehensive picture of the fl uid mud and its characteristics. To increase productivity further an automated electrical winch or manual light weight winch with slip ring is available. The Tune system is optimized to integrate with the Silas Processing Software. Stema RheoTune in action. Both density and yield stress are measured in-situ without the need of fi eld calibration. RheoTune software displaying both density (left) and yield stress (right). Key features • Constant accurate results • Easy to deploy and operate • Pre-calibrated Related products Silas IntelliWinch Density and yield stress results of RheoTune plotted in a Silas record. Sales & rental HSP winch www.stema-systems.nl ׉ 7cassandra://DZSWKrMuj0sOLK7NJ15Kd5d1RfhA0rm7yUGhmAmAdr0Y`̵[r׉ERheoTune Density and yield stress measurement Specifications System RheoTune Output parameters Density, Yield stress, Viscosity Dry solids, Temperature, Depth (P) Material classifi cation Density Accuracy Resolution Range < 1% of density (Newtonian fl uid) 1 g/L 800 – 1500 g/L (semi fl uid materials with Bingham yield stress < 1 kPa) 1500 – 1800 g/L (with adapted calibration in semi fl uid materials) Yield stress (Bingham) Accuracy Resolution Range Ca. 5% of Yield stress 1 Pa 0 – 500 Pa Viscosity Accuracy Resolution Range * Viscosity is derived from density based on a roto visco laboratory test for site specifi c material. Temperature Accuracy Resolution Range Depth Accuracy Resolution Range Housing Probe Control box Dimensions Probe Transport case Weight Probe Transport Power Input Output Type Update rate The design of RheoTune is kept simple and robust. 2% FS 1 °C 0 – 60 °C 0.25% of depth 0.01 m 0 – 60 m Stainless steel (IP68, 250 m) Fork Plastic box (IP65) 75 cm with 15 cm 80 x 58 x 48 cm 15 kg (+9 kg weight optional) 35 kg (excl extra weight) 110 / 220 V AC, 35W UDP and Ethernet standard, Wi-Fi optional 20 Hz Depending on site calibration* 1 Pa s 0 – 600 Pa s 11 ׉ 7cassandra://9cDkFzMEdjCBUZa6ZPsXamG2Re18a3GK4px1_JBTZVI"`̵[r[r{בCט{u׉׉ 7cassandra://50NndzEzczRhmjfAs8lyfW7MyX3WEtQ9AebvUAcLmxE` ׉ 7cassandra://xtCGeAhZhz4jRgYgUAlhvVyuNpl-aCBVmD9oq_p-GekT+`S׉ 7cassandra://8_24ex47sc5NEiIT1M3mrf-57oZIuR_USikSizqo0TY`̵׉ 7cassandra://Ee3nqRveMjOTF8bywVbGVK8te9ODVw4C2jjQHmCj7M0͠[s+ט{u׉׉ 7cassandra://ectqxCHlQN5ENv4_lZSCJRy6ynBJL8Bzt73G3QmMmFcC` ׉ 7cassandra://RyqqXzBFz9IaXybb6LchPpg3fGLpxYukiUJlJEpUvyM8 `S׉ 7cassandra://k_v_L2LSQ96gPV0jmIgslrxPHugoWInKoIo4rUeZ2fY`̵׉ 7cassandra://YL8JkeBCKl54mtJDgyHd77EJ2DW0_XaZ3UNgSmH3CYg͠[s,נ[s.yc 9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉EObject detection Cables, pipelines and boulders Deliverables • Depth of burial surveys • Cable and pipeline mapping • Location of objects within the sea bed A combination of the Stema EBP system and the Silas Software Suite enables the user to perform high resolution object detection surveys. The Silas Object detection module then allows an automated contact recognition, identifying objects such as cables, pipelines and boulders. These objects can be detected with a success rate of 75% and higher both for objects and cables. The contact recognition consists of the automated determination of two quantifi able parameters which enable a more objective classifi cation of detected contacts. Besides the object contacts themselves, the sub-bottom data also shows the sub-bottom structures, including the cable trenches. The latest development of the Silas Software Suite provides the possibility to import multiple data sets for cross correlation and mapping of the objects in X, Y and Z coordinates. Example of Silas sections with detected cable (left) and detected pipelines (right). Topview of detected pipeline with multibeam overlay and cross-section of the same pipeline which clearly depicts depth of burial. Key features • Automated contact detection • Correlation with other data (MB, SSS, Magneto) • More objective classifi cation of detected contacts Cross-section of typical export cable, which can be detected sub-bottom with Silas cable detection. Related products Silas EBP Sales & rental www.stema-systems.nl ׉ 7cassandra://8_24ex47sc5NEiIT1M3mrf-57oZIuR_USikSizqo0TY`̵[r׉EObject detection Cables, pipelines and boulders Automated contact recognition The Stema Silas Object detection package enhances the high resolution data acquired from the EBP system by integrated processing techniques and applies an automated contact recognition technique. The contact recognition consists of the automated determination of two parameters: • Semblance of apex of hyperbola (top of contact) • Power of hyperbola These parameters are quality fi gures which also enable a more objective classifi cation of detected contacts. Plan view with track lines, contacts and multibeam data. Comparison of seismic boulder registration in regular Silas display (top) and seismic power display (bottom). The latter has been developed specifi cally to identify individual boulders sub-bottom. Objects detected: • Infi eld cables • Export cables • Oil pipelines • Gas pipelines • Water pipelines • Boulders for cable trenching • Wrecks The contact data and its parameters can be managed and inspected in several displays: • Plan view with Geotiffs • Contact display • Navigation View The Stema Silas Object detection package can be interfaced with DXF-fi les and contacts from other data sources such as: • Multibeam • SSS • Magnetometer • GPR This integration permits the user to present a full cable passport, with multiple data sources to illustrate the exact cable lay. 13 ׉ 7cassandra://k_v_L2LSQ96gPV0jmIgslrxPHugoWInKoIo4rUeZ2fY`̵[r[r{בCט{u׉׉ 7cassandra://afze0z4Fl-bnUUH5fZ3lCNYxg7sbjRRs_t-O5erPlI8` ׉ 7cassandra://y2Gyv3es-pZgXWgM8RuMLU5mYAAXJHzgUmRdq-u-hGwD`S׉ 7cassandra://ENIF__kBHleLOl-yUpCKy0fWH_nJszKUX8NTDMC7BOkL`̵׉ 7cassandra://09mPYrZsaM325iXuQYzEP8p1FkNZcEBsnqsr57PO0TY͠[s/ט{u׉׉ 7cassandra://ZzXBafi70wIYmDpCAxH1RSb2RZ9czycr4VR9SazjGcc:` ׉ 7cassandra://MigvnC04xcof4a-XVLQl3Xa_FkZvKYApdUpCzWcYX887`S׉ 7cassandra://SfvVDSQ3vmLbJzMHhUdbTQB7iThlYm8WKnT4vDtBLxA`̵׉ 7cassandra://HZ8MluSY1sBoi4NBmuxX4-hvo-t6q7iLUayqd7dLVYI(͠[s0נ[s2yc 9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉ESales & rental For all survey needs Deliverables • Hydrographic equipment • Geological analysis equipment • Processing software Stema Systems has been renting out equipment of the highest quality for the past many years, supporting the hydrographic and geological survey industries with equipment as well as its wide knowledge base, not only supplying equipment but also providing advice and installation assistance when needed. During this period of time Stema Systems has been able to assemble what it believes to be the best product range that suits its customers’ needs based on its own experience and requirements. Stema Systems can through its fl exible and its wide network of equipment suppliers provide specialist equipment not listed below for almost every water based survey need. Therefore please enquire if the equipment that you would require is not listed and Stema Systems will do its utmost to endeavour to locate it for you. Equipment Survey vessel Stema Systems plug & play survey boat 7.25 m Echosounders Multibeam • R2Sonic 20XX series • Teledyne T series • SeaBat series Soundvelocity sensors • AML SVS • AML SVP • • Selection of Stema suppliers. Valeport SVS Valeport SVP Side scanning sonars • Klein • EdgeTech ROV • Key features • Major suppliers portfolio • Large stock • Customizable packages • • • ye Falcon ROV Saab Sea-eye Falcon ROV McArtney Nexus MK IV MUX subsea and surface unit Subsea laers Subsea camerara sers exus MK IV MUX Subsea Lasers and surface unit www.stema-systems.nl ׉ 7cassandra://ENIF__kBHleLOl-yUpCKy0fWH_nJszKUX8NTDMC7BOkL`̵[s׉EiSales & rental For all survey needs Equipment USBL • Kongsberg • EvoLogics Laserscanner • Riegl • Faro Geotechnical (subbottom profi ling, HR seismics) • Stema Systems EBP • Low-frequency transducers • Teledyne Odom MK III • GeoMetrics boomer • GeoMetrics sparker • GSO negative sparker • Applied Acoustics boomer • Applied Acoustics sparker • Applied Acoustics streamer single channel • Applied Acoustics streamer multi channel Geotechnical (fl uid mud, nautical depth) • Stema Systems RheoTune • Stema Systems IntelliWinch Magnometers • Marine Magnetics • Geometrics gradiometer Motion / gyro sensors • • R2Sonic I2NS • ADCP • Rowe • TSSTeledyne TSS IXblue Phins / Octans / Rovins Teledyne GNSS positioning and heading • Stema Systems GNSS-982 • C-Nav • Ashtech • Hemisphere Crescent Software Packages • Stema Systems Silas Acquisition • Stema Systems Silas Processing • Stema Systems RheoTune • QPS Computer Hardware • Stema Systems USB A/D Card • Support (hourly rates) • • Industrial Silas PC incl. one LCD 22” Installation, support on site (excluding travel costs) Training on site (excluding travel costs) • Geophysical survey support Related products EBP Silas RheoTune Object detection Stema EBP Sub-bottom profi ler system is available for rent. Geo Consulting Survey vessel IntelliWinch HSP winch 15 ׉ 7cassandra://SfvVDSQ3vmLbJzMHhUdbTQB7iThlYm8WKnT4vDtBLxA`̵[s[s{בCט{u׉׉ 7cassandra://RaNyIEEamTG-XN62iqLteLD8lQ-tuT3L6J6Oxeg9aNc` ׉ 7cassandra://8ONae78AVs04xjL7o7vfCwySlJydy2UAKMTkhIxj7uUQ`S׉ 7cassandra://1sQ74B9RWoExXhzrIQXVn_F_h-xCj96CHMY9Y52XIcEQ`̵׉ 7cassandra://BGEZsMLgJ0rJ1V1DT-VaA4pqY3bw4RVFA5zo2bwn8ZcnU͠[s3ט{u׉׉ 7cassandra://fBGdrgFSgzNx2Zn_qOCzHTvtQkN4L32Q31WDdjoKSlM ` ׉ 7cassandra://yR_6HDXb3yWOU-aCVTrTJZIy7b2tFe82mRtAGmqIK-Y+`S׉ 7cassandra://KlY-cp96-3tuNBUKTpcKt_ep0Rb2mm1Gd5RSSvbMP9I2`̵׉ 7cassandra://AYVjQjYchN_UMyIhEZF0PQgfP-E3fVlxl7f-PuAGq1oT͠[s4נ[s6yc 9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉ETIntelliWinch Automated hydrographic and rheological equipment deployment Deliverables • Transfers data real-time • Maintains hover altitude automatically • Fully automated The IntelliWinch is a compact size instrumentation winch steered with a PC based control unit that can be integrated with other sensors for fully automated operation. Thus facilitating both horizontal as well as vertical deployment of hydrographical equipment. The IntelliWinch system is designed to enable the highest productivity when acquiring water column data, fluid mud proffiiles amongst others. Working with equipment such as the RheoTune , Side Scan Sonar, SVP, etc. probe short turn-around times for nautical depth surveys. e I h system is designed to enable the highest productivity when acquiring water column data, fl uid amongst others. Working with equipment such as the RheoTune probe short turn-around times for nautical depth surveys. The design focuses on fully automated measuring cycle with suffi cient guarantees for probe safety. Speed over ground and echo-sounder nadir depth input are combined with operator set thresholds to account for external factors when using in combination with Side Scan Sonars and other towed equipment. IntelliWinch installed on a moving frame. Smart software enables user to gain insight in height above seabed of towed equipment. Key features • Programmable deployment • Multiple equipment application • Vertical and horizontal towed deployment functionality IntelliWinch used to enable RheoTune measurements. Related products RheoTune Sales & rental HSP winch www.stema-systems.nl ׉ 7cassandra://1sQ74B9RWoExXhzrIQXVn_F_h-xCj96CHMY9Y52XIcEQ`̵[s׉EIntelliWinch Automated hydrographic and rheological equipment deployment Specifications Load capacity: Drum capacity: Max speed: Drive type: Power: Dimensions: Weight: Material: Winch control: 80 kg 100 m (dependent on cable choice) 90 m/min 2 m/sec 230 V single-phase electric power 2 kW 0.8 x 0.8 x 0.6 (L x W x H) 120 kg SS Stainless steel LAN Data communication: LAN / COAX / RS485 / RS232 Accessories: Slipring Handheld End-stop sensor Slackwire sensor Automated winch control Echosounder depth input IntelliWinch engine endstop & slackwire system Applications • Sound Velocity Sensors • Rheotune • Side Scan Sonar systems • Sub-bottom Profi lers 17 ׉ 7cassandra://KlY-cp96-3tuNBUKTpcKt_ep0Rb2mm1Gd5RSSvbMP9I2`̵[s[s{בCט{u׉׉ 7cassandra://N6rj9AcSrr4yC2-jVw6HJOR7FTo3DYEgqTDk6w3Mz4Yv` ׉ 7cassandra://qJcU7kTlxT58l2vTXPke-SU_YhPXHD3INcv2vJ3e-CIP`S׉ 7cassandra://HkvuTkugBF4OJSzLQbTkgVojdA1oKuGX7I5V73rfMLM+`̵׉ 7cassandra://OQiw5GplyNu2QioXBkxx5csNEnffTyi2pFbY22vXKS4l͠[s7ט{u׉׉ 7cassandra://i3vz2bL01KCm7KPsJeDFFpyrcW6CO3en4uHZSrnXv2ERI` ׉ 7cassandra://wf8CaAnqURO57P1pCkv-U5o60ywdnBUo0P8uVRafPPI4`S׉ 7cassandra://HNOfbbPUUjktZkgXb5i1-3vD7QvdLtHx1baeT6DBpSg`̵׉ 7cassandra://IORhYeHq0XnevESvv_ESgkAjaUx-5z7Q9VeWqF8jT3c͠[s9נ[s;yc 9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉EHSP winch High Speed Power winch for offshore purposes Deliverables • Rapid deployment of measurement systems up to 2000 m • Employment of multiple sensors simultaneously • Real-time data transfer • Maintains altitude automatically • Real-time interface with on-board PC’s The High Speed Power winch has been developed for the fast deployment and retrieval of various sensors in deep waters. The functionality of the winch benefi ts from the integration of the dedicated Stema Systems software that allows the winch to maintain altitude above the sea/lake fl oor of the sensors that it is towing. The altitude maintenance functionality has been proven to provide an added safety margin in the deployment of sensors such as a Side Scan Sonar as well as providing consistency of results in the deployment of magnetometers, both needing a consistent altitude for optimal functioning. The High Speed Power winch is designed such that it can rapidly deploy multiple sensors simultaneously up to a depth of 2000 meters. The winch can be operated with Rheotune software or with Stema dedicated winch software enabling fully automated measurement cycles, which can be displayed on the interface screen on deck. Among the parameters that can be set are: the maximum speed over ground (SOG), speed to lower the sensor, measurement speed. The lowering of the probe can be stopped automatically using various stopping criteria set in the winch software or by manual operation. The latter is enabled by a handheld near the winch and a additonal handheld located on the bridge of the ship. Internals of High Speed Power winch Compact High Speed Power winch with extendable arm to control fl eet angle Key features • Enabled for vertical deployment and towed devices • Multiple equipment deployments • Programmable deployment, for both vertical deployment and constant altitude maintenance Related products RheoTune IntelliWinch www.stema-systems.nl ׉ 7cassandra://HkvuTkugBF4OJSzLQbTkgVojdA1oKuGX7I5V73rfMLM+`̵[s׉EBHSP winch High Speed Power winch for offshore purposes Specifications Load capacity: Drum capacity: Max speed: Drive type: Power: Dimensions: Weight: Material: Winch control: 420 kg 2000 m (dependent on cable choice) 2 m/s 380 V three-phase electric power 10.7 kW 1.24 x 0.78 x 1.17 (L x W x H) 380 kg SS Stainless steel LAN Data communication: LAN / COAX / RS485 / RS232 Accessories: Slipring Cable counter Diameter Sensor Flashing light Measurement and regulation of cable tension Two handhelds End-stop sensor Slackwire sensor Extendable arm to control fl eet angle Applications • Sound Velocity Sensors • Rheotune • Side Scan Sonar systems • Sub-Bottom Profi lers • Combined Side Scan Sonar and Sub-Bottom Profi ling systems • Magnetometer (arrays) Offshore vessel for HSP winch HSP winch with lexan security cover 19 ׉ 7cassandra://HNOfbbPUUjktZkgXb5i1-3vD7QvdLtHx1baeT6DBpSg`̵[s[s{בCט{u׉׉ 7cassandra://BNRIejTQ72mKF2Trx6-LB9qXM5b2Sau8oESjd2ZViMwM@` ׉ 7cassandra://jnNUlwvxGPvxubgNspJtvsGABpwpJGmVQevpv07T7gYL`S׉ 7cassandra://MWTh62rnipqjo83f8ZRUB737JEUY6Q7-8SQJ91I245o`̵׉ 7cassandra://wX8_U-Himj6JGMU4YZPZkbTUtwhsmkKX6wkq-6h83NIx@͠[s<ט{u׉׉ 7cassandra://tizWlPRqp7HO84AbS7zlwZn4OCHgklak5mqn4lXG3B8y` ׉ 7cassandra://0LGgry1txQhwZg6SfGY1m6qVN0T4qI6yuaHayrUhXDY-`S׉ 7cassandra://ZACQKkGFXNymjUvI1zdxtV5CsU1cMhVC1cLUhVdZDmUv`̵׉ 7cassandra://ssF3irOuYVjO7isSKqoiquaxobJPhP-2Jqbgvo0ZTuYO͠[s=נ[s?yc 9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉ESurvey vessel Plug and play survey ready Deliverables • Full customizable Survey vessel • World wide reach in a container • Real-time data transfer from vessel to shore Stema Systems’ 30 years of surveying experience within the hydrography and geophysical fi eld has led to the design of this practical, highly manoeuverable lightweight, trailerable and containerised boat. Reason for us to build our boat was to get the highest quality data while surveying and to minimize the mob and demob costs. This boat is a turn-key survey vessel, calibrated and ready to survey. Crews reach and survey larger areas in less time, the pre-calibrated survey gear allows them to quickly start working. It works fast and comfortable for its crew. It saves lots of time and money for her owners. Highly manoeuvrable plug & play Survey vessel in action during trials. Hoisting eyes are present to deploy the vessel from almost any dock. Key features • Survey ready • Calibrated and ready to go • Pick and mix survey equipment Related products EBP Silas The light-weight vessel fi ts into a standard container so it can easily be deployed all over the world. RheoTune Object detection Geo Consulting Sales & rental IntelliWinch www.stema-systems.nl ׉ 7cassandra://MWTh62rnipqjo83f8ZRUB737JEUY6Q7-8SQJ91I245o`̵[s׉ESurvey vessel Plug and play survey ready Specifications Characteristics LOA 7.25 m BOA Draft 2.28 m 0.70 m Dry Weight 2,220 kg incl. engines Engine Honda LKU Type Propulsion Speed Range Fuel Crew limit Hull & Cabin Material Shape Climate Windows Transport 2 outboard 60hp Sterndrive 40 km/h +/- 275 km 190 L 4 Survey Equipment Multibeam Singlebeam Geotechnical Motion sensor 5 mm sea grade aluminum V- bottom Air-conditioned cabin Double glazing Trailerable Containerable Hoisting eyes Sound Velocity Positioning Software Interior Plug & play Survey vessel • Bench & desk for surveyors • Comfortable captain chair • Waterproof interior woodwork • Storage compartments • Necessary sailing equipment • Chart plotter, radar, autopilot, etc. 40 ft HC Container Workspace contains: • Total station and internet connection • Sleep and shower facility R2Sonic Stema EBP RheoTune IX Blue AML Stema GNSS Qinsy 21 ׉ 7cassandra://ZACQKkGFXNymjUvI1zdxtV5CsU1cMhVC1cLUhVdZDmUv`̵[s[s{בCט{u׉׉ 7cassandra://hrdhTOe21uAM8RA_oL5oL8qrj2FHmrSRnWnJjWbvXOg` ׉ 7cassandra://mdBEHeLw1NJfNAvCW1EPmexwrMcr6QfSgoodBQmOL54I6`S׉ 7cassandra://oMzJ9KYx43u8yrnLJ_ZvSMKitIabDIJtZLvBcsLz67E`̵׉ 7cassandra://jjGZHUfq3M9WZa0FeekxXk-3s_aM6A6d5-wYAz4IC7k͠[s@ט{u׉׉ 7cassandra://X6Ew349brMEbwFcA2xWXMAjtj4uU4oe9yTBMnoeIns4)` ׉ 7cassandra://_2l_kqF1RR6-ZqMHwVrZzvXVkCcOIefvPuIieoAknKIA`S׉ 7cassandra://cD4GnaBnJF63egWajLEKPAcOxtgBzispNxlwiEw3qHQ`̵׉ 7cassandra://qYXQbmuuO_Ja0wS-W2sfg5GQVbUvYTLjt0Er1GX4zQAj͠[sAנ[sCyc 9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉EGeo consulting Geological and seismic analysis and project advise Deliverables • Pre-survey advise • Processing • Interpretation and reporting Stema Geophysical Consulting has proven its added value many times. Due to our hydrographical and geophysical experience the consultants know the best way to prepare and /or process your sub-bottom survey. Our approach guides you to an effi cient and effective survey for the best results. • Inventarisation i.e. desired result, methodology and equipment choice • Initiation of survey i.e. mobilization, fi ne tuning and training • Processing raw data • Interpretation of data into established deliverables Data processing can commence as soon as data has been acquired. Stema’s consultants offer their assistance to their clients in the early stages of a (geo-seismic) project. Thereby establishing the appropriate project approach and the application of the relevant equipment, processing resulting in more effi cient and accurate processing. As a result the clients survey team is provided with the right tools to acquire the raw data in order to obtain the best quality result for further processing, which takes place in our offi ce where the raw data will be processed by our highly experienced geophysicists. Key features • • • Vast geophysical equipment knowledge Large pool of professionals processors On-site analysis pre-report ysical equipment knowledge l of professionals processors (geologists) si e analysis pre-report Experienced Stema personel can assist in sparker and boomer surveys, both single- and multi-channel. Related products EBP Silas RheoTune Object detection Geo Consulting Sales & rental Survey vessel IntelliWinch Silas record acquired with a boomer. www.stema-systems.nl ׉ 7cassandra://oMzJ9KYx43u8yrnLJ_ZvSMKitIabDIJtZLvBcsLz67E`̵[s׉EGeo consulting Geological and seismic analysis and project advise Our team Stema Systems has developed a market leading sub-bottom profi ling methodology using a combination of uniquely designed equipment with in-house developed software, resulting in a system that can provide a host of sub-bottom analysis results catering to the clients’ specifi c needs. Over the past 30 years this combination of hardware and software has resulted in thorough insights into the sub-bottom in which we now consult. The way our team works is easy and reliable. Each project will be executed by a junior or medior geophysical consultant depending on the skills needed for the project and is always monitored by one of the senior geologists. For each assignment a plan will be made in collaboration with the customer and internally approved by the senior geologists. The fi nal client report will be signed off by the project consultant and the senior geologist. Each staffmember has at least 5 years of experience and holds a MSc Geology degree. Every employee at Stema also has knowledge of hydrological equipment and hydrographical fi eld experience. Our references 23 ׉ 7cassandra://cD4GnaBnJF63egWajLEKPAcOxtgBzispNxlwiEw3qHQ`̵[s [s{בCט{u׉׉ 7cassandra://yCZlPZYoTWSXm6XXRtGIYsTKg7gY11XmVVGhvmEDnDI` ׉ 7cassandra://Xf_3q6r61ShOZh7Q00l8HcWDa8N3IHpeJPT8ojfUp5AL `S׉ 7cassandra://xpDnt_tsoBxLtfbC0TgwgWH87ixCSjxOmFcdQG5tXfY`̵׉ 7cassandra://yYXOy5Q9ncLb_ntoDkrdQYTeg0E0WXUPCedwZoxcyxk;{͠[sDט{u׉׉ 7cassandra://mBiLoh6g0f71KEbCLDd_JE1gjkVALAe8YNgGEXTlIC0` ׉ 7cassandra://mR7sT9axCTnNZL5czGW0UmOM11ZEjliEMAe8CYLi9okO&`S׉ 7cassandra://amziKForr2sGXf3ac_5oHzgtMUCQxhzdI6TXF76D_2c`̵׉ 7cassandra://2Zg6aZMWx2A9ucOHATNSav-dB8CTqg-8KOB9Ew2i3SE{ ͠[sHנ[sJyc 9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉E Sub-bottom pipeline and cable detection using automated contact recognition Author: J. KWEE ABSTRACT As more and more wind energy parks are build offshore these days, the need for detecting and mapping the existing infrastructure below the water bottom becomes increasingly vital. Relatively small and easy to deploy sub-bottom profi ling systems provide high resolution 2-D single channel seismics. In this high resolution seismic data, pipelines and cables are identifi ed by the display of hyperbolas. The top of the hyperbola indicates the top of the cable, which is used to determine the exact position and depth of burial. These contacts can be determined manually, taking into account human error and inconsistency. A new development within the geophysical software package Silas is the automated contact recognition technique for the detection of these hyperbolas. The contact recognition consists of the automated determination of two parameters: 1) the semblance of the apex of the hyperbola and 2) the accumulated power of the hyperbola. These parameters are quantifi able fi gures which enables a more objective classifi cation of detected contacts. Other datasets, as multibeam, sidescan sonar and magnetometer data, can be combined with the sub-bottom data within the software for cross correlation and clear imaging of the sea bed and below. INTRODUCTION With the presence of more and more pipelines and cables in the coastal waters, the need to determine the exact location increases. This extended abstract will focus on sub-bottom detections of cables and pipelines using single channel shallow seismic data and describes the automated contact detection of Silas. Vital information with regards to cables is the depth of burial of cables and pipelines. A changing bathymetry can create free span of cables, which could lead to potential dangers of an interrupted power or communication grid. If the location and depth is known, risks can be mitigated before mayor problems arise. Methods using an active signal on pipeline or the cable may detect this properly, but result in a shutdown of the cable for the time of monitoring. A passive method to detect these cables and pipelines is sub bottom profi ling and will be discussed in this extended abstract. Sub-bottom profi ling - Single channel 2-D seismic data Most of the sub-bottom marine infrastructure is situated in the top part of the seabed. Sub-bottom profi ling uses transducers both sending and receiving the signal resulting in 2-D, single channel seismic profi les. These small systems can easily be mounted, also on smaller vessels, allowing easy surveys in coastal and even inland waters. The lower the frequency of a signal, the deeper the penetration, but at the cost of a lower resolution. This tradeoff should always be kept in mind, when picking a frequency for object detection. Important questions are: at what (burial) depth do we expect the cable and what is the size of the object that should be detected. Especially for the detection of cables, a high resolution is needed in the top part of you sub-surface. The beam width and footprint of a sub bottom profi ler are bigger than each of the individual beams of www.stema-systems.nl ׉ 7cassandra://xpDnt_tsoBxLtfbC0TgwgWH87ixCSjxOmFcdQG5tXfY`̵[s ׉Esurvey methods that only image the seafl oor itself, as a multibeam. This inherently decreases the resolution of detection. Using multiple transducers in an array increases the signal/noise ratio in the overlapping ellipse. Nevertheless, the bigger beam width can be used as an advantage for the detection of cables and pipelines. These features are visible in sub bottom data as hyperbolas. As can be seen in Figure 1, part of the signal refl ects on top of an object before the vessel sails right above it, due to this larger beam width. It is, however, plotted as if it is detected right below the vessel, but at greater depth. The closer the vessel sails to the pipeline or cable, the shallower it shows up in the sub-bottom data. The shallowest point is reached right on top of the cable. A reverse trend occurs moving away from the linear object, resulting in a hyperbola. Acquisition and processing The acquisition of sub bottom data for the detection of cables and pipelines involves the sailing of crosslines on top of the linear object. The more pings refl ect on top of the linear object, the more clear the hyperbola can occur in the data, so a slow survey speed and a high pingrate are recommended. As described in the fi rst section, the recorded data is a sub-bottom acoustic profi le. As always the case with sub-bottom data, the raw signal is processed, but interpretation to identify the seafl oor, geological layers and objects has to be made. Results are less straight forward hydrographical methods like multibeam surveys, that give direct results of the depth of the seafl oor. Other than multichannel data, single channel sub-bottom profi les can be viewed directly as recorded without any processing needed. However, no fi lters or heave reduction are (fully) applied to the online data. This makes it less clear if objects are detected directly. For data quality purposes data should be processed quickly and verifi ed. An easy option to apply a quick review of the data is to use an automated batch processing as is available in the Silas Processing software suite. Figure 1: Object detection in acoustic data. Above the different path lengths to the object are displayed depending on the location. Below the corresponding acoustic traces, resulting in a hyperbole, highlighted in red. Another advantage that sub-bottom profi ling (and seismic data in general) have above other detection methods is that, besides the detection of the objects themselves, the complete subsurface is imaged. This allows also to detect bottom features related to the constructions of pipes and cables as trenches, initially dredged to lay them in. The extra information helps interpretation and could give an indication, even if the pipelines and cables are not detected themselves. Interpretation of the seafl oor is relatively easy and is mostly done by auto-tracing algorithms. For layers in the subsurface, interpretation need to be a bit more manual, especially if layers are not as distinct. The interpretation of objects can even be more complicated. Several diffi culties that can occur during this interpretation, as is also stated by (Wunderlich et al., 2005) , are: • Objects can be masked by refl ections of nearby layers (as the seafl oor or other layer boundaries) and other structures. • Weak echo strength due to acoustic attenuation in the sediment. • Small refl ection coeffi cients due to small acoustic difference (density, sound velocity) to surrounding material. • Small dimensions of objects and unknown or imprecise know positions. The picking of cables, pipelines and objects in sub-bottom data is mainly interpretation work that requires experience of the personnel and these man made interpretations change between different individuals. 25 ׉ 7cassandra://amziKForr2sGXf3ac_5oHzgtMUCQxhzdI6TXF76D_2c`̵[s [s {בCט{u׉׉ 7cassandra://1pSfqzONL0VVTNfGQTxXvZD113LxULUUSj7oJFH6nls4$` ׉ 7cassandra://sqnWKFxDCBg7BJa3DAHKXZSdiZetu1Nq0zw5PjRzWxkP`S׉ 7cassandra://C3j_BSf67S1w9WuOnJD4_FTNq72XmyqTDsE6D3FKZxg`̵׉ 7cassandra://_xZ6SMLtGCmk2SAXj-p17ahiZ3GKxRDAZaqOW3aN60Q͠[sKט{u׉׉ 7cassandra://6ApAwvHES66RVBy71Wn2XyFo_crY1QGytoqdRn4fp24` ׉ 7cassandra://rfqPZ2Yc_nh6ERh_Q2ZVhnM4539v5jG0XITXLC-hh1UF%`S׉ 7cassandra://DF9IxI3fNA8Vgz8dVDK3_tThaEG3UMZMKU3sLAKxU3I`̵׉ 7cassandra://gab9538uV0v9P1mXWIFnelP14OvTifyT26pmIvPUMwY ͠[sLנ[sPL̤9ׁHhttp://www.stema-systems.nlׁ ׁ Јנ[sO=9ׁH#mailto:jasper.kwee@stema-systems.nlׁ ׁ Ј׉EAutomated contact detection To lower the infl uence of subjective interpretation, Silas Processing has a module which applies an automated contact detection algorithm to the data. As stated earlier, linear objects appear as hyperbolas in perpendicular sailed sub-bottom profi les. The automated contact detection calculates theoretical hyperbolas for a given window and set velocity range. This procedure can be run for a great number of lines, resulting in automated picked contacts on each line, saving time compared to manual picking. Contacts can be inspected on the seismic profi les and also in a vertical depth display, showing the depth of the contacts for one pipeline or cable. This algorithm is constant in the way contacts are detected, while human interpretation can vary over time and per individual. Figure 2 shows the different steps in for the automated contact detection. In this example, two pipelines close to one another, were present, showing clear hyperbolas. A) shows the raw data, without any fi ltering, as recorded during acquisition. B) shows the data after batch processing sequence. C) indicates the results of the automated object detection, indicating the contacts with triangles. The bottom of Figure 2 (D) shows a vertical section, perpendicular to all the sailed profi les (but parallel to the pipeline). All auto-detected contacts of one pipeline are shown with a triangle and a contact number. Small triangles above show the location of the seafl oor in each line. In grey, a third-order polynomial estimation of the pipeline location is shown. Values for two parameters are calculated during the automated contact detection algorithm: accumulated power and semblance (fi t to a theoretical hyperbola) giving a quantifi cation of the detected contact. These parameters are also calculated for the complete selected window and are shown on the location of the cursor. These horizontal intervals are shown above the seafl oor in purple and red in Figure 2). The parameters allow a more quantifi able interpretation of objects when manual picking is used. The theoretical hyperbola calculated hyperbola can also be plotted on top of the shallow seismic profi les. This can be used to visually check the correspondence to the sub-bottom data, but enables also object detection if the top of the hyperbola is not visible due to overprinting. Figure 2: Examples of the automated contact detection procedure from Silas Processing. A): Raw sub-bottom data, B) batched processed sub-bottom data, C) processed data with automated contact detection applied, D) vertical depth display with all detected contacts (DE BOER, 2016). Combination of data The more data is available, the better and easier the interpretation in sub-bottom data will be. As-laid information from cables and pipelines can be imported to decrease or defi ne the horizontal window of search for the automated contact detection. Bottom-surface data as multibeam and sidescan sonar, can detect frees pan of cables and pipelines and confi rm detections on the bottom. The cross correlation that can be made between the data sets gives an extra quality control. The Silas software is able to import and combine both these different data formats. Figure 3 shows an example of the combination of multibeam data from the seabed in combination with sub-bottom acoustics. A clear pipeline can be seen surfacing at the multibeam data. The location of the cross lines is plotted on top. In the lower cross line (in red) the pipeline is covered with sediments. However, the seismic profi le (left part of Figure 3) shows the location of this pipeline below the sediments. Contacts can be picked (automated) in the seismic data, but also on the multibeam data. Also already identifi ed contacts, for instance in magnetometer data, can be loaded. All data and contacts, picked or loaded from other data formats, are combined within the same software, resulting in a comprehensive overview for a linear object. www.stema-systems.nl ׉ 7cassandra://C3j_BSf67S1w9WuOnJD4_FTNq72XmyqTDsE6D3FKZxg`̵[s ׉E(Figure 3: In the right image, multibeam data is plotted with a surfacing pipeline. Crosslines can be seen on top of the multibeam data indicating the location of the sub-bottom profi les. The sub-bottom seismic data of the red (lower) crossline is shown on the left with clear hyperbole. Conclusion Sub-bottom profi ling can be successfully used to detect linear objects within the bottom. The automated contact recognition of Silas detects objects in an automated way. The calculated quality parameters allow for a quantifi able interpretation and the comparison with the theoretical hyperbola increases the ease of manual interpretation. The combination with other datasets increases the quality of interpretation in sub-bottom acoustics. Related products EBP Silas Biographical notes References DE BOER, P.J., WERNER, C.J. (2016): Provide end users with the most accurate nautical depth measurement by using the combination of echo sounders and density measurement equipment, HYDRO 2016. WERNER, C.J. (2016): A fl exible high resolution seismic method for qualifi cation of the seabed, Hydro International 16, January. WUNDERLICH, J, WENDT, G and MULLER, S (2005): High-resolution echo-sounding and detection of embedded archaeological objects with nonlinear sub-bottom profi lers, Marine Geophysical Researches (2005) 26:123-133. J. Kwee graduated in 2012 with a MSc in geophysics from the University of Utrecht. In the same year he joined Stema Systems as a geologist. He is involved in the training, implementation and development of Stema’s geophysical products including but not limited to seismic software Silas and high-resolution sub-bottom profi lers. CONTACT J. Kwee Stema Systems Poppenbouwing 52 Geldermalsen The Netherlands Tel. +31 345 580 395 Email: jasper.kwee@stema-systems.nl Website: www.stema-systems.nl 27 ׉ 7cassandra://DF9IxI3fNA8Vgz8dVDK3_tThaEG3UMZMKU3sLAKxU3I`̵[s [s {בCט{u׉׉ 7cassandra://Pd5pH87z1CEhwZ7heD0XPh-tOswbUB3SM9rFzofx9nA͋v` ׉ 7cassandra://Ni2Spqi657GbAo8vsp0VsqLmGDPoVhHVPaDiVZRQB1U`S׉ 7cassandra://iultFdeNiIs0FUS8tnJca1cZbsVK5IzgrzCfUEuFnisf`̵׉ 7cassandra://U1dKDtM_y3_pk8pyE2_7cxkhodcjAkm5j4JOA5Tk1dg$s ͠[sQנ[sŞɁ̧9ׁHhttp://www.stema-systems.nlׁ ׁ Ј׉EfStema Systems Poppenbouwing 52 Geldermalsen The Netherlands Tel. +31 345 580 395 www.stema-systems.nl ׉ 7cassandra://iultFdeNiIs0FUS8tnJca1cZbsVK5IzgrzCfUEuFnisf`̵[s׈E[s[s{)Stema Brochure 2018eSub bottom software Silas, sub bottom profilers, Densitune and Rheotune Consulting and survey support[Sd^