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In July 2019, approximately 217 km of 2-D multichannel seismic reflection data were collected along 27 profiles on Oneida Lake, New York using a 120 channel Seamux™ solid-towed array marine streamer with a 3.125 m group interval and a maximum offset of ~400 meters. Data were recorded in SEG-D format on a NTRS2 recording system. The seismic source was a 4x10 in3 Bolt 2800 LLX airgun array and was towed at ~1 meter depth to allow for venting of seismic source air bubbles. Gun pressures varied from 1500 to 2000 PSI. Air guns were fired every 6.25 m distance using two high resolution (Trimble) GPS receivers for navigation. This geometry provided 30-fold seismic coverage with a common midpoint (CMP) interval of 1.56 m. Record length is 2 seconds and the sample rate is 0.25 ms. These raw field shot data files are in SEG-D format, bundled by seismic line. The files were acquired as part of a project called P2C2: A High Resolution Paleoclimate Archive of Termination I in Oneida Lake and Glacial Lake Iroquois Sediments. Funding was provided through NSF grant EAR18-04460 to Syracuse University.
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Raw high-resolution multi-channel seismic reflection (MCS) field data from the JS2203 Gulf of Mexico Campeche Bank Seismic Survey (2022)
This data set consists of raw multi-channel seismic reflection (MCS) data in SEG-Y format, collected in July 2022 along the continental slope of the Campeche Bank aboard R/V Justo Sierra. The research objective was to map the detailed stratigraphy of sediment drift deposits to explore the history of the Loop Current and its climatic implications. We used the portable high-resolution seismic acquisition system operated by Scripps Institution of Oceanography, which comprised a source array of two 45 cubic inches G.I. air-guns and a GeoEel streamer with 120 channels at a spacing of 6.25 m. The air-gun array was fired every 12.5 m and was towed at a depth of 3 m. Data was recorded using the Geometrics seismic recording system with sample rate of 0.5 ms and recording length of 4 ms. A 50-ms delay was created during each shot as a buffer between the timing pulse that starts the recording and the trigger pulse that fires the air-guns. A total of 11 seismic lines were acquired including two long strike lines, five dip lines, two tilted dip lines and two short transition lines. The shot spacing was not exactly 12.5 m during the first three lines (1001-1003) due to system glitches, therefore, it is necessary to merge navigation with SEG-Y headers to ensure accurate processing of these lines. Detailed acquisition parameters and cruise incidents are described in the associated documents. Funding for this work was provided through NSF awards OCE-1928888 and OCE-1450528, and CONTEX award 2018-38A.
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- Award ID(s):
- 1928888
- PAR ID:
- 10498674
- Publisher / Repository:
- Interdisciplinary Earth Data Alliance (IEDA)
- Date Published:
- Subject(s) / Keyword(s):
- Seismic Reflection MCS SEG-Y
- Format(s):
- Medium: X
- Location:
- IEDA Academic Seismic Portal
- Sponsoring Org:
- National Science Foundation
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In July 2019, approximately 217 km of 2-D multichannel seismic reflection data were collected along 27 profiles on Oneida Lake, New York using a 120 channel Seamux™ solid-towed array marine streamer with a 3.125 m group interval and a maximum offset of ~400 meters. Data were originally recorded in SEG-D format on a NTRS2 recording system. Navigational data and ancillary data (ship speed, depth, etc.) were fed into the external header of each field file. The seismic source was a 4x10 in3 Bolt 2800 LLX airgun array and was towed at ~1 meter depth to allow for venting of seismic source air bubbles. Gun pressures varied from 1500 to 2000 PSI. Air guns were fired every 6.25 m distance using two high resolution (Trimble) GPS receivers for navigation. This geometry provided 30-fold seismic coverage with a common midpoint (CMP) interval of 1.56 m. Record length is 2 seconds and the sample rate is 0.25 ms. The following processing steps were applied to the dataset using SeisSpace/ProMAX Software. Data were initially reviewed in shot mode and noisy traces were edited. Geometry was applied using source and receiver offsets with group and shot intervals, and data were sorted into the CMP domain. Stacking velocities were picked using a combination of velocity semblance plots and constant velocity stacks applied to CMP supergathers. For the constant velocity stacks, supergathers were constructed from 51 CMPs and analyzed in increments of 100 CMPs. Once time-velocity pairs were selected, normal moveout was applied to the full profile data set and the data were stacked.Nested Ormsby bandpass filters of 110-135-1500-1700 Hz and 40-70-1100-1300 Hz were applied to the stacked datasets. Ormsby filter frequencies were picked by executing a careful parameter test where frequencies were altered incrementally until the ideal filter was produced. A post-stack F-K filter was applied to remove steeply dipping noise, and a careful comparison of F-K filtered profiles and raw profiles was conducted. A post-stack Kirchhoff time migration with a 200 ms bottom taper was applied using the RMS stacking velocities picked for each seismic profile. The data files are in SEG-Y format and were generated as part of a project called P2C2: A High Resolution Paleoclimate Archive of Termination I in Oneida Lake and Glacial Lake Iroquois Sediments. Funding was provided through NSF grant EAR18-04460 to Syracuse University.more » « less
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