Composition and Sources of Clay from the Trench Slope and Shallow Accretionary Prism of Nankai Trough

Slope, Trench; Trough, Nankai; Underwood, Michael B.; Steurer, J.

doi:10.2973/odp.proc.sr.190196.206.2003

Cited by 23 publications

(20 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The CEC values, as well as their range of variation is smaller for the Nantroseize transect than at the sites previously drilled on the Muroto and Ashizuri transects [Underwood and Steurer, 2003;Henry and Bourlange, 2004] (Figure 1). However, substantial variations in the CEC content are observed across lithological boundaries (Figure 3), especially at Site C0001 between the slope apron and the accreted sediments (Figures 3 and 4).…”

Section: Cec and Lithologymentioning

confidence: 90%

“…drilling Leg 131,190 and 196 located in the Muroto transect ( Figure 1) and from IODP expeditions 315 and 316 located in the Kumano transect ( Figure 1) indicated that an important proportion of the clay minerals present within the Nankai sediments is smectites [Henry and Bourlange, 2004;Underwood and Steurer, 2003;Kinoshita et al, 2009], and that smectite interlayered water can be present at levels up to 25% of the total volume of water [Henry and Bourlange, 2004]. [9] In water-saturated sediments 'total porosity' is defined in laboratory measurements as the ratio between the total volume of water removed by oven drying at 105°C and the wet sample volume.…”

Section: Geological Background Drilled Sitementioning

confidence: 99%

“…Method 3.1. Interstitial Porosity Determination on Core Samples [10] Porosity measurements performed on the cores using standard methods [Blum, 1997] reflect the total water content present within the sediments including the water contained in hydrous minerals, which primarily refers to smectites in the case of the Nankai sediments [Henry and Bourlange, 2004;Underwood and Steurer, 2003]. Previous researches proposed correction for bound water based on smectite content determinations obtained using XRD [Brown and Ransom, 1996;Hashimoto et al, 2010].…”

Section: Geological Background Drilled Sitementioning

confidence: 99%

“…However, porosity measurements depend upon the lithology and the clay mineralogy, especially upon the water bound to hydrous minerals [e.g., Brown and Ransom, 1996]. In the case of Nankai, smectite is the dominant mineral that holds bound water interlayered between its silico-aluminate sheets [Henry and Bourlange, 2004;Underwood and Steurer, 2003]. This water should be considered as an intrinsic part of the mineral, as most of it is retained during compaction under the P and T conditions that prevail at this setting [Brown and Ransom, 1996;Colten-Bradley, 1987].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Interpretation of porosity and LWD resistivity from the Nankai accretionary wedge in light of clay physicochemical properties: Evidence for erosion and local overpressuring

Conin

Henry

Bourlange

et al. 2011

Geochem Geophys Geosyst

View full text Add to dashboard Cite

[1] In this study, we used porosity to assess the compaction state of the Nankai accretionary wedge sediments and any implications for stress and pore pressure. However, hydrous minerals affect porosity measurements, and accounting for them is essential toward defining the interstitial porosity truly representative of the compaction state. The water content of sediments was measured in core samples and estimated from logging data using a resistivity model for shale. We used the cation exchange capacity to correct the porosity data for the amount of water bound to clay minerals and to correct the porosity estimates for the surface conductivity of hydrous minerals. The results indicate that several apparent porosity anomalies are significantly reduced by this correction, implying that they are in part artifacts from hydrous minerals. The correction also improves the fit of porosity estimated from logging-while-drilling (LWD) resistivity data to porosity measured on cores. Low overall porosities at the toe of the accretionary wedge and in the splay fault area are best explained by erosion, and we estimated the quantity of sediments eroded within the splay fault area by comparing porosity-effective stress relationships of the sediments to a reference curve. Additionally, a comparison of LWD data with core data (resistivity and P wave velocity) obtained at Site C0001 landward of the mega-splay fault area, suggested a contribution from the fracture porosity to in situ properties on the formation.

show abstract

Section: Cec and Lithologymentioning

confidence: 90%

Section: Geological Background Drilled Sitementioning

confidence: 99%

Section: Geological Background Drilled Sitementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Interpretation of porosity and LWD resistivity from the Nankai accretionary wedge in light of clay physicochemical properties: Evidence for erosion and local overpressuring

Conin

Henry

Bourlange

et al. 2011

Geochem Geophys Geosyst

View full text Add to dashboard Cite

show abstract

“…Pliocene and Pleistocene sediments are enriched in detrital illite and chlorite, whereas Miocene deposits contain more smectite. This is likely due to a change in sediments provenance (Izu Bonin volcanic arc in Miocene versus Japan metamorphic mountain belts in Pliocene-Pleistocene) (Underwood and Steurer 2003).…”

Section: Mineralogical/lithological Variationsmentioning

confidence: 99%

Rock magnetic characterization of ferrimagnetic iron sulfides in gas hydrate-bearing marine sediments at Site C0008, Nankai Trough, Pacific Ocean, off-coast Japan

Kars

Kodama

2015

Earth Planet Sp

View full text Add to dashboard Cite

A high-resolution rock magnetic study was carried out in Integrated Ocean Drilling Program (IODP) Expedition 316 Hole C0008A located in the Megasplay Fault Zone of the Nankai Trough, SW offshore Japan, in order to document changes in magnetic properties throughout gas hydrate-bearing horizons. A total of 169 Pleistocene discrete samples were collected from~110 to 153 m core depth below sea floor (CSF), and their magnetic minerals concentration, grain size, composition, and rock magnetic parameters were estimated. Results showed the presence of iron oxides ((titano)-magnetite), iron sulfides (greigite and pyrrhotite), and their mixture, among which single-domain greigite is the most major magnetic mineral present in the samples. Two horizons containing ferrimagnetic iron sulfides (114.5-127.5 and 129.5-150 m CSF) covering almost the entire studied interval were identified, both associated with slight local pore water anomalies, suggesting occurrence of gas hydrates and anoxic conditions. These results are different from the neighboring Hole C0008C (215 m away from Hole C0008A) where four pore water anomalies and six iron sulfide-rich intervals were identified for the same time slice. Comparison of the lithology, physical properties, and geochemical data of the two boreholes at Site C0008 suggests that a combination of processes (e.g., availability of reactive iron, microbial activity) is responsible for such laterally varying distribution of the ferrimagnetic iron sulfides.

show abstract

Evolution of Sedimentary Environments in the Subduction Zone v of Southwest Japan: Recent Results from the NanTroSEIZE Kumano Transect

Underwood

Moore

2011

Tectonics of Sedimentary Basins

View full text Add to dashboard Cite

The Nankai Trough is located off the coast of southwest Japan, where the Philippine Sea plate is subducting beneath the Eurasian plate. The margin's Kii Peninsula or Kumano Basin corridor is the focal area for the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE). This multi-disciplinary, multi-stage, multi-expedition project was designed to improve our understanding of seismogenic processes along the plate interface. Drilling Stage 1 of NanTroSEIZE included Expeditions 314, 315, and 316 of the Integrated Ocean Drilling Program. Coring and logging during those three expeditions generated a wealth of new information about the stratigraphic and structural evolution of the margin. Our summary descriptions are organized into three broad domains: the Kumano (forearc) Basin; the megasplay fault zone, which is a significant out-of-sequence thrust within the accretionary prism; and the frontal thrust zone of the accretionary prism. For the most part, drilling results validate structural interpretations of 3D seismic-reflection data, but they also place invaluable constraints on the timing of such events as the initiation of forearc-basin sedimentation and the history of slip on the megasplay fault. We see many types of interaction between tectonics and sedimentation. The frontal thrust zone is dominated by packets of sand and gravel that probably accumulated within trench-floor axial channel systems prior to their accretion in the early Pleistocene. The accretionary prism becomes progressively older toward land, and a time-transgressive unconformity separates the prism from the overlying slope apron. Turbidite sedimentation within the Kumano Basin did not begin until the early Pleistocene, after a succession of precursor events: formation of the underlying accretionary prism during the late Miocene and early Pliocene; erosion of an unconformity above the accretionary prism, with an associated hiatus of $1.2 My; a long phase of unusually slow hemipelagic sedimentation, lasting from $3.8 Myr to $1.67 Myr; acceleration of uplift along the megasplay fault at $1.55 Myr, which enhanced accommodation space; and organization of a robust sediment-delivery system, which was achieved through uplift and erosion of the hinterland and incision of canyons and gullies into the upper trench slope.

show abstract

Composition and Sources of Clay from the Trench Slope and Shallow Accretionary Prism of Nankai Trough

Cited by 23 publications

References 70 publications

Interpretation of porosity and LWD resistivity from the Nankai accretionary wedge in light of clay physicochemical properties: Evidence for erosion and local overpressuring

Interpretation of porosity and LWD resistivity from the Nankai accretionary wedge in light of clay physicochemical properties: Evidence for erosion and local overpressuring

Rock magnetic characterization of ferrimagnetic iron sulfides in gas hydrate-bearing marine sediments at Site C0008, Nankai Trough, Pacific Ocean, off-coast Japan

Evolution of Sedimentary Environments in the Subduction Zone v of Southwest Japan: Recent Results from the NanTroSEIZE Kumano Transect

Contact Info

Product

Resources

About