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The dip and anisotropy of an anisotropic formation were algebraically determined from the transient triaxial induction data without inversion. The time-dependent apparent dip and the apparent anisotropy, algebraically defined from the triaxial transient induction measurements, were applied in a two-layer formation. The apparent dip yielded the true dip in an anisotropic formation, as well as in layered formations, though it yielded the zero dip in an isotropic formation. At early time the apparent anisotropy yielded the true anisotropy of the layer on which the induction tool was located, and at later time the macroscopic anisotropy for a larger volume of investigation. The distance to the layer interface was identified by the transition time when the apparent dip and the apparent anisotropy change the values.

The triaxial (or multicomponent) induction log is used to measure not only the resistivity anisotropy of an anisotropic formation but also the relative dip of the tool with respect to the formation. The anisotropic resistivity and the relative dip of layered formations are also inverted from the triaxial induction-log measurements at a depth by assuming a homogeneous anisotropic formation or at multiple depths by assuming a multilayered formation model. When the triaxial induction log is run at multiple frequencies, multifrequency focusing can be applied to the log measurements. Then, the apparent dip is algebraically defined from the frequency-focused triaxial induction measurements at a depth. The apparent dip yields the true dip in an anisotropic formation. The algebraically calculated apparent dip may be used to determine the effective dip in layered formations. The apparent dip yields the true dip in thinly bedded formations. The apparentdip also yields the true dip in thick anisotropic formations. However, the apparent dip yields a smaller dip than the true dip when the anisotropy is small (the anisotropy effect). It yields a much smaller dip in thick isotropic formations. Like the apparent dip, the apparent anisotropy is algebraically defined from the frequency-focused triaxial induction measurements at a depth. The apparent anisotropy yields the true anisotropy in an anisotropic formation. The algebraically calculated apparent anisotropy may be applied to layered formations. The apparent anisotropic resistivity (horizontal and vertical) can likewise be determined algebraically from the frequency-focused triaxial data. In contrast to the apparent dip, which yields the true dip in thinly bedded formations but not in thicker formations, the apparent anisotropy yields the true anisotropy in thick anisotropic formations but not in thinner anisotropic formations. The apparent anisotropy is affected by the shoulder-bed anisotropy when the formation is not thick (the shoulder-bed effect).

The tri-axial (or multi-component) induction log is used to measure not only the resistivity anisotropy of an anisotropic formation but also the relative dip of the tool with respect to the formation. When the tri-axial induction log is run at multiple frequencies, multi-frequency focusing can be applied to the measurements. The apparent dip and the apparent anisotropy are algebraically deflned from the frequency-focused tri-axial induction measurements. The apparent dip gives the true dip in thinly bedded formations, but a smaller dip than the true dip in a thick anisotropic bed when the anisotropy is small (the anisotropy efiect). The apparent anisotropy gives the true anisotropy in thick anisotropic formations but is afiected by the shoulder bed anisotropy when the formation is not thick (the shoulder bed efiect).

Summary We examined the response of directional resistivity tools with tilted antennas to a VTI anisotropic formation. A new method is proposed to determine the VTI anisotropic resistivity (with the horizontal resistivity and the vertical resistivity) and the formation dip using the directional resistivity tool with single transmitter-receiver offset at one

We examined the tool response of coaxial tool in a layered isotropic earth model, and provide methods to determine the distance to bed and the resistivity of the bed beyond the boundary from a set of tool responses. We also examined the tool response of a directional resistivity tool with tilted transmitter/receiver antenna(s) in a layered isotropic earth model. The difference between the downward receiver response and upward receiver response can be used as interface indicators. We provide methods using the interface indicators to simultaneously determine the distance to bed and the resistivity of the bed beyond the boundary. We examined the effect of layer anisotropy in the distance to the boundary (D2B) and resistivity determination by modeling responses of a coaxial tool and a directional resistivity tool in layered anisotropic earth models. When the tool is in an anisotropic layer such as shale, the anisotropy of the layer significantly affects the tool response and the D2B estimate has to be corrected for the anisotropy. When the tool is in an isotropic layer, the anisotropy of an adjacent layer will affect the tool response less. However, the anisotropy effect gets larger when the adjacent anisotropic layer is less resistive. The effect of anisotropy has to be corrected only at the short distance from the boundary. Based on the modeling results, we propose a method to account for the anisotropy effect and correctly estimate the D2B and resistivity beyond the boundary.

Summary Formation compaction in unconsolidated geopressured turbidite reservoirs in the Gulf of Mexico (GOM) is an issue of great uncertainty and concern. When compaction occurs, it changes the porosity and permeability properties of the reservoir rock and can affect recovery efficiency and well productivity. It can deform well tubulars, creating operational problems and shortening well life. If compaction is significant, especially when multiple stacked reservoirs are involved (as in the case in this field example), then compaction can create a subsidence bowl at the ocean floor. In GOM offshore operations, this could cause platforms to subside deeper into the water and create potentially severe safety problems; therefore, failure to properly address issues of compaction and subsequent subsidence during the design and development phases of these capital intensive, deepwater projects could lead to severe financial setbacks. It is crucial to have a compaction monitoring program in place because of the broad impact of compaction and seafloor subsidence. As a result, we developed a new formation-compaction monitoring tool (FCMT) and new methods of measurement and interpretation. The FCMT is a wireline device that uses multiple gamma ray detectors to determine locations of and precise distance between radioactive (RA) markers planted in the formation or casing. Compaction of the formation can be measured by changes in the distance between the markers. For precise estimation of the vertical distance between a pair of markers, the new method uses an array of three or four detectors. By examining the tool response to a marker, we developed a new method to determine the exact vertical and lateral location of the marker by using a Lorentzian response model; consequently, not only the vertical compaction but also lateral displacement of markers can be monitored with the new method. The accuracy of the tool was established in the test facility where gamma ray sources were placed at precisely known intervals. The tools were run centralized at three logging speeds (5, 10, and 15 ft/min.), and data were collected at 0.1-in. intervals. The vertical distances between a pair of RA markers spaced 30 ft apart were measured accurately to within 0.1 in. The first baseline logs were collected successfully in the four wells in a GOM deepwater development. High consistency among measurements from different logging passes proved that the FCMT can provide precise distance measurements with newly developed methods.

Summary We examine induction log responses to layered, dipping, and anisotropic formations analytically. The analytical model is especially helpful in understanding induction log responses to thinly laminated binary formations, such as sand/shale sequences that exhibit macro-scopically anisotropic resistivity. We discuss two applications of the analytical model. In one application, we examine special induction log shoulder-bed corrections for use when thin anisotropic beds are encountered. It is known that thinly laminated sand/shale sequences act as macroscopically anisotropic formations. Hydrocarbon-bearing formations also act as macroscopically anisotropic formations when they consist of alternating layers of different grainsize distributions. When such formations are thick, induction logs accurately read the macroscopic conductivity, from which the hydrocarbon saturation in the formations can be computed. When the laminated formations are not thick, proper shoulderbed corrections (or thinbed corrections) should be applied to obtain the true macroscopic formation conductivity and to estimate the hydrocarbon saturation more accurately. We use the analytical model to calculate the thinbed effect and to evaluate the shoulder-bed corrections. We show that the formation resistivity and, hence, the hydrocarbon saturation are greatly overestimated when the anisotropy effect is not accounted for and conventional shoulder-bed corrections are applied to the log responses from such laminated formations. In another application, we examine the effect of shale anisotropy in thinly laminated sand/shale sequences. How do induction logs respond to such laminated formations when shale laminae are anisotropic? How accurate are the estimates of the sand-laminae resistivity and of the hydrocarbon saturation in these sand laminae? To answer these questions, we used the analytical model to examine the effect of shale lamina anisotropy on induction log responses in thinly laminated formations. We learned that the macroscopic conductivity of a laminated formation is determined uniquely by the sandlaminae conductivity and the anisotropic shale conductivity, if the sand fraction is known. We also found that the sand resistivity estimate depends on the value of shale resistivity and the dip angle, if the shale is assumed to be isotropic and if the sand fraction is known. When the sand fraction is not known, the sand resistivity and the sand fraction can be estimated if the set of horizontal and vertical macroscopic resistivities is known. In this case, the sand resistivity tends to be overestimated if the shale anisotropy is not accounted for. On the other hand, the sand fraction estimate is generally insensitive to the shale anisotropy, except for low sand-laminae resistivity (Rsd/Rsh < 5).

Summary The CSEM data are grouped into the data sets with constant transmitter-receiver offsets. Symmetrized data set with a constant offset may be used to identify a resistivity anomaly with the depth of investigation approximately of the transmitter-receiver offset. Symmetrized data sets from different offsets with multiple depths of investigation may help to determine the location and the resistivity of a resistivity anomaly. An anti-symmetrized data set (differential amplitude) with the constant offset may be used to easily detect the lateral boundary of the resistivity anomaly. The method is also applicable to the streamer EM data where the data are collected with constant offsets to begin with.

Summary Anisotropic resistivity is not uncommon in electromagnetic logging environments. Many shale formations are known to be anisotropic. Thinly laminated sand/shale sequences behave as macroscopically anisotropic formations. We analyzed the tool response to anisotropic resistivity for each type of EM logging tool: electric resistivity logs, induction type logs, and toroidal resistivity tools. In particular, the effect of anisotropy on the logging-while-drilling 2-MHz induction-type resistivity log is discussed in detail. The effect causes differences between phase-derived and attenuation-derived apparent resistivities, between apparent resistivities from different transmitter-receiver spacings, and between apparent resistivities measured at different operating frequencies. Based on the tool response analysis, we present a method to estimate anisotropy from log data. An application to laminated sand analysis is discussed, in which the sand lamina resistivity and the net-gross ratio (N/G) are determined simultaneously.

Summary We examine induction log responses to a thinly laminated sand/shale sequence in a deviated borehole for arbitrary deviation (or dip) angle and sand/shale composition. We found that the induction log responses in a thinly laminated sand/shale sequence are the same as they would be if the tool is placed in a homogeneous but anisotropic formation with the horizontal and vertical conductivities given respectively by the parallel and the series conductivities of the sequence. Conversely, a thinly laminated sand/shale sequence can be identified as an anisotropic formation by induction logs. We discuss three methods to identify an anisotropic formation using induction-type logs alone.

Fourteen types of corona discharge needles made of different materials were used for high performance liquid chromatography/atmospheric pressure chemical ionizationquadrupole mass spectrometer (LC/APCI-QMS), and after a lapse of one hour and five hours from the start of the equipment, selected-ion monitoring determination of 3,5-di-tert-butyl-4-hydroxytoluene (BHT) was made seven times repeatedly. Suitability as a discharge needle was judged by the total (n=14) relative standard deviation (T-RSD) of the quantitative determination value. T-RSD's of the iron needle, tin-plated iron needle, silver alloy needle, platinum alloy needle and stainless steel needle were 1-3%.It could be elucidated from the scanning electron micrograph of the needle surface that suitability as a discharge needle was related to the stability of needle surface material against the corona discharge. The iron needle, having a small T-RSD was judged to be the most suitable as a corona discharge needle for quantitative analysis.

Summary Several recently published studies discuss the concept of inductive resistivity-logging devices with oblique transmitting and/or receiving coils. Both wireline induction and logging-while-drilling (LWD) propagation resistivity-tool concepts have been considered. Directional resistivity measurements and improved anisotropy measurements are among the benefits promised by this type of device. Analyses based on point-magnetic dipole antennas were used to illustrate these potential benefits. The effects of a metallic mandrel, borehole, and invasion were not considered because of the absence of a suitable forward model. This paper characterizes mandrel, borehole, and invasion effects for a variety of candidate tilt-coil devices with antenna array parameters similar to those of the previous studies. The characterization is based on calculations from a new forward model that includes tilted transmitting and receiving coils of finite diameter embedded in a concentric cylindrical structure. Important details of the forward model used in the calculations are also provided.

A simple method using Florisil cartridges was developed for the determination of dimethylformamide (DMF) in sucrose esters of fatty acids present in sugar esters (SuE) and sucrose acetate isobutyrate (SAIB) used as food additives. SuE was dissolved in acetone and loaded on a Florisil cartridge. SAIB was dissolved in hexane, loaded on a Florisil cartridge and washed with 10% acetone in hexane. The columns were eluted with acetone and DMF in the eluates was determined by GC with an FID detector. Recoveries of DMF at the level of 0.5-100 micrograms/g were 93.3-102.6%. The determination limit was 0.5 microgram/g.

A selected-ion monitoring (SIM) determination of serum lycopene, alpha-carotene and beta-carotene by an atmospheric pressure chemical ionization mass spectrometry (APCI-MS) was developed. A large amount of serum cholesterols disturbed the SIM determination of carotenoids by contaminating the segment of interface with the LC-MS. Therefore, separation of carotenoids from the cholesterols was performed using a mixed solution of methanol and acetonitrile (70:30) as the mobile phase on a C18 column of mightsil ODS-5 (75 mm x 4.6 mm I.D.). The SIM determination was carried out by introducing only the peak portions of carotenoids and I.S. (squalene) by means of an auto switching valve. In the positive mode of APCI-MS, lycopene, alpha-carotene and beta-carotene were monitored at m/z 537 and I.S. was monitored at m/z 411. This method was linear for all analytes in the range of 15-150 ng for lycopene, 7-70 ng for alpha-carotene and 25-50 ng for beta-carotene. The detection limit of LC-APCI-MS-SIM for carotenoids was about 3 ng per 1 ml of serum (S/N = 3). The repeatabilities, expressed as C.V.s, were 10%, 8.4% and 5.3% for lycopene, alpha-carotene and beta-carotene, respectively. The intermediate precisions, expressed as C.V.s, were 11.2%, 8.8% and 6.5% for lycopene, alpha-carotene and beta-carotene, respectively.

Abstract Thinly laminated sand/shale sequences are often mistaken as low-resistivity wet sands in spite of their high hydrocarbon saturations, because conventional electric logs and induction logs read the low average resistivity of the formations. Imaging tools and other high-resolution logging tools may be needed to identify such laminated formations when cores are not available. Such formations appear as homogeneous and anisotropic formations to conventional resistivity tools when the typical lamina thickness is much finer than the tool's vertical resolution. The anisotropic formation resistivity is determined by the sand- and shale-laminae resistivities, and the sand fraction (or sand/shale ratio). Conversely, the sand-laminae resistivity can be estimated from the anisotropic resistivity data if the shale-laminae resistivity, the sand/shale ratio, and the relative dip (deviation) angle are all known. We call this approach to laminated-sand analysis the "macroscopic anisotropy" approach. When multiple resistivity values are measured, as in the case of using LWD 2-MHz resistivity devices in highly deviated boreholes, the sand-laminae resistivity and the sand/shale ratio can be estimated simultaneously from the anisotropic resistivity measurements. We examine the sensitivity of sand-laminae resistivity determination to each parameter and review how these parameters are estimated. The two most sensitive parameters are the shale-laminae resistivity and the sand/shale ratio, especially at smaller dip angles. When the total thickness of such a laminated sequence is not thick and/or sand laminae are invaded with mud formation evaluation becomes complicated, because the logging tools cannot read the macroscopic resistivity correctly. To estimate the correct macroscopic resistivity, special shoulder-bed (or thin-bed) corrections and/or invasion corrections must be applied. We examine special shoulder-bed corrections for anisotropic formations at higher dip angles. In homogeneous anisotropic formations, significant borehole effect is observed for laterologs and spherically focused logs (SFLs), but not for induction logs. We found that difference between induction-log resistivity and laterolog- or DFL/SFL-log resistivity is logarithmically proportional to the formation anisotropy, but is almost independent of borehole size. The difference may be used to estimate the formation anisotropy. Shale formations are often anisotropic. The effect of shale anisotropy is examined and a method is provided to correct such shale anisotropy in laminated-sand analysis. Introduction: Macroscopic Anisotropy Approach to Thin Bed Problems Consider a thinly laminated sand/shale (or any binary) sequence. Even fine-resolution resistivity tools, such as DFL/SFL and high-frequency dielectric tools (HFDTs, EPTs) fail to differentiate sand and shale laminae. Neither induction tools nor laterolog tools can even detect lamination when the lamination is much thinner than the tools' vertical resolution. Instead, these tools respond to a thinly laminated sand/shale sequence as though it were a homogeneous low-resistivity formation even though the sand lamina may be very resistive. Any logging tool has its own thin-bed problem when bed thickness is comparable to or thinner than its vertical resolution. When beds are thinly laminated and any resolution improvement is not available, an alternative "macroscopic anisotropy" approach becomes useful. We ignore the detail of individual laminae in this approach. and throughout a sequence we assume that all sand laminae are identical and all shale laminae are identical. P. 275^

Abstract Formation compaction in unconsolidated geo pressured turbidite reservoirs in the Gulf of Mexico (GOM) is an issue of great uncertainty and concern. When compaction occurs, it changes the porosity and permeability properties of the reservoir rock and can affect recovery efficiency and well productivity. It can deform well tubulars, creating operational problems and shortening well life. If compaction is significant, especially when multiple stacked reservoirs are involved (as in the case in this field example), then compaction can create a subsidence bowl at the ocean floor. In GOM offshore operations, this could cause platforms to subside deeper into the water and therefore create potentially severe safety problems. Therefore, failure to properly address issues of compaction and subsequent subsidence during the design and development phases of these capital intensive, deepwater projects could lead to severe financial setbacks. Because of the broad impact of compaction and seafloor subsidence, it is crucial to have a compaction monitoring program in place. As a result, we developed a new Formation Compaction Monitoring Tool (FCMT) and new methods of measurement and interpretation. The FCMT is a wireline device that uses multiple gamma-ray detectors to determine locations of and precise distance between radioactive markers planted in the formation or casing. Compaction of the formation can be measured by changes in the distance between the markers. For precise estimation of the vertical distance between a pair of markers, the new method uses an array of three or four detectors. By examining the tool response to a marker, we developed a new method to determine the exact vertical and lateral location of the marker using a Lorentzian response model. Consequently, not only the vertical compaction but also lateral displacement of markers can be monitored with the new method.. The accuracy of the tool was established in the test facility where gamma-ray sources were placed at precisely known intervals. The tools were logged centralized at three logging speeds (5, 10, and 15 ft/min.), and data were collected at 0.1 in. intervals. The vertical distances between a pair of radioactive markers spaced 30 ft apart were measured accurately to within 0.1 in. The first base-line logs were collected successfully in the four wells in a GOM deepwater development. High consistency among measurements from different logging passes proved that the FCMT can provide precise distance measurements with newly developed methods. Introduction Formation compaction is a major concern in unconsolidated sand reservoirs. Compaction can reduce formation porosity and permeability, affecting long-term hydrocarbon production from the reservoir. Compaction can deform well tubulars, creating operational problems and shortening well life. If compaction is significant, it can cause subsidence of ocean floor, leading to severe safety problems for offshore platforms.

Perchloric acid-soluble fractions (PASFs 1-3) which were obtained from cyst fluids of two patients [(Nos. 1 (blood group B) and 2 (blood group A))] with ovarian mucinous cystadenoma and one patient (No. 3 (blood group A)) with ovarian dermoid cyst in benign, were identified as glycoproteins by their chemical composition analyses, respectively. Reactivities of PASFs 1-3 against blood group anti-sera and lectins suggest that these PASFs did not contain MN blood group substances, Vgu glycoproteins and T-active glycoproteins. PASF 1 was separated into 11 fractions by Sephacryl S-500 gel filtration. From chemical composition, SDS-PAGE and serological property of the main fraction (Fr. 5), other one fraction (Fr. 7) and mild acid hydrolysates of these two fractions, it is possible to presume that PASF 1 consisted of a large number of AB-active and fucose-rich glycoproteins with high molecular weights and some of these glycoproteins bear either NeuNAc alpha 2-->6GalNAc (sialyl Tn) group or both sialyl Tn and sialylated T groups.

The quantities of the sweetener aspartame (APM) and its decomposed product, diketopiperazine (DKP), in chocolate, soy sauce and miso paste were determined by high performance liquid chromatography/atmospheric pressure chemical ionization mass spectrometry with selected-ion monitoring. APM and DKP were extracted from the foodstuffs with water and a solid-phase extraction was carried out. The extracted APM and DKP were separated on an analytical C-4 reversed-phase column with ammonium formate buffer (0.05mol/L, pH 4.0) containing 20% methanol as the mobile phase and o-hydroxybenzamide as the internal standard (IS). In the negative mode, APM, DKP and IS were monitored at m/z 293, m/z 261 and m/z 136, respectively. The limit of determination for APM and DKP in the sample was 5μg/g and the recoveries of APM and DKP were 53-83% and 69-101%, respectively. This method enabled the determination, for the first time, of DKP in chocolate, soy sauce and miso paste.

Lycopene, α-carotene and β-carotene in canned vegetable juice were determined by high performance liquid chromatography/atmospheric pressure chemical ionization mass spectrometry (LC/APCI-MS) with selected ion monitoring (SIM). The extracted carotenoids were separated on a C-18 reversed phase column with methanol as the mobile phase and cholesterol benzoate as an internal standard (IS). In order to obtain good repeatability, only the peak portion of analytes eluted from the LC column was introduced into the APCI interface by using an auto switching valve. In the positive mode, lycopene, α-carotene and β-carotene were monitored at m/z 537 and IS was monitored at m/z 369. The limit of detection was 1ng (s/n=4) and the recoveries of lycopene, α-carotene and β-carotene were 85.1%, 80.0% and 82.8%, respectively.This SIM determination using LC/APCI-MS allows the analyte in samples to be determined without the influence of co-existing substances which cause problems in LC-UV chromatography.

ジゴキシン錠中のジゴキシゲニン(D0),ジゴキシゲニソモノジギトキソサイド(D1)及びジゴキシゲニンピスジギトキソサイド(D2)のHPLCによる定量法を開発した.又,錠剤の溶出試験液をクロロホルム抽出し,この溶出液中のジゴキシン加水分解物の組成比を求めた.錠剤6銘柄から,D0,D1及びD2それぞれ,0.13～1.84,0.16～0.29及び1.60～4.19μg/錠を検出した.組成比はD0が最も多く,42.5～46.4%であった.Dlは約17%,D2は約20%であり,ジゴキシンの組成比は15.7～20.2%であった.

錠剤に微量混在するギトキシンの高速液体クロマトグラフィー(HPLC)による分離定量法を確立した。70%メタノール液2.5mlを加え,10分間超音波照射を行った場合,0.7mgまでギトキシン量とピーク面積に直線性を認めた.ギトキシン5μg,250μg及び700μgを添加したところ,平均回収率は96%以上,又,相対標準偏差はそれぞれ,2.69%,1.11%及び1.58%であり,精度のよい信頼性のある定量法であると考えられた.ジゴキシン錠から最高0.34%のギトキシンを検出したが,ジギトキシソ錠及びラナトシドC錠からギトキシンを検出しなかった.これまで強心配糖体の錠剤に混在すると報告されながら,必ずしも明らかでなかったギトキシン含量が,本法により把握することが可能になった.

A vacuum gauge field Aμa for Yang-Mills theory is constructed; this field (i) is pure vacuum (Aμa=0) at the origin, (ii) approaches at large distances, the Belavin-Polyakov-Schwartz-Tyupkin pseudoparticle, and (iii) satisfies ∂μAμa=0 everywhere. The net topological charge is zero, and there is a Dirac-like string terminating at the origin.