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The pre‐Cenozoic structural pattern of Asia has had a strong impact on the localization and propagation of the Cenozoic deformation that gave birth to the Tibetan Plateau. Northern Tibet represents a key area to decipher the structural and kinematic links between the Mesozoic and Cenozoic evolution of Tibet. Nonetheless, the Mesozoic tectonic setting of the North Tibet and the role that the Paleozoic inherited Altyn Tagh Fault (ATF) shearing zone played in controlling the regional tectonic pattern during the deposition of the Mesozoic strata remain controversial. This study is based on seismic reflections, isopach maps of the Mesozoic strata in the Qaidam Basin, and provenance analysis using detrital zircon geochronological and heavy mineral contents. Seismic reflections and isopach maps demonstrate that sustained strike‐slip motion along the ATF during the Early to Late Jurassic induced transtensional basin formation. Further away from the main ATF (eastern parts of the Qilian Shan and the northern Qaidam Basin), transtension also occurred along major faults, although local transpression developed in relay zones. Rotation in the regional stress field induced compression and basin inversion during the Late Jurassic to Early Cretaceous. The Cenozoic sedimentary rocks in these regions display widespread growth strata and angular unconformities characteristic of compression. This is consistent with topographic changes marked by sediment source variation evidenced by detrital zircon geochronology and heavy mineral analysis. We propose that the mechanism driving the Jurassic extension/transtension in North Tibet could be related to far‐field effects of subduction processes along the southern margins of the continent. Key Points: Mesozoic strike‐slip motion along the Altyn Tagh Fault (ATF) shearing zone controlled the formation of transtensional basinsChange in the direction of regional stress field occurred during the Late Jurassic‐Early CretaceousThe Qilian Shan and the Qaidam Basin were completely inverted under a N‐S or NE‐SW oriented compression during the Early Cenozoic [ABSTRACT FROM AUTHOR]

The Paleogene Lulehe Formation marks the onset of deposition in the Qaidam basin and preserves evidence of the initial topographic growth of northern Tibet. However, limited outcrops impede understanding of the sedimentary features of the Lulehe Formation as well as the tectonic relationship between the basin and surrounding topography. To fill this gap, we investigated core samples along the basin margin and conducted flexural modeling to estimate the topographic load of the Qilian Shan and Eastern Kunlun Shan during the deposition of the Lulehe Formation. Core samples reveal that the Lulehe Formation mainly consists of distal fluvial to marginal lacustrine deposits and proximal fluvial deposits along the southern margin of the basin while characterized by proximal alluvial fan deposits along the northern margin of the basin. Together with evidence for faulting shown on the seismic profiles, we infer that simultaneous deformation within the Qilian Shan and Altyn Tagh Shan during the Paleogene resulted in accumulation of coarse detrital deposits in the northwestern and northeastern Qaidam basin. The simultaneous deformation within the Altyn Tagh Shan and Qilian Shan since the Paleogene supports the idea that deformation in these two regions is kinematically linked. One‐ and two‐load beam flexural modeling indicates that the topographic load generated by both the Eastern Kunlun Shan and the Qilian Shan is responsible for the subsidence of the Qaidam basin during deposition of the Lulehe Formation. Our results highlight the initial relative high topography in the northern Tibetan plateau during the early Cenozoic. Key Points: We carry out flexural modeling to estimate the initial topographic load of the Qilian Shan and Eastern Kunlun ShanLulehe Formation consists of distal fluvial‐marginal lacustrine and proximal fluvial‐alluvial fan deposits along the margins of the basinBoth Qilian Shan and Eastern Kunlun Shan topographic loads account for the initial subsidence of the Qaidam basin [ABSTRACT FROM AUTHOR]

Two debated age models, with a basal age of ~50 Ma versus ~30 Ma, are proposed for the depositional age of Cenozoic strata within the Qaidam basin result in a diverse understanding of the initial pattern of deformation in the northern Tibetan Plateau. To evaluate these age models, we integrated isopach maps within the basin with published thermochronology data from surrounding ranges to balance the sediments preserved in the basin with materials eroded in the drainage area. When following the traditional ~50 Ma age model, the total volume of material eroded from the surrounding source area is 4.4 ± 0.3 × 105 km3. Using instead the ~30 Ma age model for the basal Lulehe Formation and related revisions to the basin chronology, the volume of eroded material is calculated at 3.5 ± 0.2 × 105 km3, which provides a better match to the calculated total volume of solid grains that are preserved in the basin (2.8 ± 0.1 × 105 km3). However, growth strata revealed in seismic profiles along the Southern Qaidam Thrust suggest reverse‐faulting began during the deposition of Oligocene‐Miocene strata. Following the ~50 Ma age model, the onset time of faulting along the Southern Qaidam Thrust is ~35.5 Ma, consistent with previous thermochronology results. If both age models are correct, then this requires a significant time‐transgressive nature to basin fill that allows for older ages of deposition in the southern part of the basin. This study highlights the need for further effort to determine the depositional age of the strata in the southern and western parts of the Qaidam basin. Key Points: We balance the sediment volume preserved in the Qaidam basin with material eroded in the surrounding rangesWe tested two competing models of basin fill and erosion commencing 30 and 50 MaOur analysis is consistent with both the 30 and 50 Ma ages suggesting time‐transgressive basin fill [ABSTRACT FROM AUTHOR]

The recent rise of institutional timberland ownership has led to a significant change in the structure and conduct of the timber industry in the United States. In this study, we apply a two-period harvest model to assess the timber harvesting behavior of various landowners at the stand level by utilizing USDA Forest Service Forest Inventory and Analysis data for nine southern states. Forest industry and institutional timberland owners were found to be more likely to conduct partial and final harvests than nonindustrial private forest landowners. Aggregately, Timberland Investment Management Organizations were found to be most, and timberland Real Estate Investment Trusts to be least, price-responsive among ownership groups. [ABSTRACT FROM AUTHOR]

Over the past 30 years the U.S.-Canadian softwood lumber trade dispute has resulted in three managed trade agreements that have not been voted on in the U.S. Congress. Nevertheless, U.S. Senators have played an important role in shaping the political environment that has nurtured these agreements. In this paper we construct a lumber influence index based on 14 known events between 2001 and 2006 and analyze what factors influenced a senator's decision to publically call for restricting Canadian lumber imports and to adopt the 2006 Softwood Lumber Agreement. Our results show that the size of the wood products manufacturing industry in a state, campaign contributions, logrolling, and ideology played a significant role and that interest group politics is prevalent in this dispute. Au cours des 30 dernières années, le différend commercial entre le Canada et les États-Unis au sujet du bois d'œuvre résineux s'est soldé par trois accords de commerce administré qui n'ont pas été mis au vote du Congrès des États-Unis. Néanmoins, les sénateurs américains ont joué un rôle important dans le façonnement du climat politique dans lequel ces accords ont été préparés. Dans le présent article, nous avons mis au point un indice de l'influence fondé sur 14 événements connus qui se sont déroulés entre 2001 et 2006, et nous avons analysé les facteurs qui ont influencé un sénateur à préconiser publiquement des restrictions sur les importations de bois d'œuvre canadien et à adopter l'Accord sur le bois d'œuvre résineux en 2006. Les résultats de notre étude montrent que la taille de l'industrie de la fabrication des produits en bois dans un État, les contributions aux campagnes, les alliances politiques dans un but intéressé et l'idéologie ont joué un rôle considérable et que l'influence des groupes d'intérêt a été un facteur apparent dans ce différend. [ABSTRACT FROM AUTHOR]

This article presents a theoretical framework and empirical evidence on the relationship between regulatory uncertainty induced by the possible invasion of' an endangered species -- the red-cockaded woodpecker (RCW) -- and timber harvesting. The results indicate that landowners whose forests are close to a known or perceived RCW habitat have a high propensity to cut timber and use a clear-cut method. These preemptive actions are apparently aimed at destroying potential RCW habitat so that the existing values of their property could be protected from the Endangered Species Act (ESA) -- related land use limitations. [ABSTRACT FROM AUTHOR]

Public choice economics view legislative process as a transaction in the political market. Interest groups demand regulation in their favor and lobby lawmakers. The lawmakers analyze an assortment of factors and supply legislation to the winning group, thereby maximizing their rent from the political market. This article examines Endangered Species Act (ESA) amendments from a public choice perspective. Congressional voting on the ESA amendments are assessed using a model based on political incentive and ideology. The results show that the lawmakers' voting behavior is correlated with their party affiliation, ideology, and several characteristics of their home state, such as number of endangered species, proportion of urban population, contribution of the natural resources and construction sectors in gross state product, and geographical location. [ABSTRACT FROM AUTHOR]

Capital asset pricing model (CAPM) and arbitrage pricing theory (APT) are used to assess the financial performance of eight forestry-related investment vehicles. Although results from APT support previous findings from CAPM about timberland investments, three bodies of evidence show that APT findings are more robust. The major conclusions are (a) institutional timberland investments and timberland limited partnerships have a low risk level and excess returns; (b) forestry industry companies have not earned risk-adjusted returns, and the performance of medium forest industry firms is worse than that of large firms; (c) stumpage price does not resemble the return generation process of timberland investments; and (d) lumber futures have little excess return. [ABSTRACT FROM AUTHOR]